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1
Marchi, D., D. Lanati, G. Mazza, and P. Cascio. "Composizione in antociani e flavonoli di vini prodotti nel territorio svizzero." BIO Web of Conferences 15 (2019): 02012. http://dx.doi.org/10.1051/bioconf/20191502012.
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In questa nota sono presentati i risultati delle determinazioni del profilo degli antociani e dei flavonoli di vini prodotti con uve di alcune varietà a frutto colorato prodotte a Nord della Svizzera, nel cantone di Schaffhausen , nella regione di Klettgau. I vini sono stati ottenuti da uve delle varietà di Vitis vinifera Cabernet Dorsa, Gamaret, Dornfelder, Acolon e di un incrocio interspecifico Sylvaner × Müller Thurgau × Chambourcin (Regent). Il profilo degli antociani dei vini delle varietà di Vitis vinifera studiate è risultato a netta prevalenza di molecole trisostituite all'anello laterale (soprattutto malvidina-3-glucoside e suoi derivati acilati). Il vino Regent si è rivelato ricco di antociani 3,5-diglucosidi (soprattutto della malvidina) che hanno superato in proporzione i monoglucosidi. Di rilevante interesse è risultato il profilo dei flavonoli per la presenza nei vini, appena dopo la fine della fermentazione alcolica, di quercetina aglicone, di solito assente nell'uva. I vini Acolon e Regent sono risultati i più ricchi di quercetina aglicone. L'origine della quercetina aglicone nei vini esaminati in questo lavoro è stata attribuita all'idrolisi che le forme glicosilate di questo flavonolo hanno subito, probabilmente per via enzimatica, già durante la macerazione fermentativa.
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Marchi, D., D. Lanati, P. Cascio, and M. Giacomo. "Influenza della sfogliatura sulla sintesi della quercetina in Sangiovese. Ulteriori acquisizioni sui precipitati di quercetina nei vini." BIO Web of Conferences 15 (2019): 02010. http://dx.doi.org/10.1051/bioconf/20191502010.
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Allo scopo di approfondire i fattori che portano ad un accumulo elevato dei flavonoli e in particolare dei glicosidi della quercetina nell'uva abbiamo valutato in campo l'influenza della defogliazione precoce e all'invaiatura e di altre variabili viticole sulla sintesi di questi composti. Nello stesso tempo abbiamo studiato l'influenza della refrigerazione del vino e della formazione di complessi con altre sostanze presenti nel vino sulla solubilità della quercetina aglicone. I risultati ottenuti hanno confermato che: i) la defogliazione, in particolare quella precoce, inducono un incremento della sintesi dei flavonoli nell'uva, ii) la quercetina aglicone forma complessi, presumibilmente con gli antociani monomeri e con certe classi di pigmenti polimeri, con un incremento sensibile della sua solubilità, iii) la refrigerazione dei vini in cui la quercetina aglicone è presente sopra la sua soglia di solubilità porta alla sua precipitazione.
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Lewis, David, Marie Bradley, Stephen Bloor, Ewald Swinny, Simon Deroles, Chris Winefield, and Kevin Davies. "Altering expression of the flavonoid 3′-hydroxylase gene modified flavonol ratios and pollen germination in transgenic Mitchell petunia plants." Functional Plant Biology 33, no. 12 (2006): 1141. http://dx.doi.org/10.1071/fp06181.
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Antisense technology was successfully used to reduce flavonoid 3′-hydroxylase (F3′H) gene expression and enzyme activity and to promote the accumulation of monohydroxylated flavonols in petunia flower tissue. The hydroxylation pattern of specific flavonoid groups is a target for modification because of the possible associated changes in a range of factors including colour, stress tolerance and reproductive viability. Petunia (cv. Mitchell) plants were transformed to express in the antisense orientation the sequences encoding the F3′H (asF3′H). Transformants showed a range of responses, in terms of the level of endogenous F3′H gene expression and the relative proportion of the monohydroxylated flavonol (kaempferol) glycosides that accumulated. Kaempferol glycosides increased from 7% of the total flavonols in flower limb tissue of the wild type plants, to 45% in the flower limb tissue of line 114, the transgenic line that also showed the greatest decrease in F3′H expression in flower tissue. In leaf tissue, the trend was for a decrease in total flavonol concentration, with the relative proportion of kaempferol glycosides varying from ~40 to 80% of the total flavonols. The changes in leaf tissue were not consistent with the changes observed in flower tissue of the same lines. Endogenous F3′H activity in flower limb tissue was not completely shut down, although an 80% decrease in enzyme activity was recorded for line 114. The residual F3′H activity was still sufficient that quercetin glycosides remained as the major flavonol form. Alteration of F3′H activity appears to have affected overall flavonoid biosynthesis. A decrease in total flavonol concentration was observed in leaf tissue and two other flavonoid biosynthetic genes were down-regulated. No morphological changes were observed in the transgenic plants; however, up to a 60% decrease in pollen germination was observed in line 13. Thus, the relatively small change in flavonoid biosynthesis induced by the asF3′H transgene, correlated with several other effects beyond just the specific biosynthetic step regulated by this enzyme.
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Joshi, Kunjani. "Leaf Flavonoid Patterns in the Species of Stemonoporus (Dipterocarpaceae) and Their Taxonomic Significance." Journal of Natural History Museum 24 (October 9, 2009): 146–55. http://dx.doi.org/10.3126/jnhm.v24i1.2291.
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During the chemotaxonomic study of 16 species of Stemonoporus, three flavonoid aglycones (flavonol quercetin, flavonol kaempferol and flavone apigenin) and glycosides (quercetin 3- glucoside, quercetin 3-rutinoside and apigenin 5-glucoside) were isolated while flavonol myricetin, flavone luteolin and proanthcyanidin were not detected in any of the species surveyed. The isolated flavonoids can be used as chemotaxonomic markers. The species of Stemonoporus can be regarded as advanced in flavonoid pattern because of the absence of myricetin and loss of proanthocyanidins. The data of the flavonoid patterns and the outcome of cluster analysis are taxonomically useful to resolve the controversies over the systematic arrangement of the species and suggest the need for a revision of classification of the genus Stemonoporus. Key words: Dipterocarpaceae; Flavonols; Chemotaxonomy; Cluster analysis. Journal of Natural History MuseumVol. 24, 2009Page: 146-155
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Ivey, Kerry L., Joshua R. Lewis, Richard L. Prince, and Jonathan M. Hodgson. "Tea and non-tea flavonol intakes in relation to atherosclerotic vascular disease mortality in older women." British Journal of Nutrition 110, no. 9 (April 29, 2013): 1648–55. http://dx.doi.org/10.1017/s0007114513000780.
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Epidemiological studies have indicated that dietary flavonoids generally, and flavonols specifically, may contribute to cardiovascular health. Tea consumption, which is often the main dietary source of flavonoids and flavonols, is associated with a reduced risk of cardiovascular outcomes. The primary objective of the present study was to explore the association of the habitual intake of flavonols from tea and non-tea sources with the risk of atherosclerotic vascular disease mortality in a population of elderly women. A total of 1063 women, aged over 75 years, were randomly selected from ambulant Caucasian women living in Perth, Western Australia. Flavonoid consumption was assessed using the US Department of Agriculture Flavonoid, Flavone and Proanthocyanidin databases. Atherosclerotic vascular disease mortality was assessed over 5 years of follow-up through the Western Australian Data Linkage System. During the follow-up, sixty-four women died from atherosclerotic vascular disease. Women in the highest compared with the lowest tertile of flavonol intake had a lower risk of atherosclerotic vascular disease death (OR 0·27, 95 % CI 0·13, 0·59; P≤ 0·01 for trend in multivariate-adjusted models). Similar relationships were observed for flavonol intake derived from both tea (OR 0·38, 95 % CI 0·18, 0·79; P< 0·01) and non-tea (OR 0·41, 95 % CI 0·20, 0·85; P= 0·05) sources. Tea was the main contributor to flavonol intake (65 %), and the intakes of flavonols from tea and non-tea sources were not significantly correlated. In conclusion, increased consumption of flavonols was independently associated with a lower risk of atherosclerotic vascular disease mortality. Both tea and non-tea sources of flavonols were independently associated with this benefit.
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Lumbessy, Mirna, Jemmy Abidjulu, and Jessy J. E. Paendong. "Uji Total Flavonoid Pada Beberapa Tanaman Obat Tradisonal Di Desa Waitina Kecamatan Mangoli Timur Kabupaten Kepulauan Sula Provinsi Maluku Utara." Jurnal MIPA 2, no. 1 (January 31, 2013): 50. http://dx.doi.org/10.35799/jm.2.1.2013.766.
