Phytochemical Screening and Antimicrobial Activity Evaluation of Aqueous and Ethanolic Extracts of the Leaf of Azadirachta indica Juss (neem) on some Microorganisms

Abstract

Azadirachta indica Juss (neem) is a plant which has been used for a long time as traditional medicine for household remedy against various human ailments from antiquity. To evaluate the scientific basis for the use of Azadirachta indica, both aqueous and ethanolic extracts of the dried leaves of the plant were subjected to phytochemical screening and determination of anti-microbial activity on six different species of bacteria and a fungus. The phytochemical screening of the aqueous and ethanolic extracts of dried powdered leaves of the plant was done using standard methods. The antimicrobial activity of the concentrated extracts was evaluated by determination of the diameter of zone of inhibition against the microorganisms using agar well diffusion method. The Phytochemical screening of the test plant revealed the presence of saponins, alkaloids, cardiac glucosides, phenols, resins, tannins, terpenes and steroids. Although, both plant extracts had antimicrobial effects against the test organisms, the aqueous extracts were found to show greater anti-microbial effect than ethanolic extract. Thus, the mean diameter zones of inhibition ranged from 0.03mm-40.00mm for aqueous extract and 0.50mm-21.00mm for ethanolic extract at the highest concentration of 50mg/ml. The finding of this study supports the use of neem leaf in the treatment of various microbial infections by alternative systems of medicine.