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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469402

RESUMO

Abstract This study explores the antioxidant activity, phytochemical screening, total phenolic and flavonoids contents in the extracts of four locally available weeds plants namely Convolvulus arvensis, Chenopodium murale, Avena fatua and Phalaris minor with different solvents. The antioxidant activities of these extracts were determined via various in-vitro methods such as total antioxidant activity (TAA), reducing power (RP), DPPH (2,2-Diphenyl-1-Picrylhydrazyl) free radical scavenging and hydrogen peroxide scavenging assays. Phytochemical screening was performed both qualitatively as well as quantitatively. Total phenolic content (TPC) and total flavonoid content (TFC) were determined through Folin- Ciocalteu reagent and aluminium chloride methods respectively. Methanol-chloroform solvent showed the presence of a high amount of TPC in milligram of gallic acid equivalent per gram of dry weight (mg of GAE/g of DW) in the extracts of all weeds. Their descending sequence was Avena fatua (74.09) Phalaris minor (65.66) Chenopodium murale (64.04) Convolvulus arvensis (61.905), while, chloroform solvent found to be best solvent for the extraction of TFC. Methanol-chloroform solvent was also found to be best solvent for TAA (Total antioxidant activity assay) which showed values in milligram of ascorbic acid equivalent per gram of dry weight (mg of AAE /g of DW), for DPPH scavenging activity, reducing power (antioxidant activity) and hydrogen peroxide scavenging activity. Phytochemical screening indicated the presence of polyphenols, flavonoids, tannins, saponins, alkaloids and glycosides in these weeds.


Resumo Este estudo investiga a atividade antioxidante, a triagem fitoquímica, os teores de fenólicos totais e de flavonoides nos extratos de quatro plantas daninhas disponíveis localmente, quais sejam, Convolvulus arvensis, Chenopodium murale, Avena fatua e Phalaris minor com diferentes solventes. As atividades antioxidantes desses extratos foram determinadas por meio de vários métodos in vitro, tais como atividade antioxidante total (TAA), poder redutor (RP), sequestro de radicais livres DPPH (2,2-Difenil-1-Picril-hidrazil) e ensaios de sequestro de peróxido de hidrogênio. A triagem fitoquímica foi realizada tanto qualitativamente quanto quantitativamente. O teor de fenólicos totais (TPC) e o teor de flavonoides totais (TFC) foram determinados pelos métodos do reagente de Folin-Ciocalteu e do cloreto de alumínio, respectivamente. O solvente metanol-clorofórmio mostrou a presença de elevada quantidade de TPC em miligramas de ácido gálico equivalente por grama de peso seco (mg de GAE/g de DW) nos extratos de todas as plantas daninhas. Sua sequência descendente foi Avena fatua (74,09) Phalaris minor (65,66) Chenopodium murale (64,04) Convolvulus arvensis (61,905), enquanto o solvente clorofórmio foi o melhor solvente para a extração de TFC. O solvente metanol-clorofórmio também foi considerado o melhor solvente para AAT (ensaio de atividade antioxidante total), que apresentou valores em miligramas de equivalente de ácido ascórbico por grama de peso seco (mg de AAE/g de DW), para atividade sequestrante de DPPH, RP (atividade antioxidante) e atividade de sequestro de peróxido de hidrogênio. A triagem fitoquímica indicou a presença de polifenóis, flavonoides, taninos, saponinas, alcaloides e glicosídeos nessas plantas daninhas.

2.
Bol. latinoam. Caribe plantas med. aromát ; 21(4): 446-454, jul. 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1526668

RESUMO

Aromatic and medicinal plants are of great importance to determine the contents of the active compounds of plant origin and to evaluate them depending on variety and climate factors in order to determine the phenolic, antioxidant enzyme activity, vitamin contents in species belonging to the Lamiaceae family. Examination of the characteristics of different species, the highest peroxidase (POD) enzyme activity, ascorbate peroxidase (AxPOD), total antioxidant (TA), malondialdehyte (MDA), caffeic acids (CA), vitamin C contents,and chloric acid (ChA) were obtained in the M. longifoliaspecies. The highest vitamin E and catalase (CAT) were determined in the S. hortensisspecies but the highest total phenolic (TP), superoxide dismutase (SOD) enzyme, hydrogen peroxide (H2O2) and chlorogenic acid (ChgA) were determined in the S. spicigeraspecies. As a result of PCA analysis, it can be said that Mentha longifolia(L.) Hudson and Satureja spicigeraspecies have significant value in terms of biochemical and phenolic content.


