ABSTRACT
Objective: To investigate the adsorption performance and purification effect of macroporous adsorption resin on total polyphenols in Acanthopanan trifoliates leaves, and to determine the technological conditions for the purification of total polyphenols from A. trifoliates leaves. Methods: The Folin-Ciocalteu colorimetric method was used to quantify the adsorption and desorption effects of five macroporous adsorption resins on the total polyphenols in the A. trifoliates leaves. The resin suitable for separation and purification of total polyphenols in A. trifoliates leaves was screened, and the adsorption and desorption conditions were investigated and optimized. The final optimized parameters were determined by single factor experiments. Results: The best purification parameters of total polyphenols were determined as follows: the concentration of sample solution was 1.0 mg/mL (crude drug) with pH 3.0, sample flow rate was at 2 mL/min, and the sample loading was controlled to 30 mL, the elution was 50% ethanol at a flow rate of 2.0 mL/min with pH 6.0, and the elution amount was 40 mL. The polyphenol sample of the A. trifoliates leaves was purified by HPD100 resin, and the purity increased from 11.7% to 49.7%, and the purification effect was 4.25 times than before. After 30 times enlargement experiment, the purity of the A. trifoliates leaves polyphenol sample increased from 12.5% before purification to 54.5%, and the purification effect was 4.4 times than before. The amount of macroporous resin did not affect the purification efficiency, which provided reference for HPD100 macroporous resin for industrial production of total polyphenols purification of A. trifoliates leaves. Conclusion: HPD100 is the best resin for purifying total polyphenols from A. trifoliates leaves, and the process technology result in this experiment can be applied to industrial production.
ABSTRACT
SUMMARY As a potential beverage, coffee leaf tea may possess both qualities of brewed coffee and regular tea. Thus, making it an attractive beverage in years to come. One of the main qualities is the leaf's phenolic content, which is chiefly attributed with health benefits. However, the leaf's total phenolic content may be adversely affected by heat during the drying process. Coffee leaves were dried using a combined drying process, high-temperature short-time (HTST) and convective drying, to assess the optimal drying parameters for both total phenolic content preservation and drying time reduction. To reach conclusions, a central composite rotational design (CCRD) was employed. With both temperature and thickness as independent variables, a response surface using time as dependent variable was generated. The temperature ranged from 80°C to 110°C and the thickness from 1cm to 3cm. Results indicate that the HTST pretreatment significantly reduced the drying time without affecting the total phenolic content; that is, the CCRD analysis on the effect of the HTST pretreatment on the total phenolic content did not yield statistically significant results.
RESUMEN Como bebida potencial, el té de hojas de café posee cualidades, tanto de café preparado como de té regular, por lo tanto, será una bebida interesante en los próximos años. Una de las principales cualidades es el contenido fenólico de las hojas, a lo cual, se atribuyen beneficios sobre la salud; sin embargo, el contenido fenólico total (TPC), se puede ver afectado negativamente por el calor, durante el proceso de secado. Hojas de café fueron secadas usando un proceso de secado combinado, tiempo corto y alta temperatura (HTST) y secado convectivo, para establecer los parámetros óptimos de secado, tanto para la preservación del TPC como para la reducción del tiempo de secado. Para obtener conclusiones, un diseño de experimentos rotacional central compuesto (CCRD) fue aplicado. Usando como variables independientes la temperatura y el espesor, se generó una superficie de respuesta, empleando el tiempo, como variable dependiente. El rango de temperatura usado fue entre 80 y 110 y de espesor, entre 1 y 3cm. Los resultados indican que el pretratamiento de HTST redujo significativamente el tiempo de secado, sin afectar el TPC, es decir, el análisis del CCRD sobre el efecto del pretratamiento del HTST en el TPC no obtuvo resultados estadísticamente significativos.