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Penelitian ini bertujuan untuk menguji total kandungan flavonoid pada beberapa tanaman obat tradisional. Penentuan kandungan total flavonoid dilakukan dengan menggunakan metode etanol – HCl, sedangkan analisis flavonoid menggunakan Metode spektrofotometeyr UV-VIS . Hasil yang diperoleh menunjukan kandungan total flavonoid pada tanaman ketepeng cina (Cassia alata L) sebesar 26.8633 mg/mL , iler (Coleus scutellariodes L Benth) sebesar 14.425 mg/mL , rumput teki (Cyperus rotundus L) sebesar 6.505 mg/mL, pegagan (Centella asiatica) sebesar 3.816 mg/mL, rumput mutiara (Oldenlandia corymbosa) sebesar 2.686 mg/mL dan waru (Hibiscus tiliaceus L) sebesar 1.425 mg/mL. Kandungan total flavonoid tertinggi terdapat pada daun ketepeng sebesar 26.863 mg/mL, sedangkan kandungan flavonoid terendah terdapat pada daun waru sebesar 1.425 mg/mL. Analisis flavonoid dilakukan pada 𝜆 = 200 - 400 nm dan 𝜆maks = 205 nm. Hasil analisis flavonoid menunjukkan bahwa [A] daun iler panjang gelombang maksimum yaitu 205 nm dan (pita I) 300 nm dan (pita II) 250 nm dengan absorbansi 0.242 positif mengandung flavonol. [B] daun rumput mutiara panjang gelombang maksimum 205 nm dan dapat dilihat pada (pita I) 305 nm dan (pita II) 260 nm dengan absorbansi 0.023 positif mengandung flavonol. [C]) daun ketepeng panjang gelombang maksimum 205 nm dan dapat dilihat pada (pita I) 330 nm dan (pita II) 276 nm dengan absorbansi 0.167 positif mengandung flavonol. [D]) daun pegagan panjang gelombang maksmum 205 nm dan dapat dilihat pada (pita I) 310 nm dan (pita II) 265 nm dengan absorbansi 0.047 positif mengandung flavonol. (E) rumput teki hanya terdapat (I pita) yaitu 295 nm dengan absorbansi 0.029 positif mengandung flavon. (F) Begitupun dengan daun waru hanya terdapat (I pita) yaitu 290 nm dengan absorbansi 0.036 positif mengandung flavon. Dapat disimpulkan bahwa berdasarkan uji kualitatif tanaman iler, ketepeng, rumput mutiara, rumput teki dan pegagan mengandung flavonoid kecuali tanaman waru tidak terdeteksi kandungan flavonoidnya.This studyaims to examine the total flavonoid contentin some traditional medicinal plants. Determination of total flavonoid content swere determined using ethanol-HCl, where as flavonoid analysis was analysed by spectrophotometry UV-VIS.The results showed the total flavonoid contentin Ketepeng China plant (Cassia alataL.) was 26.863 mg/ml, Iler plant (Coleus scutellariodes L. Benth) was 14.2464 mg/ml, nut-grass (Cyperus rotundus L.) was 6.505 mg/ml; Pegagan (Centella asiatica) was 3.816 mg/ml; pearl grass (Oldenlandia corymbosa) was 2.686 mg/ml, and Waru (Hibiscus tiliaceus L.) was 1.425 mg/ml. The highest total flavonoid was found in ketepeng(26.8633mg/ml), whereas the lowest was found in waru (1.4246 mg/ml). Flavonoid analysis was performed using a spectrometer with a wavelength (λ) of 200-400 nm, with λmax = 205 nm. Flavonoid analysis using a spectrophotometer, amon others showed that: (1) The maximum wavelength of Iler leaf was 205 nm and can be see non the Band I 300 nm and Band II 250 nm, with 0.242 absorbance. This indicates that this isolate was positive for flavonols; (2) Maximum wavelength of pearl leaf was 205 nm and can be see non the Band I 305 nm and Band II 260 nm, with 0.023 absorbance. This indicates that this isolate was positive for flavonols; (3) Maximum wavelength of ketepeng leaf was 205 nm and can be see non the Band I 330 nm and Band II 276 nm, with 0.167 absorbance. This indicates that this isolate was positive for flavonols; (4) Maximum wavelength of pegagan leaf was 205 nm and can be see non the Band I 310 nm and Band II 265 nm, with 0.047 absorbance. This indicates that this isolate was positive for flavonols; (5) nut-grass had only 1 band, namely 295 nm with absorbance 0.029. This indcates that this isolate was positive for flavons; (6) waru leaf had also only 1 band, namely 290 nm with absorbance 0.036. This this isolate was positive for flavons.
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Satheesh Kumar D, Shailendra Kumar, and Ravichandran S. "In vitro antidiabetic evaluation of nanoparticles encompass dual bioflavonoid." International Journal of Research in Phytochemistry and Pharmacology 8, no. 1 (July 16, 2020): 1–6. http://dx.doi.org/10.26452/ijrpp.v8i1.1224.
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The flavonoids which are widely spread in plants. It can be categorized as flavonols, flavonols, flavanones, flavones, anthocyanidin and isoflavones. Apigenin and Hesperidin account these three flavonoids used a significant proportion of flavonol intake in the diet as a functional food. Among all other flavonoids, Apigenin has many health cares and disease-prevention benefits. Polymer-based formulations, such as nanoemulsions and solid lipid nanoparticles, have been developed to increase the therapeutic efficacy of flavonoids. New drug delivery systems such as Dual Loaded Flavono Nanoparticulate System (DLFNPs) have not yet been studied with Apigenin and Hesperidin. In the present study, dual loaded flavonol nanoparticulate systems have been developed for oral delivery of Apigenin to enhance its antioxidant and antidiabetic activities. The fabrication of Dual Loaded Flavono Nanoparticles by Nano precipitation technique. Prepared Dual Loaded Flavono polymeric nanoparticles were subjected to characterization and various pharmacological activities. In vitro results revealed that the Alfa amylase percentage of inhibition 33.5% for Nanoparticles Encompass Dual Bioflavonoid by the indication pet ether extracts have lesser activity. This work will be useful for diabetic research workers to be found in the new chemical entity for the treatment of DM and its associated diseases.
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Maslov Bandić, Luna, Milena Jenić, and Boris Duralija. "Bioaktivni spojevi u plodu, listu i sjemenci maline (Rubus idaeus L.)." Glasnik zaštite bilja 43, no. 5 (October 29, 2020): 50–55. http://dx.doi.org/10.31727/gzb.43.5.6.
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Malina (Rubus idaeus L.) jedna je od voćnih vrsta koje su bogate raznolikim kemijskim spojevima kao što su vitamini, minerali i polifenoli. Polifenoli utječu na senzorna i nutritivna svojstva biljke. Listovi i sjemenke maline, koje su većinom nusprodukt proizvodnje imaju značajan sadržaj polifenola, te bi se zajedno s plodovima mogli više koristiti u ljudskoj prehrani kao alternativni izvor bioaktivnih spojeva. U ovom radu određivani su polifenolni spojevi, te je utvrđen sadržaj flavonoida, antocijana i ukupnih fenola u plodu, sjemenci i listu maline sorte 'Himbo Top'. Najveći maseni udio polifenola imale su sjemenke maline, od kojih je izmjereno najviše flavonoida (2853,03 mg/100 g svježeg uzorka) i ukupnih fenola (2369,44 mg/100 g svježeg ploda), a najmanji maseni udio polifenola kod maline imali su plodovi. Također, određen je i antioksidacijski kapacitet pomoću DPPH i ABTS metode, te nisu utvrđene značajne razlike u antioksidacijskom kapacitetu između ploda, lista i sjemenke. Pomoću LC-MS metode identificirani su pojedinačni antocijani i flavonoli u plodu maline.
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Sun, Caihong, Hui Wang, Dong Wang, Yanping Chen, Yan Zhao, and Wei Xia. "Using an FFQ to assess intakes of dietary flavonols and flavones among female adolescents in the Suihua area of northern China." Public Health Nutrition 18, no. 4 (May 6, 2014): 632–39. http://dx.doi.org/10.1017/s1368980014000780.
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AbstractObjectiveThe present study aimed to (i) evaluate the reproducibility and validity of a designed FFQ, (ii) apply the FFQ for estimating the dietary intakes of four flavonols and two flavones in female adolescents and (iii) explain their major dietary sources.DesignThe reproducibility between the first and second FFQ administrations (1 year interval) was estimated using the intra-class correlation coefficient. The validity of the first FFQ relative to the average of four three-day 24 h dietary recalls (24-HR) from four seasons was assessed using the Spearman correlation coefficient. Using a flavonoid content database, the individual flavonol and flavone intakes were calculated and the major food sources were estimated.SettingMiddle school in Suihua area of Heilongjiang Province, northern China.SubjectsFemale adolescents (n 887) aged 12–18 years.ResultsBetter reproducibility and validity were obtained in the present study. The flavonol and flavone intakes were 16·29 and 4·31 mg/d, respectively. Quercetin and kaempferol were the major contributors (26·8 % and 23·7 %, respectively) to the total intake of flavonols and flavones. The main food sources of flavonols and flavones were apples (14·1 %), followed by potatoes (7·5 %), lettuce (7·3 %) and oranges (7·3 %).ConclusionsThe dietary flavonol and flavone intakes among female adolescents in northern China were similar to those reported in several countries, but significant differences were observed in the food sources ascribed to the geographical location and dietary characteristics.
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Nikolova, M., and S. Ivancheva. "Distribution of Surface Flavonoids in Bulgarian Plants." Natural Product Communications 1, no. 11 (November 2006): 1934578X0600101. http://dx.doi.org/10.1177/1934578x0600101119.
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The review describes the distribution of surface flavonoids in Bulgarian plants. More than 100 species of Asteraceae, Lamiaceae, Scrophulariaceae, Geraniaceae and other families have been checked for external flavonoid aglycones. The flavonoid profiles of Asteraceae species are composed of a wide array of flavones and flavonols, mainly based upon 6-substituted derivatives. Flavone aglycones are predominant in the exudates of Lamiaceae species. Apigenin, luteolin and their derivatives were most commonly found in the studied species of Scropulariaceae and Lamiaceae. It has been shown that species of Geraniaceae, Ranunculaceae, and Solanaceae contain flavonoids of the flavonol class as surface constituents. Surface distributed flavonoids appear to have been well studied and useful for chemotaxonomy. If there is not too much infraspecific variation, flavonoid profiles can be used as taxonomic characters to distinguish species. Correlations between external flavonoid formation and local environment are apparent.
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Wang, Lanxiang, Pui Ying Lam, Andy C. W. Lui, Fu-Yuan Zhu, Mo-Xian Chen, Hongjia Liu, Jianhua Zhang, and Clive Lo. "Flavonoids are indispensable for complete male fertility in rice." Journal of Experimental Botany 71, no. 16 (May 9, 2020): 4715–28. http://dx.doi.org/10.1093/jxb/eraa204.