Las plantas aromáticas y medicinales son de gran importancia para determinar el contenido de los compuestos activos de origen vegetal y evaluarlos en función de la variedad y factores climáticos con el fin de determinar la actividad enzimática fenólica, antioxidante, contenido vitamínico en especies pertenecientes a la familia Lamiaceae. El examen de las características de diferentes especies, la mayor actividad enzimática de peroxidasa (POD), ascorbato peroxidasa (AxPOD), antioxidante total (TA), malondialdehído (MDA), ácidos cafeicos (CA), contenido de vitamina C y ácido clorhídrico (ChA) se obtuvieron en la especie M. longifolia. La mayor cantidad de vitamina E y catalasa (CAT) se determinó en la especie S. hortensis, pero la mayor cantidad total de enzima fenólica (TP), superóxido dismutasa (SOD), peróxido de hidrógeno (H2O2) y ácido clorogénico (ChgA) se determinó en la especie S. spicigera. Como resultado del análisis de PCA, se puede decir que las especies Mentha longifolia(L.) Hudson y Satureja spicigeratienen un valor significativo en términos de contenido bioquímico y fenólico.


Assuntos
Fenóis/química , Vitaminas/química , Lamiaceae/metabolismo , Lamiaceae/química , Antioxidantes/química , Plantas Medicinais/metabolismo , Plantas Medicinais/química
3.
Acta sci., Biol. sci ; 43: e57080, 2021. graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460993

RESUMO

Fermented foods have made important contributions to human diets for thousands of years and continue to do so. Their health-promoting benefits are attracting increasingly attention. The present study was conducted to evaluate the impact of natural fermentation on antioxidant properties of traditionally fermented wheat (Triticum durum) compared to unfermented samples. Initially, the samples were submitted to traditional spontaneous fermentation. Subsequently, an aqueous extract was obtained and used to determine polyphenolic and flavonoid contents. Moreover, the antioxidant potential was also measured through the determination of the scavenging ability against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals, reducing power and hydrogen peroxide scavenging activity. The results showed that the total phenolic and total flavonoid contents were significantly increased in fermented wheat. Moreover, the antioxidant activity was more effective in fermented than in unfermented wheat. Thus, natural fermentation can enhance natural antioxidants in wheat and transform it into a healthy food or ingredient with multi-functional properties which can be used in the food industry.


Assuntos
Antioxidantes , Compostos Fenólicos , Fermentação , Flavonoides , Triticum/química
4.
Artigo em Inglês | IMSEAR | ID: sea-163573

RESUMO

Aims: Emblica officinalis, locally known as Amla, is a highly nutritious seasonal fruit. The processed fruit could be an important dietary source of natural vitamin C with potent antioxidant activity. The aim of present investigation was to study factors influencing antioxidant potential of Amla and its products. Methodology: Three Indian varieties of Amla fruits in three ripening states (unripe, semi ripe and fully ripe) were analyzed for total phenolic contents, vitamin C as well as antioxidant potential. Two Amla products were studied over a period of 33 days for these parameters. Results: In the present data, the fully ripe stage of Amla had the highest value of vitamin C (804.4±0.8mg/100g) and polyphenols (1300.3±99.6mg/100g) than the unripe, semi ripe stages. The DPPH Scavenging activity was found to be highest in semi ripe stage. ABTS radical scavenging (IC50 values) of unripe, semi ripe and ripe were 18.5±0.0071, 34.7±0.026, 21.9±0.024 respectively. The stability study for syrup and pickle, processed from Amla fruit, demonstrated sharper decrease of the vitamin C content for pickle than decrease for syrup over the time 33 days but the polyphenols and the free radical scavenging activity remained the same over the time. Conclusion: The present study suggested that ripening stages influence the antioxidant potential of Amla fruit. The contents of vitamin C showed a significant decrease over time in syrup and pickle but the antioxidant potential remained unaffected.

