Phytochemical screening and evaluation of antioxidant, total phenolic and flavonoid contents in various weed plants associated with wheat crops

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.

Antioxidant and cytotoxic activities of Ageratum conyzoides stems.

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.

Evaluation of phenolic contents and antioxidant activities of brown seaweeds belonging to Turbinaria spp. (Phaeophyta, Sargassaceae) collected from Gulf of Mannar

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.

Antioxidant and cytotoxic activities of Ageratum conyzoides stems.

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.

Evaluation of phenolic contents and antioxidant activities of brown seaweeds belonging to Turbinaria spp. (Phaeophyta, Sargassaceae) collected from Gulf of Mannar

<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>