Academic literature on the topic 'Hibiscus sabdariffa'
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Journal articles on the topic "Hibiscus sabdariffa"
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Kwofie, J., H. M. Amoatey, W. Nunekpeku, J. K. Ahiakpa, and C. Katsepor. "Crossability Studies among Twenty Accessions of Roselle (Hibiscus sabdariffa L.)." Journal of Agricultural Science 9, no. 9 (August 15, 2017): 230. http://dx.doi.org/10.5539/jas.v9n9p230.
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Increasing exploitation of roselle (Hibiscus sabdariffa L.) and its products require that commercial varieties with superior attributes are developed to replace landrace varieties and to meet the growing demand for commercial-scale cultivation of the crop. In this study, twenty landrace varieties of roselle collected from three geographical regions of Ghana were artificially crossed in a pairwise mating scheme. The aim was to obtain relevant information pertaining to fertility status and extent of crossability among the accessions to facilitate breeding of improved varieties. Attempts at hybridisation were made both between and among 6 accessions of Hibiscus sabdariffa var Altissima and 14 accessions of Hibiscus sabdariffa var Sabdariffa. Crosses between accessions of Hibiscus sabdariffa var Altissima and Hibiscus sabdariffa var Sabdariffa yielded no hybrids, suggestive of a crossability barrier between the two mating groups. All intra-varietal crosses involving accessions of Hibiscus sabdariffa var Altissima were successful regardless of direction of cross while only few of the crosses among those of Hibiscus sabdariffa var Sabdariffa produced successful hybrids. Also fertility estimates of members of Hibiscus sabdariffa var Altissima were significantly higher (30.00%-80.00%) compared to those of var Sabdariffa (0.00%-43.00%). This implies that complete pairwise design could be used for intra-varietal crosses involving accessions of Hibiscus sabdariffa var Altissima, whereas only a partial pairwise design is feasible for members of Hibiscus sabdariffa var Sabdariffa.
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Barros de Nogueira, Ruama Viana, Virginia Freitas Rodrigues, Sílvia Menezes de Faria Pereira, and Inêz Barcellos de Andrade. "FLORES DE HIBISCO (Hibiscus sabdariffa) COMERCIALIZADAS NO MUNICÍPIO DE CAMPOS DOS GOYTACAZES-RJ: UMA ANÁLISE DO PERFIL FITOQUÍMICO E DO USO POPULAR, CONSIDERANDO ATIVIDADES ATRIBUIDAS ÀS RESPECTIVAS CLASSES DE METABÓLIDOS SECUNDÁRIOS ENCONTRADAS." Revista Científica da Faculdade de Medicina de Campos 16, no. 1 (April 30, 2021): 12–18. http://dx.doi.org/10.29184/1980-7813.rcfmc.253.vol.16.n1.2021.
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As formas mais antigas para prevenção de doenças, tratamento e cura, estão na utilização das plantas medicinais. Dentre as várias espécies utilizadas pela população, encontra-se o Hibisco (Hibiscus sabdariffa). Pertencente à família botânica Malvaceae, o Hibisco é um arbusto anual, nativo dos continentes africano e asiático, que se encontra distribuído nas regiões tropicais e subtropicais de ambos os hemisférios, tornando-se naturalizado em muitas áreas das Américas. Estudos têm comprovado o uso de Hibisco como agente diurético, antimicrobiano, laxante, sedativo, anti-hipertensivo, entre outros. Mais recentemente, há indicativo de que o Hibisco possa agir como antioxidante, antimutagênico, antitumoral e antileucêmico. O presente trabalho teve como objetivo realizar uma análise fitoquímica preliminar nas flores de Hibiscus sabdariffa, comercializadas em Campos dos Goytacazes, RJ, e correlacionar os resultados obtidos com as atividades farmacológicas atribuídas às classes de metabólitos encontrados. O presente estudo revelou a presença de grande quantidade (52,09%) de metabólitos de alta polaridade nas flores de Hibisco. Análise fitoquímica de identificação revelou a presença do metabólito secundário da classe dos taninos, nas flores analisadas da espécie vegetal (Hibiscus sabdariffa). A análise de identificação de flavonoides, por sua vez, não permitiu confirmar a presença desse metabólito visto que a coloração da própria espécie mascarou o resultado. As atividades atribuídas, em referências bibliográficas, à espécie Hibiscus sabdariffa, em especial antimicrobiana e antibiótica, foi compatível com as atividades relacionadas à classe de metabólitos identificada na amostra. Tal estudo revela um resultado preliminar, mas pode nortear outros estudos na busca de substâncias com atividade antioxidante.
As formas mais antigas para prevenção de doenças, tratamento e cura, estão na utilização das plantas medicinais. Dentre as várias espécies utilizadas pela população, encontra-se o Hibisco (Hibiscus sabdariffa). Pertencente à família botânica Malvaceae, o Hibisco é um arbusto anual, nativo dos continentes africano e asiático, que se encontra distribuído nas regiões tropicais e subtropicais de ambos os hemisférios, tornando-se naturalizado em muitas áreas das Américas. Estudos têm comprovado o uso de Hibisco como agente diurético, antimicrobiano, laxante, sedativo, anti-hipertensivo, entre outros. Mais recentemente, há indicativo de que o Hibisco possa agir como antioxidante, antimutagênico, antitumoral e antileucêmico. O presente trabalho teve como objetivo realizar uma análise fitoquímica preliminar nas flores de Hibiscus sabdariffa, comercializadas em Campos dos Goytacazes, RJ, e correlacionar os resultados obtidos com as atividades farmacológicas atribuídas às classes de metabólitos encontrados. O presente estudo revelou a presença de grande quantidade (52,09%) de metabólitos de alta polaridade nas flores de Hibisco. Análise fitoquímica de identificação revelou a presença do metabólito secundário da classe dos taninos, nas flores analisadas da espécie vegetal (Hibiscus sabdariffa). A análise de identificação de flavonoides, por sua vez, não permitiu confirmar a presença desse metabólito visto que a coloração da própria espécie mascarou o resultado. As atividades atribuídas, em referências bibliográficas, à espécie Hibiscus sabdariffa, em especial antimicrobiana e antibiótica, foi compatível com as atividades relacionadas à classe de metabólitos identificada na amostra. Tal estudo revela um resultado preliminar, mas pode nortear outros estudos na busca de substâncias com atividade antioxidante.
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Karmana, I. Wayan. "Artikel Review : Bioaktivitas Bunga Rosella (Hibiscus sabdariffa L.) Beserta Pemanfaatannya." Educatoria : Jurnal Ilmiah Ilmu Pendidikan 3, no. 3 (July 30, 2023): 208–16. http://dx.doi.org/10.36312/educatoria.v3i3.200.
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Hibiscus sabdariffa is a species of the Malvaceae family which has long been used by humans as a traditional medicine. The use of Hibiscus sabdariffa as a traditional medicine is related to its bioactivity. Hibiscus sabdariffa has several pharmacological potentials, namely: 1) anticancer; 2) antioxidants; 3) antibacterial; 4) antiaging; 5) antiseptic; and 6) antihypertensive. The method of writing this article is a literature review published online, especially on Google Scholar using the keywords Hibiscus sabdariffa, bioactivity and utilization of Hibiscus sabdariffa. The results of this review state that rosella flowers (Hibiscus sabdariffa L.) have potential as anticancer, antioxidants, antihypertensive antibacterials, and low caffeinated tea drinks.
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Yuliastri, W. O., A. Diantini, M. Ghozali, I. Sahidin, and M. Isrul. "PHYTOCHEMICAL CONSTITUENT AND In-vitro CYTOTOXIC ACTIVITY OF Hibiscus sabdariffa L. CALYX FRACTION ON HUMAN BREAST CANCER CELL LINE MDA-MB-231." RASAYAN Journal of Chemistry 15, no. 03 (2022): 1619–25. http://dx.doi.org/10.31788/rjc.2022.1536694.
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Hibiscus sabdariffa L. is a medicinal plant that has various pharmacological activities. One of the activities of Hibiscus sabdariffa L. is the immunomodulatory activity closely connected with the anticancer activities. This study aimed to test the cytotoxic activity of Hibiscus sabdariffa L. Calyx Fractions against breast cancer cells (MDA-MB-231), determine the active fractions, and analyze the compounds of the active fraction of Hibiscus sabdariffa L. with LCMS. The Hibiscus sabdariffa L.Calyx was fractionated using vacuum liquid chromatography. Meanwhile, the cytotoxic activity was examined using the MTT method. The test results discovered that the Fraction A of Hibiscus sabdariffa L. Calyx is the active fraction with a score of IC50 187.89 µg/ml. The identification of Fraction A's chemical compounds using LC-MS discovered three identified compounds:tert-butyl-4-methoxy phenol Nigakilactone H and Stigmastan-3,6-dione. Since these compounds potentially function as active cytotoxic compounds,it is suggested that further studies isolate the active compounds from Fraction A of Hibiscus sabdariffa L.
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Lestari, Gusti Ayu Dewi. "SKRINING FITOKIMIA DAN UJI AKTIVITAS ANTIOKSIDAN EKSTRAK ETANOL BUNGA ROSELLA UNGU (Hibiscus sabdariffa L.)." Jambura Journal of Chemistry 4, no. 1 (March 10, 2022): 17–24. http://dx.doi.org/10.34312/jambchem.v4i1.11157.
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Ekstrak etanol bunga rosella ungu (Hibiscus sabdariffa L.) mengandung senyawa fitokimia potensial sebagai antioksidan. Tujuan penelitian ini adalah untuk mengetahui kandungan senyawa pada bunga rosella ungu (Hibiscus sabdariffa L.) serta potensinya sebagai antioksidan. Bunga rosella ungu (Hibiscus sabdariffa L.) diekstraksi menggunakan metode maserasi dan diperoleh persentase rendemen hasil sebesar 35,25%. Skrining fitokimia dilakukan dengan metode KLT dimana ekstrak etanol bunga rosella ungu (Hibiscus sabdariffa L.) positif mengandung alkaloid, flavonoid, tanin dan saponin. Hasil uji aktivitas antioksidan dengan menggunakan DPPH (2,2-difenil-1-pikrilhidrazil) diperoleh nilai IC50 sebesar 38,2939 ppm dimana ekstrak etanol bunga rosella ungu (Hibiscus sabdariffa L.) memiliki aktivitas antioksidan sangat kuat. Nilai AAI (antioxidant activity index) diperoleh 1,04. Nilai presisi dan linearitas pada metode ini adalah 7,67% dan r2 = 0,9929 sehingga metode ini dapat dikatakan memiliki presisi dan linearitas yang baik. Dari hasil penelitian yang telah dilakukan, maka dapat disimpulkan bahwa bunga rosella ungu (Hibiscus sabdariffa L.) memiliki aktivitas antioksidan yang sangat kuat karena mengandung senyawa flavonoid, alkaloid, tanin dan saponin yang dapat menangkal radikal bebas.