ABSTRACT
ABSTRACT Due to their nutraceutical properties, the fruits of the species Vaccinium meridionale, which inhabit the Andean region, are of scientific interest. Microwave-assisted extraction has been applied to different vegetal matrices for to extract efficiently polyphenolic compounds. In this work we study in microwave assisted extraction processes, the effect on the extraction of total polyphenols in dried fruits of Vaccinium meridionale, using response surface methodology. The main objective of this research was to analyze the relationships between power, temperature, solid-liquid ratio, time and ethanol concentration in aqueous media on the effectiveness of total polyphenols recovery in dry fruits of Vaccinium meridionale. A central composite design face-centered with three levels for each variable was used: P = 300 - 900 W; T = 70 -110 °C; L:Srat. = 30:1 - 70:1 w/w; t = 5 - 15 min; [EtOH] = 0 - 80%. In this sense, the effect of the input variables on the recovery of total polyphenols, the optimization process for maximum extraction, and the comparison to other solid-liquid extractions in terms of quantity of total polyphenols, are reported. It was found that the significant variables in the extraction process were ethanol concentration, temperature and time; the best yields were obtained in the range [EtOH] = 44 - 49%, T = 110 °C, and t = 10 - 15 min. In terms of quantity, time and consumption of energy, microwave-assisted extraction technique is more efficient than other solid-liquid extraction processes for the extraction of total polyphenols.
RESUMO Devido a suas propriedades nutracêuticas em termos do conteúdo de polifenóis totais, os frutos da espécie andina Vaccinium meridionale tem associado um grande interesse cientifico. A extração assistida por microondas tem sido utilizada em diferentes matrizes vegetais para a remoção de forma eficiente de compostos polifenólicos que apresentam uma atividade biológica. Neste artigo são apresentados os principais resultados experimentais obtidos em diferentes processos de extração assistida por microondas, com respeito à quantia de polifenóis totais removidos em frutos secos de Vaccinium meridionale por meio da metodologia da superfície de resposta. O principal objetivo desta pesquisa foi analisar as relações entre as variáveis independentes da potência, a temperatura, a relação sólido-líquido, tempo e concentração de etanol com respeito à quantidade polifenóis totais extraídos de frutos secos de Vaccinium meridionale. Foi utilizado um desenho composto centrado nas caras com três diferentes níveis para cada variável: P = 300 - 900 W; T = 70 -110 °C; L:Srat. = 30:1 - 70:1 w/w; t = 5 - 15 min; [EtOH] = 0 - 80%. Foi utilizado o método de Folin-Ciocalteu para a quantificação de polifenóis totais com ácido gálico como molécula de referência. Neste sentido, foi reportado neste trabalho o efeito dos fatores de entrada com respeito a quantidade de polifenóis totais removidos, o processo de optimização para obter a máxima remoção possível, e também uma comparação dos resultados experimentais com outros processos de extração sólido-líquido. Foi achado que a concentração de etanol, a temperatura e o tempo foram a variáveis mais importantes no processo de extração. A máxima quantidade de recuperação achada neste trabalho foi obtida no intervalo [EtOH] = 44 - 49%, T = 110 °C e t = 10 - 15 min. Em termos de quantidade, tempo e gasto de energia, a extração assistida por microondas é uma técnica eficiente para a remoção de polifenóis totais em frutos secos de Vaccinium meridionale.
ABSTRACT
Objective:To establish the protein content determination method respectively by Folin-Ciocalteu method and Coomass-ie brilliant blue binding method for mannatide oral solution and compare the results. Methods:The limit of detection, linearity, accu-racy, repeatability, recovery and content of Folin-Ciocalteu method and Coomassie brilliant blue binding method were investigated. Re-sults:As for Folin-Ciocalteu method, the limit of detection was 0. 2 μg, the range of linearity was 0-112. 0 μg(r=0. 9990), the av-erage recovery was 105. 2%(RSD=1. 9%), the RSD of accuracy was less than 1%, and the content result of three batches of samples was 47. 45, 58. 34 and 40. 99 μg·ml-1, respectively. As for Coomassie brilliant blue binding method, the limit of detection was 0. 8 μg, the range of linearity was 0-99. 6 μg(r=0. 9980), the average recovery was 102. 0%(RSD=2. 7%), the RSD of accuracy was less than 1%, and the protein content of samples was not detected out by the method. Conclusion:Folin-Ciocalteu method can be used to determine the protein content in mannatide oral solution reliably and efficiently.