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Abstract Flavonoids are essential for male fertility in some but not all plant species. In rice (Oryza sativa), the chalcone synthase mutant oschs1 produces flavonoid-depleted pollen and is male sterile. The mutant pollen grains are viable with normal structure, but they display reduced germination rate and pollen-tube length. Analysis of oschs1/+ heterozygous lines shows that pollen flavonoid deposition is a paternal effect and fertility is independent of the haploid genotypes (OsCHS1 or oschs1). To understand which classes of flavonoids are involved in male fertility, we conducted detailed analysis of rice mutants for branch-point enzymes of the downstream flavonoid pathways, including flavanone 3-hydroxylase (OsF3H; flavonol pathway entry enzyme), flavone synthase II (CYP93G1; flavone pathway entry enzyme), and flavanone 2-hydroxylase (CYP93G2; flavone C-glycoside pathway entry enzyme). Rice osf3h and cyp93g1 cyp93g2 CRISPR/Cas9 mutants, and cyp93g1 and cyp93g2 T-DNA insertion mutants showed altered flavonoid profiles in anthers, but only the osf3h and cyp93g1 cyp93g2 mutants displayed reduction in seed yield. Our findings indicate that flavonoids are essential for complete male fertility in rice and a combination of different classes (flavanones, flavonols, flavones, and flavone C-glycosides) appears to be important, as opposed to the essential role played primarily by flavonols that has been previously reported in several plant species.
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Kyle, Janet A. M., Linda Sharp, Julian Little, Garry G. Duthie, and Geraldine McNeill. "Dietary flavonoid intake and colorectal cancer: a case–control study." British Journal of Nutrition 103, no. 3 (September 7, 2009): 429–36. http://dx.doi.org/10.1017/s0007114509991784.
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Diets rich in flavonoids may reduce the risk of developing colorectal cancer. Flavonoids are widely distributed in foods of plant origin, though in the UK tea is the main dietary source. Our objective was to evaluate any independent associations of total dietary and non-tea intake of four flavonoid subclasses and the risk of developing colorectal cancer in a tea-drinking population with a high colorectal cancer incidence. A population-based case–control study (264 cases with histologically confirmed incident colorectal cancer and 408 controls) was carried out. Dietary data gathered by FFQ were used to calculate flavonoid intake. Adjusted OR and 95 % CI were estimated by logistic regression. No linear association between risk of developing colorectal cancer and total dietary flavonol, procyanidin, flavon-3-ol or flavanone intakes was found, but non-tea flavonol intake was inversely associated with colorectal cancer risk (OR 0·6; 95 % CI 0·4, 1·0). Stratification by site of cancer and assessment of individual flavonols showed a reduced risk of developing colon but not rectal cancer with increasing non-tea quercetin intake (OR 0·5; 95 % CI 0·3, 0·8; Ptrend < 0·01). We concluded that flavonols, specifically quercetin, obtained from non-tea components of the diet may be linked with reduced risk of developing colon cancer.
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Wang, Qianchao, Lan Yao, Qunying Li, Heng Xie, Yirui Guo, Tingzhi Huang, Xuesong Zhang, et al. "Integrative Analysis of the Metabolome and Transcriptome Provides Insights into the Mechanisms of Flavonoid Biosynthesis in Quinoa Seeds at Different Developmental Stages." Metabolites 12, no. 10 (September 22, 2022): 887. http://dx.doi.org/10.3390/metabo12100887.
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Quinoa (Chenopodium quinoa Willd.) is a crop with high nutritional and health benefits. Quinoa seeds are rich in flavonoid compounds; however, the mechanisms behind quinoa flavonoid biosynthesis remain unclear. We independently selected the high-generation quinoa strain ‘Dianli-3260′, and used its seeds at the filling, milk ripening, wax ripening, and mature stages for extensive targeted metabolome analysis combined with joint transcriptome analysis. The results showed that the molecular mechanism of flavonoid biosynthesis in quinoa seeds was mainly concentrated in two pathways: “flavonoid biosynthesis pathway” and “flavone and flavonol biosynthesis pathway”. Totally, 154 flavonoid-related metabolites, mainly flavones and flavonols, were detected in the four development stages. Moreover, 39,738 genes were annotated with KEGG functions, and most structural genes of flavonoid biosynthesis were differentially expressed during grain development. We analyzed the differential flavonoid metabolites and transcriptome changes between the four development stages of quinoa seeds and found that 11 differential flavonoid metabolites and 22 differential genes were the key factors for the difference in flavonoid biosynthesis. This study provides important information on the mechanisms underlying quinoa flavonoid biosynthesis, the screening of potential quinoa flavonoid biosynthesis regulation target genes, and the development of quinoa products.
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Dewi, Ni Wayan Rika Kumara, I. Wayan Gunawan, and Ni Made Puspawati. "ISOLASI DAN IDENTIFIKASI SENYAWA ANTIOKSIDAN GOLONGAN FLAVONOID DARI EKSTRAK ETIL ASETAT DAUN PRANAJIWA (Euchresta horsfieldii Lesch Benn.)." CAKRA KIMIA (Indonesian E-Journal of Applied Chemistry) 5, no. 1 (July 28, 2017): 26. http://dx.doi.org/10.24843/ck.2017.v05.i01.p04.
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ABSTRAK: Penelitian ini bertujuan untuk menentukan aktivitas antioksidan dan mengidentifikasi senyawa golongan flavonoid yang terkandung dalam ekstrak etil asetat daun pranajiwa (Euchresta horsfieldii Lesch Benn.). Uji aktivitas antioksidan dilakukan secara invitro dengan metode DPPH (1,1-diphenyl-2-pycrylhidrazyl). Teknik pemisahan dilakukan dengan kromatografi kolom dan diidentifikasi dengan spektrofotometer FTIR dan UV-Vis. Hasil penelitian menunjukkan bahwa ekstrak etil asetat memiliki aktivitas antioksidan dengan nilai IC50 sebesar 393,95 µg/mL dan kadar total flavonoid sebesar 6619,72 mg QE/100g atau 6,62 % QE. Pemisahan dan pemurnian ekstrak etil asetat menggunakan fase diam silika gel 60 dan fase gerak n-heksana:kloroform: etanol (20:1:1) yang menghasilkan isolat aktif yang positif flavonoid (isolat FE) yang diduga merupakan senyawa flavonoid golongan flavonol yaitu 3,5,7,3’,4’-pentahidroksi flavonol.
ABSTRACT: The present study was conducted to determine antioxidant activity and to identify the flavonoid active compounds from ethyl acetate extracts of Pranajiwa leaves. In vitro antioxidant activity was carried out using DPPH (1,1-diphenyl-2-pycrylhidrazyl) method. The separation of the ethyl acetate extracts was conducted by column chromatography and the identification by using FTIR and UV-Vis spectrophotometer. The results showed that ethyl acetate extract has antioxidant activity with IC50 value of 393,95 µg/mL and the total flavonoid of 6619,72 mg QE /100g or 6,62% QE. The separation and purification of ethyl acetate extract was chromatography column on silica gel 60 and the solvent n-hexane:chloroform:ethanol (20:1:1) based on UV-Vis and Infrared spectra positive flavonoid isolate (isolates FE) was tentaviely identified as 3,5,7,3',4'-pentadihydroxy flavonols.
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Johnson, Emanuel L., and Walter F. Schmidt. "Flavonoids as Chemotaxonomic Markers for Erythroxylum ulei." Zeitschrift für Naturforschung C 54, no. 11 (November 1, 1999): 881–88. http://dx.doi.org/10.1515/znc-1999-1105.
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Abstract Leaf extracts of Erythroxylum ulei O. E. Schulz, produced six O-conjugated flavonoids. Three of the flavonoid aglycones were isoflavones, two were isoflavanones and the remainder a flavonol (quercetin). The major glycosides of these flavonols included mono-and dirham-nosides, mono-glucosides and galactosides with either 3̕ 4̕, or 7 linkage or a combination thereof. The two isoflavanones, in addition to being glycosylated, possessed a methyl group at position 2 of the C-ring. These flavonoids may be used as chemotaxonomic markers for the taxon.
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Dangrit, Darin, and Kanokporn Sompornpailin. "Enhancing Biosynthesis of Flavonol Protective Biomaterials Using FLS Transgenic Plants." Applied Mechanics and Materials 866 (June 2017): 29–32. http://dx.doi.org/10.4028/www.scientific.net/amm.866.29.
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Flavonol synthase (FLS) gene encodes an enzyme that is involved in conversion substrates into flavonols, quercetin and kaempferol. These substances are a subgroup of flavonoids which have an important role in both plant and human health. Many environmental factors such as temperature, pH and UV-A radiation have been studied and presented relationship with flavonoid synthesis. In this experiment, the combination of visible and UV-A lights was used as factors for elevating flavonoid biosynthesis of wild type (WT) plant and two lines of FLS transgenic plant under tissue culture condition. Both transgenic lines significantly enhanced the accumulation of quercetin and kaempferol substances nearly one fold higher than WT plant did. The photosynthetic pigment levels of chlorophyll A, chlorophyll B and carotenoid in transgenic lines are in the range 45.20-46.88, 16.34-17.04 and 13.63-13.46, while those of WT plants are 35.93, 13.18 and 10.55 (µg/g FW), respectively. Therefore, FLS transgenic plants containing high flavonol content showed a better in the protection photosynthetic pigments by less reductions of chlorophyll and carotenoid pigments.
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Kozłowska, Aleksandra, and Dorota Szostak-Węgierek. "Targeting Cardiovascular Diseases by Flavonols: An Update." Nutrients 14, no. 7 (March 30, 2022): 1439. http://dx.doi.org/10.3390/nu14071439.
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Flavonols are one of the most plentiful flavonoid subclasses found in natural products and are extensively used as dietary supplements. Numerous in vitro and in vivo studies have shown the cardioprotective properties of flavonols, especially quercetin. This group of substances exerts positive impacts primarily due to their antiatherogenic, antithrombotic, and antioxidant activities. The potential of flavonols to promote vasodilation and regulation of apoptotic processes in the endothelium are other beneficial effects on the cardiovascular system. Despite promising experimental findings, randomized controlled trials and meta-analyses have yielded inconsistent results on the influence of these substances on human cardiovascular parameters. Thus, this review aims to summarize the most recent clinical data on the intake of these substances and their effects on the cardiovascular system. The present study will help clinicians and other healthcare workers understand the value of flavonol supplementation in both subjects at risk for cardiovascular disease and patients with cardiovascular diseases.