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Kasimo, Elfred, Lisa Savitri, Mujtahid Bin Abd Kadir, Moh Alimansur, and Ester Lianawati Antoro. "TOKSISITAS KOMBINASI EKSTRAK ROSELA (Hibiscus sabdariffa L.) DAN PARE (Momordica charantia) DENGAN METODE BRINE SHRIMP LETHALITY TEST (BSLT)." GEMA KESEHATAN 15, no. 2 (December 28, 2023): 168–76. http://dx.doi.org/10.47539/gk.v15i2.441.
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Rosela (Hibiscus sabdariffa L.) dan pare (Momordica charantia) mengandung senyawa kimia yang bermanfaat bagi kesehatan, seperti asam fenolat, tannin, flavonoid, alkaloid, saponin, tanin, glikosida, dan steroid. Penelitian ini bertujuan untuk mengetahui tingkat toksisitas ekstrak kombinasi bunga rosela (Hibiscus sabdariffa L.) dan buah pare (Momordica charantia) terhadap larva Artemia salina Leach menggunakan metode Brine Shrimp Lethality Test (BSLT). Tingkat toksisitas tersebut ditunjukkan dengan nilai LC50. Metode: Penelitian uji toksisitas kombinasi ekstrak Hibiscus sabdariffa L dan Momordica charantia terhadap larva udang (Artemia salina L.) menggunakan metode BSLT. Dalam penelitian ini, ekstrak kombinasi bunga rosela dan buah pare diuji toksisitasnya terhadap larva Artemia salina Leach dengan konsentrasi 1000 ppm, 500 ppm, 200 ppm, 100 ppm, dan 50 ppm. Pengujian dilakukan sebanyak tiga kali pada masing-masing konsentrasi. Data hasil pengujian dianalisis menggunakan analisa probit, dan log konsentrasinya dihitung untuk mengetahui nilai LC50. Hasil : Ekstrak kombinasi bunga rosela (Hibiscus sabdariffa L.) dan buah pare (Momordica charantia) memiliki nilai LC50 sebesar 241,8 ppm. Kata kunci: BSLT, Hibiscus sabdariffa L, Momordica charantia Roselle (Hibiscus sabdariffa L.) and bitter melon (Momordica charantia) contain chemical compounds that are beneficial for health, such as phenolic acids, tannins, flavonoids, alkaloids, saponins, tannins, glycosides, and steroids. This study aims to determine the level of toxicity of the combined extract of roselle flowers (Hibiscus sabdariffa L.) and bitter melon fruit (Momordica charantia) against Artemia salina Leach larvae using the Brine Shrimp Lethality Test (BSLT) method. The LC50 value indicates the level of toxicity. Process: Research the toxicity test of a combination of Hibiscus sabdariffa L. and Momordica charantia extracts against shrimp larvae (Artemia salina L.) using the BSLT method. This research tested the combined extract of roselle flowers and bitter melon fruit for toxicity against Artemia salina Leach larvae at concentrations of 1000 ppm, 500 ppm, 200 ppm, 100 ppm, and 50 ppm. The test was carried out three times at each concentration. The test result data was analyzed using probit analysis, and the concentration log was calculated to determine the LC50 value. Results: The combination extract of roselle flowers (Hibiscus sabdariffa L.) and bitter melon fruit (Momordica charantia) had an LC50 value of 241.8 ppm. Keywords: BSLT, Hibiscus sabdariffa L, Momordica charantia
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Firmasari, Firmasari, Ni Ketut Sumarni, Ruslan, and Hardi Ys. "PERSEN DEGRADASI EKSTRAK ETANOL KELOPAK BUNGA ROSELLA (Hibiscus sabdariffa L.) SELAMA PENYIMPANAN THE PERCENTAGE OF ETHANOL EXTRACTS OF ROSELLE PETALS (Hibiscus sabdariffa L.) DURING STORAGE." KOVALEN: Jurnal Riset Kimia 5, no. 2 (August 31, 2019): 132–38. http://dx.doi.org/10.22487/kovalen.2019.v5.i2.9970.
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Ethanol extract of roselle petals (Hibiscus sabdariffa L.) is more stable in low pH than in high pH. The research aims to monitor and determine the effect of ratio content in ethanol extract of roselle petals (Hibiscus sabdariffa L.) in tomato sauce and the pH effect on the percentage of ethanol extract degradation during storage. Two independent variables implemented in this study, are ratio content of ethanol extract of roselle petals (Hibiscus sabdariffa L.) in tomato sauce and pH. Ethanol extract of roselle petals (Hibiscus sabdariffa L.) in tomato sauce with ratio content 0,5:1; 1:1; and 1:0 (w/w) and adjusted to pH 2, pH 3, pH 4, pH 5 and pH 6, respectively were investigated. The absorbance measurement of Ethanol extract of roselle petals (Hibiscus sabdariffa L.) in tomato sauce was depend on each treatment, then analyzed using completely randomized design. The percentage of ethanol extract of roselle petals (Hibiscus sabdariffa L.) degradation in tomato sauce decreased in ratio content 1:0 (w/w) at pH 2 with percentage content of degradation is 30.09%. Furthermore, after 10 days of storage, the highest percentage of ethanol extract of roselle petals (Hibiscus sabdariffa L.) in tomato sauce degradation is 93.33% with ratio content is 0.5:1 at pH 6 and the lowest is 30.09% with ratio content 1:0 at pH 2.
Keywords: Roselle petals, Ethanol Extract, Tomato Sauce, Percentage of Degradation
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Choon Yoong Cheok and Anusuyah Ragunathan. "Anthocyanin degradation kinetics and thermodynamic analysis of Hibiscus rosa-sinensis L. Clitoria ternatea L. and Hibiscus sabdariffa L." Progress in Energy and Environment 19, no. 1 (August 23, 2022): 1–12. http://dx.doi.org/10.37934/progee.19.1.112.
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Anthocyanins are natural occurrence red pigments existed in most flowers with high health benefited values. These anthocyanins rich flowers have a short shelf life and fast degradation when in fresh stage. These anthocyanins rich flowers have a short shelf life and fast degradation when in fresh stage. Therefore, drying is a conventional way to preserve them from rotten in order to be reachable for urban consumers who have busy life style and limited space for planting. The present study was conducted to evaluate the anthocyanin degradation kinetics of Hibiscus rosa-sinensis L., Clitoria ternatea L. and Hibiscus sabdariffa L. at drying temperatures of 50, 60, 70 and 80 °C for durations of 10, 20, 30 and 40 min. Anthocyanin degradation kinetic order of Hibiscus rosa-sinensis L., Clitoria ternatea L. and Hibiscus sabdariffa L. were determined by constructing natural logarithm Arrhenius equation plots from k values obtained from zero-, first-, and second-order integrated rate law plots at each temperature levels of 50 °C, 60 °C, 70 °C and 80 °C, based on the highest coefficient of determination (R2). Fresh flower of Clitoria ternatea L. has been revealed possessed the highest amount of TMA followed by Hibiscus sabdariffa L. and the Hibiscus rosa-sinensis L. Results revealed that anthocyanins degradation for Hibiscus rosa-sinensis L. and Clitoria ternatea L. followed first-order kinetic behaviour, while Hibiscus Sabdariffa L. followed the second-order. Anthocyanins of Hibiscus Sabdariffa L. has been discovered having high k values which led to shorter half-life values. However, anthocyanins of Hibiscus Sabdariffa L. is more stable during heat drying treatment as evidenced by higher activation energy and activation enthalpy, but lower free Gibbs energy and absolute value of entropy in comparison to Hibiscus rosa-sinensis L. and Clitoria ternatea L. Therefore, Hibiscus sabdariffa L. is highly recommended to be used as food colorant in food processing industries which involve heating.
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Freitas, Nélio Martins, Angela Maria Correa Mouzinho Santos, and Lucy Rose de Maria Oliveira Moreira. "AVALIAÇÃO FITOQUÍMICA E DETERMINAÇÃO DE MINERAIS EM AMOSTRAS de Hibiscus sabdariffa L (vinagreira)." Cadernos de Pesquisa 20, no. 3 (December 21, 2013): 65. http://dx.doi.org/10.18764/2178-2229.v20n3p65-72.
