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 alternata , 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
