Journal of Engineering Science and Technology (Mar 2009)
PHYSIOLOGICAL REGULATION OF PROTEASE AND ANTIBIOTICS IN PENICILLIUM SP. USING SUBMERGED AND SOLID STATE FERMENTATION TECHNIQUES
Abstract
A fungal strain belonging to the genus Penicillium was isolated from soil sample and has been diagnosed as Penicillium sp. according to its morphological characteristics of the colonies on solid media and also microscopical examination of the fungal parts. Antibiotics, protease activity and pH values were determined after cultivation of the fungus using submerged fermentation (SF) and solid state fermentation (SSF). The two different patterns of fermentation processes seem to influence the physiological behavior of the fungus differently. Experiments were made using nutrient broth medium (N.B) for SF and wheat bran in SSF. The pH values were adjacent to 5.5. Wheat bran was enriched with fish scales and egg shale in a ratio of (1:2:0.005 w/w) and the mixture was moistened by adding (30 ml) whey solution. After 7 days of incubation, the pH value of SF was increased to 8.0 at 30ºC. The SF was appeared efficient for antibiotics production. Using well diffusion technique the extracted antibiotics solution was active against some pathogenic bacteria such as Staphylococcus aureus, E. coli, Proteus sp., Salmonella sp., Pseudomonas aeruginosa and Streptococcus sp. In SSF relative proteases concentrations were found to be highly reactive than SF. This was proved by the appearance of the zone (20 mm and 32 mm) due to the hydrolysis of milk and blood proteins respectively using pH 5.5 at 30ºC for 24 hrs. The activity of proteases was (10.4 U/ml).