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O presente trabalho teve como objetivo determinar por espectroscopia de emissão óptica com plasma indutivamente acoplado (ICP OES) o teor dos minerais cobalto, cobre, ferro, fósforo, cálcio, magnésio,manganês, níquel, potássio e zinco, presentes nas folhas e no caule do Hibiscus sabdariffa L (vinagreira).Fez-se a triagem fitoquímica para verificar os compostos fitoquímicos como saponinas, taninos, fenóis, terpenos, esteróides, alcalóides, resinas, e flavonóides) da vinagreira coletada do município de São José de Ribamar-MA, onde os agricultores plantam o H. sabdariffa L) e comercializam para a maioria das feiras dessa região. Para os testes fitoquímicos realizados no caule e nas folhas da planta observaram-se saponinase esteróides moderamente positivo, taninos tanto condensado como hidrolisado fraco positivamente. As resinas foram encontradas moderadamente no caule e ausente na folha do H. sabdariffa L. Para os teste de flavonóides obteve reação forte para o caule e moderada para a folha. Observou-se a ausência de fenóis, terpenos e alcalóides. Em relação ao teor de metais presente no caule e na folha do H. sabdariffa L (vinagreira) verificaram-se respectivamente, uma quantidade significativa de ferro (11,91 e 30,04 mg/l) e cálcio (6,08 e 7,09 mg/l); para os demais minerais, o teor foi menor: magnésio (0,31 mg/l), potássio (0,36 e 0,72 mg/l) manganês (0,14 e 0,02 mg/l) e fósforo somente nas folhas (0,62 mg/l).Palavras-chave: Hibiscus sabdariffa L. Minerais. Espectroscopia. PHYTOCHEMISTRY EVALUATION AND DETERMINATION OF MINERAL SIN SAMPLES Hibiscus Sabdariffa L (vinegar)Abstract: This study aimed to determine by optical emission spectroscopy with inductively coupled plasma (ICP OES), the mineral content of cobalt, copper, iron, phosphorus, calcium, magnesium, manganese, nickel,potassium and zinc, present in the leaves and the stem of Hibiscus sabdariffa L (vinagreira). Became the phytochemical screening to check phytochemicals like saponins, tannins, phenols, terpenes, steroids, alkaloids, resins, and flavonoids) of vinegar collected in São José de Ribamar-MA, where farmers plant H. sabdariffa L ), and trade fairs for most of this region. For the tests performed phytochemicals in stems and leaves of the plant was observed saponins and steroids moderately positive, both condensed tannins hydrolyzateas weak positive. The resins were found moderately in stems and absent in leaf H. sabdariffa L. For the test flavonoids obtained strong reaction to stem and leaf to moderate. We observed the absence of phenols, terpenes and alkaloids. WRegarding the metal content present in the stem and leaf H. sabdariffa L (vinegar) respectively, a significant amount of iron (11,91 and 30,04 mg /l), calcium (6,08 and 7,09 mg/l) for the remaining minerals content was lower: Magnesium (0,31 mg/l), potassium (0,36 and 0,72 mg /l) Mn (0,14 and 0,02 mg/ l) and only on phosphor sheets (0,62 mg/l).Keywords: Hibiscus sabdariffa L. Mmineral. Spectroscopy. EVALUACIÓN FITOQUÍMICA Y DETERMINACIÓN DE MINERALES EN MUESTRA SEN MUESTRAS Hibiscus SabdariffaL (vinagre)Resumen: Este estudio tuvo como objetivo determinar por espectroscopia de emisión óptica con plasma acoplado inductivamente (ICP OES), la concentración de minerales de cobalto, cobre, hierro, fósforo, calcio,magnesio, manganeso, níquel, potasio y zinc, presentes en las hojas y el tallo de Hibiscus sabdariffa L (vinagrera). Se realizaron los ensayos generales para comprobar la presencia de fitoquímicos como saponinas,taninos, fenoles, terpenos, esteroides, alcaloides, resinas y flavonoides) en la vinagrera recogida en São José de Ribamar-MA, donde los agricultores siembran H. sabdariffa L, y la comercializan en las ferias de la mayor parte de esta región. En las pruebas realizadas para la detección de fitoquímicos en los tallos y hojas de la planta se observó saponinas y esteroides moderadamente positivos, taninos tanto condensados como hidrolizados dando positivo débil. Las resinas se encuentran moderadamente en los tallos y ausentes en las hojas de H. sabdariffa L. En los ensayos para flavonoides se obtuvo fuerte reacción en los tallos y moderada en las hojas. Se observó la ausencia de fenoles, terpenos y alcaloides. En cuanto al contenido de metales presentes en el tallo y en las hojas de H. sabdariffa L (vinagrera), respectivamente había una cantidad significativa de hierro (11,91 y 30,04 mg / l), y calcio (6,08 y 7 09 mg / l) para el restante de los minerales el contenido fue menor: de magnesio (0,31 mg / l), potasio (0,36 y 0,72 mg / l) Mn (0,14 y 0,02 mg / l ) y fósforo sólo en las hojas (0,62 mg/l).Palabras clave: Hibiscus sabdariffa L. Minerals. Espectroscopia.
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Kazi, Atik Mubarak, and Ramasastry DVA. "Characterization of continuous Hibiscus sabdariffa fibre reinforced epoxy composites." Polymers and Polymer Composites 30 (January 2022): 096739112110609. http://dx.doi.org/10.1177/09673911211060957.
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The influence of fibre orientation on physical, mechanical and dynamic mechanical properties of Hibiscus sabdariffa fibre composites has been studied. The composites with longitudinal (0°), transverse (90°) and inclined (45°) fibre orientation were prepared using the hand layup technique. ASTM standards were used for characterization of continuous Hibiscus sabdariffa fibre composites. The composite with longitudinally placed fibres yields improved mechanical characteristics. The addition of longitudinal (0°) oriented continuous Hibiscus sabdariffa fibres to the epoxy enhances tensile strength by 460%, flexural strength by 160% and impact strength by 603% compared to neat epoxy. The longitudinal (0°) fibre oriented composite offers higher resistance to water absorption and thickness swelling compared to other types of composites. All continuous Hibiscus sabdariffa fibre epoxy composites possess an improved storage modulus than the neat epoxy resin. The glass transition temperature of continuous Hibiscus sabdariffa fibre composites is 8%–31% lower than that of neat epoxy. Scanning electron microscopy (SEM) images confirm the existence of voids in the matrix, fibre pullout and crack propagation near the fibre bundle, which indicates the stress transfer between fibre and matrix is non-uniform.
Dissertations / Theses on the topic "Hibiscus sabdariffa"
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Paul, Hélène. ""Hibiscus sabdariffa" L." Paris 5, 1995. http://www.theses.fr/1995PA05P111.
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Sindi, Hebah Abbas. "Bioactivity of anthocyanins from Hibiscus sabdariffa." Thesis, University of Leeds, 2013. http://etheses.whiterose.ac.uk/5910/.
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A systematic study on extraction of Hibiscus sabdariffa was carried out for the first time using different solvents (water, methanol, ethyl acetate and hexane) in the presence and absence of formic acid, using different extraction times and temperatures. The extracts were analysed for total phenol content, antioxidant capacity using DPPH, FRAP and TEAC assays, and total monomeric anthocyanin content. In addition, specific anthocyanins were determined using HPLC and LC-MS. The results showed the highest antioxidant capacities were obtained by extracting using water, with or without formic acid, for 10 min at 100 °C. These extracts provided the highest concentrations of cyanidin 3-sambubioside and delphinidin 3-sambubioside. Commercially available herbal teas containing H. sabdariffa were analysed. The study found that contents of total phenols, anthocyanins and antioxidant capacity were higher when using the optimal extraction procedure, suggesting that putative health benefits could be increased by altering processing methods. The partition coefficients (log p) of anthocyanins found in H. sabdariffa, were measured showed that aglycone and glucoside forms of hibiscus anthocyanins behave differently when in the presence of cell wall material. Such behaviour could, in vivo, affect the absorption and bioactivity of these anthocyanins, and therefore, their efficacy. A human crossover study investigated the effect of daily consumption for 8 weeks of a H. sabdariffa juice for 8 weeks on the blood pressure of healthy subjects (n= 29). Cranberry juice was used as the control. A significant reduction was found in systolic blood pressure (but not diastolic) compared to the baseline. No significant effect on blood pressure was seen with cranberry juice. The study suggests that regular consumption of extracts of H. sabdariffa may reduce the risk of cardiovascular disease, on the other hand people with low blood pressure should consumed it very carefully due to hypotensive effect of the extract.
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Sie, Raoul Sylvère. "Caractérisation agro-morphophysiologique et micropropagation de l’oseille de Guinée (Hibiscus Sabdariffa L. )." Brest, 2010. http://www.theses.fr/2010BRES2014.
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L’oseille de Guinée (Hibiscus sabdariffa L. ) est une plante importante en Afrique de l’Ouest pour son utilisation au niveau nutritionnel, industriel et médical. Cependant, hormis quelques études de phytotechnie, peu de travaux concernent la sélection de cette plante. En outre, aucune étude de régénération par embryogenèse somatique n’est disponible. L’objectif principal de ce travail est de caractériser la collection d’oseille de Guinée en vue à long terme, de mettre en oeuvre un programme de sélection de génotypes vigoureux, haut producteurs et résistants à certaines maladies. Par ailleurs, des perspectives de conservation et de sortie variétale de génotypes élites, nécessitent le développement de méthodes de régénération par culture in vitro. La première partie de l’étude portant sur la caractérisation morphologique et agronomique de la collection d’oseille de Guinée, a confirmé l’organisation de cette espèce en deux variétés sabdariffa et altissima dont les phénotypes sont complémentaires. H. Sabdariffa var. Sabdariffa est caractérisée par une forte vigueur végétative juvénile, une faible productivité de calices et fruits, une sensibilité faible à la photopériode et une couleur rouge des organes. H. Sabdariffa var. Altissima a une forte vigueur végétative adulte, une productivité plus élevée, une grande sensibilité à la photopériode et une couleur verte des organes. Dans une deuxième partie, les variétés sont évaluées pour leurs réactions de défense vis-à-vis des champignons pathogènes (Fusarium oxysporum et Phoma sabdariffae). Des études sur l’impact des attaques sur la croissance des plantes et certains paramètres physiologiques montrent que les individus de la variété sabdariffa sont plus résistants aux deux champignons que ceux de la variété altissima. Aucune incidence n’est observée sur la photosynthèse chez les deux variétés. Suite aux inoculations, la variété sabdariffa accumule une quantité croissante de polyphénols mais ce taux diminue chez la variété altissima. La dernière partie aborde les méthodes utilisées pour induire la formation de cals embryogènes, précédées de la mise au point d’un protocole efficace de décontamination des explants. La technique des couches cellulaires minces transversales (CCMTs) mise en oeuvre sur des plantules, permet d’obtenir des cals embryogènes après l’étude de nombreux facteurs déterminants comme le génotype (sabdariffa altissima), le milieu de culture (MS, DKW), la nature de l’expIant (racine, hypocotyle, feuille cotylédonaïre), le type (auxines, cytokinines) et la teneur des régulateurs de croissance. Les CCMTs d’hypocotyle et de feuilles cotylédonaires mis en culture dans le milieu DKW contenant les combinaisons 1/0,5 (mg/l) et 4/1 (mg/l) de 2,4-D/TDZ constituent les meilleures conditions d’induction de cals embryogènesRoselle (Hibiscus sabdariffa L. ) is an important crop in West Africa for its nutritional, industrial and medicinal uses. However, except some studies on phytotechny, there are a few report on the selection of this plant. Moreover, no study on thie in vitro regeneration by somatic embryogenesis is available. The main aim of this work is to characterize the collection of roselle for in long-term sight, to implement a programme of selection for vigorous, high yielding and resistant genotypes te certain diseases. Moreover, die conservation ami seeds production ofgood genotypes, require the development of methods of regeneration by in vitro culture. The first part of the study relating to the morphological and agronomical characterization of the collection of roselle, confirmed the organization of this species into two varieties such as sabdariffa and altissima whose phenotypes were complementary. H. Sabdariffa var. Sabdariffa was characterized by a strong early vegetative vigour, a low yielding of calyx and fruits, a low photoperiod susceptibility and a red color of plants. H. Sabdariffa var. Altissima had a strong adult vegetative vigour, a higher yielding, a high photoperiod susceptibility and a green color of the plant. In a second part, the varieties were evaluated for their defense reactions against to pathogenic fungi (Fusarium oxysporum and Phoma sabdariffae). Studies ou the impact of the attacks on the growth of the plants and certain physiological parameters, showed that the individuals of the sabdariffa variety were more resistaut to both fungi than those of the altissima variety. No incidence was observed on both varieties photosynthesis. Following die inoculations, the sabdariffa variety accumulated an increasing quantity of polyphenols but this rate decreases in the altissima variety. The last part describes the methods used to induce the formation of embryogenic calli, preceded by the development of an efficient protocol of decontamination of explants. The technique of the thin Transversal Cell Layers (tTCLs) implemented on seedlings, enabled to obtain some embryogenic calli after the study of many determining factors such as the genotype (sabdariffa, altissima), the culture medium (MS, DKW), the nature of the explant (root, hypocotyle, cotyledon), the type (auxines, cytokinines) and the content of the growth regulaters. The tTCLs from hypocotyl and cotyledon in culture medium DKW containing combinations 1/0,5 (mg/l) and 4/1 (mg/l) of 2,4-D/TDZ constituted the best conditions of induction of the embryogenic calli
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Sinela, André Mundombe. "Etude des mécanismes réactionnels et des cinétiques de dégradation des anthocyanes dans un extrait d’Hibiscus sabdariffa L." Thesis, Montpellier, SupAgro, 2016. http://www.theses.fr/2016NSAM0036/document.