ABSTRACT
Objective:To establish the protein content determination method respectively by Folin-Ciocalteu method and Coomass-ie brilliant blue binding method for mannatide oral solution and compare the results. Methods:The limit of detection, linearity, accu-racy, repeatability, recovery and content of Folin-Ciocalteu method and Coomassie brilliant blue binding method were investigated. Re-sults:As for Folin-Ciocalteu method, the limit of detection was 0. 2 μg, the range of linearity was 0-112. 0 μg(r=0. 9990), the av-erage recovery was 105. 2%(RSD=1. 9%), the RSD of accuracy was less than 1%, and the content result of three batches of samples was 47. 45, 58. 34 and 40. 99 μg·ml-1, respectively. As for Coomassie brilliant blue binding method, the limit of detection was 0. 8 μg, the range of linearity was 0-99. 6 μg(r=0. 9980), the average recovery was 102. 0%(RSD=2. 7%), the RSD of accuracy was less than 1%, and the protein content of samples was not detected out by the method. Conclusion:Folin-Ciocalteu method can be used to determine the protein content in mannatide oral solution reliably and efficiently.
ABSTRACT
En este trabajo se muestra el desarrollo y la validación de un método analítico para la cuantificación de polifenoles totales con el reactivo de Folin-Ciocalteu (F-C),en procesos de extracción asistida por microondas (MAE), sobre frutos de la especie colombiana Vaccinium meridionale. Los resultados obtenidos en los parámetros selectividad, linealidad, repetibilidad y exactitud muestran que la metodología propuesta es confiable para evaluar el efecto de las condiciones de extracción sobre la cantidad de polifenoles removidos.
In this work, we show the development and validation of an analytical method for quantification of total polyphenols with Folin-Ciocalteu reagent (F-C) in microwave-assisted extraction processes for Colombian species Vaccinium meridionale. Experimental results of selectivity, linearity, repeatability and accuracy evidence that the methodology proposed is reliable to evaluate the effect of the extraction conditions over the quantity of polyphenols removed.
ABSTRACT
In this work, the possible correlation between the antioxidant activities and the Total Phenolic Content (TPC) and chemical composition of Lamiaceae (H. conferta, H. dilatata, H. mutabilis, H. suaveolens), Burseraceae (P. heptaphyllum, T. rhoifoila, T. panamensis), and Lauraceae (Ocotea sp.) were evaluated. The Trolox Equivalent Antioxidant Capacity or the Total Antioxidant Activity (TAA) was determined by using a colorimetric assay with the ABTS radical cation, Effective Concentration (EC50) was evaluated with the DPPH radical, and the TPC was established by the Folin-Ciocalteu method, for ethanolic extracts obtained by cold maceration and evaporation to dryness. Both the TAA and the EC50 were highly correlated with the TPC. The barks of T. rhoifolia and T. panamensis demonstrated the highest antioxidant capacities. The Burseraceae spp. exhibited the highest TPC, and the Lamiaceae (Hyptis spp.) demonstrated the lowest TPC.