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Zhang, Haiwen, Huihui Tao, Hao Yang, Liuzi Zhang, Guizhi Feng, Yuyan An, and Liangju Wang. "MdSCL8 as a Negative Regulator Participates in ALA-Induced FLS1 to Promote Flavonol Accumulation in Apples." International Journal of Molecular Sciences 23, no. 4 (February 12, 2022): 2033. http://dx.doi.org/10.3390/ijms23042033.
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Apples (Malus domestica) are rich in flavonols, and 5-aminolevulinic acid (ALA) plays an important role in the regulation of plant flavonoid metabolism. To date, the underlying mechanism of ALA promoting flavonol accumulation is unclear. Flavonol synthase (FLS) is a key enzyme in flavonol biosynthesis. In this study, we found that ALA could enhance the promoter activity of MdFLS1 in the ‘Fuji’ apple and improve its expression. With MdFLS1 as bait, we screened a novel transcription factor MdSCL8 by the Yeast One-Hybrid (Y1H) system from the apple cDNA library which we previously constructed. Using luciferase reporter assay and transient GUS activity assay, we verified that MdSCL8 inhibits the activity of MdFLS1 promoter and hinders MdFLS1 expression, thus reducing flavonol accumulation in apple. ALA significantly inhibited MdSCL8 expression. Therefore, ALA promoted the expression of MdFLS1 and the consequent flavonol accumulation probably by down-regulating MdSCL8. We also found that ALA significantly enhanced the gene expression of MdMYB22 and MdHY5, two positive regulators of MdFLS. We further demonstrated that MdMYB22 interacts with MdHY5, but neither of them interacts with MdSCL8. Taken together, our data suggest MdSCL8 as a novel regulator of MdFLS1 and provide important insights into mechanisms of ALA-induced flavonol accumulation in apples.
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Valant-Vetschera, Karin M., and Eckhard Wollenweber. "Chemodiversity of Exudate Flavonoids in Seven Tribes of Cichorioideae and Asteroideae (Asteraceae)." Zeitschrift für Naturforschung C 62, no. 3-4 (April 1, 2007): 155–63. http://dx.doi.org/10.1515/znc-2007-3-401.
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Abstract Members of several genera of Asteraceae, belonging to the tribes Mutisieae, Cardueae, Lactuceae (all subfamily Cichorioideae), and of Astereae, Senecioneae, Helenieae and Heliantheae (all subfamily Asteroideae) have been analyzed for chemodiversity of their exudate flavonoid profiles. The majority of structures found were flavones and flavonols, sometimes with 6- and/or 8-substitution, and with a varying degree of oxidation and methylation. Flavanones were observed in exudates of some genera, and, in some cases, also flavonol- and flavone glycosides were detected. This was mostly the case when exudates were poor both in yield and chemical complexity. Structurally diverse profiles are found particularly within Astereae and Heliantheae. The tribes in the subfamily Cichorioideae exhibited less complex flavonoid profiles. Current results are compared to literature data, and botanical information is included on the studied taxa.
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Karapandzova, Marija, Gjose Stefkov, Ivana Cvetkovikj, Jasmina Petreska Stanoeva, Marina Stefova, and Svetlana Kulevanova. "Flavonoids and Other Phenolic Compounds in Needles of Pinus peuce and Other Pine Species from the Macedonian Flora." Natural Product Communications 10, no. 6 (June 2015): 1934578X1501000. http://dx.doi.org/10.1177/1934578x1501000647.
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Flavonoids and other phenolic compounds in young needles of four pine species, Pinus peuce, P. nigra, P. mugo and P. sylvestris from the Macedonian flora were investigated. The amount of total phenols and total flavonoids were determined using Folin-Ciocalteau and aluminum chloride assay, respectively. The obtained results revealed that the total phenolic content (TPC) and total flavonoids content (TFC) varied among different pine species ranging from 9.8 to 14.0 mg GAE/g and from 3.3 to 7.2 mg CE/g of dried plant material, respectively. Qualitative analysis of flavonoids and other phenolic components was made by a LC-DAD/ESI-MSn optimized chromatographic method. A total of 17 phenolic components were identified and classified as: acids (2), procyanidins (2) and flavonoid glycosides (13). The most prevalent components were flavonoid glycosides, especially flavonols and methylated flavonols (9). Additionally, 3 components were found as acylated flavonol glycosides with ferulic and p-coumaric acid. The last one was found not only in esterified form but also in the free form. Only one flavone-apigenin glycoside was detected. Procyanidins were identified as catechin derivatives, both dimers and trimers.
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Yang, Ming-hua, and Ling-yi Kong. "Flavonols and flavonol glycosides from Rhododendron irroratum." Chemistry of Natural Compounds 44, no. 1 (January 2008): 98–99. http://dx.doi.org/10.1007/s10600-008-0028-6.
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Zhou, Yanjun, Ke Gu, and Fengying Zhou. "Dietary Flavonoid Intake and Cancer Mortality: A Population-Based Cohort Study." Nutrients 15, no. 4 (February 15, 2023): 976. http://dx.doi.org/10.3390/nu15040976.
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Cancer is a leading cause of death worldwide, posing a huge burden upon society and individuals. The adequate intake of fruit and vegetables is reported to be an effective strategy for primary cancer prevention. Fruits and vegetables are rich in nutrients, such as vitamins and flavonoids, which may reduce the occurrence and progression of cancers. However, the importance of each flavonoid and the sub-classes remains controversial regarding cancer mortality. The population benefiting from increased flavonoid intake has not been determined. An estimation of cancer mortality by flavonoid intake is not established. We explored the association between the intake of flavonoids and cancer mortality amongst 14,029 participants in the National Health and Nutrition Examination Survey. During a median follow-up of 117 months, 405 cancer deaths were confirmed. Being in the second, third, and fourth quartiles of flavonol intake, the cancer mortality was inversely associated with the intake of flavonols (multivariate analysis HR (95% CI] 0.58 [0.36, 0.91], p = 0.02, Q1 vs. Q2; 0.55 [0.31, 0.96], p = 0.04, Q1 vs. Q3; 0.54 [0.30, 0.99], p = 0.05, Q1 vs. Q4, respectively). Potential effects of dietary flavonol intake against cancer death was observed especially in participants aged 50 or above, males, whites, former smokers, people who used to drink or drink alcohol mildly, people without hyperlipidemia, and people with hypertension. Moreover, the dietary intakes of peonidin, naringenin, and catechin were inversely associated with cancer mortality (multivariate HR [95% CI] 0.93 [0.88,0.98], p = 0.01; 0.97(0.95,1.00), p = 0.03; 0.98(0.96,1.00), p = 0.05, respectively). Furthermore, a nomogram based on flavonol intake is feasible for assessing cancer mortality for each participant. Taken together, our results could improve personalized nutrition amongst cancer patients.
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Gao, Gang, Ping Chen, Jikang Chen, Kunmei Chen, Xiaofei Wang, Aminu Shehu Abubakar, Ning Liu, Chunming Yu, and Aiguo Zhu. "Genomic Survey, Transcriptome, and Metabolome Analysis of Apocynum venetum and Apocynum hendersonii to Reveal Major Flavonoid Biosynthesis Pathways." Metabolites 9, no. 12 (December 5, 2019): 296. http://dx.doi.org/10.3390/metabo9120296.
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Apocynum plants, especially A. venetum and A. hendersonii, are rich in flavonoids. In the present study, a whole genome survey of the two species was initially carried out to optimize the flavonoid biosynthesis-correlated gene mining. Then, the metabolome and transcriptome analyses were combined to elucidate the flavonoid biosynthesis pathways. Both species have small genome sizes of 232.80 Mb (A. venetum) and 233.74 Mb (A. hendersonii) and showed similar metabolite profiles with flavonols being the main differentiated flavonoids between the two specie. Positive correlation of gene expression levels (flavonone-3 hydroxylase, anthocyanidin reductase, and flavonoid 3-O-glucosyltransferase) and total flavonoid content were observed. The contents of quercitrin, hyperoside, and total anthocyanin in A. venetum were found to be much higher than in A. hendersonii, and such was thought to be the reason for the morphological difference in color of A. venetum and A. hendersonii. This study provides valuable genomic and metabolome information for understanding of A. venetum and A. hendersonii, and lays a foundation for elucidating Apocynum genus plant flavonoid biosynthesis.
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Guo, Xiaozhu, Gui Wang, Juan Li, Jiang Li, and Xuemei Sun. "Analysis of Floral Color Differences between Different Ecological Conditions of Clematis tangutica (Maxim.) Korsh." Molecules 28, no. 1 (January 3, 2023): 462. http://dx.doi.org/10.3390/molecules28010462.
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The Clematis tangutica (Maxim.) Korsh. is a wild flowering plant that is most widely distributed on the Qinghai–Tibet Plateau, with beautiful, brightly colored flowers and good ornamental properties and adaptability. In diverse natural environments, the blossom color of C. tangutica (Maxim.) Korsh. varies greatly, although it is unclear what causes this diversity. It was examined using UPLC-MS/MS and transcriptome sequencing for the investigation of various compounds, differentially expressed genes (DEGs), and flavonoid biosynthesis-related pathways in two flowers in two ecological settings. The results showed that a total of 992 metabolites were detected, of which 425 were differential metabolites, mainly flavonoid metabolites associated with its floral color. The most abundant flavonoids, flavonols and anthocyanin metabolites in the G type were cynaroside, isoquercitrin and peonidin-3-O-glucoside, respectively. Flavonoids that differed in multiplicity in G type and N type were rhoifolin, naringin, delphinidin-3-O-rutinoside, chrysoeriol and catechin. Rhoifolin and chrysoeriol, produced in flavone and flavonol biosynthesis, two flavonoid compounds of C. tangutica (Maxim.) Korsh. with the largest difference in floral composition in two ecological environments. In two ecological environments of flower color components, combined transcriptome and metabolome analyses revealed that BZ1-1 and FG3-1 are key genes for delphinidin-3-O-rutinoside in anthocyanin biosynthesis, and HCT-5 and FG3-3 are key genes for rhoifolin and naringin in flavonoid biosynthesis and flavone and flavonol. Key genes for chlorogenic acid in flavonoid biosynthesis include HCT-6, CHS-1 and IF7MAT-1. In summary, differences in flavonoids and their content are the main factors responsible for the differences in the floral color composition of C. tangutica (Maxim.) Korsh. in the two ecological environments, and are associated with differential expression of genes related to flavonoid synthesis.