Full textAbstract:
Les calices séchés d’Hibiscus sabdariffa L. sont traditionnellement utilisés en Afrique pour la production de boissons par macération dans l’eau. Cette matière première, riche en anthocyanes, est aussi connue dans l’industrie agro-alimentaire comme source de colorants naturels. Toutefois, la couleur des extraits obtenus évoluent rapidement au cours du temps ce qui nuit au développement de ces produits. Afin de mieux caractériser et de mieux comprendre l’instabilité de la couleur, ce travail propose une étude cinétique et mécanistique de la dégradation des anthocyanes durant la conservation d’un extrait d’H. sabdariffa. La caractérisation biochimique de l’extrait a notamment permis d’identifier les polyphénols majoritaires (delphinidine 3-O-sambubioside Del-3Sb, cyanidine 3-O-sambubioside Cya-3Sb, acides caféoylquiniques) et à mis en évidence la présence de métaux connus comme potentiels catalyseurs d’oxydation (Fe, Cu, Mn). Les cinétiques de dégradation des anthocyanes dans l’extrait ont été suivies par CLHP-DAD entre 4 et 37°C pendant 60 j. Elles peuvent être représentées par un modèle d’ordre 1. La Del-3Sb (Ea= 90 kJ.mol-1) est plus sensible à l’augmentation de la température que la Cya-3Sb (Ea= 80 kJ.mol-1). L’influence de différents facteurs sur la dégradation des anthocyanes a été étudiée dans des solutions modèles simplifiées. La constante de vitesse de dégradation de la Del-3Sb en solution modèle contenant du Fe (III), Cu (II) et Mn (II) à des concentrations similaires à celles de l’extrait, est proche de celle mesurée dans l’extrait. Celle de la Cya-3Sb est 40 % plus faible que dans l’extrait. L’augmentation de la concentration en Fe de 1 à 13 mg.L-1 multiplie environ 3 fois les vitesses de dégradation des anthocyanes. L’ajout d’acide chlorogénique à une solution modèle contenant du Fe augmente la vitesse de dégradation de la Cya-3Sb de 42 %. Un effet inverse est observé dans le cas de Del-3Sb (diminution de 47%). La teneur en oxygène dissous n’a pas d’influence sur les vitesses de dégradation. Deux mécanismes de dégradation des anthocyanes ont été mis en évidence : le mécanisme de scission, représentant une voie minoritaire (10% des anthocyanes dégradés) avec production de phloroglucinaldéhyde, d’acide gallique (issu de Del-3Sb) et protocatéchique (issu de Cya-3Sb) et un mécanisme de condensation avec formation de polymères bruns qui est favorisé par l’augmentation de la concentration en Fe et le mélange Fe, Cu et Mn. Les conclusions de l’ensemble du travail aboutissent à des perspectives sur l’étude de l’impact d’autres composés présents dans l’extrait (sucres, acides aminés) ainsi qui l’identification et la quantification des polymères brunsDried calyx of Hibiscus sabdariffa L. are traditionally used in Africa for beverage production by maceration in water. This raw material, rich in anthocyanins, is also known in the food industry as a source of natural dyes. However, the color of extracts obtained quickly changes over time which affects the development of these products. To better characterize and understand the instability of color, this work provides a mechanistic and kinetic study of the degradation of anthocyanins during the conservation of an extract from H. sabdariffa. Biochemical characterization of the extract allowed to identify predominant polyphenols (delphinidin 3-O-sambubioside Del-3Sb, cyanidin 3-O-sambubioside Cya-3Sb and caffeoylquinic acids) and highlighted the presence of metals known as potential oxidation catalysts (Fe, Cu, Mn). Kinetics of degradation of anthocyanins in the extract were followed by HPLC-DAD between 4 and 37 ° C for 60 days. It can be represented by a first order model. Del-3Sb (Ea = 90 kJ mol-1) is more sensitive to temperature increase than Cya-3Sb (Ea = 80 kJ.mol-1). Influence of different factors on the degradation of anthocyanins was studied in simplified model media. Rate constant of degradation (k) of Del-3Sb on model media containing Fe (III), Cu (II) and Mn (II) at similar concentrations to those of the extract was similar to that measured in the extract. For Cya-3Sb it was 40% lower than in the extract. Increasing Fe concentration of 1 to 13 mg.L 1 increased by about 3-fold the k of anthocyanins. Adding chlorogenic acid in a model media containing Fe increased k of Cya-3Sb 42%. Opposite effect was observed for Del-3Sb (47% decrease). Dissolved oxygen content has no influence on k of anthocyanins. Two mechanisms of degradation of anthocyanins have been identified: the scission mechanism, representing a minority pathway (10% of degraded anthocyanins) with production of phloroglucinaldehyde, gallic acid (from Del-3Sb) and protocatechuic (from Cya -3Sb). The other mechanism is condensation with formation of brown polymers, it is promoted by increasing of concentration of Fe was and mixture of Fe, Cu and Mn. Conclusions led to perspectives on study of impact of other compound in the extract (sugar, amino-acids) as well as identification and quantification of brown polymers
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MALACRIDA, ALESSIO. "EVALUATION OF ANTITUMORAL EFFECTS OF HIBISCUS SABDARIFFA ON MULTIPLE MYELOMA CELLS." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2017. http://hdl.handle.net/10281/158152.
Full textAbstract:
Hibiscus Sabdariffa (HS) is a plant of the Malvacee family commonly cultured in tropical and subtropical countries. It is mainly known as the main ingredient for the preparation of cold drink called Karkadè. Calices and leaves of HS plant are also used in folk medicine thanks to their antioxidant and anti-inflammatory properties. In recent years, HS has also gained great interest as a possible antitumoral agent.
In the present PhD project, we evaluated the antitumoral effects of HS against multiple mye-loma cells in vitro. Multiple myeloma is the most frequent hematological malignancy world-wide. In recent years, new drugs have increased the survival expectancy of patients. Despite this, new therapeutic approaches are necessary, especially for high multiple myeloma hetero-geneity and for relapsed or refractory multiple myeloma.
The project was organized in three distinct phases:
1- Evaluation of antitumoral effects of HS against RPMI 8226 human multiple myeloma cells. We demonstrated by MTT and Trypan blue assays that a total HS extract (HSE) and one of its fraction obtained by liquid-liquid extraction (HSEC) were able to impair cell viability of human multiple myeloma RPMI 8226 in a dose and time dependent manner. HSE cell viability reduction was due to a cytostatic action, while HSEC was more cytotoxic and induced a caspase dependent apoptosis. Moreover, both HSE and HSEC impaired cell migration and invasion of RPMI 8226 cells in a Boyden chamber as-say. We also demonstrated in in vitro model of neurotoxicity (dorsal root ganglia model) that HSE and HSEC concentrations used in our experiments were not neurotoxic. In RPMI 8226 cells autophagy and proteasome activity were impaired by both HSE and HSEC. MAPK p38 activation was observed in the first 6h of treatment, while ERK 1 and ERK 2 activation occurred between 16 and 48h.
2- Evaluation of combinations between Bortezomib (BTZ) and HSE or HSEC against RPMI 8226 multiple myeloma cells. We evaluated several combinations between BTZ and HSE or HSEC (simultaneous, not-simultaneous treatment and pretreatment) using MTT assay to assess their effectiveness. Among all evaluated combinations, only the 24h BTZ 1nM pretreatment followed by HSE or HSEC treatment resulted more effective than BTZ or HSE or HSEC single treatment in reducing cell viability. This combination was not neurotoxic in the dorsal root ganglia model.
3- Isolation and characterization of HSEC molecules responsible of the antitumoral ef-fect. Using a bioguided method, we isolated several fractions from HSEC. Fractions were obtained by flash column chromatography or by resin use. Molecular characterization was performed by HPLC, NMR or mass spectrometry, while biological activity was screened in human multiple myeloma RPMI 8226 cells by MTT and proteasome activity assay. We isolated three fractions with a first fractionating process that keep their activ-ity on RPMI 8226 cells, but that are not completely pure. In a second fractionating, we isolated a highly pure fraction with a significant activity on RPMI 8226 cell viability. We also characterized this fraction by both a molecular and biological point of view.
In conclusion, we demonstrated the antitumoral effect of HS in vitro against RPMI 8226 multiple myeloma cells. We also found a new therapeutic combination between BTZ and HS that enhanced their antitumoral effect when compared to single treatments. Moreover, we also isolated one of the molecules that are involved in the antitumoral effect of HS.