Neste trabalho foi avaliada a possível correlação entre as atividades antioxidantes, o conteúdo de fenóis totais e a composição química de Lamiaceae (H. conferta, H. dilatata, H. mutabilis, H. suaveolens), Burseraceae (P. heptaphyllum, T. rhoifoila, T. panamensis), e Lauraceae (Ocotea sp.). Para os extratos de etanol obtidos por maceração em frio e evaporação até a secura, a Capacidade Antioxidante Equivalente ao Trolox ou à Atividade Antioxidante Total (AAT), foi determinada por meio de um ensaio colorimétrico com o cátion radical ABTS, a concentração eficaz (EC50) foi avaliada com o radical DPPH, e o Conteúdo de Fenóis Totais (CFT) foi estabelecido pelo método do Folin-Ciocalteu. Tanto a AAT quanto a EC50 estiveram altamente relacionadas com a CFT. A casca de T. rhoifolia e T. panamensis apresentaram as maiores capacidades antioxidantes. As Burseraceae spp. apresentaram o CFT mais alto, e as Lamiaceae (Hyptis spp.) apresentaram o CFT mais baixo.
En este trabajo se evaluó la posible correlación entre las actividades antioxidantes, el contenido de fenoles totales (CFT) y la composición química de Lamiaceae (H. conferta, H. dilatata, H. mutabilis, H. suaveolens), Burseraceae (P. heptaphyllum, T. rhoifoila, T. panamensis) y Lauraceae (Ocotea sp.). Para los extractos etanólicos obtenidos por maceración en frio y evaporación a sequedad, la Capacidad Antioxidante Equivalente al Trolox o la Actividad Antioxidante Total (AAT), fueron determinadas mediante un ensayo colorimétrico con el catión radical ABTS, la Concentración Efectiva (EC50) fue evaluada con el radical DPPH, y el Contenido de Fenoles Totales (CFT), fue establecido mediante el método de Folin-Ciocalteu. Tanto la AAT como la EC50 estuvieron altamente correlacionados con el CFT. Las cortezas de T. rhoifolia y T. panamensis mostraron las capacidades antioxidantes más altas. Las Burseraceae spp. mostraron los TPC más altos y las Lamiaceae (Hyptis spp.) mostraron los TPC más bajos.
ABSTRACT
Existem variedades de mandioca que apresentam compostos como os carotenoides, beta-caroteno, licopeno e minerais importantes para a saúde humana e animal. O presente estudo avaliou a atividade antioxidante das variedades branca, amarela e rosada de Manihot esculenta, por meio de teste de DPPH e pela atividade quelante de íons ferro. Além disso, o conteúdo de fenóis totais, carotenoides, beta-caroteno, licopeno e zinco também foram determinados. Utilizando o teste de DPPH foi possível verificar que os extratos de amostras cozidas apresentaram maior atividade antioxidante (89,53% - rosada) em comparação com as amostras frescas (1,97% - branca). Para o teste de atividade quelante de íons ferro, a maior atividade foi encontrada para o extrato da variedade rosada cozida (63,43%) e a menor foi do extrato da amarela in natura (17,34%) a amostra branca não apresentou atividade. A maior concentração de fenóis e de zinco foi obtida para o extrato da variedade rosada cozida 136,12 mg EAG/g de extrato e 0,811 ppm, respectivamente, na concentração de 1000 µg/mL. A variedade rosada apresentou também maior quantidade de pigmentos, incluindo carotenoides (29,40 µg/g); beta-caroteno (9,14 µg/100g) e licopeno (68,92%). De acordo com os resultados obtidos no presente estudo, foi possível concluir que as variedades amarela e rosada de M. esculenta, apresentam quantidades de compostos fenólicos e minerais suficientes para atribuir a atividade antioxidante, podendo assim, contribuir para diminuir os danos oxidativos e serem utilizadas como nutracêuticos ou diretamente ingeridas na dieta para manter a boa saúde.
