4.5. Antifungal Activity

The antifungal activity of crude extracts of A. ochraceus in the case of 0, 15%, and 30% seawater was evaluated against phytopathogenic Fusarium oxysporum RCMB 08213, which was purchased from the Regional Center of Mycology and Biotechnology, Al-Azhar University, Cairo, Egypt. The antifungal activity was evaluated according to the method used by Khalil et al. [45], with modifications. Additionally, the minimum inhibitory concentration (MIC) for each extract was determined using the broth micro-dilution method [105]. Initially, 100 μL of broth medium was added in a 96-well plate. Fungal suspensions were prepared to be 107 spores/mL and were cultured in a 96-well plate containing a broth medium. Two-fold serial dilutions of crude extracts of A. ochraceus were performed to obtain a final concentration range from 1000 to 0.008 µg/L, and 100 μL was added to each dilution. The microtiter plates with 96 U wells were incubated for 3 days at 30 °C.