Academic literature on the topic 'Guaijaverin'

In the course of our studies on antidiabetogenic and antidiabetic principles of natural medicines and medicinal foodstuffs, we have isolated salacinol and kotalanol with unique thiosugar sulfonium sulfate inner salt structures from the antidiabetic Ayurvedic traditional medicines, Salacia reticulata and S. oblonga. Salacinol and kotalanol showed potent inhibitory activities against intestinal α-glucosidase, and also inhibitory effects of salacinol on the increase in serum glucose levels in maltose- and sucrose-loaded rats were found to be more potent than those of acarbose. In addition, various flavonoids with potent inhibitory activities against rat lens aldose reductase such as quercitrin desmanthin-1 and guaijaverin were isolated from Myrcia multiflora and several natural medicines, and some structural requirements of flavonoids for aldose reductase inhibitory activity were clarified.

Psidium guajava (L.) belongs to the Myrtaceae family and it is an important fruit in tropical areas like India, Indonesia, Pakistan, Bangladesh, and South America. The leaves of the guava plant have been studied for their health benefits which are attributed to their plethora of phytochemicals, such as quercetin, avicularin, apigenin, guaijaverin, kaempferol, hyperin, myricetin, gallic acid, catechin, epicatechin, chlorogenic acid, epigallocatechin gallate, and caffeic acid. Extracts from guava leaves (GLs) have been studied for their biological activities, including anticancer, antidiabetic, antioxidant, antidiarrheal, antimicrobial, lipid-lowering, and hepatoprotection activities. In the present review, we comprehensively present the nutritional profile and phytochemical profile of GLs. Further, various bioactivities of the GL extracts are also discussed critically. Considering the phytochemical profile and beneficial effects of GLs, they can potentially be used as an ingredient in the development of functional foods and pharmaceuticals. More detailed clinical trials need to be conducted to establish the efficacy of the GL extracts.

Three new acylated flavonol diglycosides that were characterized as quercetin 3- O-(6′”- O-E-isoferuloyl)-sophoroside (1), quercetin 3- O-(6′”- O-Z-isoferuloyl)-sophoroside (2) and quercetin 3- O-[2″- O-( E-6″′- O-isoferuloyl)-β-D-glucopyranosyl]-β-D-galactopyranoside (3), along with twelve known metabolites, have been isolated from the leaves of Cynanchum acutum L. The latter were identified as quercetin 3- O-β-D-neohesperidoside (4), rutin (5), quercetin 3- O-sophoroside (6), kaempferol 3- O-β-D-rutinoside (7), quercitrin (8), isoquercitrin (9), hyperin (10), guaijaverin (11), quercetin 7- O-β-D-glucopyranoside (12), quercetin (13), scopoletin (14) and ( E)-3-(3,4-dihydroxyphenyl)-propenoic acid (15). All metabolites have been isolated for the first time from the genus Cynanchum, except for 9 and 14. The structures were determined on the basis of chromatographic behavior, acid hydrolysis, chemical and physicochemical evidence (UV, HRESI-MS/MSn, 1H, 13C NMR, 1H-1H COSY, HSQC and HMBC). The chloroform extract and compounds 8 and 10 exhibited lethal effects towards brine shrimp, Artemia salina.

Schisandra rubriflora is a dioecious, underestimated medicinal plant species known from traditional Chinese medicine. The present study was aimed at characterising the polyphenolic profile composition and the related antioxidant capacity of S. rubriflora fruit, stem and leaf and in vitro microshoot culture extracts. Separate analyses of material from female and male specimens were carried out. This study was specifically aimed at detailed characterisation of the contribution of phenolic compounds to overall antioxidant activity using ultra-high-performance liquid chromatography with a photodiode array detector coupled to electrospray ionization ion trap mass spectrometry (UHPLC-DAD-ESI-MS3) and a high-performance liquid chromatography-diode array detector (HPLC-DAD). Using UHPLC-DAD-ESI-MS3, twenty-seven phenolic compounds from among phenolic acids and flavonoids were identified. Concentrations of three phenolic acids (neochlorogenic, chlorogenic and cryptochlorogenic acids) and eight flavonoids (hyperoside, rutoside, isoquercitrin, guaijaverin, trifolin, quercetin, kaempferol, and isorhamnetin) were determined using HPLC-DAD using reference standards. The highest total phenolic content was confirmed for the stem and leaf extracts collected in spring. The contents of phenolic compounds of in vitro biomasses were comparable to that in the fruit extracts. The methanolic extracts from the studied plant materials were evaluated for their antioxidant properties using various in vitro assays, namely free radicals scavenging estimation using 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), ferric-reducing antioxidant power (FRAP) and cupric-reducing antioxidant capacity (CUPRAC) as well as QUick, Easy, New, CHEap, and Reproducible CUPRAC (QUENCHER-CUPRAC) assays. A close relationship between the content of polyphenolic compounds in S. rubriflora and their antioxidant potential has been documented.

