African Journal of Biotechnology Vol. 6 (15), pp. 1732-1739, 6 August 2007   

ISSN 1684–5315 © 2007 Academic Journals        

Full Length Research Paper

Comparative phytochemical evaluation, antimicrobial and antioxidant properties of Pleurotus ostreatus

Iwalokun, B. A.¹, Usen, U. A¹, Otunba, A. A.² and Olukoya, D. K.²

¹Departmernt of Biochemistry, Lagos state University, P. M. B 1087, Apapa Lagos, Nigeria.

²DANIFOL Biotechnology Consult, Lagos, Nigeria.

*Corresponding author. E-mail: bamwal@yahoo.com. Phone: 234-1-8504327.

Accepted 31 May, 2007

This study scientifically examined the phytochemistry, antioxidant and antimicrobial potencies of two organic extracts of Pleurotus ostreatus. Generally, both extracts were effective against 89.8% of the isolates tested with Bacillus subtilis (7.6 – 7.8 mm), Escherichia coli (7.6 – 8.2 mm) and Saccharomycee cerevisae (10.5 – 10.8 mm) exhibiting highest gram ±ve, gram –ve and fungal susceptibilities by agar well diffusion method, respectively. However, petroleum ether extract (PE) exhibited greater anti-gram negative bacterial activity than the acetone extract (AE) and further produced growth inhibition of these isolates in broth. Compared to PE, the acetone extract elicited higher total phenolic content and in vitro antioxidant capacity. Phytochemical analyses of the extracts revealed low to moderate levels of terpenoids, tannins, steroidal glycosides and carbohydrates, while flavonoids, alkaloids and cynogenic glycosides were not detected. The results indicate that P. ostreatus possesses antimicrobial and antioxidant potentials.

Key words: Pleurotus ostreatus, organic extracts, antimicrobial activity, antioxidant capacity, phytochemistry.