The results of my PhD project showed that HS could be a promising chemotherapeutic agent, but further studies are still needed.Hibiscus Sabdariffa (HS) is a plant of the Malvacee family commonly cultured in tropical and subtropical countries. It is mainly known as the main ingredient for the preparation of cold drink called Karkadè. Calices and leaves of HS plant are also used in folk medicine thanks to their antioxidant and anti-inflammatory properties. In recent years, HS has also gained great interest as a possible antitumoral agent. In the present PhD project, we evaluated the antitumoral effects of HS against multiple mye-loma cells in vitro. Multiple myeloma is the most frequent hematological malignancy world-wide. In recent years, new drugs have increased the survival expectancy of patients. Despite this, new therapeutic approaches are necessary, especially for high multiple myeloma hetero-geneity and for relapsed or refractory multiple myeloma. The project was organized in three distinct phases: 1- Evaluation of antitumoral effects of HS against RPMI 8226 human multiple myeloma cells. We demonstrated by MTT and Trypan blue assays that a total HS extract (HSE) and one of its fraction obtained by liquid-liquid extraction (HSEC) were able to impair cell viability of human multiple myeloma RPMI 8226 in a dose and time dependent manner. HSE cell viability reduction was due to a cytostatic action, while HSEC was more cytotoxic and induced a caspase dependent apoptosis. Moreover, both HSE and HSEC impaired cell migration and invasion of RPMI 8226 cells in a Boyden chamber as-say. We also demonstrated in in vitro model of neurotoxicity (dorsal root ganglia model) that HSE and HSEC concentrations used in our experiments were not neurotoxic. In RPMI 8226 cells autophagy and proteasome activity were impaired by both HSE and HSEC. MAPK p38 activation was observed in the first 6h of treatment, while ERK 1 and ERK 2 activation occurred between 16 and 48h. 2- Evaluation of combinations between Bortezomib (BTZ) and HSE or HSEC against RPMI 8226 multiple myeloma cells. We evaluated several combinations between BTZ and HSE or HSEC (simultaneous, not-simultaneous treatment and pretreatment) using MTT assay to assess their effectiveness. Among all evaluated combinations, only the 24h BTZ 1nM pretreatment followed by HSE or HSEC treatment resulted more effective than BTZ or HSE or HSEC single treatment in reducing cell viability. This combination was not neurotoxic in the dorsal root ganglia model. 3- Isolation and characterization of HSEC molecules responsible of the antitumoral ef-fect. Using a bioguided method, we isolated several fractions from HSEC. Fractions were obtained by flash column chromatography or by resin use. Molecular characterization was performed by HPLC, NMR or mass spectrometry, while biological activity was screened in human multiple myeloma RPMI 8226 cells by MTT and proteasome activity assay. We isolated three fractions with a first fractionating process that keep their activ-ity on RPMI 8226 cells, but that are not completely pure. In a second fractionating, we isolated a highly pure fraction with a significant activity on RPMI 8226 cell viability. We also characterized this fraction by both a molecular and biological point of view. In conclusion, we demonstrated the antitumoral effect of HS in vitro against RPMI 8226 multiple myeloma cells. We also found a new therapeutic combination between BTZ and HS that enhanced their antitumoral effect when compared to single treatments. Moreover, we also isolated one of the molecules that are involved in the antitumoral effect of HS. The results of my PhD project showed that HS could be a promising chemotherapeutic agent, but further studies are still needed.
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Omoarukhe, Esereosa D. "Natural processing for beverages : from a Hibiscus sabdariffa (Roselle) beverage perspective." Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/78761/.
Full textAbstract:
The beverage industry is tending towards the production of healthier, low calorie beverages containing only naturally derived ingredients. The use of these ingredients presents an opportunity for a rise in functional beverages but could also present beverage quality challenges. Using Hibiscus sabdariffa (Roselle) extracts, known for its functional properties, this research investigates some quality considerations that may result due to relevant changes to the production, storage and consumption of the beverage to suit clean label considerations. These issues relate to processing, calories reduction and stability. Several research questions have been generated under these categories and addressed in subsequent chapters of the thesis. From a Roselle beverage perspective, pasteurisation (in-bottle, 85oC for 20 minutes) and cold storage (below 4oC) were satisfactory for processing of the beverage. Stevia Rebaudioside A (SRA) was explored as a sugar replacer and displayed promising results such as improving the sensory attributes of the unsweetened Roselle extract. In physical and chemical tests, it matched the attributes of unsweetened beverages. However, it did not perform as well as sugar in either consumer studies and when combined with spice flavours. The spices (cinnamon, ginger and cloves) used for their flavouring and preserving properties did not improve consumer liking of the beverages in general but cinnamon demonstrated stabilising effects on the anthocyanins in a sugar sweetened Roselle beverage through a suspected co-pigmentation mechanism. Furthermore, cinnamon and ginger were deemed congruent with the Roselle flavour profile based on their performance in the consumer study. Further investigative work on spice and sweetener synergies and the understanding of their mechanisms were recommended.
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Maciel, Mônica Jachetti. "Avaliação do extrato alcoólico de hibisco (hibiscus sabdariffa l.) como fator de proteção antibacteriana e antioxidante em alimentos." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/29544.
Full textAbstract:
O hibisco (Hibiscus sabdariffa L.) além de possuir propriedades antioxidantes e antimicrobianas, é utilizado como planta medicinal e alimento funcional nos países tropicais. Através de Testes de Diluição em Sistema de Tubos Múltiplos determinou-se a Intensidade de Atividade de Inibição Bacteriana (IINIB/Bacteriostasia) e a Intensidade de Atividade de Inativação Bacteriana (IINAB/Bactericidia) de extrato alcoólico de dois acessos de hibisco, a saber: Palmares do Sul/RS e Porto Alegre/RS sobre inóculos padronizados de Enterococcus faecalis (ATCC 19433), Escherichia coli (ATCC 11229), Salmonella Enteritidis (ATCC 11076) e Staphylococcus aureus (ATCC 25923). Paralelamente, o teor de polifenóis totais e de antocianinas nos cálices e nos frutos com sementes do hibisco foi determinado. A atividade antimicrobiana do extrato alcoólico de cálices, em ambos os acessos, apresentou diferença positiva significativa quando relacionada ao extrato alcoólico dos frutos com sementes. Salmonella Enteritidis foi a bactéria mais sensível ao extrato alcoólico de cálices do hibisco enquanto a mais resistente foi Staphylococcus aureus, independente da variável acesso, considerando somente a estrutura vegetal. Em relação ao extrato alcoólico dos frutos com sementes, Escherichia coli demonstrou a maior sensibilidade e Staphylococcus aureus a maior resistência. Os valores de polifenóis totais e de antocianinas do extrato alcoólico de cálices apresentaram diferença significativa entre si e foram superiores ao extrato alcoólico dos frutos com sementes. Possivelmente existe uma relação direta entre a concentração de antocianina e a atividade antibacteriana em diferentes estruturas vegetais do hibisco.The hibiscus (Hibiscus sabdariffa L.) has antioxidant and antimicrobial properties and it is utilized as functional food and medicinal plant in tropical countries. Through of Dilution Testing in Multiple Tubes System, it were determined the intensity of bacterial inhibition activity (IINIB/ Bacteriostasy) and the intensity of bacterial inactivation activity (IINAB/ Bactericidie) of alcoholic extracts of two accesses of hibiscus, known as: Palmares do Sul/RS and Porto Alegre/RS on standardized inoculum of Enterococcus faecalis (ATCC 19433), Escherichia coli (ATCC 11229), Salmonella Enteritidis (ATCC 11076) and Staphylococcus aureus (ATCC 25923). At the same time, the total content of polyphenols and anthocyanins in the calyxes and fruits with seeds hibiscus was determined. The antimicrobial activity of alcoholic extract of the calyxes in both accesses showed a significant positive difference when related to the alcoholic extract of the fruits with seeds. Salmonella enteritidis was the most sensitive bacteria to the alcoholic extract of calyxes of the hibiscus while the most resistant was Staphylococcus aureus, independent of the variable access, considering only the plant structure. In relation to the alcoholic extract of the fruits with seeds, Escherichia coli showed the highest sensitivity and Staphylococcus aureus the highest resistence. Total polyphenols and anthocyanins of alcoholic extract of calyxes‟s values showed a significant difference and they were superior to alcohol extract of fruits with seeds. Possibly there is a direct relationship between the concentration of anthocyanin and antibacterial activity in different structures of the hibiscus plant.
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Piovesana, Alessandra. "Extração, identificação, quantificação e microencapsulamento por atomização e liofilização de compostos bioativos dos cálices de hibisco (hibiscus sabdariffa l.)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2016. http://hdl.handle.net/10183/151290.