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Stich, K., T. Eidenberger, F. Wurst, and G. Forkmann. "Flavonol Synthase Activity and the Regulation of Flavonol and Anthocyanin Biosynthesis during Flower Development in Dianthus caryophyllus L. (Carnation)." Zeitschrift für Naturforschung C 47, no. 7-8 (August 1, 1992): 553–60. http://dx.doi.org/10.1515/znc-1992-7-811.
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Flavonol synthase (FLS) was demonstrated in crude extracts from flower buds of Dianthus caryophyllus (carnation). The enzyme catalyzed the conversion of dihydrokaempferol and ihydroquercetin to kaempferol and quercetin, respectively. The reaction required 2-oxoglutarate, ferrous ion and ascorbate as co-factors and had a pH optimum at about 7.4. The demonstration of FLS activity allowed comparative studies on flavonol and anthocyanin biosynthesis during bud and flower development. Besides FLS the flavonoid enzymes chalcone synthase (CHS), flavanone 3-hydroxylase (FH T) and dihydroflavonol 4-reductase (DFR) were measured. DFR is specifically involved in anthocyanin synthesis, while CHS and FHT provide dihydroflavonol, the common substrate for both FLS and DFR . Maximum expression of CHS, FHT and FLS activity was already observed in small buds, whereas DFR activity started to increase much later and reached its highest level in opened flowers. A substantial correlation was observed between the time courses of FLS and DFR activity and the accumulation of flavonols and anthocyanins, respectively. The competition of FLS and DFR for dihydroflavonols was found to be largely circumvented by different substrate specificities and by the sequential expression of the two enzymes. Both flavonols and anthocyanins are obviously not, or only to some extent, subject to degradation.
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Tine, Yoro, Yin Yang, Franck Renucci, Jean Costa, Alassane Wélé, and Julien Paolini. "LC-MS/MS Analysis of Flavonoid Compounds from Zanthoxylum zanthoxyloides Extracts and Their Antioxidant Activities." Natural Product Communications 12, no. 12 (December 2017): 1934578X1701201. http://dx.doi.org/10.1177/1934578x1701201213.
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Flavonoids are a large group of phenolic secondary metabolites having a wide range of biochemical and pharmacological effects. In this work, a targeted liquid chromatography (LC) coupled with tandem mass spectrometry (MS2) was used to characterize the flavonoid compositions of methanolic plant extracts from separated parts (fruits, leaves, stems, trunk barks, and root barks) of Zanthoxylum zanthoxyloides. Nine flavonoids were reported in this species, including three flavanones, five flavonols and one flavone. Quantitative analysis of flavonoid profiles from Z. zanthoxyloides extracts is useful to a better understanding of the pattern and distribution of metabolites in extract samples. The concentrations of two glycosylated flavanones (neohesperidin and hesperidin) and one flavonol (quercetin) were higher in root and trunk samples compared to fruit samples. These compounds were reported in small amounts in the stem and leaf samples. In contrast, four flavonols (hyperoside, quercetin-3- O-glucopyranoside, datiscin and quercitrin) were present in significant levels only in the leaf extracts. The presence of glycosylated flavanone (eriocitrin) has been reported only in fruit extract. The antioxidant properties of different extracts were tested regarding their scavenging activities on ABTS•+ radical. Leaf and trunk bark extracts exhibited antioxidant activities, while the extracts obtained from other organs (fruits, stems, and root barks) showed low antioxidant properties.
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Xue, Rasmussen, and G. Lane. "Cold stress in white clover - An integrated view of metabolome and transcriptome responses." NZGA: Research and Practice Series 12 (January 1, 2006): 35–40. http://dx.doi.org/10.33584/rps.12.2006.3044.
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We have studied metabolic and gene expression responses of two white clover genotypes differing in foliar basal flavonol and anthocyanin levels subjected to moderate cold in a controlled climate chamber experiment. The main flavonols and anthocyanins accumulating in white clover leaves are conjugated to galactose and xylose. Concentrations of flavonoids and sugars including starch significantly increased during cold treatment and a strong induction of flavonoid pathway genes was observed in both genotypes. Specific sugars like glucose, fructose, and starch were significantly higher in the genotype with low basal flavonoid levels. By combining metabolic and gene expression analysis we have identified two genes probably involved in the conjugation and deconjugation of flavonoids, a flavonoid galactosyltransferase and a β- galactosidase. The selected flavonoid galactosyltransferase was up-regulated by cold treatment and was also expressed at higher levels in the red leaved genotype. The β- galactosidase studied here was down-regulated by cold and expressed less in the red leaved genotype. These results indicate a tight link between primary and secondary metabolism in clover and demonstrate the value of combined metabolome and transcriptome analysis for the identification of specific gene functions.
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Wang, Tao, Fengjiao Zhang, Weibing Zhuang, Xiaochun Shu, and Zhong Wang. "Metabolic Variations of Flavonoids in Leaves of T. media and T. mairei Obtained by UPLC-ESI-MS/MS." Molecules 24, no. 18 (September 12, 2019): 3323. http://dx.doi.org/10.3390/molecules24183323.
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The needles of Taxus species contain a large number of bioactive compounds, such as flavonoids. In the present study, the total flavonoid content in leaves of Taxus media and Taxus mairei was 19.953 and 14.464 mg/g, respectively. A total of 197 flavonoid metabolites (70 flavones, 42 flavonols, 26 flavone C-glycosides, 20 flavanones, 15 anthocyanins, 13 isoflavones, 6 flavonolignans, and 5 proanthocyanidins) were identified for the first time by a widely targeted Ultra Performance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry (UPLC-ESI-MS/MS) method within the two Taxus species, containing 160 common metabolites, with 37 unique metabolites merely determined in T. mairei or T. media. Moreover, 42 differential flavonoid metabolites were screened in the two Taxus species, which showed specific metabolic patterns in isoflavonoid biosynthesis, anthocyanin biosynthesis, and flavone and flavonol biosynthesis pathways. Compared to T. mairei, a more activated phenylpropanoid pathway was found in T. media, which could be responsible for the higher content of total flavonoids in T. media. Our results provide new insights into the diversity of flavonoid metabolites between T. mairei and T. media, and provide a theoretical basis for the sufficient utilization of Taxus species and the development of novel drugs.
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Rafieian-Kopaei, Mahmoud, Reyhaneh Eskandarian, Elham Bijad, Majid Banitalebi, and Mohammad Rahimi-Madiseh. "In vitro evaluation of the amount of flavonoids, flavanols, and total phenolic compounds in 10 medicinal plants used in Iran; focus on diabetes and kidney diseases." Journal of Renal Endocrinology 8 (January 1, 2022): e21068. http://dx.doi.org/10.34172/jre.2022.21068.
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Introduction: Free radicals and reactive oxygen species (ROS) as oxidants are important concerns in medicine due to their adversative effects and risk of carcinogenicity. Antioxidants can neutralize free radicals and ROS thus possesses protective effect on the body. Plants are rich sources of natural antioxidants and phenolic compounds are among the most important antioxidants in the plants; therefore, many studies have investigated their protective effects. Objectives: This study was conducted to evaluate and compare the number of flavonoids, flavonols, and total phenolic compounds in 10 commonly used medicinal plants in Iran. Materials and Methods: Extraction was performed using 70% ethanol solvent. The extracts were concentrated by rotary evaporator at 40°C. Folin-Ciocalteu method was used to measure the amount of phenol. The amount of flavonol was measured using 2% aluminum chloride and 5% sodium acetate. In addition, to determine the flavonoid compounds, 2% aluminum chloride and 5% potassium acetate was used. Results: The outcomes of this study disclosed that the studied plants had reasonably high quantities of flavonoid and phenolic compounds. The uppermost amount of phenolic compounds was detected in the myrtle plant (62.7 mg/g), and the lowermost amounts were detected in fig leaves and lemon balm. Moreover, the highest amount of flavonoid compounds was detected in ginger, myrobalan, and myrtle; the measured amounts of flavonoid compounds in the mentioned plants were 42.49, 32.15, and 34.38 mg/g, respectively. The highest amount of phenolic compound was detected in hydroalcoholic extract of barberry. Conclusion: Hydroalcoholic extract of ginger, barberry, fig leaves, rhubarb, myrobalan, walnut diaphragm, pomegranate peel, lemon balm, cardamom, and myrtle had great quantities of phenolic, flavonol, and flavonoid compounds. As a result, these herbal plants can be considered and used as an important source of natural antioxidants.
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Jeganathan, Brasathe, P. A. Nimal Punyasiri, J. Dananjaya Kottawa-Arachchi, Mahasen A. B. Ranatunga, I. Sarath B. Abeysinghe, M. T. Kumudini Gunasekare, and B. M. Ratnayake Bandara. "Genetic Variation of Flavonols Quercetin, Myricetin, and Kaempferol in the Sri Lankan Tea (Camellia sinensisL.) and Their Health-Promoting Aspects." International Journal of Food Science 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/6057434.
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Flavonol glycosides in tea leaves have been quantified as aglycones, quercetin, myricetin, and kaempferol. Occurrence of the said compounds was reported in fruits and vegetable for a long time in association with the antioxidant potential. However, data on flavonols in tea were scanty and, hence, this study aims to envisage the flavonol content in a representative pool of accessions present in the Sri Lankan tea germplasm. Significant amounts of myricetin, quercetin, and kaempferol have been detected in the beverage type tea accessions of the Sri Lankan tea germplasm. This study also revealed that tea is a good source of flavonol glycosides. TheCamellia sinensisvar.sinensisshowed higher content of myricetin, quercetin, and total flavonols than var.assamicaand ssp.lasiocalyx. Therefore flavonols and their glycosides can potentially be used in chemotaxonomic studies of tea germplasm. The nonbeverage type cultivars, especiallyCamellia rosafloraandCamellia japonicaRed along with the exotic accessions resembling China type, could be useful in future germplasm studies because they are rich sources of flavonols, namely, quercetin and kaempferol, which are potent antioxidants. The flavonol profiles can be effectively used in choosing parents in tea breeding programmes to generate progenies with a wide range of flavonol glycosides.
