ABSTRACT
Roselle (Hibiscus sabdariffaL.) is natural source of valuable components such as phenolics, flavonoids and anthocyanins. Anthocyaninis normally used in the food technology to replace synthetic pigments as well as medicinal properties due to antioxidants. Microwave irradiation is a feasible green solvent extraction method receiving great attention as it utilizes solvent at elevated temperature and controlled pressure conditions. Microwave extraction emerges as a promising inexpensive, simple and efficient technique. In our research, various variable like microwave power (20, 40, 60, 80, 100 W), microwave frequency (10, 20, 30, 40, 50 GHz), the micrwave irradiation duration (5, 10, 15, 20, 25 min), liquid to solid ratio (water: material, 2:1, 3:1, 4:1, 5:1, 6:1), extraction temperature (50, 55, 60, 65, 70C), number of extraction cycles (1, 2, 3, 4, 5) influencing to the microwave-assisted extraction of phytochemicals in roselle (Hibiscus sabdariffa L.)calyx were thoroughly examined. Total total phenolic (mg GAE/ 100g), total flavonoid (mg GE/ 100g), anthocyanin (mg/100g) were key indicators to define the optimal variable. Our resultsrevealed that microwave power at 80 W, frequency 40 GHz, duration 15 min, liquid to solid ratio 4:1, temperature 55C, 4 cycles of extraction were appropriate for extraction of phytochemical components inside roselle (Hibiscus sabdariffa L.)calyx
ABSTRACT
Background: Hibiscus sabdariffa L. or Roselle, is one of the most common flower plants cultivated worldwide. Traditionally, it is claimed to reduce weight and cholesterol level. The aim of this study was to evaluate the effects of anthocyanin-rich Roselle aqueous extract on the physical, biochemical and histological changes in obese-hypercholesterolaemic rat model.Methods: Thirty Sprague-Dawley male rats were divided into five groups (n=6 per group). Group 1 is normal control (NC) rat that was fed with normal diet. The remaining rats (Group 2-5) were fed with commercial high-fat diet (HFD) for 6 weeks to induce obese-hypercholesterolaemic (OH) rat. After induction, the OH rats were divided into 4 groups: OH-Untreated group, OH-ARTE; OH treated with 300 mg/kg Roselle aqueous (anthocyanin-rich) and 1% trifluoroacetic acid extract (ARTE), OH-Orlistat; OH treated with 37 mg/kg orlistat and OH-Atorvastatin; OH treated with 10 mg/kg atorvastatin. After the 3 weeks intervention period, all rats were sacrificed. Body mass index, lipid profile and liver enzymes were evaluated. The liver section was subjected to hematoxylin and eosin staining for histopathological evaluation.Results: This study showed that 3 weeks administration of ARTE significantly reduced BMI, improved levels of lipid profile and liver enzymes, and histopathological changes of liver when compared to OH-untreated rats. The results were also comparable to the standard drugs.Conclusions: This study suggested that Roselle extract constitutes an effective and safe alternate treatment for obesity and hyperlipidaemia.
ABSTRACT
RESUMEN El fácil acceso y preparación de bebidas a base de Hibiscus sabdariffa L. representa una alternativa en el tratamiento de enfermedades crónicas y degenerativas. El estudio tuvo como objetivo comparar la contracción de fenoles totales y flavonoides en cálices de Hibiscus sabdariffa L., de una marca comercial y otra sin permiso sanitario. Para la determinación de fenoles totales se utilizó el método de Folin-Ciocalteu y método colorimétrico de Marinova para flavonoides. Se encontró una diferencia estadísticamente significativa (p<0,05) en la concentración de fenoles totales y flavonoides. Estos resultados demuestran que existen factores que condicionan el contenido de compuestos fenólicos, flavonoides y otros compuestos bioactivos.
SUMMARY The easy access and preparation of drinks based on Hibiscus sabdariffa L. represents an alternative in the treatment of chronic and degenerative diseases. The objective of the study was to compare the contraction of total phenols and flavonoids in chalices of Hibiscus sabdariffa L., of one commercial brand and another without sanitary permission. For the determination of total phenols, the Folin-Ciocalteu method and the Marinova colorimetric method for flavonoids were used. A statistically significant difference (p<0.05) was found in the concentration of total phenols and flavonoids. These results show that there are factors that condition the content of phenolic compounds, flavonoids in chalices and other bioactive compounds.
ABSTRACT
Roselle (Hibiscus sabdariffa L.) family Malvaceae is an important crop used in food, cosmetics and pharmaceutics industries. Roselle is cultivated mainly in Upper Egypt (Qena and Aswan governorates) producing 94% of total production. Root rot disease of roselle is one of the most important diseases that attack both seedlings and adult plants causing serious losses in crop productivity and quality. The main objective of the present study is to identify and characterize pathogens associated with root rot and wilt symptoms of roselle in Qena, Upper Egypt and evaluate their pathogenicity under greenhouse and field condition. Fusarium oxysporum, Macrophomina phaseolina, Fusarium solani, Fusarium equiseti and Fusarium semitectum were isolated from the natural root rot diseases in roselle. All isolated fungi were morphologically characterized and varied in their pathogenic potentialities. They could attack roselle plants causing damping-off and root rot/wilt diseases in different pathogenicity tests. The highest pathogenicity was caused by F. oxysporum and M. phaseolina followed by F. solani. The least pathogenic fungi were F. equiseti followed by F. semitectum. It obviously noted that Baladi roselle cultivar was more susceptible to infection with all tested fungi than Sobhia 17 under greenhouse and field conditions. This is the first report of fungal pathogens causing root rot and vascular wilt in roselle in Upper Egypt.
