链霉菌NG-715的抗真菌活性及稳定性研究

Bioactivity and stability study of the antifungal substance produced by Streptomyces NG-715

目的研究链霉菌NG-715的抗真菌活性及稳定性,建立其生物活性的检测方法。方法以链霉菌NG-715所产抗真菌组分为材料,测试其对啤酒酵母、桔青霉、黑曲霉、黑根霉的最低抑制浓度和最低杀灭浓度。以黑曲霉为指示菌,测其生物检测法和稳定性。结果链霉菌NG-715所产抗真菌组分对啤酒酵母、桔青霉、黑曲霉、黑根霉的最低抑制浓度和最低杀灭浓度分别为1.25、2.5、3.75、3.75μg/mL和2.5、10、17.5、17.5μg/mL。生物检测法求得抑菌圈直径(mm)-浓度(μg/mL)的对数值之间的线性回归方程为y=26.963x-27.6,R2=0.9991。该抗真菌组分耐热和酸碱,对紫外线较敏感。结论本研究为下一步对该抗真菌活性成分的分离提取提供了有益的试验数据。

Objective To explore the bioactivity and stability of the antifungal substance produced by Streptomyces NG-715 as well as to establish the assay for biological activity detection. Method Take the antifungal substance as experimental materials, and test its minimum inhibitory concentration and minimum bactericidal concentration on four fungi strains including Saccharomyces cerevisiae, Penicillium citrinum, Aspergillus niger, Rhizopus sp. Aspergillus niger was used as indicator strain to measure the biological activity and stability of the antifungal substance. Results The results showed that the MIC of the antifungal substance on four fungi strains including Saccharomyces cerevisiae,Penicillium citrinum,Aspergillus niger,Rhizopus sp were 1.25, 2.5, 3.75 and 3.75μg/mL, respectively. The MBC of the antifungal substance on four fungi strains were 2.5, 10, 17.5 and 17.5μg/mL, respectively. Linearity regress equation of the antifungal substance in Aspergillus niger was y=26.963 x-27.6,R 2=0.9991. The antifungal substance was pH-stable, heat-stable but ultravio1 et-sensible. Conclusion The results from this study will porvide useful information for the further extraction and analysis on the bioactive compound.