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Tahir, Iqmal, Mohd Noor Ahmad, AKM Shafiqul Islam, and Dachyar Arbain. "VIRTUAL SEARCHING OF DUMMY TEMPLATE FOR SINENSETIN BASED ON 2D MOLECULAR SIMILARITY USING CHEMDB TOOL." Indonesian Journal of Chemistry 12, no. 3 (December 28, 2012): 217–22. http://dx.doi.org/10.22146/ijc.21333.
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Sinensetin-like molecules have been searched virtually to find a dummy template for Molecular Imprinted Polymer (MIP) synthesis. The aim of this study is to find a novel adsorbent for Solid Phase Extraction (SPE) of sinensetin based on tailored method using dummy template. Virtual searching was done using ChemDB online chemical database containing 5 million commercially available chemicals. Sinensetin as target was converted into SMILES code then it was run with threshold of molecular similarity score of 0.5. There were 90 chemical structures given as the output mainly flavone analogue, three flavonols and several non-flavonoid compounds. The suggested results are three dummy templates that derived from luteolin (flavon) or quercetin (flavonol) with slight alteration by methoxylation process.
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Su, Mengyue, Rebecca Njeri Damaris, Zhengrong Hu, Pingfang Yang, and Jiao Deng. "Metabolomic Analysis on the Petal of ‘Chen Xi’ Rose with Light-Induced Color Changes." Plants 10, no. 10 (September 30, 2021): 2065. http://dx.doi.org/10.3390/plants10102065.
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Flower color is one of the most prominent traits of rose flowers and determines their ornamental value. The color of the “Chen Xi” rose can change from yellow to red during flower blooming. In the present study, the flavonoid metabolites were investigated by the UPLC-ESI-MS/MS from the petals of four successive flower development stages under natural conditions. In total, 176 flavonoid components, including 49 flavones, 59 flavonols, 12 flavanones, 3 isoflavones, 12 anthocyanins, and 41 proanthocyanidins were identified, with some of them being detected for the first time in this study. Additionally, there were 56 compounds that showed differences among comparison groups, mainly being enriched in pathways of isoflavone, flavonoid, flavone, flavonol, phenylpropanoids, and anthocyanin. Among them, it is anthocyanins that allow the rose flower to turn red when exposed to sunlight. To verify this result, compounds from rose petal with shading treatment (S2D) was also detected but could be clearly separated from the four samples under light by clustering and principal component analyses (PCA). Consistent with low anthocyanins accumulation, the flower with shading could not turn red. Moreover, it provides a foundation for further research on the light-induced color modification of flower.
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Kostikova, Vera A., and Tatiana N. Veklich. "HPLC analysis of phenolic compounds in leaves and inflorescences of Sorbaria pallasii." BIO Web of Conferences 24 (2020): 00040. http://dx.doi.org/10.1051/bioconf/20202400040.
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At least 22 phenolic compounds were identified in aqueous-ethanol extracts from Sorbaria pallasii (G. Don fil.) Pojark. leaves and at least 28 in its inflorescences by High-Performance Liquid Chromatography. Two acids (chlorogenic and p-hydroxybenzoic) and five flavonols (hyperoside, isoquercitrin, quercitrin, kaempferol, and astragalin) were identified among them. Flavonoid aglycones were obtained from the leaves and inflorescences by hydrochloric-acid hydrolysis of the aqueous-ethanol extracts (1:1). Three flavonol aglycones (quercetin, kaempferol, and isorhamnetin) were identified in the extract hydrolysates from S. pallasii above-ground organs through chromatographic analysis. Additionally, a flavone aglycone (luteolin) was found in the extract hydrolysates from the leaves. Kaempferol glycosides are predominant phenolic compounds in S. pallasii inflorescences, and quercetin glycosides in its leaves.
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Iwashina, Tsukasa, Minoru N. Tamura, Yoshinori Murai, and Junichi Kitajima. "New Flavonol Glycosides from the Leaves of Triantha Japonica and Tofieldia Nuda." Natural Product Communications 8, no. 9 (September 2013): 1934578X1300800. http://dx.doi.org/10.1177/1934578x1300800917.
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Two new flavonol glycosides were isolated from the leaves of Triantha japonica, together with eight known flavonols, kaempferol 3- O-sophoroside, kaempferol 3- O-sambubioside, kaempferol 3- O-glucosyl-(1→2)-[glucosyl-(1→6)-glucoside], quercetin 3- O-sophoroside, quercetin 3- O-sambubioside, isorhamnetin 3- O-glucoside, isorhamnetin 3- O-sophoroside and isorhamnetin 3- O-sambubioside. The new compounds were identified as kaempferol 3- O-β-xylopyranosyl-(1→2)-[β-glucopyranosyl-(1→6)-β-glucopyranoside] (1) and isorhamnetin 3- O-β-xylopyranosyl-(1→2)-[β-glucopyranosyl-(1→6)-β-glucopyranoside] (3) by UV, LC-MS, acid hydrolysis, and 1H and 13C NMR spectroscopy. Another two new flavonol glycosides were isolated from the leaves of Tofieldia nuda, and identified as kaempferol 3- O-β-glucopyranosyl-(1→2)-[β-glucopyranosyl-(1→6)-β-galactopyranoside] (4) and quercetin 3- O-β-glucopyranosyl-(1→2)-[β-glucopyranosyl-(1→6)-β-galactopyranoside] (5). Though the genera Triantha and Tofieldia were treated as Tofieldia sensu lato, they were recently divided into two genera. It was shown by this survey that their flavonoid composition were also different to each other.
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Graham, Terrence L. "Flavonoid and flavonol glycoside metabolism in Arabidopsis." Plant Physiology and Biochemistry 36, no. 1-2 (January 1998): 135–44. http://dx.doi.org/10.1016/s0981-9428(98)80098-3.
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Onayemi, Olanike O., Catherine C. Neto, and Justine E. Vanden Heuvel. "The Effect of Partial Defoliation on Vine Carbohydrate Concentration and Flavonoid Production in Cranberries." HortScience 41, no. 3 (June 2006): 607–11. http://dx.doi.org/10.21273/hortsci.41.3.607.
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The effect of partial defoliation (rate and timing) on vine carbohydrate concentration and the development of phenolic compounds in field-grown `Stevens' cranberry fruit was investigated in two experiments. In Expt. 1, partial defoliation rates of 0%, 18%, 39%, and 53% of total leaf area were applied before new growth, at fruit set, at midfruit development, and preharvest. In Expt. 2, treatments of 0% and 34% removal of new leaves were applied at postfruit set, and at midfruit development. In both experiments, upright samples were harvested for carbohydrate analysis 10d after defoliation, and fruit were removed for analysis before commercial harvest of the site. While total berry phenolic concentration was unaffected by partial defoliation in both studies, the separate pools of flavonoid compounds were affected differently by treatment. In Expt. 1, total flavonol concentration at harvest was improved by the highest rate of partial defoliation (53% of total leaf area) at both fruit set and midfruit development. Total anthocyanin concentration was improved by partial defoliation rates of 39% and 53% of total leaf area compared to the 18% defoliation treatment, but was not affected by timing of defoliation. Pearson correlation coefficients indicated that total flavonol concentration was positively correlated with vine total nonstructural carbohydrate concentration at preharvest, while total anthocyanin concentration was negatively correlated with vine soluble carbohydrates, starch, and total nonstructural carbohydrate concentration at midfruit development. In Expt. 2, total phenolics, flavonols, and anthocyanins were unaffected by partial defoliation; however there was a negative correlation between total anthocyanin concentration in the fruit and soluble carbohydrate concentration in the vine at midfruit development. In these experiments, partial defoliation early in the growing season improved total flavonols and total anthocyanins. Production of flavonols and anthocyanins appeared to be regulated independently of each other.
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Tang, Diana, Yvonne Tran, Giriraj S. Shekhawat, and Bamini Gopinath. "Dietary Flavonoid Intake and Chronic Sensory Conditions: A Scoping Review." Antioxidants 11, no. 7 (June 21, 2022): 1214. http://dx.doi.org/10.3390/antiox11071214.
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Dietary flavonoids have antioxidant, anti-inflammatory, and vascular health benefits, which align with the proposed pathophysiology of age-related eye conditions and hearing problems (hearing loss and tinnitus). This scoping review is based on Arksey and O’Malley’s six-stage framework and aims to summarise current evidence on the association between the dietary flavonoid intake and chronic sensory conditions in adults, and to identify the research gaps in this area. Eligible studies were identified by searching MEDLINE, EMBASE PsycINFO via the OVID platform, and Google Scholar, as well as manually searching the reference lists of the eligible articles. The inclusion criteria included: articles with full-text access, written in the English language, and focused on chronic sensory conditions and dietary flavonoid intake in an adult population. Studies focused on flavonoid supplements were excluded. Ten studies were included in this review. The evidence suggests that the flavonoid subclass, flavonols, are protective against eye conditions, including age-related macular degeneration, cataract, and glaucoma. There is insufficient evidence to support an association with hearing loss or tinnitus. Overall, dietary flavonol intake appears to be protective against some chronic eye conditions. However, for most eye and hearing-related conditions, only one study was identified. Thus, there is a need for more recent high-quality research to be conducted to confirm any significant associations.
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Zhang, Ying, Yuanyuan Li, Xiaomei Chen, Zhixia Meng, and Shunxing Guo. "Combined Metabolome and Transcriptome Analyses Reveal the Effects of Mycorrhizal Fungus Ceratobasidium sp. AR2 on the Flavonoid Accumulation in Anoectochilus roxburghii during Different Growth Stages." International Journal of Molecular Sciences 21, no. 2 (January 15, 2020): 564. http://dx.doi.org/10.3390/ijms21020564.