Full textAbstract:
O interesse pela extração dos compostos bioativos, a partir de fontes naturais, para o emprego na produção de alimentos funcionais tem aumentado, devido, principalmente, à crescente demanda por parte dos consumidores, por produtos mais saudáveis e que possam trazer benefícios à saúde. Dentre as fontes naturais de compostos bioativos, destaca-se o hibisco (Hibiscus sabdariffa L.), que é rico em antocianinas, flavonoides, ácidos fenólicos, carotenoides, dentre outros. Entretanto, quando os compostos bioativos são separados de suas matrizes, estes se tornam altamente instáveis frente a diversos fatores ambientais, necessitando serem protegidos. O recobrimento por microencapsulamento é uma alternativa para retardar a degradação desses compostos. Este estudo teve como objetivo a extração, identificação, quantificação e microencapsulamento por atomização e liofilização dos compostos bioativos dos cálices do hibisco. Primeiramente, foi realizada a extração exaustiva total dos carotenoides e compostos fenólicos por meio de solventes orgânicos, para a identificação e quantificação desses compostos. Também foi estudada a extração de antocianinas e demais compostos fenólicos por meio de solvente aquoso acidificado (ácido cítrico 2 %, p/v). A partir do melhor tratamento de extração, o extrato obtido foi microencapsulado mediante atomização e liofilização, empregando goma arábica (GA), goma guar parcialmente hidrolisada (GGPH) e polidextrose (PD) como agentes encapsulantes, na concentração de 10%. Os carotenoides e compostos fenólicos foram identificados e quantificados por HPLC-DAD-MS/MS (cromatografia líquida de alta eficiência com detecção por arranjo de diodos e espectrometria de massa). Vinte e um carotenoides foram encontrados, dos quais, quinze foram identificados. O total de carotenoides nos cálices de hibisco foi de 641,38 ± 23,61 μg/100 g massa fresca, sendo a all-trans-luteína e o all-trans--caroteno os compostos majoritários, representando 49 e 23%, respectivamente. Para os compostos fenólicos, foram encontrados vinte compostos, dos quais, catorze foram identificados. As antocianinas foram os compostos majoritários nos cálices de hibisco, sendo que a delfinidina 3-sambubiosídeo e cianidina 3-sambubiosídeo representaram 41 e 13% do total de compostos fenólicos, respectivamente. Dentre os ácidos fenólicos, os componentes majoritários foram o ácido 3-cafeoilquínico e ácido 5-cafeoilquínico, representando 15 e 13% do total de compostos fenólicos, respectivamente. Para a extração aquosa acidificada, foi utilizado um planejamento experimental fatorial fracionado (24-1), com quatro fatores: concentração de enzima, temperatura, velocidade de agitação e tempo de extração. A partir da ANOVA, os efeitos principais e de interação foram avaliados, tendo como respostas Chroma, antocianinas monoméricas totais (TMA), capacidade redutora, ABTS e compostos fenólicos. A partir dos resultados, o melhor tratamento foi: 55 °C, 50 μL de enzima/1000 g extrato, 400 rpm e 4 horas de extração, obtendo-se nessa condição de extração 3,82 mg/g extrato em base seca para TMA e 17,59 mg/g de extrato em base seca para compostos fenólicos totais, que resultou em capacidade antioxidante de 7,72 μmol Eq. Trolox/g de extrato em base seca, avaliado por ABTS e de 3,96 mg GAE/g de de extrato em base seca, avaliado pela capacidade redutora. Este extrato foi empregado no estudo de encapsulamento, por atomização (140 ºC) e liofilização (-68 ºC por 24 horas), utilizando GA, GGPH e PD como encapsulantes. Observou-se que o melhor tratamento foi por liofilização empregando GA como encapsulante, resultando em 2,83 mg/g amostra em base seca para TMA, capacidade antioxidante de 2,98 mg GAE/g amostra em base seca e 5.67 μmol Eq. Trolox/g amostra em base seca, avaliados por capacidade redutora e ABTS, respectivamente. Entretanto, quando foram avaliadas as propriedades físicas e morfológicas dos pós, as amostras elaboradas por atomização e usando GA e GGPH apresentaram os melhores desempenhos, onde os valores de solubilidade, higroscopicidade e umidade foram de 95,8 e 95,2%, 31,3 e 28,9%, 1,9 e 2,4%, respectivamente. Para a temperatura de transição vítrea (Tg), os tratamentos que utilizaram GA e GGPH nos dois métodos de encapsulamento, tiveram os maiores valores de Tg, variando de 10,9 a 17,4 ºC. Já para os tratamentos que utilizaram a PD como material de parede, os valores foram de (0,7 °C), tanto na atomização como na liofilização. Na microscopia também foi observado um melhor desempenho nas micropartículas atomizadas usando GA e GGPH, as quais mostraram partículas mais esféricas e sem tendência de atração e aderência entre si. Em relação ao diâmetro médio de partícula (D[4, 3]), os tratamentos liofilizados tiveram partículas maiores que os atomizados, variando de 101,7 a 143,1 μm para os liofilizados, e de 5,4 a 7,3 μm para os atomizados. Quanto ao span, o qual avalia distribuição de tamanho de partícula, variou de 1,90 a 2,00 para as amostras atomizadas e de 3,06 a 3,19 para as amostras liofilizadas, indicando que houve uma boa uniformidade na distribuição de tamanho de partícula. Conclui-se que o hibisco é uma matriz com ampla composição de compostos bioativos e tem potencial para aplicação em alimentos.The interest in the extraction of bioactive compounds from natural sources, for use in the production of functional foods has increased, mainly due to the growing demand by consumers for healthier products and can bring health benefits. Among the natural sources of bioactive compounds, stands out the hibiscus (Hibiscus sabdariffa L.), which is rich in anthocyanins, flavonoids, phenolic acids, carotenoids, among others. However, when the bioactive compounds are separated from their matrix, they become highly unstable against various environmental factors and need to be protected. The coating by microencapsulation is an alternative to slow the degradation of these compounds. This study aimed at the extraction, identification, quantification and microencapsulation by spray drying and freeze drying of bioactive compounds of hibiscus calyces. Firstly, a thorough exhaustive extraction of carotenoids and phenolic compounds by organic solvents was performed for identification and quantification of these compounds. The extraction of anthocyanins was also studied along with other phenolic compounds by an aqueous solvent acidified (2% citric acid, w/v). From the best treatment for extraction, the extract obtained was microencapsulated by spray drying and freeze drying using Arabic gum (GA), partially hydrolyzed guar gum (PHGG) and polydextrose (PD) as encapsulating agents in a concentration of 10%. Carotenoids and phenolic compounds were identified and quantified by HPLC-DAD-MS/MS (high-performance liquid chromatography with diode array detection and mass spectrometry). Twenty-one carotenoids were found, of which fifteen were identified. The total carotenoids in hibiscus calyces was 641.38 ± 23.61 mg/100 g fresh weight, with the all-trans-lutein and all-trans-β-carotene the major compounds, representing 49 and 23%, respectively. Regarding the phenolic compounds it was found twenty of those, of which fourteen have been identified. Anthocyanins were the main components in the hibiscus calyces, and delphinidin and cyanidin 3-sambubioside 3-sambubioside represented 41 and 13% of total phenolic compounds, respectively. Among the phenolic acids, the major components were the 3-caffeoylquinic acid and 5-caffeoylquinic acid, representing 15 and 13% of total phenolic compounds, respectively. For acidified aqueous extraction, we used a fractional factorial design (24-1) with four factors: enzyme concentration, temperature, stirring speed and extraction time. From the ANOVA, the main and interaction effects were assessed as answers: Chroma, total anthocyanins monomeric (TMA), reducing capacity, ABTS and phenolic compounds. From the results, the best treatment was with 55 °C, 50 μL of enzyme/1000 g extract, 400 rpm and 4 hours of extraction, it was obtained in this extraction condition 3.82 mg/g extract on a dry basis for TMA and 17.59 mg/g extract on a dry basis for phenolic compounds, which resulted in antioxidant capacity of 7.72 μmol Eq. Trolox/g extract on a dry basis, evaluated by ABTS and 3.96 mg GAE/g extract on a dry basis, assessed by reducing capacity. This extract was used for the encapsulation study, by spray drying (140 °C) and freeze drying (-68 ° C for 24 hours) using GA, PHGG, and PD as encapsulants. It was observed that the best treatment is by freeze drying using GA as encapsulant, resulting in 2.83 mg/g sample on dry basis for TMA, antioxidant capacity of 2.98 mg GAE/g sample on dry basis and 5.67 μmol Eq. Trolox/g sample on dry basis, evaluated by reducing capacity and ABTS, respectively. However, when we evaluated the physical and morphological properties of powders, samples prepared by spray drying and using GA and PHGG showed the best performance, and the values for solubility, hygroscopicity and moisture were 95.8 and 95.2%, 31.3 and 28.9%, 1.9 and 2.4%, respectively. For the glass transition temperature (Tg), treatments with GA and PHGG on both encapsulation methods had high Tg values ranging from 10.9 to 17.4 °C. As for treatments of PD as wall material, the values were (0.7 °C), both the spray drying as in freeze drying. In microscopy was also observed improved performance in spray-dried microparticles using GA and PHGG, which showed more spherical particles and with no tendency to attract and adhere to each other. Regarding the average particle diameter (D [4, 3]), the freeze-dried treatments had higher spray-dried particles ranging from 101.7 to 143.1 μm for freeze-dried, and 5.4 to 7.3 μm for spray-dried. As the span, which assesses particle size distribution ranged from 1.90 to 2.00 for spray-dried samples and 3.06 to 3.19 for the freeze-dried samples, indicating that there was a good uniformity in the size in the distribution of the size of the particle. It follows that hibiscus is a matrix with broad composition and bioactive compounds have potential for application in foods.
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Cassol, Liliana. "Extração de compostos bioativos do hibisco (Hibiscus sabdariffa L.) por micro-ondas e seu encapsulamento por atomização e liofilização." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/179787.
