ABSTRACT
Objective: To investigate the antioxidant activity, total phenolic and total tannin content of the pericarp and the seed of Coffea benghalensis (C. benghalensis) and Coffea liberica compared to Coffea arabica (C. arabica). Methods: The antioxidant potential, total tannin and polyphenol contents of the immature and mature seed and pericarp of C. benghalensis and Coffea liberica were quantified and compared to C. arabica. Enhanced chemiluminescence (ECL), 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity, Folin-Ciocalteau method and total tannin content assays were used. Results: Trolox equivalent (TE/g plant material) values obtained by ECL and DPPH methods showed loose correlation (r
ABSTRACT
OBJECTIVE@#To investigate the antioxidant activity, total phenolic and total tannin content of the pericarp and the seed of Coffea benghalensis (C. benghalensis) and Coffea liberica compared to Coffea arabica (C. arabica).@*METHODS@#The antioxidant potential, total tannin and polyphenol contents of the immature and mature seed and pericarp of C. benghalensis and Coffea liberica were quantified and compared to C. arabica. Enhanced chemiluminescence (ECL), 2,2-diphenyl-1-picrylhydrazyl (DPPH), oxygen radical absorbance capacity, Folin-Ciocalteau method and total tannin content assays were used.@*RESULTS@#Trolox equivalent (TE/g plant material) values obtained by ECL and DPPH methods showed loose correlation (r(2) = 0.587) while those measured by oxygen radical absorbance capacity assay were higher without correlation in each plant. A closer correlation was detected between the ECL method and the percentage antioxidant activity of the DPPH technique (r(2) = 0.610 7) in each species, however the immature pericarp of C. benghalensis showed much higher DPPH scavenging potential than was seen in the ECL assay. The immature pericarp of C. benghalensis expressed the highest tannin and polyphenol content, and a high polyphenol level was also detected in the immature seed of C. arabica. The immature pericarp of Bengal and Liberian coffees showed the largest amount of phenolic contents.@*CONCLUSIONS@#The obtained data highlight the potential role of C. benghalensis as a new source of natural antioxidants and polyphenols compared to C. arabica.
ABSTRACT
Sarcanthus pauciflorus is a pendulous epiphytic orchid belonging to the family Orchidaceae. The present study was conducted to determine antimicrobial, antioxidant, anthelmintic and insecticidal efficacy of methanol extract of S. pauciflorus. Antimicrobial activity of methanol extract was determined against four bacteria and two fungi by Agar well diffusion method. Antioxidant activity was performed by DPPH free radical scavenging and Ferric reducing assay. Anthelmintic activity was studied on the basis of time taken for paralysis and death of adult Indian earthworms by the extract. Insecticidal activity, in terms of larvicidal effect, was evaluated using II instar larvae of Aedes aegypti. Total phenolic content of extract was estimated by Folin-Ciocalteau reagent assay. Phytoconstituents viz., tannins, saponins and glycosides were detected in methanol extract. Content of total phenolics was found to be 258.65 mg GAE/g of extract. All test bacteria and fungi were susceptible to extract of orchid. Bacillus subtilis and Cryptococcus neoformans were susceptible to high extent among bacteria and fungi respectively. Gram positive bacteria have shown greater susceptibility than Gram negative bacteria to extract. The extract exhibited marked dose dependent scavenging of DPPH free radicals. An increase in absorbance at 700nm revealed reducing power of the extract. The extract caused paralysis and death of adult Indian earthworms in a dose dependent manner. The lethal effect of extract on II instar larvae of Aedes aegypti was found to be dose dependent. The results of the present study shows that the methanol extract of S. pauciflorus is found to possess antimicrobial, antioxidant, anthelmintic and insecticidal activities which might be attributed to the presence of secondary metabolites. Further experimentations concerned with isolation of the bioactive components present in the orchid and determination of their biological activities are under progress.
ABSTRACT
O envelhecimento cutâneo está relacionado com a ação de radicais livres que, por consequência da senescência, acabam estando em maior quantidade e logo as defesas naturais não conseguem eliminá-los. O objetivo deste trabalho foi desenvolver uma emulsão não-iônica com adição do extrato aquoso das entrecascas de Lafoensia pacari A. St.-Hil. e avaliar sua estabilidade físico-química, assim como a atividade antioxidante. O extrato aquoso foi preparado sob refluxo na proporção 1:25. A dosagem de polifenóis totais se deu pelo método Folin-Ciocalteau, com ácido tânico como padrão. Foram incorporados à emulsão não-iônica BHT e ácido ascórbico, ambos empregados como substâncias de referência e o extrato aquoso na concentração de 1%. A análise da atividade antioxidante foi realizada pelo método do fosfomolibdênio, onde cada amostra foi diluída a concentração de 400 miug/mL. A incorporação de extrato aquoso de L. pacari não influenciou de maneira significativa na estabilidade do creme em relação ao tempo de análise. A quantificação de polifenóis mostrou que a extração aquosa à quente não foi um método eficiente, resultando em um EAT (equivalente de ácido tânico) de 1,0328 mg/mL. Proporcional à concentração de polifenóis, a atividade antioxidante foi baixa, não ultrapassando 5,0% de atividade em relação ao ácido ascórbico.
Cutaneous aging is related to the action of free radicals, which appear in greater quantity as a consequence of senescence, so that natural defenses cannot eliminate them. The aim of this study was to develop a non-ionic emulsion containing an aqueous extract of the inner bark of Lafoensia pacari A. St.-Hil. and assess its physicochemical stability, as well as its antioxidant activity. The aqueous extract was prepared under reflux with a 1:25 ratio of bark:distilled water (w/v). The total polyphenol content was determined by the Folin-Ciocalteau method, with tannic acid as standard. BHT, ascorbic acid and the aqueous extract were incorporated into the non-ionic emulsion, each of them at a concentration of 1%, the first two being. used as reference substances. Antioxidant activity was analyzed by the phosphomolybdenum method, each emulsion being first diluted in water to 400 ìg / mL. The addition of aqueous extract of L. pacari did not significantly affect the stability of the cream over the period of analysis. The content of polyphenols showed that hot aqueous extraction was not an efficient method, resulting in a tannic acid equivalent (TAE) of 1.0328 mg/mL in the crude extract. Proportional to the polyphenol concentration, the antioxidant activity was also low, not exceeding 5.0% of the activity of the ascorbic acid.
Subject(s)
Antioxidants , Free Radicals , Pharmaceutic AidsABSTRACT
The influence of seasonal climatic changes on tannin concentrations was examined in two caatinga (semi-arid) plant species (Myracrodruon urundeuva (Engl.) Fr. All. and Anadenanthera colubrina (Vell.) Brenan). The Folin-Ciocalteau method was used to quantify total phenols, and the casein precipitation method was used for tannins. In general, there is a close relationship between tannin levels and rainfall, although species seem to adopt different strategies of tannin compound production in response to periods of drought and rainfall in the caatinga.
Examinou-se a influência da sazonalidade climática sobre as concentrações de taninos em duas espécies da Caatinga: Myracrodruon urundeuva (Engl.) Fr. All. e Anadenanthera colubrina (Vell.) Brenan. Empregou-se o método Folin-Ciocalteau para quantificar os fenóis totais e o método de precipitação da caseína para taninos. De maneira geral, existe uma forte relação entre os teores de taninos e a pluviosidade, apesar das espécies parecerem adotar diferentes estratégias de produção de compostos tânicos em resposta aos períodos de seca e chuva na caatinga.