There are cassava varieties that present compounds as carotenoids, beta-carotene, lycopene and minerals important for human and animal health. The present study evaluated the antioxidant activity of the white, yellow and pinkish varieties of Manihot esculenta, by mean of the DPPH test and by the ferrous ion-chelating activity. Furthermore, the total phenols, carotenoids, beta-carotene, lycopene and zinc contents were also determined. Utilizing the DPPH test it was possible to find that extracts of boiled samples presented higher antioxidant activity (89.53% - pinkish) in comparison to the fresh samples (1.97% - white). For the ferrous ion-chelating test, the highest activity was found for the boiled pinkish variety extract (63.43%) and the lowest was for fresh yellow extract (17.34%) the white sample did not present activity. The highest concentration of total phenols and zinc content was obtained for the boiled pinkish variety extract 136.12 mg EAG/g of extract and 0,811ppm, respectively, in the concentration of 1000 µg/mL. The pinkish variety presented also higher quantity of pigments, including carotenoid (29.40 µg/g), beta-carotene (9.14 µg/100g) and lycopene (68.92%). According to the results obtained in this study it was possible to conclude that the yellow and pinkish varieties of M. esculenta present quantity of phenolic compounds and minerals sufficient to attribute the antioxidant activity and may thus contribute to reduce oxidative damage and be used as nutraceuticals or directly ingested in the diet to maintain good health.
Subject(s)
Zinc , Carotenoids , Manihot , beta Carotene , Dietary SupplementsABSTRACT
Objective: To evaluate hydrophilic extracts from edible portions of fifteen plants for total phenolic content (TPC) and anti-oxidant capacity (AC) as an effort to find possible sources for future novel antioxidants. Methods: Folin-Ciocalteau and DPPH radical scavenging assays were employed to determine TPC and AC, respectively. Results: Among the assayed plants, TPC (mean±SD), expressed as gallic acid equivalent, varied from 0.04±0.01 (Amaranthus spinosus) to 6.01±0.04 (Zanthoxylum rhetsa) mg gallic acid equivalent/g fresh weight. AC (mean±SD), expressed as trolox equivalent, ranged from 0.14±0.00 (Alternanthera philoxeroides) to 7.54±0.00 (Zanthoxylum rhetsa) μmol trolox equivalent/g fresh weight. A significant and positive linear relationship (R
ABSTRACT
OBJECTIVE@#To evaluate hydrophilic extracts from edible portions of fifteen plants for total phenolic content (TPC) and anti-oxidant capacity (AC) as an effort to find possible sources for future novel antioxidants.@*METHODS@#Folin-Ciocalteau and DPPH radical scavenging assays were employed to determine TPC and AC, respectively.@*RESULTS@#Among the assayed plants, TPC (mean±SD), expressed as gallic acid equivalent, varied from 0.04±0.01 (Amaranthus spinosus) to 6.01±0.04 (Zanthoxylum rhetsa) mg gallic acid equivalent/g fresh weight. AC (mean±SD), expressed as trolox equivalent, ranged from 0.14±0.00 (Alternanthera philoxeroides) to 7.54±0.00 (Zanthoxylum rhetsa) μmol trolox equivalent/g fresh weight. A significant and positive linear relationship (R(2)=0.99) was observed between TPC and AC of Zanthoxylum rhetsa, Oxalis corymbosa, and Alternanthera sessilis.@*CONCLUSIONS@#The results of the present study implies that the analyzed plants possess varying degree of antioxidant capacity and, therefore, the antioxidant potency of these underused plants may be utilized to prevent oxidative damage and oxidative stress related disorders.
ABSTRACT
Objective To establish determination method for total polyphenols in Guhong Injection, and provide reference for internal quality control of Guhong Injection.[Methods]Using the Folin-Ciocalteu colorimetric method, according to the consistent degree of the maximum absorption wavelengths of hydroxysafflor yel ow A and kaempferol relative to Guhong Injection, we selected the appropriate reference and color reaction condition to content determination.[Rsults]With hydroxysafflor yel ow A as the standard, the content of total polyphenols in 10 batches of samples were 9.94, 9.55, 9.75, 9.67, 9.84, 10.03, 9.81, 9.52, 9.88, 10.09mg·mL-1. The average recovery of total polyphenols was 98.11% and RSD was 1.68%(n=6). [Conclusion]The established Folin-Ciocalteu method is simple, accurate, sensitive, and is reliable for detecting total polyphenols in Guhong Injection.