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Anoectochilus roxburghii is a traditional Chinese herb with high medicinal value, with main bioactive constituents which are flavonoids. It commonly associates with mycorrhizal fungi for its growth and development. Moreover, mycorrhizal fungi can induce changes in the internal metabolism of host plants. However, its role in the flavonoid accumulation in A. roxburghii at different growth stages is not well studied. In this study, combined metabolome and transcriptome analyses were performed to investigate the metabolic and transcriptional profiling in mycorrhizal A. roxburghii (M) and non-mycorrhizal A. roxburghii (NM) growth for six months. An association analysis revealed that flavonoid biosynthetic pathway presented significant differences between the M and NM. Additionally, the structural genes related to flavonoid synthesis and different flavonoid metabolites in both groups over a period of six months were validated using quantitative real-time polymerase chain reaction (qRT-PCR) and high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). The results showed that Ceratobasidium sp. AR2 could increase the accumulation of five flavonol-glycosides (i.e., narcissin, rutin, isorhamnetin-3-O-beta-d-glucoside, quercetin-7-O-glucoside, and kaempferol-3-O-glucoside), two flavonols (i.e., quercetin and isorhamnetin), and two flavones (i.e., nobiletin and tangeretin) to some degrees. The qRT-PCR showed that the flavonoid biosynthetic genes (PAL, 4CL, CHS, GT, and RT) were significantly differentially expressed between the M and NM. Overall, our findings indicate that AR2 induces flavonoid metabolism in A. roxburghii during different growth stages, especially in the third month. This shows great potential of Ceratobasidium sp. AR2 for the quality improvement of A. roxburghii.
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Yu, Sang Gong, Douglas A. Gage, Nianbai Fang, and Tom J. Mabry. "Flavonols and Flavonol Glycosides from Eupatorium areolare var. leiocarpum." Journal of Natural Products 49, no. 1 (January 1986): 181–82. http://dx.doi.org/10.1021/np50043a039.
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Anwar, Muhammad, Weijun Yu, Hong Yao, Ping Zhou, Andrew C. Allan, and Lihui Zeng. "NtMYB3, an R2R3-MYB from Narcissus, Regulates Flavonoid Biosynthesis." International Journal of Molecular Sciences 20, no. 21 (November 1, 2019): 5456. http://dx.doi.org/10.3390/ijms20215456.
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R2R3-MYB transcription factors play important roles in the regulation of plant flavonoid metabolites. In the current study, NtMYB3, a novel R2R3-MYB transcriptional factor isolated from Chinese narcissus (Narcissus tazetta L. var. chinensis), was functionally characterized. Phylogenetic analysis indicated that NtMYB3 belongs to the AtMYB4-like clade, which includes repressor MYBs involved in the regulation of flavonoid biosynthesis. Transient assays showed that NtMYB3 significantly reduced red pigmentation induced by the potato anthocyanin activator StMYB-AN1 in agro-infiltrated leaves of tobacco. Over-expression of NtMYB3 decreased the red color of transgenic tobacco flowers, with qRT-PCR analysis showing that NtMYB3 repressed the expression levels of genes involved in anthocyanin and flavonol biosynthesis. However, the proanthocyanin content in flowers of transgenic tobacco increased as compared to wild type. NtMYB3 showed expression in all examined narcissus tissues; the expression level in basal plates of the bulb was highest. A 968 bp promoter fragment of narcissus FLS (NtFLS) was cloned, and transient expression and dual luciferase assays showed NtMYB3 repressed the promoter activity. These results reveal that NtMYB3 is involved in the regulation of flavonoid biosynthesis in narcissus by repressing the biosynthesis of flavonols, and this leads to proanthocyanin accumulation in the basal plate of narcissus.
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Wang, Xin, Jianguo Cao, Lin Tian, Baodong Liu, Yawen Fan, and Quanxi Wang. "Elucidating Flavonoid and Antioxidant Activity in Edible and Medicinal Herbs Woodwardia japonica (L.f.) Sm. Based on HPLC-ESI-TOF-MS and Artificial Neural Network Model: Response to Climatic Factors." Molecules 28, no. 4 (February 20, 2023): 1985. http://dx.doi.org/10.3390/molecules28041985.
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Woodwardia japonica is a kind of great potential edible and medicinal fern. In a previous study, it was found that flavonoid and antioxidant activity of W. japonica from different sites were different. However, the cause of the differences has still been unclear, which has restricted the utilization of W. japonica. In this paper, flavonoid and antioxidant activity of W. japonica from nine different regions were determined with the method of a colorimetric assay with UV-VIS spectrophotometry and HPLC-ESI-TOF-MS, and the effects of climate factors on flavonoids and antioxidant activities were evaluated by mathematical modeling and statistical methods. The results showed: (1) total flavonoid content (TFC) of W. japonica from Wuyi Mountain (Jiangxi) was the highest, which might be related to the low temperature; (2) the differences of antioxidant activities of W. japonica might be related to precipitation; (3) five flavonols, two flavones and one isoflavone were tentatively identified in W. japonica; (4) flavonol and isoflavone might be affected by sunshine duration, and flavones were probably related to temperature. In conclusion, the effects of climate factors on flavonoids and antioxidants are significant, which would provide an important basis for further exploring the mechanism of climate affecting secondary metabolites.
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Popiolek-Kalisz, Joanna. "The Impact of Dietary Flavonols on Central Obesity Parameters in Polish Adults." Nutrients 14, no. 23 (November 27, 2022): 5051. http://dx.doi.org/10.3390/nu14235051.
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Background: Central obesity is defined as the excessive fat tissue located in abdominal region accompanied by systemic inflammation, which drives to cardiovascular disease. Flavonols are antioxidative agents present in food. The aim of this study was investigating the relationship between dietary flavonols intake and central obesity. Methods and results: 80 participants (40 central obese and 40 healthy controls) were administered a food frequency questionnaire dedicated to flavonols intake assessment. Body composition was measured with bioelectrical impedance analysis. The analysis showed significant differences between central obese participants and healthy controls in total flavonol (p = 0.005), quercetin (p = 0.003), kaempferol (p = 0.04) and isorhamnetin (p < 0.001) habitual intake. Among central obese participants, there was a moderate inverse correlation between fat mass (FM) and total flavonol (R = −0.378; 95% CI: −0.620 to −0.071; p = 0.02), quercetin (R = −0.352; 95% CI: −0.601 to −0.041; p = 0.03), kaempferol (R = −0.425; 95% CI: −0.653 to −0.127; p = 0.01) and myricetin intake (R = −0.352; 95% CI: −0.601 to −0.041; p = 0.03). BMI was inversely correlated with total flavonol (R = −0.330; 95% CI: −0.584 to −0.016; p = 0.04) and quercetin intake (R = −0.336; 95% CI: −0.589 to −0.023; p = 0.04). Waist circumference was inversely correlated with total flavonol (R = −0.328; 95% CI: −0.586 to −0.009; p = 0.04), quercetin (R = −0.322; 95% CI: −0.582 to −0.002; p = 0.048) and myricetin intake (R = −0.367; 95% CI: −0.615 to −0.054; p = 0.02). Among flavonols’ dietary sources, there was an inverse correlation between black tea consumption and FM (R: −0.511; 95% CI: −0.712 to −0.233; p < 0.001) and between coffee and waist circumference (R: −0.352; 95% CI: −0.604 to −0.036; p = 0.03) in central obese participants. Conclusions: The higher flavonol intake could play a protective role in abdominal obesity development. What is more, total and selected flavonol dietary intakes are inversely correlated with the parameters used for obesity assessment in central obese participants. The habitual consumption of products rich in flavonols, mainly tea and coffee, could possibly have a preventive role in abdominal obesity development.
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Lin, Hsin-Hsien, and Cheng-Yang Huang. "Characterization of Flavonol Inhibition of DnaB Helicase: Real-Time Monitoring, Structural Modeling, and Proposed Mechanism." Journal of Biomedicine and Biotechnology 2012 (2012): 1–11. http://dx.doi.org/10.1155/2012/735368.
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DnaB helicases are motor proteins essential for DNA replication, repair, and recombination and may be a promising target for developing new drugs for antibiotic-resistant bacteria. Previously, we established that flavonols significantly decreased the binding ability ofKlebsiella pneumoniaeDnaB helicase (KpDnaB) to dNTP. Here, we further investigated the effect of flavonols on the inhibition of the ssDNA binding, ATPase activity, and dsDNA-unwinding activity ofKpDnaB. The ssDNA-stimulated ATPase activity ofKpDnaB was decreased to 59%, 75%, 65%, and 57%, in the presence of myricetin, quercetin, kaempferol, and galangin, respectively. The ssDNA-binding activity ofKpDnaB was only slightly decreased by flavonols. We used a continuous fluorescence assay, based on fluorescence resonance energy transfer (FRET), for real-time monitoring ofKpDnaB helicase activity in the absence and presence of flavonols. Using this assay, the flavonol-mediated inhibition of the dsDNA-unwinding activity ofKpDnaB was observed. Modeled structures of bound and unbound DNA showed flavonols binding toKpDnaB with distinct poses. In addition, these structural models indicated that L214 is a key residue in binding any flavonol. On the basis of these results, we proposed mechanisms for flavonol inhibition of DNA helicase. The resulting information may be useful in designing compounds that targetK. pneumoniaeand other bacterial DnaB helicases.
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Forkmann, G., P. de Vlaming, R. Spribille, H. Wiering, and A. W. Schram. "Genetic and Biochemical Studies on the Conversion of Dihydroflavonols to Flavonols in Flowers of Petunia hybrida." Zeitschrift für Naturforschung C 41, no. 1-2 (February 1, 1986): 179–86. http://dx.doi.org/10.1515/znc-1986-1-227.
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Abstract Soluble enzyme preparations from flower buds of Petunia hybrida catalyzed the conversion of dihydroflavonols to flavonols. Dihydrokaempferol and dihydroquercetin were readily converted to the respective flavonols, whereas dihydromyricetin was a poor substrate. The reaction required 2-oxoglutarate, ascorbate and Fe2+ as cofactors and had a pH optimum at about 6.5. In the presence of the dominant allele Fl, high enzyme activity for flavonol formation was found, whereas in enzyme preparations from flower buds of recessive genotypes (fl/fl) only low enzyme activity could be observed. A substantial correlation was found between enzyme activity for flavonol formation and the flavonol content of buds and flowers during development.
