Preliminary Phytochemical, Antimicrobial and Acute Toxicity Studies of the Stem, bark and the Leaves of a cultivated Syzygium cumini Linn. (Family: Myrtaceae) in Nigeria

Abstract

The phytochemical, antimicrobial and acute toxicity studies of the leaf and stem bark extracts of Syzygium cumini Linn. grown in Abuja, Nigeria was carried out. The phytochemical screening revealed the presence of carbohydrates, saponins, tannins, terpenes, volatile oil, sterols, resins balsam, phlobatanins and flavonoids in the leaves and stem bark of the species studied. Alkaloids and anthraquinones were absent in all the plant parts studied. 70% methanol extracts were used for antimicrobial and acute toxicity studies. The six test organisms used for antimicrobial studies were: Pseudomonas auriginosa, Escherichia coli, Staphylococcus aureus, Candida albicans, Bacillus subtilis and Salmonella typhii. The oil from the leaves showed activity on all the test organisms; the leaf extract showed activity on all test organisms except P. auriginosa while the stem bark extract showed no activity on any of the test organisms used. The oil had a saponification value of 363 and an acid value of 4.21. The lethal dose 50% (LD50) in mice was found to be >5000 mg/kg for the stem bark and at 3,873 mg/kg for the leaf extracts.

Key words: Phytochemical, antimicrobial, acute toxicity, Syzygium cumini, Nigeria.