Biochemical Studies Of Secondary Metabolite Of Penicillium Chrysogenum Grown On Selected Agro-Wastes

ABSTRACT

Selected agro-wastes found in Lagos, Nigeria (cassava peels, corncob, sawdust, and sugarcane pulp) were compared with glucose and lactose as microbial substrates for cultivating P. chrysogenum (wild strain). This study was designed to give added value to agro waste as substrates to cultivate P. chrysogenum and subsequent production of secondary metabolite with antibiotic and anticoagulant properties. In the growth studies, corn cob and cassava peels significantly (p < 0.05) produced the highest amount of mycelia weight. Corn cob yielded a mycelia weight of 0.15 ± 0.02 and 0.92 ± 0.04mg/ml on the third and ninth day respectively while cassava peels yielded a mycelia weight of 0.13 ± 0.07 and 0.12 ± 0.02mg/ml on the third and twelfth day respectively. Mycelia weight of the organism, in media containing glucose, sugar cane and lactose was 0.12 ± 0.02, 0.068 ± 0.05 and 0.055 ± 0.03mg/ml respectively, was highest on the ninth day. Sawdust gave the least growth with a mycelia weight of 0.07 ± 0.01mg/ml on the third day. Cassava media has the highest carbohydrate content. Changes in extracellular protein secreted into the different media (every 3days for 21days) shows that culture media containing cassava peels gave the highest protein peak of 0.38 ± 0.08 mg/ml on the sixth day, while corncob gave an early peak of 0.30 ± 0.03mg/ml on the third day. Sawdust gave two protein peaks, 0.15 ± 0.03 on the third day and 0.25 ± 0.01mg/ml on the twelfth day. A total protein yield of 0.2 ± 0.05, 0.08 ± 0.02, 0.06 ± 0.02 mg/ml respectively was obtained with glucose, sugarcane pulp and lactose containing media on the third day. The results suggest that cassava peels, corncob and sugarcane pulp could serve as cheap fermentation substrates for the growth of the fungus. Optimum pH and temperature of growth and antibiotic production was 6.5 and 25OC respectively.