Maruf O. Yekeen, Olayiwola O. Ajala and Ahmed B. Alarape
The aim of the present study was to assess the antifungal activity of seed oil of Citrus sinensis, an evergreen tree belonging to the family Rutaceae family. It is the most commonly cultivated and commercialized species of citrus, and the fruits, by-products inclusive, have been reported to possess high medicinal and economic values. The oils extracted from the peels and seeds of C. sinensis have been reported to possess insecticidal and antimicrobial activity. The seed oil was tested for antifungal activity against Lentinus sajor-caju using agar disc diffusion method. The discs were loaded with 50μl of the oil extract at concentrations of 1.15, 2.3, 4.6 and 9.2μg/disc. Fluconazole (100μg/disc) was used as positive control while 95% methanol was used as negative control. The zone of inhibition was measured after incubation at 37oC for 24 hours. The percentage yield of the extracted oil was 32.4% and physicochemical analysis showed that it is of good quality. The seed oil exhibited a concentration-dependent increase in antifungal activity and high relative percentage inhibition against L. sajor-caju compared to standard antifungal agent. These results indicated that C. sinensis seed oil is highly effective as an antifungal agent against L. sajor-caju, which caused white rot in wood; therefore it can be used as a preservative agent for the management of wood infected with white rot fungi