Plantas da família Guttiferae apresentam diversas atividades biológicas sendo Hypericum o gênero mais importante devido às atividades antidepressiva, antibacteriana e antiviral de algumas espécies. Hypericum connatum, utilizado no sul do Brasil para o tratamento de feridas de boca, demonstrou atividade contra o lentivírus, responsável pela imunodeficiência felina. Objetivo: isolar e identificar as substâncias majoritárias de H. connatum e testar a atividade de extratos obtidos das partes aéreas e raízes e das substâncias isoladas frente a duas cepas do herpesvírus simples tipo 1 (HSV-1). Método: foram obtidos frações nhexano, diclorometano e metanol e extratos bruto, aquosos a diferentes temperaturas e hidro-etanólico das partes aéreas e raízes. As frações n-hexano e metanólica das partes aéreas foram submetidas à coluna cromatográfica para o isolamento de substâncias. Os extratos e substâncias isoladas foram testados frente ao HSV-1, cepas KOS e ATCC-VR733. Determinou-se a concentração máxima não tóxica (CMNT) à célula e a concentração que provoca alteração morfológica em 50% das células (CC50) pela técnica da alteração morfológica celular, utilizando-se células VERO, linhagem ATCC CCL-81. A avaliação da atividade antiviral foi realizada em placas de microtitulação e medida pela inibição do efeito citopático (ECP) provocado pelo vírus. Resultados e Conclusões: da fração n-hexano foi isolado hiperbrasilol B, da fração metanólica foram isolados amentoflavona, hiperosídeo e guaijaveriana, além de um flavonol de estrutura ainda não definida (HCN3). A fração n-hexano e o extrato bruto das raízes inibiram o ECP das cepas KOS e ATCC-VR733. Os demais extratos testados não apresentaram atividade antiviral. Dentre as substâncias analisadas, hiperbrasilol B, amentoflavona e HCN3 foram ativos frente às duas cepas. Os flavonóides hiperosídeo e guaijaverina não apresentaram atividade anti-HSV-1.<br>Plants from Guttiferae family present many biological activities being Hypericum the most important genus due to the antidepressive, antiinflamatory and antimicrobial activities of some species. Hypericum connatum, used in south of Brazil for the treatment of mouth wounds, demonstrated activity against the feline immunodeficiency virus. Purpose: to isolate and identify the major compounds from H. connatum and to test extracts and compounds obtained from the roots and aerial parts against two strains of the herpes simplex virus type 1. Method: nhexane, dichloromethane and methanol fractions and aqueous and hydroethanolic from the aerial parts and roots were obtained. The n-hexane and methanolic fractions from the aerial parts were submitted to column chromatography. All extracts and isolated compounds were tested against the herpes simplex virus type 1, strains KOS and ATCC-VR733. The determination of The maximum non-toxic concentrations (CMNT) and the concentration that causes morphologic alterations in 50% of the cells (CC50) was carried out by the technique of cellular morphologic alterations, using VERO cells, strain ATCC CCL-81. The assay was performed in 96-well plates and the antiviral activity was evaluated by the inibition of the measured by the viral cytopathogenic effect assay (ECP). Results and Conclusions: hyperbrasilol B was isolated from the n-hexane fraction; amentoflavone, hyperoside, guaijaverin, and a flavonol not yet identified (HCN3) were isolated from methanolic fraction. The n-hexane fraction and the crude methanolic extracts were active against both strains tested. The other extracts tested did not display antiviral activity. Among the isolated compounds, hyperbrasilol B, amentoflavone and HCN3 were active against both strains. Hyperoside and guaijaverin were not active against HSV-1.