Phytochemical Composition, Antioxidant and Xanthine Oxidase Inhibitory Activities of Amaranthus cruentus L. and Amaranthus hybridus L. Extracts.

This paper describes a preliminary assessment of the nutraceutical value of Amaranthus cruentus (A. cruentus) and Amaranthus hybridus (A. hybridus), two food plant species found in Burkina Faso. Hydroacetonic (HAE), methanolic (ME), and aqueous extracts (AE) from the aerial parts were screened for in vitro antioxidant and xanthine oxidase inhibitory activities. Phytochemical analyses revealed the presence of polyphenols, tannins, flavonoids, steroids, terpenoids, saponins and betalains. Hydroacetonic extracts have shown the most diversity for secondary metabolites. The TLC analyses of flavonoids from HAE extracts showed the presence of rutin and other unidentified compounds. The phenolic compound contents of the HAE, ME and AE extracts were determined using the Folin-Ciocalteu method and ranged from 7.55 to 10.18 mg Gallic acid equivalent GAE/100 mg. Tannins, flavonoids, and flavonols ranged from 2.83 to 10.17 mg tannic acid equivalent (TAE)/100 mg, 0.37 to 7.06 mg quercetin equivalent (QE) /100 mg, and 0.09 to 1.31 mg QE/100 mg, respectively. The betacyanin contents were 40.42 and 6.35 mg Amaranthin Equivalent/100 g aerial parts (dry weight) in A. cruentus and A. hybridus, respectively. Free-radical scavenging activity expressed as IC50 (DPPH method) and iron reducing power (FRAP method) ranged from 56 to 423 µg/mL and from 2.26 to 2.56 mmol AAE/g, respectively. Xanthine oxidase inhibitory activities of extracts of A. cruentus and A. hybridus were 3.18% and 38.22%, respectively. The A. hybridus extract showed the best antioxidant and xanthine oxidase inhibition activities. The results indicated that the phytochemical contents of the two species justify their traditional uses as nutraceutical food plants.

Antioxidant and anti-inflammatory effects of Scoparia dulcis L.

Different extracts were obtained from Scoparia dulcis L. (Scrophulariaceae) by successive extraction with hexane, chloroform, and methanol. These extracts exhibited significant antioxidant capacity in various antioxidant models mediated (xantine oxidase and lipoxygenase) or not mediated (2,2-diphenyl-picrylhydrazyl, ferric-reducing antioxidant power, ß-carotene bleaching, lipid peroxidation) by enzymes. The antioxidant activity of the extracts was related to their phytochemical composition in terms of polyphenol and carotenoid contents. The chloroform extract was richest in phytochemicals and had the highest antioxidant activity in the different antioxidant systems. All the extracts exhibited less than 50% inhibition on xanthine oxidase but more than 50% inhibition on lipid peroxidation and lipoxygenase. The extracts strongly inhibited lipid peroxidation mediated by lipoxygenase.

Polyphenol content and antioxidant activity of fourteen wild edible fruits from Burkina Faso.

A total of fourteen (14) species of wild edible fruits from Burkina Faso were analyzed for their phenolic and flavonoid contents, and their antioxidant activities using the DPPH, FRAP and ABTS methods. The data obtained show that the total phenolic and total flavonoid levels were significantly higher in the acetone than in the methanol extracts.Detarium microcarpum fruit had the highest phenolic and the highest flavonoid content,followed by that of Adansonia digitata, Ziziphus mauritiana, Ximenia americana and Lannea microcarpa. Significant amounts of total phenolics were also detected in the other fruit species in the following order of decreasing levels: Tamarindus indica > Sclerocaryabirrea > Dialium guineense > Gardenia erubescens > Diospyros mespiliformis > Parkiabiglobosa > Ficus sycomorus > Vitellaria paradoxa. Detarium microcarpum fruit also showed the highest antioxidant activity using the three antioxidant assays. Fruits with high antioxidant activities were also found to possess high phenolic and flavonoid contents. There was a strong correlation between total phenolic and flavonoid levels and antioxidant activities.