5.
Artigo em Inglês | IMSEAR | ID: sea-152943

RESUMO

Modern civilization is facing more than hundreds of disorders associated with free radicals and natural antioxidants from non-edible plants are gaining importance to fight these disorders. The intention of this report is to evaluate a well known medicinal weed Ageratum conyzoides stems for its antioxidant and cytotoxic Effects. Antioxidant potentiality of the crude methanolic extract of the Ageratum conyzoides (AC) stems was investigated on DPPH scavenging activity, reducing ability, total antioxidant capacity as well as total phenolic contents. Cytotoxic study was done by brine shrimp lethality bioassay and vincristin sulphate was used as standard. The total phenols and total antioxidant capacity of AC was found to be 38.125 ± 2.01mg/g equivalent of gallic acid and 333.37 ± 4.22mg/gm equivalent of ascorbic acid, respec-tively. The percentage (%) scavenging of DPPH free radical of the extract was found to be concentration dependent with IC50 value 46.01 ± 2.23μg/ml while IC50 value of standard ascorbic acid was found to be 29.56 ± 0.11μg/ml. The reducing power of AC was found to be concentration dependent. The cytotoxicity exhibited by AC was found promising with LC50 value 1.32μg/ml, comparing with the LC50 (0.689μg/ml) values of vincristin sulphate. The present investigation suggests that Ageratum conyzoides possesses remarkable antioxidant and cytotoxic property.

6.
Artigo em Inglês | IMSEAR | ID: sea-167915

RESUMO

Modern civilization is facing more than hundreds of disorders associated with free radicals and natural antioxidants from non-edible plants are gaining importance to fight these disorders. The intention of this report is to evaluate a well known medicinal weed Ageratum conyzoides stems for its antioxidant and cytotoxic Effects. Antioxidant potentiality of the crude methanolic extract of the Ageratum conyzoides (AC) stems was investigated on DPPH scavenging activity, reducing ability, total antioxidant capacity as well as total phenolic contents. Cytotoxic study was done by brine shrimp lethality bioassay and vincristin sulphate was used as standard. The total phenols and total antioxidant capacity of AC was found to be 38.125 ± 2.01mg/g equivalent of gallic acid and 333.37 ± 4.22mg/gm equivalent of ascorbic acid, respec-tively. The percentage (%) scavenging of DPPH free radical of the extract was found to be concentration dependent with IC50 value 46.01 ± 2.23μg/ml while IC50 value of standard ascorbic acid was found to be 29.56 ± 0.11μg/ml. The reducing power of AC was found to be concentration dependent. The cytotoxicity exhibited by AC was found promising with LC50 value 1.32μg/ml, comparing with the LC50 (0.689μg/ml) values of vincristin sulphate. The present investigation suggests that Ageratum conyzoides possesses remarkable antioxidant and cytotoxic property.

7.
Asian Pacific Journal of Tropical Biomedicine ; (12): 8-16, 2013.
Artigo em Inglês | WPRIM | ID: wpr-312475

RESUMO

<p><b>OBJECTIVE</b>To evaluate the antioxidant activities and total phenolic contents of brown seaweeds belonging to Turbinaria spp. [Turbinaria conoides (T. conoides) and Turbinaria ornata (T. ornata) collected from Gulf of Mannar of southeastern coast of India in various in vitro systems.</p><p><b>METHODS</b>The antioxidant activity was evaluated using different in vitro systems, viz., 1, 1-diphenyl-2-picrylhydrazyl (DPPH), 2, 2'-azino-bis-3 ethylbenzothiozoline-6-sulfonic acid diammonium salt (ABTS), H2O2/HO radical scavenging, Fe(2+) ion chelating ability, and reducing potential. Folin-Ciocalteu method was used to determine the total phenolic content of the extracts, and the results were expressed as mg of gallic acid equivalents (GE)/g of the seaweed extracts. Thiobarbituric acid-reactive substances assay was employed to assess the ability of the seaweed extracts to inhibit lipid oxidation.</p><p><b>RESULTS</b>Ethyl acetate (EtOAc) fraction of T. conoides registered significantly higher phenolic content (105.97 mg GE/g) than that of T. ornata (69.63 mg GE/g). Significantly higher antioxidant potential as determined by DPPH (64.14%) radical scavenging activity was registered in EtOAc fraction of T. ornata. A higher ABTS(•+) radical scavenging (IC50 3.16 µg/mL), Fe(2+) chelating (IC50 0.46 mg/mL), H2O2 scavenging (IC50 4.25 mg/mL), lipid peroxidation inhibitory (TBARS, IC50 0.21 mg/mL), and reducing abilities (IC50 52.67 mg/mL) (P<0.05) were realized in EtOAc fraction of T. ornata than other fractions.</p><p><b>CONCLUSIONS</b>This study indicated the potential use of T. conoides and T. ornata as candidate species to be used as food supplements/functional foods to increase shelf-life of food items for human consumption, and nutraceuticals to deter deleterious free radical-induced life-threatening diseases.</p>


