Phytochemicals content and in-vitro antioxidant properties of Azadirachta indica seeds, leaves and twigs prepared from different extraction techniques
The current study was design to exploit the Azadirachta indica leaves, seeds and twigs for %yield, phytochemicals content and antioxidant activities using infusion, hydroalcoholic, decoction and microwave extraction techniques. The phytochemicals contents were determined by standard reported methods. While antioxidant activity was assessed by three (03) standards In-vitro antioxidant test systems as 1, 1’-diphynyl- 2-picrylhydrazyl (DPPH), Hydrogen peroxide (H2O2) scavenging activity and Nitric oxide (NO) scavenging activity method using ascorbic acid as standard. The highest extractive yield was observed in seed were 44.00±02% (infusion), 38.00±00% (Hydroalcoholic) and 20.00±03% (decoction). Followed by leaves and twigs parts of neem. The high amount (+++) phytochemicals contents were extracted from neem leaves infusion and hydroalcoholic extracts as compared to seeds and twigs neem parts with decoction and microwave extraction methods. The highest Azadirachta indica (neem) leaves infusion extract showed at 1000 mg/L remarkably inhibited DPPH inhibition activity (85±01), H2O2 scavenging activity (83±01%), and NO scavenging activity (78±01%). The antioxidants activities showed a dose dependant manner, the higher the concentration showed high antioxidant activities. The results pointed to the significant antioxidant activities of the leaves infusion and hydroalcoholic extraction techniques, the overall strength being in the order of infusion >hydroalcoholic >decoction >microwave in leaves, seeds and twigs extracts. In all cases, the extracts obtained from leaves showed higher antioxidant activity and higher phytochemicals contents than the other extraction technique obtained from seeds and twigs. The results indicate that Azadirachta indica leaves, seeds and twigs extracts have potent antioxidant activities that would have beneficial effects on human health and infusion extracts are superior with better antioxidant potential.