The aim of the present study was to assess the antifungal activity of seed oil of Ricinus communis, a tall, fast growing, branching perennial shrub that can grow up to 3m high. It is a medicinal plant widely used in the treatment of various diseases and ailments. The oil obtained from the seed is used in the treatment of piles, chronic dysentery, ringworm, itch and other skin diseases. 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 1.2, 2.4, 4.8 and 9.6μg/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 exhibit a concentration-dependent increase in antifungal activity and high relative percentage inhibition against L. sajor-caju compared to standard antifungal agent. These findings indicated that R. communis seed oil can be used as a preservative agent against white rot caused by L. sajor-caju.