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Wang, Yifei, Stephanie K. Fong, Ajay P. Singh, Nicholi Vorsa, and Jennifer Johnson-Cicalese. "Variation of Anthocyanins, Proanthocyanidins, Flavonols, and Organic Acids in Cultivated and Wild Diploid Blueberry Species." HortScience 54, no. 3 (March 2019): 576–85. http://dx.doi.org/10.21273/hortsci13491-18.
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The flavonoid and organic acid profiles of one cultivated tetraploid and six wild diploid blueberry species (Vaccinium spp.) were systematically investigated using high-performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC-ESI-MS-MS). Eighteen individual anthocyanins from five aglycone classes were characterized among species, with malvidin and delphinidin glycosides accounting for 31.4% and 29.1% of total anthocyanins. Twenty-three flavonol glycosides from six aglycone classes were identified, among which quercetin and myricetin glycosides accounted for more than 80% of total flavonols in most species. Both inter- and intraspecies differences in anthocyanin and flavonol composition were observed, as described by principal component analysis. Only B-type proanthocyanidins were found in blueberry species, and highly polymerized molecules with degree of polymerization greater than 10 appeared to be the most abundant fraction. Although overall proanthocyanidin levels varied from 27.7 to 146.3 mg/100 g fruit, all species exhibited similar proanthocyanidin composition. Citric, quinic, and shikimic acid were the major identified blueberry organic acids. However, their relative abundance varied across species. In certain species either citric acid (e.g., Vaccinium darrowii) or quinic acid (e.g., Vaccinium corymbosum) was lacking.
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Rapantová, Barbora, Karel Klem, Petr Holub, Kateřina Novotná, and Otmar Urban. "Photosynthetic response of mountain grassland species to drought stress is affected by UV-induced accumulation of epidermal flavonols." Beskydy 9, no. 1-2 (2016): 31–40. http://dx.doi.org/10.11118/beskyd201609010031.
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Interactive effects of drought and ultraviolet (UV) radiation on CO2 assimilation rate and accumulation of epidermal flavonols were studied in two herbs (Hypericum maculatum and Rumex obtusifolius) and two grasses (Agrostis capillaris and Holcus mollis) under field conditions of Beskydy Mts. The main objective of this study was to evaluate a protective role of epidermal flavonols against drought stress. Experimental shelters were used to manipulate amount of incident precipitation and UV radiation intensity for 12 weeks (May–July). The light-saturated CO2 assimilation rate (Amax) and the content of epidermal flavonols were regularly measured at intervals of 2–3 weeks during the entire period. Drought-induced reduction of Amax was enhanced by high UV intensity in R. obtusifolius, whereas in other species UV radiation reduced a negative effect of drought. Generally, drought increased flavonol content in leaves as compared to non-stressed plants. Similarly, high UV intensities increased the flavonol content in control plants, but not in drought-stressed ones. Regression analysis between the flavonol content and Amax revealed a positive correlation especially for A. capillaris and R. obtusifolius. In both species, a separation of these relationships was observed as the result of water availability. Thus lower Amax were observed at the same flavonol content in drought-stressed plants when compared to control, well-watered counterparts. We conclude that UV-induced accumulation of epidermal flavonols can alleviate negative impacts of summer drought on photosynthesis, particularly in species with slower ontogeny like H. maculatum and A. capillaris.
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Hamamouch, Noureddine, Brenda S. J. Winkel, Chunying Li, and Eric L. Davis. "Modulation of Arabidopsis Flavonol Biosynthesis Genes by Cyst and Root-Knot Nematodes." Plants 9, no. 2 (February 17, 2020): 253. http://dx.doi.org/10.3390/plants9020253.
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Although it is well established that flavonoid synthesis is induced in diverse plant species during nematode parasitism, little is known about the regulation of genes controlling flavonol biosynthesis during the plant–nematode interaction. In this study, expression of the Arabidopsis thaliana flavonol-specific transcription factor, AtMYB12, the flavonol synthase genes, AtFLS1, 2, 3, 4, and 5, and the gene encoding the central flavonoid enzyme, chalcone synthase (AtCHS), were examined in plant roots during infection by Heterodera schachtii (sugar beet cyst) and Meloidogyne incognita (root-knot) nematodes. These experiments showed that AtMYB12 was transiently upregulated at 9 dpi in syncytia associated with sugar beet cyst nematode infection and that an Atmyb12-deficient line was less susceptible to the parasite. This suggests that, rather than contributing to plant defense, this gene is essential for productive infection. However, the AtCHS and AtFLS1 genes, which are controlled by AtMYB12, did not exhibit a similar transient increase, but rather were expressly downregulated in syncytia relative to adjacent uninfected root tissue. Genetic analyses further indicated that AtFLS1 contributes to plant defense against Cyst nematode infection, while other AtFLS gene family members do not, consistent with prior reports that these other genes encode little or no enzyme activity. Together, these findings indicate a role of AtMyb12 in promoting the early stages of Cyst nematode infection, while flavonols produced through the action of AtFLS1 are essential for plant defense. On the other hand, a transient induction of AtMYB12 was not observed in galls produced during root-knot nematode infection, but this gene was instead substantially downregulated, starting at the 9 dpi sampling point, as were AtCHS and AtFLS1. In addition, both the AtMYB12- and AtFLS1-deficient lines were more susceptible to infection by this parasite. There was again little evidence for contributions from the other AtFLS gene family members, although an AtFLS5-deficient line appeared to be somewhat more susceptible to infection. Taken together, this study shows that sugar-beet cyst and root-knot nematodes modulate differently the genes involved in flavonol biosynthesis in order to successfully infect host roots and that AtFLS1 may be involved in the plant basal defense response against nematode infection.
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Zheng, Li. "Dihydro Flavonols Maybe an Effective and Specific Novel Treatment for Alcoholism by Affecting the Express of Aminobutyric Acid." Advanced Materials Research 881-883 (January 2014): 356–59. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.356.
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Flavonols is a class of widely distributed in nature polyphenols. Usually, studies have shown that lots of flavonols had certain effect on alcoholism. Studies have show that lots of flavonoids have effect on aminobutyric acid (GABA) which is an important inhibitory neurotransmitter mammalian in central nervous system. Dihydro flavonols, an kind of flavonols may have effect on alcoholism by GABA. Recent studies have shown that dihydro myricetin, an dihydro flavonol, has shown inhibition of GABA receptor gene expression. In like manner, we hypothesize that dihydro flavonols may affect the express of GABA as an effective and specific novel treatment for alcoholism.
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Cai, Shi-Qing, Qiang Zhang, Xin-Huai Zhao, and Jia Shi. "The In Vitro Anti-Inflammatory Activities of Galangin and Quercetin towards the LPS-Injured Rat Intestinal Epithelial (IEC-6) Cells as Affected by Heat Treatment." Molecules 26, no. 24 (December 10, 2021): 7495. http://dx.doi.org/10.3390/molecules26247495.
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Flavonols possess several beneficial bioactivities in vitro and in vivo. In this study, two flavonols galangin and quercetin with or without heat treatment (100 °C for 15–30 min) were assessed for their anti-inflammatory activities in lipopolysaccharide (LPS)-stimulated rat intestinal epithelial (IEC-6) cells and whether the heat treatment caused activity changes. The flavonol dosages of 2.5–20 μmol/L had no cytotoxicity on the cells but could enhance cell viability (especially using 5 μmol/L flavonol dosage). The flavonols could decrease the production of prostaglandin E2 and three pro-inflammatory cytokines interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α, and simultaneously promote the production of two anti-inflammatory cytokines IL-10 and transforming growth factor-β. The Western-blot results verified that the flavonols could suppress the LPS-induced expression of TLR4 and phosphorylated IκBα and p65, while the molecular docking results also illustrated that the flavonols could bind with TLR4 and NF-κB to yield energy decreases of −(21.9–28.6) kJ/mol. Furthermore, an inhibitor BAY 11-7082 blocked the NF-κB signaling pathway by inhibiting the expression of phosphorylated IκBα/p65 and thus mediated the production of IL-6/IL-10 as the flavonols did, which confirmed the assessed anti-inflammatory effect of the flavonols. Consistently, galangin had higher anti-inflammatory activity than quercetin, while the heated flavonols (especially those with longer heat time) were less active than the unheated counterparts to exert these target anti-inflammatory effects. It is highlighted that the flavonols could antagonize the LPS-caused IEC-6 cells inflammation via suppressing TLR4/NF-κB activation, but heat treatment of the flavonols led to reduced anti-inflammatory efficacy.
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Rha, Chan-Su, Hyunbin Seong, Young Sung Jung, Davin Jang, Jun-Gu Kwak, Dae-Ok Kim, and Nam Soo Han. "Stability and Fermentability of Green Tea Flavonols in In-Vitro-Simulated Gastrointestinal Digestion and Human Fecal Fermentation." International Journal of Molecular Sciences 20, no. 23 (November 24, 2019): 5890. http://dx.doi.org/10.3390/ijms20235890.
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Flavonols, the second most abundant flavonoids in green tea, exist mainly in the form of glycosides. Flavonols are known to have a variety of beneficial health effects; however, limited information is available on their fate in the digestive system. We investigated the digestive stability of flavonol aglycones and glycosides from green tea under simulated digestion and anaerobic human fecal fermentation. Green tea fractions rich in flavonol glycosides and aglycones, termed flavonol-glycoside-rich fraction (FLG) and flavonol-aglycone-rich fraction (FLA) hereafter, were obtained after treatment with cellulase and tannase, respectively. Kaempferol and its glycosides were found to be more stable in simulated gastric and intestinal fluids than the derivatives of quercetin and myricetin. Anaerobic human fecal fermentation with FLG and FLA increased the populations of Lactobacilli spp. and Bifidobacteria spp. and generated various organic acids, such as acetate, butyrate, propionate, and lactate, among which butyrate was produced in the highest amount. Our findings indicate that some stable polyphenols have higher bioaccessibilities in the gastrointestinal tract and that their health-modulating effects result from their interactions with microbes in the gut.