Study on effects of the initial concentrations of ingredients in the starch – casein medium on production of antibiotics against the methicillin-resistant Staphylococcus aureus by Streptomyces flaveus

The bacterium Staphylococcus aureus is able to cause many diseases that are risky to human life. At present, the resistance of S. aureus to multiple antibiotics is a very difficult problem for healthcare industry in Vietnam and some other countries in the world. Streptomyces flaveus, an actinomycete isolated previously from the adjacent area of Ho Chi Minh City, is able to produce antibiotics against the methicillin-resistant S. aureus (MRSA). In this paper, we present the results of the investigation on effects of the initial concentrations of different ingredients in the stach – casein medium on fermentation by S. flaveus for production of antibiotics against the MRSA. While increasing the starch concentration, antibiotics produced were increased. Meanwhile, high concentrations of casein inhibited the actinomycete to produce antibiotics. For KNO3 and NaCl, both were neccesary for the antibiotic production. Though the increase in KNO3 concentration did not change the production of antibiotics against MRSA, the increase in NaCl concentration reduced the antibiotic production.