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Os cálices do hibisco possuem uma grande quantidade de compostos bioativos responsáveis pela sua atividade antioxidante. O presente trabalho teve como objetivos a obtenção de extratos contendo esses compostos bioativos em solução aquosa com 2 % de ácido cítrico por extração assistida por micro-ondas (EAM) e o encapsulamento desses extratos por atomização e liofilização utilizando polidextrose (PD), proteína isolada do soro de leite (WPI) e a mistura destes na concentração de 10 %. Previamente foram estudados três métodos de extração, o primeiro usando somente EAM a 200, 300 e 700 W de potência, e tempos de 2, 5 e 8 minutos; o segundo consistiu de dois períodos, a extração aquosa ácida com tempos de 1, 2, 4, 6, 18 e 24 horas seguida de EAM nas potências de 200, 300 e 700 W; o terceiro consistiu de EAM seguida de extração aquosa ácida, nos mesmos tempos e potências citados para o segundo método. Os resultados indicaram que a melhor condição do primeiro método foi a 700 W e 8 min, do segundo método realizada a 6 horas de extração aquosa ácida, seguida de EAM a 700 W por 8 min e do terceiro método, EAM a 700 W por 8 min seguida de 6 horas de extração aquosa ácida. Quando os três métodos foram comparados, a melhor condição de extração foi aquela obtida no terceiro método: 1,63 mg delfinidina-3-sambubiosídeo · g-1; 29,62 mg EAG · g-1; 133,25 μmol ET · g-1 para antocianinas, fenólicos totais e atividade antioxidante por ABTS, respectivamente. Para avaliar o efeito da extração obtida somente por EAM, os extratos obtidos por extração exaustiva com metanol por 25 min e EAM a 700 W e 8 min foram quantificados por HPLC-DAD-ESI-MS/MS, sendo encontrados 13 compostos (6 ácidos fenólicos, 2 antocianinas e 5 flavonóides derivados da quercetina, kaempferol e miricetina). Os compostos fenólicos majoritários foram o ácido 3-cafeoilquínico (2,58 e 1,32 mg · g-1) e ácido 5-cafeoilquínico (1,71 e 0,90 mg · g-1) para extração exaustiva e EAM, respectivamente. Esse mesmo extrato (700 W e 8 min) foi encapsulado por atomização (160 °C) e liofilização (- 68 °C por 54 horas). Os pós obtidos foram avaliados quanto aos teores de compostos fenólicos totais, antocianinas monoméricas totais, atividade antioxidante (ABTS, DPPH e HRSA), medidas por análises espectrofotométricas, atividade de água, umidade, higroscopicidade, solubilidade, eficiência de encapsulação, cor, análise termogravimétrica, temperatura de transição vítrea, espectroscopia de infravermelho com transformada de Fourier (FTIR) e microestrutura (MEV). Os pós atomizados tiveram menor atividade de água (0,14 a 0,17), umidade (3,4 a 4,5 %), higroscopicidade (23,9 a 34,1 %), solubilidade (86 a 98,2 %) e eficiência de encapsulação (51,62 a 84,52 %) do que os pós liofilizados. Os resultados do FTIR mostraram que os encapsulantes não interagiram quimicamente, visto que não foram observados mudanças na frequência dos picos; as provas termogravimétricas indicaram que os pós apresentaram a mesma tendência nas perdas de massa. Na análise de microestrutura foi observado um melhor desempenho nas micropartículas atomizadas com PD, as quais mostraram partículas mais esféricas e sem tendência de atração e aderência entre si. Foram obtidas retenções de 38 a 77 % para antocianinas monoméricas totais, 42 a 89 % para compostos fenólicos totais, e entre 33 e 90 % para atividade antioxidante nos pós obtidos. O pó encapsulado liofilizado com 10 % de polidextrose mostrou uma maior retenção de antocianinas (77 %), atividade antioxidante por DDPH (90 %) e HRSA (74 %), entretanto com maior higroscopicidade (39,4 %). As provas aceleradas de estocagem (umidades relativas de 75 e 90 % em temperaturas de 40 e 60 °C) realizadas em todos os pós encapsulados, após 30 dias, indicaram que o tratamento liofilizado com 10 % de PD foi o que apresentou melhores resultados a essas condições, retendo 75 % dos compostos fenólicos, com atividades antioxidantes medidas por ABTS, DPPH e HRSA de 75, 90 e 74 %, respectivamente, existentes no extrato original. O pó obtido tem potencial para aplicação em alimentos, portanto, devido ao hibisco ser uma matriz com ampla composição de compostos bioativos.The hibiscus calyces contend a high quantity of bioactive compounds responsible for their antioxidant activity. The present paper was aimed the production of extracts containing those bioactive compounds in acidified aqueous solution 2 % of citric acid by microwave assisted extraction (MAE) and the encapsulation of those extracts by spray drying and freeze-drying using polydextrose (PD), whey protein isolate (WPI) and their mixture in the concentration of 10 %. Previously three methods of extraction were studied, the first using only MAE at 200, 300 and 700 W of power, and times of 2, 5 and 8 minutes; the second consisted of two steps, the acid aqueous extraction with times of 1, 2, 4, 6, 18 and 24 hours followed by MAE at the powers of 200, 300 and 700 Watts; the third consisted of MAE followed by acid aqueous extraction, in the same times and powers mentioned for the second method. The results indicated that the best condition of the first method was 700 W and 8 minutes, the second method performed at 6 hours of acid aqueous extraction, followed by MAE at 700 W for 8 minutes and the third method, MAE at 700 W for 8 minutes followed by 6 hours of acid aqueous extraction. When the three methods are compared, the best condition of extraction was obtained in the third method: 1.63 mg delphinidin-3-sambubioside · g-1; 29.62 mg GAE · g-1; 133.25 μmol TE · g-1 for total monomeric anthocyanins, total phenolic compounds and antioxidant activity by ABTS, respectively. To evaluate the effect of the extraction obtained only by MAE, the extracts obtained by exhaustive extraction with methanol for 25 minutes and MAE at 700 W and 8 minutes were quantified by HPLC-DAD-ESI-MS/MS, was found 13 compounds (6 phenolic acids, 2 anthocyanins and 5 flavonoids derived from quercetin, kaempferol and myricetin). The phenolic compounds majorities were acid 3-caffeoylquinic (2.58 e 1.32 mg · g-1) and acid 5-caffeoylquinic (1.71 e 0.90 mg · g-1) for exhaustive extraction and MAE, respectively. That same extract (700 W and 8 minutes) was encapsulated by spray drying (160 ºC) and freeze-drying (- 68 °C for 54 hours). The obtained powders were evaluated about the levels of total phenolic compounds, total monomeric anthocyanins, antioxidant activity (ABTS, DPPH e HRSA), measured by spectrophotometric analysis, water activity, moisture, hygroscopicity, solubility, encapsulation efficiency, color, thermogravimetric analysis, glass transition temperature, Fourier transform infrared spectroscopy (FTIR) and microstructure (MEV). The spray dried powders had lower water activity (0.14 to 0.17), moisture (3.4 to 4.5 %), hygroscopicity (23.9 to 34.1 %), solubility (86 to 98.2 %) and encapsulation efficiency (51.62 to 84.52 %) than the freeze-dried powders. The results of FTIR showed that the encapsulants did not interact chemically, since changes were not observed on the frequency of the peaks; the thermogravimetric tests indicated that the powders presented the same tendency on the mass loss. On the microstructure analysis a better perform was observed on the spray dried microparticles with PD, which showed more spherical particles and with no tendency of attraction and adherence between them. Were obtained retentions of 38 to 77 % for total monomeric anthocyanins, 42 to 89 % for total phenolic compounds and between 33 and 90 % for antioxidant activity in the obtained powders. The encapsulated power by freeze-drying, with 10 % of polydextrose, was showed higher retention of anthocyanins (77 %), antioxidant activity by DDPH (90 %) and HRSA (74 %), however with higher hygroscopicity (39.4 %). The accelerated tests of storage (relative humidity of 75 and 90 % in temperatures of 40 and 60 ºC) performed in all the encapsulated powders, after 30 days, indicated that the freeze-drying treatment with 10 % of PD has the best behavior in those conditions, retaining 75 % of the phenolic compounds, with antioxidant activities measured by ABTS, DPPH and HRSA of 75, 90 and 74 %, respectively, present in the original extract. The obtained powder has potential for application in foods, therefore, due to the hibiscus being a matrix with ample composition of bioactive compounds.
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Cissé, Mady. "Couplage de procédés membranaires pour la production d’extraits anthocyaniques : application à Hibiscus sabdariffa." Thesis, Montpellier, SupAgro, 2010. http://www.theses.fr/2010NSAM0035/document.
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Hibiscus sabdariffa L. est une plante vivace herbacée localisée dans les zones tropicales et subtropicales des deux hémisphères. Au Sénégal, où elle a été introduite au 19ème siècle, H. sabdariffa, encore appelé bissap ou roselle, est cultivé sur l'ensemble du territoire et exploité principalement pour ses calices. Une boisson désaltérante est traditionnellement élaborée à partir des calices séchés par extraction à l'eau. La caractérisation physico-chimique et biochimique des calices nous a tout d'abord permis de mieux évaluer le potentiel de ce produit. Ainsi, les calices contiennent entre 767 et 1480 mg.100g -1 d'anthocyanes et entre 1347 et 3736 mg.100g-1 de polyphénols totaux. Ils présentent un pouvoir antioxydant voisin de 260 µmolTrolox.g-1. L'acide malique y est l'acide organique majoritaire avec une teneur pouvant atteindre 2,3 g.100g-1. De part ces caractéristiques, l'extrait aqueux de calices d'H. sabdariffa constitue une excellente source d'anthocyanes. Le travail s'est ensuite focalisé sur le procédé d'obtention de cet extrait. L'étude de l'extraction solide-liquide a été réalisée à partir de calices séchés et d'eau à des températures comprises entre 25 et 90 °C. Un rendement d'extraction en anthocyanes maximum de 88 % a été obtenu à 25 °C avec un ratio calice/eau de 1/25. La réduction de la taille des particules et l'augmentation de la température diminuent le temps d'extraction mais n'affectent pas le rendement d'extraction. Un modèle d'extraction solide-liquide incluant les cinétiques de dégradation thermique des anthocyanes a été proposé puis validé. La microfiltration tangentielle sur membrane céramique de diamètre moyen de pores 0,2 µm a permis de produire un extrait stérilisé à froid, stable pendant 90 j à 20 °C. Nous avons montré à ce niveau que la pression transmembranaire optimisée à un facteur de réduct ion volumique (FRV) égal à 1 n'est plus optimale lorsque le FRV augmente. Pour concentrer les anthocyanes présents dans l'extrait, l'ultrafiltration sur une membrane de seuil de coupure de 5 kDa peut être utilisée malgré une rétention incomplète (95-97 %). Par contre, la nanofiltration offre une rétention totale des anthocyanes. Le procédé, mis en uvre dans des conditions semi-industrielles, a permis d'augmenter la teneur en extrait sec soluble (ESS) de 40 à 250 g.kg-1 à 35 °C, à une pression transmembranaire comprise entre 20 et 30 bar avec un flux moyen de 15 kg.h-1.m-2. L'évaporation osmotique, testée sur un pilote équipé d'une membrane en polypropylène de 10 m2, a permis de concentrer l'extrait anthocyanique jusqu'à 620 g d'ESS.kg-1. Cet extrait concentré conserve toutes les qualités physico-chimiques, biochimiques, nutritionnelles et aromatiques de l'extrait initial. Le flux évaporatoire est directement corrélé à la teneur en extrait sec solub le du produit à concentrer. Enfin, divers couplages d'opérations unitaires ont été comparés pour obtenir un extrait concentré à partir de calices d'H. sabdariffa. Le procédé qui associe une extraction à froid, une pré-concentration par nanofiltration et une concentration par évaporation osmotique est la meilleure voie tant en terme de coûts d'investissement et de fonctionnement que de qualité de l'extraitHibiscus sabdariffa L. is a herbaceous plant, cultivated largely in tropical and subtropical areas of both hemispheres. In Senegal, where it was introduced in the 19th century, H. sabdariffa L. also called bissap or roselle is grown throughout the territory and operated primarily for its calyx. A refreshing drink is traditionally made from dried calyx by water extraction. The physical-chemical and biochemical characterization of the calyx allowed us to assess better the potential of this product. Thus, the calyx contained between 767 and 1480 mg.100g-1 of anthocyanins and between 1347 and 3736 mg.100g-1 of total polyphenols. They have an antioxidant capacity closed to 260 μmolTrolox.g-1. Malic acid is the major organic acid with content up to 2.3 g.100g-1. Because of these characteristics, the aqueous extract of H. sabdariffa calyx is an excellent source of anthocyanins. The work was then focused on the process for obtaining this extract. The study of solid-liquid extraction was performed from dried calyx with water at temperature range from 25 and 90 ° C. A maximum extraction yield of anthocyanin of 88 % was obtained at 25 ° C with a solid-to-solvent ratio of 1/25. Reducing the particle size and increasing the temperature decreased the extraction time but do not affect the extraction efficiency. A model of solid-liquid extraction which included the thermal anthocyanins degradation kinetics has been proposed and validated. Crossflow microfiltration with tubular ceramic 0.2 pore size membrane has produced a cold sterilized extract, stable during 90 days at 20 °C. We have shown here that the transmembrane pressure optimized at a volume reduction ratio (VRR) equal to 1 is no longer optimum when the VRR is increasing. To concentrate the anthocyanins present in the extract, the ultrafiltration membrane with a cutoff of 5 kDa can be used despite incomplete retention (95-97%). By cons, nanofiltration offers a tot al retention of anthocyanins. The method, implemented in semi-industrial conditions, has increased the content of total soluble solids (TSS) from 40 to 250 g.kg-1 at 35 °C at a transmembrane pressure between 20 and 30 bar with an average flow of 15 kg.h-1.m-2. The osmotic evaporation, tested on a pilot equipped with a polypropylene membrane of 10 m2, has concentrated anthocyanin extract up to 620 g TSS. kg-1. This concentrated extract retains all the physical-chemical, biochemical, nutritional and aromatic quality of the original extract. The evaporation flux is directly correlated with the total soluble solids content of the product to concentrate. Finally, various couplings of unit operations were compared to obtain a concentrated extract from H. sabdariffa calyx. The process which combines a cold extraction, a pre-concentration by nanofiltration and concentration by osmotic evaporation is the best way both in terms of investment costs and operating and quality of the ext ract
Books on the topic "Hibiscus sabdariffa"
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Francisco de Jesús Caro Velarde, María Luisa Machuca Sánchez, Ericka Patricia Flores Berrios, and Francisco de Jesús Caro Velarde. El cultivo de jamaica en Nayarit: (Hibiscus sabdariffa L.). Tepic, Nayarit: Universidad Autónoma de Nayarit, 2012.