ABSTRACT
Introducción: la proliferación de radicales libres en el cuerpo humano induce daños oxidativos a las biomoléculas que provocan daños a nivel celular y generan diversas anomalías en el organismo, como arterosclerosis, envejecimiento y cáncer. Actualmente, la búsqueda por moléculas con características antioxidantes es cada vez mayor, donde las plantas representan una de las principales fuentes de compuestos. Objetivo: determinar la actividad antioxidante y el contenido de fenoles de los extractos de diferentes polaridades de la parte aérea de la especie Palicourea guianensis (Rubiaceae). Métodos: para la evaluación de la actividad biológica, se calcularon los valores de concentración media inhibitoria (IC50) de los extractos más activos mediante los métodos de captura de electrones DPPH (2,2-difenil-1-picrilhidracilo) y ABTS (ácido 2,2'azinobis-(3-etilbenzotiazolina)-6-sulfónico). Adicionalmente, se determinó la concentración de fenoles totales presentes en los extractos a través del método de Folin-Ciocalteu. Resultados: los extractos en acetato de etilo (PgAEF) y en agua (PgAF) presentaron mayor actividad antioxidante con valores de IC50 de 5 207 y 3 912 mg/L respectivamente. Asimismo, se observó una relación directamente proporcional entre la concentración de fenoles totales presentes en los extractos y la actividad antioxidante exhibida. Conclusiones: las especies de la familia Rubiaceae, especialmente P. guianensis, son una fuente promisoria e importante de metabolitos secundarios con capacidad antioxidante, por lo cual se requieren de mayores estudios que permitan identificar dichas sustancias e integrarlas a programas de terapia antioxidante en el área de la salud(AU)
Introduction: the proliferation of free radicals in the human body induces oxidative damage to biomolecules that cause damage at the cellular level and can generate various abnormalities in the body, such as atherosclerosis, aging and cancer. Currently, the search for molecules with antioxidant properties is increasing, where the plants are a major source of compounds. Objective: to determine the antioxidant activity and phenolic content of extracts of different polarities from the aerial part of Palicourea guianensis (Rubiaceae) species. Methods: for evaluation of the biological activity, the values of the mean inhibitory concentration (IC50) of the most active extracts were estimated by the methods of electron capture DPPH (2,2-diphenyl-1-picrylhidracyl) and ABTS (2,2'azinobis-(3-ethylbenzothiazoline)-6-sulfonic acid). Additionally, the total phenol concentration present in the extracts was determined using the Folin-Ciocalteu reagent. Results: the extracts in ethyl acetate (PgAEF) and in water (PgAF) showed higher antioxidant activity with IC50 values of 5 207 and 3 912 mg/L respectively. Furthermore, there was direct relationship between the concentration of total phenols present in the extracts and the antioxidant activity. Conclusions: Rubiaceae family species, especially P. guianensis are a promising and important source of secondary metabolites with antioxidant capacity, so further studies are required to identify these substances and integrate them to the antioxidant therapy programs of the health areas(AU)
Subject(s)
Rubiaceae/drug effects , Antioxidants/therapeutic use , ColombiaABSTRACT
In this study we evaluated the antioxidant and antihyperglycemic activity in vitro of the extracts obtained with solvents: hexane, ethyl acetate and methanol, of the medicinal plant Oreocallis grandiflora (cucharillo), collected in the Saraguro indian community of the province Loja, southern Ecuador. The antioxidant activity was evaluated by the tests: DPPH, FOLIN-CIOCALTEU and beta-CLAMS, while the antihyperglycemic activity was determined by inhibition assay á-amylase and alpha-glucosidase. The samples were diluted to different concentrations and the reading was performed in a UV spectrophotometer, using as positive control á-tocopherol for DPPH and Folin-ciocalteu test, trolox for beta-CLAMS test, and Glucobay® for testing alpha-amylase and alpha-glucosidase.The results are expressed as IC50, these show that the methanol extract of Oreocallis grandiflora has inhibitory effect on alpha-amylase, the IC50 is 109 ug/ml, compared to 126 ug/ ml of Glucobay®. It also shows inhibitory effect on á-glucosidase, the IC50 is 3 ug/ml compared to 1316 ug/ml of Glucobay®. It also shows antioxidant activity, its IC50 is 15 ug/ml compared to 5 ug/ml of á-tocopherol.