Assuntos
Antioxidantes , Química , Índia , Phaeophyceae , Química , Fenóis , Extratos Vegetais , Química , Especificidade da Espécie
8.
Asian Pacific Journal of Tropical Biomedicine ; (12): 8-16, 2013.
Artigo em Chinês | WPRIM | ID: wpr-672583

RESUMO

Objective: To evaluate the antioxidant activities and total phenolic contents of brown seaweeds belonging to Turbinaria spp. [Turbinaria conoides (T. conoides) and Turbinaria ornata (T. ornata) collected from Gulf of Mannar of southeastern coast of India in various in vitro systems. Methods:The antioxidant activity was evaluated using different in vitro systems, viz., 1, 1-diphenyl-2-picrylhydrazyl (DPPH), 2, 2′-azino-bis-3 ethylbenzothiozoline-6-sulfonic acid diammonium salt (ABTS), H2O2/HO radical scavenging, Fe2+ ion chelating ability, and reducing potential. Folin-Ciocalteu method was used to determine the total phenolic content of the extracts, and the results were expressed as mg of gallic acid equivalents (GE)/g of the seaweed extracts. Thiobarbituric acid-reactive substances assay was employed to assess the ability of the seaweed extracts to inhibit lipid oxidation. Results: Ethyl acetate (EtOAc) fraction of T. conoides registered significantly higher phenolic content (105.97 mg GE/g) than that of T. ornata (69.63 mg GE/g). Significantly higher antioxidant potential as determined by DPPH (64.14%) radical scavenging activity was registered in EtOAc fraction of T. ornata. A higher ABTS.+ radical scavenging (IC50 3.16 μg/mL), Fe2+ chelating (IC50 0.46 mg/mL), H2O2 scavenging (IC50 4.25 mg/mL), lipid peroxidation inhibitory (TBARS, IC50 0.21 mg/mL), and reducing abilities (IC50 52.67 mg/mL) (P<0.05) were realized in EtOAc fraction of T. ornata than other fractions. Conclusions: This study indicated the potential use ofT. conoides and T. ornata as candidate species to be used as food supplements/functional foods to increase shelf-life of food items for human consumption, and nutraceuticals to deter deleterious free radical-induced life-threatening diseases.

9.
Artigo em Inglês | IMSEAR | ID: sea-151025

RESUMO

This study was designed to evaluate the in vitro antioxidant activities of hexane, dichloromethane and methanol extracts of Salvia verticillata ssp. verticillata and spp. amasiaca. The samples were subjected to screening for their possible antioxidant activity by using 2,2- diphenyl-1-picriylhydrazyl (DPPH) and β-carotene/linoleic acid assays. The methanol extracts particularly found to posses strong antioxidant activities (IC50= 16.0 ± 3.01 and 12.1 ± 3.82 mg ml-1, respectively) whereas the dichloromethane extracts showed low activities. In the linoleic acid system, oxidation of the linoleic acid was moderately inhibited by the methanol extracts (61.3 ± 5.38 and 68.7 ± 1.82 %, respectively). Also, in methanol extracts of these plants have been determined amount of 9 phenolic compounds in different proportions and identified by the RP-HPLC method. These plants have high level of rosmarinic acid (37.1 and 24.83 mg/g, respectively) when compared with other components. Amounts of caffeic acid were determined as 9.82 and 8.69 mg/g, respectively. Our results showed that the high levels of rosmarinic and caffeic acid are more likely to be responsible for most of the observed antioxidant activities of Salvia species.

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