Biological activities of different neem leaf crude extracts used locally in Ayurvedic medicine

Abstract

Neem (Azadirachta indica) is widely used in the Ayurvedic medicine system for treating malaria and fever. The present study was undertaken to prepare crude extracts of neem leaves with different polarity organic solvents by using a maceration method and assessing phytochemical screening, the total phenol content and antioxidant activity by the spectroscopic method. The leaf samples collected from the Bahla, Ad Dakliyah region were used for extraction by a maceration method using different organic solvents with increasing polarities. Biochemical screening was determined by established methods. The total phenol content and free radical scavenging activity were assessed by conventional Folin–Ciocalteu reagent (FCR) and α, α-diphenyl-β-picrylhydrazyl (DPPH) methods. Biochemical screening of the crude extracts of neem leaves revealed positive results of flavonoids, saponins, steroids, alkaloids, amino acid and tannins. However, triterpenoid and anthraquinone were not detected in the crude extracts of neem leaves. The total phenol content of crude extracts from the leaves of the plant selected to be the gallic acid equivalent was found to be the highest in the ethyl acetate extract containing phenol compounds (3.58 g/100 g of dry powder) and the lowest in the water extract (0.42 g/100 g of dry powder). The highest antioxidant activity was found in the butanol extract and the lowest was in the hexane extract of the plant selected to be equivalent to DPPH. The crude extracts of neem showed significant antioxidant activity; thus, these extracts could be used as natural antioxidants for the preparation of medicines to treat different diseases.