En el presente trabajo se evaluó la actividad antioxidante y antihiperglucemiante in vitro de los extractos obtenidos con los solventes: hexano, acetato de etilo y metanol, de la planta medicinal Oreocallis grandiflora (cucharillo), recolectada en la comunidad indígena de Saraguro en la provincia de Loja, al sur del Ecuador. La actividad antioxidante fue evaluada a través de los ensayos: DPPH, FOLIN-CIOCALTEU y beta-CLAMS, mientras que la actividad antihiperglucemiante fue determinada por el ensayo de inhibición de alfa- amilasa y alfa-glucosidasa. El extracto metanólico de Oreocallis grandiflora presenta efecto inhibitorio sobre la enzima alfa-amilasa, su concentración inhibitoria (CI50) es de 109 ug/ml, frente a 126 ug/ml del control positivo Glucobay®. Además, muestra efecto inhibitorio sobre la enzima alfa-glucosidasa, su concentración inhibitoria (CI50) es de 3 ug/ml, frente a 1316 ug/ml del Glucobay®. Muestra también actividad antioxidante, su concentración inhibitoria (CI50) es de 15 ug/ml, frente a 5 ug/ml del alfa-tocoferol.
Subject(s)
Antioxidants/pharmacology , Plant Extracts/pharmacology , Hypoglycemic Agents/pharmacology , Proteaceae/chemistry , Biphenyl Compounds , Ecuador , Phenols/analysis , Picrates , Plants, Medicinal , alpha-Amylases/antagonists & inhibitors , alpha-Glucosidases/antagonists & inhibitorsABSTRACT
Objective: To evaluate the total phenolic, flavonoid contents and in vitro antioxidant activity of methanol extract of Dioscorea esculenta (Lour). Burkill. Methods: Total phenolic content was estimated using the Folin Ciocalteu method. The flavonoid content was determined using aluminium chloride. In vitro antioxidant activities and reducing power capacity were determined using standard methods. Results: Total phenolic content in methanol extract of Dioscorea esculenta was found to be 0.79g/100g and flavonoids content was found to be 0.26 g/100g. The extract was screened for its potential antioxidant activities using tests such as DPPH radical scavenging activity, hydroxyl radical scavenging activity, superoxide radical scavenging activity, ABTS radical cation scavenging activity and reducing power activity. Conclusions: The present studies confirm the methanol extracts have potential in vitro antioxidant activity. The phytochemical phenols and flavonoids could be the reason for its antioxidant activity.
ABSTRACT
Objective: To evaluate the total phenolic, flavonoid contents and in vitro antioxidant activity of methanol extract of Xanthosoma sagittifolium corm. Methods: Total phenolic content was estimated using the Folin Ciocalteu method. The flavonoid content was determined using aluminium chloride. In vitro antioxidant activities were evaluated by studying DPPH radical scavenging activity, hydroxyl radical scavenging activity, superoxide radical scavenging activity, ABTS radical cation scavenging activity and reducing power capacity were determined using standard procedure. Results:Xanthosoma sagittifolium corm exhibited 0.32g100g-1 total phenolic; 0.26g100g-1 flavonoid and better scavenging activity of DPPH (78.22±0.56%), hydroxyl radical (69.11±0.21%), superoxide radical (83.27±0.08%) and ABTS radical cations(76.11±0.07%).Conclusions: The present studies confirm the methanol extracts have potential in vitro antioxidant activity.
