Biosafety of Handling of Some Pathogenic Bacteria


Yeast extract peptone glucose medium (YPG) was the best medium for higher fungal biomass production and chitosan production. The chitosan was extracted by using a two-steps biological treatment process: demineralization by lactobacillus plantarum and deproteinization by Pseudomonas aeruginosa. Chitosan exhibited a strong antibacterial effect on the gram-positive bacteria than gram-negative since the inhibition rates were 47 and 50% against Staphylococcus aureus and Bacillus cereus, respectively, also the growth inhibition effect by chitosan against fungi was not strong as in the case of bacteria. So that Pseudomonas aeruginosa, that has frequently multi drug resistant and contribution to the high morbidity and mortality of patients, may be used as useful tool in biological treatment for deproteinization and extraction of chitosan that has a promising applications in the medical field.