Antimicrobial, Cytotoxic and Phytotoxic Potency of Ethyl Acetate Extract of Rhizopus stolonifer Culture

Mudassar Iqbal¹*, Muhammad Amin¹, Zafar Iqbal¹, Hamida Bibi², Amjad Iqbal³, Zia-ud Din⁴, Muhammad Suleman¹ and Hamid Ullah Shah¹

¹Department of Agricultural Chemistry, ²Department of Soil and Environmental Sciences, The University of Agriculture, Peshawar, Pakistan , ³Science and Advice for Scottish Agriculture, Edinburgh, EH12 9FJ, United Kingdom, Department of Human Nutrition, The University of Agriculture Peshawar

*For correspondence: Email: mudassariqbal@aup.edu.pk; Tel: +92 346 9211142; Fax: +92 91 9216520  

Received: 14 January 2013                                                                   Revised accepted: 7 November 2013

Tropical Journal of Pharmaceutical Research, January 2014; 13(1): 87-92

Purpose: To evaluate the antimicrobial, cytotoxic and phytotoxic activities of the organic extract of Rhizopus stolonifer whole cell static culture in order to determine the presence of potentially bioactive compounds in the culture.

Methods: The organic extract was obtained by extracting the whole cell culture of R. stolonifer with Ethyl Acetate (EtOAc). The antifungal activity was determined by inhibitory effect on the growth of Alternaria alternate, Aspergillus flavus, Curvularia protuberata and Fusarium oxysporum, cytotoxic activity by brine shrimp lethality test, antibacterial activity against Ervinia carotovora and Xanthomonas campestris by disc diffusion technique, and phytotoxic activity by testing the crude extract against the Lemna minor frond.

Results: The extract showed phytotoxic activity (at 95% level of significance) against Lemna minor (67.7 % lethality) with Fronds Inhibition (FI₅₀) of 167.85 µg mL^-1. The extract exhibited a significant (at 95% level of significance) cytotoxic activity (LC₅₀ of 115.71 µg mL^-1) against brine shrimp. Maximum mortality (56.7 %) was obtained at a concentration of 200 µg mL^-1 concentration after 48 h. In the antifungal test, the highest inhibitory effect was observed against Fusarium oxysporum (88.8 %) followed by Alternaria alternata (81.5 %), Aspergillus flavus (70.5 %) and Curvularia protuberata (37.5 %) at 1000 µg. mL^-1 when compared to negative reference. Antibacterial activity against Ervinia carotovora and Xanthomonas campestris was minimal even at extract level of 2000 µg mL^-1.

Conclusion: The ethyl acetate extract of R. stolonifer possesses significant herbicidal, cytotoxic and antifungal properties. Isolation and characterization is required for structural elucidation of its bioactive compounds.

Keywords: Rhizopus stolonifer, Antifungal, Antibacterial, Phytotoxicity, Cytotoxicity