纳他霉素与山梨酸复配改良MRS培养基的研究

对不同浓度纳他霉素（Natamycin）与山梨酸（Sonic Acid）及其复配后在MRS培养基中防止杂菌生长的情况进行了研究，结果表明，单独使用10mg／L纳他霉素可防止MRS培养基中真菌的生长；单独使用2000mg／L山梨酸可抑制真菌及常见细菌的生长；纳他霉素与山梨酸复配后可适当降低二者的使用浓度并具有协同增效的作用；但均没有抑制乳酸菌的生长，由此初步得到了一种新的改良MRS培养基。

Improvement of MRS medium by co-addition of Natamycin and Sorbic acid

The inhibition effects of Natamycin, Sorbic acid or their mixture added at different concentrations in MRS medium on the growth of contaminative bacteria were investigated. It was indicated that 10 mg/L Natamycin could inhibit the growth of fungi in MRS medium effectively. When 2000 mg/L Sorbic acid was added in MRS medium alone, the growth of fungi and common bacteria were suppressed. Ifnatamycin and sorbic acid were co-added, their effective concentrations could be decreased for their synergistic action. Whatever, the inhibition on the growth of lactic acid bacteria was not observed no matter Natamycin and Sorbic acid were added into the MRS medium separately or simultaneously. Hence, a newly improved MRS medium was obtained.