ABSTRACT
Because of the increasing interest in improving human health worldwide, phytochemical antioxidants from medicinal and food plants are of great interest. The search for new sources of antioxidants is important for the best use of biodiversity. The objective of this work was to evaluate the antioxidant activity and the total phenolic compounds with DPPH and Folin-Ciocalteu assays for extracts and fractions of Blechnum chilense, Curcuma domestica and Tagetes verticillata. B. chilense water-methanolic and EtOAc fractions, follows of C. domestica EtOAc extract showed an important quantity of total phenolic compounds. Compared with Aristotelia chilensis MeOH extract, T. verticillata extract showed good activity, follows by EtOAc fraction from B. chilense and by EtOAc extract from C. domestica, with very similar results with n-hexane fraction from B. chilense and petroleum ether extract from C. domestica. All of these results were greater than alpha-tocopherol DPPH scavenging activity. The results suggest that all plants studied could be are new sources of antioxidants and the work are following with the identification of these compounds.
Debido al creciente interés mundial en el mejoramiento de la salud humana los antioxidantes provenientes de plantas medicinales y alimenticias se han convertido en compuestos de gran interés. La búsqueda de nuevas fuentes de antioxidantes es importante para el mejor uso de la biodiversidad. El objetivo de este trabajo fue evaluar la actividad antioxidante y el contenido de fenoles totales usando el método de Folin-Ciocalteu y la actividad inhibitoria del radical DPPH de fracciones y extractos de Blechnum chilense (Kaulf.) Mett, Curcuma domestica Valeton y Tagetes verticillata Lag. & Rodr. Las fracciones acuosa-metanólica y EtOAc de B. chilense, seguida del extracto EtOAc de C. domestica, mostraron una cantidad importante de compuestos fenólicos. La prueba con DPPH mostró que la actividad secuestrante más importante, comparada con la del extracto metanólico de Aristotelia chilensis (Molina) Stuntz, fue la del extracto de T. verticillata, seguido de la fracción EtOAc de B. chilense y el extracto EtOAc de C. domestica, con resultados similares a la fracción hexánica de B. chilense y el extracto obtenido con éter de petróleo de C. domestica, superando todas la actividad secuestrante de DPPH del alfa-tocoferol. Los resultados sugieren que todas las plantas estudiadas podrían ser nuevas fuentes de antioxidantes y se está trabajando para la identificación de los compuestos responsables de la actividad.
Subject(s)
Antioxidants/pharmacology , Curcuma/chemistry , Plant Extracts/pharmacology , Phenols/analysis , Ferns/chemistry , Tagetes/chemistry , Chile , Free Radical ScavengersABSTRACT
This study was aimed at assessing the antioxidant capacity and phenolic (free, bound, and total) contents in selected commercial beverages. Three different types of beverages commonly available in Malaysian supermarkets namely, cocoa, coffee and tea were selected. Phenolic contents were determined using a Folin-Ciocalteu assay. Antioxidant capacity (ferric reducing power and scavenging activity) was determined using FRAP and TEAC assays. Based on analysis of variance, coffee showed the highest amount of free phenolic compounds and antioxidant capacity compared to cocoa and tea (p < 0.05). The major phenolic compound detected in coffee was chlorogenic acid. Cocoa showed higher phenolic content than tea. However, cocoa and tea have similar catechin content and possessed comparable antioxidant capacity. The free phenolic content in the three beverages was found to be highly correlated with antioxidant capacity. In addition, moderate correlation was observed between total phenolic content and antioxidant capacity. On the other hand, there was no significant contribution of bound phenolic compounds towards antioxidant capacity. The contribution of antioxidant capacity in these beverages could be due to phenolic compounds in the free form. The study indicated that the beverages studied possessed varying degrees of antioxidant capacity and phenolic contents.