Subject(s)
Adult , Humans , Efficiency , Egypt , Fungi , Fusarium , Malvaceae , Seedlings , VirulenceABSTRACT
O hibisco (Hibiscus sabdariffa L.) possui propriedades antioxidantes e antimicrobianas, e pode ser utilizado como planta medicinal e alimento funcional. Este estudo determinou a intensidade de atividade de inibição (IINIB) e a inativação bacteriana (IINAB) in vitro de dois extratos alcoólicos, obtidos de cálices e frutos com sementes de diferentes acessos de hibisco. As análises foram efetuadas sobre as bactérias de padrão internacional, Enterococcus faecalis, E. coli, Salmonella Enteritidis e S. aureus, associando-se os resultados aos polifenóis totais e antocianinas. Diferenças significativas na atividade antimicrobiana dos extratos alcoólicos foram observadas em ambos os acessos. Salmonella Enteritidis (11,5) e E. coli (12) foram as bactérias mais sensíveis, respectivamente, aos extratos alcoólicos de cálices de hibisco e dos frutos com sementes. S. aureus (5,2 e 0,1) foi a mais resistente a ambos os extratos. Os valores de IINIB foram predominantemente maiores quando comparados aos de IINAB, o que indica que geralmente a atividade bacteriostática é maior do que a bactericida. Os valores de polifenóis totais e de antocianinas do extrato alcoólico de cálices apresentaram diferença significativa e foram superiores aos do extrato alcoólico dos frutos com sementes. Possivelmente exista associação direta entre a concentração de antocianina e a atividade antibacteriana em diferentes estruturas vegetais do hibisco.
Subject(s)
Functional Food , Antioxidants , Anthocyanins , Plant Extracts , HibiscusABSTRACT
The hypolipidemic, antioxidative and hepatoprotective activities of 200 and 300mg/kg body weight ethanolic extract of dried flower of Hibiscus sabdariffa L. (HSE) were assessed in rats treated with 0.25ml/kg body weight (intraperitoneally) of carbon tetrachloride (CCl4). Hepatic malondialdehyde (MDA), serum lipid profile, serum vitamins A, C and β- carotene, alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase (ALP) activities were measured. The oral administration of the extracts showed a significant (P<0.05) dose-dependent decrease in the CCl4- induced MDA formation in liver. Also HSE pretreatment, showed a significant increase in HDL-C concentration and decrease in the levels of total cholesterol, LDL-C and TG as compared to control. The levels of vitamins A, C, and β- carotene were shown to be significantly (P<0.05) decreased and increased respectively in CCl4 and HSE treated groups when compared with the control. The increase in the levels of these vitamins might not be unconnected with the antioxidant properties possessed by the extract. The extract also displayed a strong hepatoprotective effect as it significantly reduced CCl4- induced hepatotoxicity in rats, as judged from the serum activities of ALT, AST, and ALP. These results suggest that the ethanolic extract of dried flower of Hibiscus sabdariffa L. possesses antioxidant, hepatoprotective and hypolipidemic effects on CCl4-induced oxidative stress in rats.
ABSTRACT
O objetivo deste trabalho foi avaliar os efeitos do espaçamento entre plantas na linha e da aplicação ou não de cama-de-frango em cobertura no solo, na atividade antioxidante, teor total de fenóis e flavonóides em extrato etanólico e extrato aquoso quente de folhas de rosela (Hibiscus sabdariffa L.). Os tratamentos consistiram de cinco espaçamentos entre plantas (0,30; 0,35; 0,40; 0,45 e 0,50m) e do uso ou não de cama-de-frango em cobertura do solo, na dose de 10t ha-1, arranjados como fatorial 5x2, no delineamento blocos casualizados, com quatro repetições. Os teores de flavonóides e fenóis totais aumentaram no extrato etanólico (18 por cento e 11 por cento, respectivamente) e no extrato aquoso quente (16 por cento e 11 por cento, respectivamente) entre a aplicação ou não de cama-de-frango em cobertura no solo. A atividade antioxidante foi influenciada significativamente pelo método de obtenção dos extratos, sendo no extrato etanólico 263 por cento maior que o resultado obtido para o extrato aquoso quente.
The purpose of this paper was to analyze the effects of plant spacing within rows by means of applying or not applying chicken-manure to the soil cover in the antioxidant activity, total phenolic and flavonoids in ethanolic leaves extract and hot aqueous extract of roselle. The treatments consisted of five different spaces between plants (0.30, 0.35, 0.40, 0.45 and 0.50m) and the use or non-use of chicken litter broadcasted on soil surface at 10 ton ha-1, in a 5x2 factorial arrangement in a randomized block design with four replications. The flavonoids levels and total phenolic increased on ethanolic leaves extract (18 percent and 11 percent, respectively) and hot aqueous extract (16 percent and 11 percent, respectively) between applying or not applying chicken-manure to the soil cover. Antioxidant activity was significantly influenced by the way of obtaining extracts, being the ethanolic extract 263 percent higher than the results obtained by the hot aqueous extract.