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Roselle (Hibiscus sabdariffa). Elsevier, 2021. http://dx.doi.org/10.1016/c2019-0-04589-x.
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Padilla, Luis, Kamyre Neyra, Vladimir Huacasi, and Sonia Macedo. Efecto antibacterial in vitro del extracto etanolico de Hibiscus sabdariffa L. sobre cepas de Streptococcus mutans. Instituto Universitario de Innovación Ciencia y Tecnología Inudi Perú, 2022. http://dx.doi.org/10.35622/inudi.b.012.
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La caries dental es una de las enfermedades más frecuentes a nivel mundial y debido a su prevalecía se comenzó a utilizar la fitoterapia como tratamiento alternativo, la Hibiscus sabdariffa L. posee gran variedad de propiedades terapéuticas de las cuales en este estudio destaca su actividad antibacterial. Objetivo: El objetivo de esta investigación fue determinar el efecto antibacterial in vitro del extracto etanólico de Hibiscus sabdariffa L. sobre cepas de Streptococcus mutans a las 24 y 48 horas. Materiales y métodos: La investigación fue aplicativa de diseño experimental y medición prospectiva. La muestra fue obtenida de pacientes que firmaron el consentimiento informado para así poder obtener las cepas de Streptococcus mutans. Se cultivaron en 16 placas Petri y en cada placa se distribuyeron 7 discos de papel filtro N°4, la técnica fue de difusión por disco de Kirby Bauer con pozos, con un total de 112 discos y pozos; las placas Petri se dividieron en 4 grupos de acuerdo a las concentraciones del extracto etanólico de Hibiscus sabdariffa L. que se obtuvo por maceración con alcohol al 96% para obtener una muestra al 100% extracto etanólico de Hibiscus sabdariffa L. y para obtener las concentraciones de 25%, 50% y 75% se utilizó alcohol para realizar las diluciones. Se consideró la clorhexidina al 0.12% como control positivo y al agua destilada como control negativo. Resultados: Sé demostró que la Hibiscus sabdariffa L. tiene efecto inhibitorio. El mejor efecto se registró a las 48 horas al 100% de concentración. Obteniendo un halo de inhibición de 14.23mm. Conclusión: El extracto etanólico de la Hibiscus sabdariffa L. sí tiene efecto antibacterial in vitro sobre las cepas de Streptococcus mutans.
Book chapters on the topic "Hibiscus sabdariffa"
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Ross, Ivan A. "Hibiscus sabdariffa." In Medicinal Plants of the World, 267–75. Totowa, NJ: Humana Press, 2003. http://dx.doi.org/10.1007/978-1-59259-365-1_13.
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Lim, T. K. "Hibiscus sabdariffa." In Edible Medicinal and Non Medicinal Plants, 324–70. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-017-8748-2_23.
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Bährle-Rapp, Marina. "Hibiscus sabdariffa." In Springer Lexikon Kosmetik und Körperpflege, 257. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_4746.
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Khare, C. P. "Hibiscus sabdariffa Linn." In Indian Medicinal Plants, 1. New York, NY: Springer New York, 2007. http://dx.doi.org/10.1007/978-0-387-70638-2_749.
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Azimova, Shakhnoza S., and Anna I. Glushenkova. "Hibiscus sabdariffa L." In Lipids, Lipophilic Components and Essential Oils from Plant Sources, 624. London: Springer London, 2012. http://dx.doi.org/10.1007/978-0-85729-323-7_2030.
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Sastry, K. Subramanya, Bikash Mandal, John Hammond, S. W. Scott, and R. W. Briddon. "Hibiscus sabdariffa (Roselle) (Mesta)." In Encyclopedia of Plant Viruses and Viroids, 1167–68. New Delhi: Springer India, 2019. http://dx.doi.org/10.1007/978-81-322-3912-3_456.
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Mojica, Luis, Li Rui, and Elvira Gonzalez de Mejia. "Hibiscus sabdariffa L.: Phytochemical Composition and Nutraceutical Properties." In ACS Symposium Series, 279–305. Washington, DC: American Chemical Society, 2012. http://dx.doi.org/10.1021/bk-2012-1109.ch017.
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Villani, Tom, H. Rodolfo Juliani, James E. Simon, and Qing-Li Wu. "Hibiscus sabdariffa: Phytochemistry, Quality Control, and Health Properties." In ACS Symposium Series, 209–30. Washington, DC: American Chemical Society, 2013. http://dx.doi.org/10.1021/bk-2013-1127.ch014.
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González-Stuart, Armando. "Multifaceted Therapeutic Value of Roselle (Hibiscus sabdariffa L. – Malvaceae)." In Nutrients, Dietary Supplements, and Nutriceuticals, 215–26. Totowa, NJ: Humana Press, 2010. http://dx.doi.org/10.1007/978-1-60761-308-4_14.
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Taşdemir, Munir, Çiğdem Gül, and Emine Dilara Kocak. "Use of Roselle (Hibiscus sabdariffa) in Composite Materials for Sustainability." In Sustainable Textiles: Production, Processing, Manufacturing & Chemistry, 97–115. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-38013-7_5.
Full textConference papers on the topic "Hibiscus sabdariffa"
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Gois, Camila Maria Dassie, Clara Beatriz de Lima, Daniela Cristina de Medeiros Araújo, and Jacqueline Godinho. "Avaliação da atividade antioxidante do extrato de Hibiscus sabdariffa in vitro." In II Congresso Internacional Interdisciplinar da Uningá. Editora Uningá, 2023. http://dx.doi.org/10.46311/ed.un.20221018116.
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Diversas patologias estão associadas ao estresse oxidativo, assim, é crescente o interesse em substâncias antioxidantes, encontradas em plantas. Dentre as mesmas, destaca-se o Hibiscus sabdariffa, conhecido como hibisco, que apresenta substâncias como flavonoides e antocianinas, sendo estas promissoras no desenvolvimento de fármacos e cosmecêuticos. Assim, este estudo avaliou a atividade antioxidante do extrato hidroalcoólico de H. sabdariffa. Foi utilizado o método DPPH (2, 2 Defenil-1- pichilhidrazila) em microplacas. O H. sabdariffa apresentou IC50= 255,9 mcg/mL, exercendo a capacidade de reduzir 50% do radical livre de DPPH. Assim, conclui-se que o extrato hidroalcoólico de H. sabdariffa apresentou boa atividade antioxidante.
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"Tıbbi Bitki Hibiskus (Hibiscus sabdariffa L.)’un İn Vitro Çoğaltımı: Derleme." In PROCEEDING BOOK OF 1ST INTERNATIONAL CONFERENCE ON MODERN AND ADVANCED RESEARCH ICMAR 2023. All Sciences Academy, 2023. http://dx.doi.org/10.59287/icmar.1302.
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Yani, Nadia Falihah Ahmad, Nurhazwani Ismail, and Kai Siang Oh. "Potential of using Hibiscus Sabdariffa in treating greywater." In PROCEEDINGS OF THE INTERNATIONAL ENGINEERING RESEARCH CONFERENCE - 12TH EURECA 2019. AIP Publishing, 2019. http://dx.doi.org/10.1063/1.5120993.
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Rithichai, P., Y. Jirakiattikul, C. Sriboonthai, and A. Itharat. "Bioactive Compounds and Antioxidant in Hibiscus sabdariffa Leaf." In GA 2017 – Book of Abstracts. Georg Thieme Verlag KG, 2017. http://dx.doi.org/10.1055/s-0037-1608056.
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Vinícius Falci and Caroline Maria Calliari. "Elaboração e caracterização de licor de Hibiscus sabdariffa." In XX Seminário de Iniciação Científica e Tecnológica da UTFPR. Curitiba, PR, Brasil: Universidade Tecnológica Federal do Paraná - UTFPR, 2015. http://dx.doi.org/10.20906/cps/sicite2015-0459.
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Trejo-Durán, M., E. Alvarado-Méndez, J. A. Andrade-Lucio, R. Rojas-Laguna, and M. A. Vázquez-Guevara. "Study of large nonlinear change phase in Hibiscus Sabdariffa." In SPIE Organic Photonics + Electronics, edited by Jon A. Schuller. SPIE, 2015. http://dx.doi.org/10.1117/12.2187562.
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"Moisture Dependent Aerodynamic Properties of Roselle Calyxes (Hibiscus Sabdariffa)." In 2015 NABEC Northeast Agr Bio Eng Conference. American Society of Agricultural and Biological Engineers, 2015. http://dx.doi.org/10.13031/nabec2015-042.
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Güler, Nilgün. "Staining effect of Hibiscus sabdariffa extract on Human Blood Cells." In 15th International Congress of Histochemistry and Cytochemistry. Istanbul: LookUs Scientific, 2017. http://dx.doi.org/10.5505/2017ichc.pp-71.
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