Streptomyces alboflavus TD-1产挥发性抑菌物质对黄曲霉菌生长及其毒素的抑制作用

Effects of Volatile Organic Compounds from Streptomyces alboflavus TD-1 against Aspergillus flavus Growth and Aflatoxin Production

利用双皿对扣和气相色谱-质谱法,研究白黄链霉菌TD-1(Streptomyces alboflavus TD-1)在不同葡萄糖浓度培养基中的生长和挥发性有机化合物(volatile organic compounds,VOCs)代谢规律,通过荧光显微镜、扫描电子显微镜及高效液相色谱等方法,研究1-辛烯-3-醇对黄曲霉菌的抑菌机制。结果表明,高浓度葡萄糖(500 mmol/L)培养条件下,白黄链霉菌TD-1的初始生长速率与VOCs产生能力受到明显抑制,当葡萄糖浓度降至50 mmol/L左右,抑制得到解除。利用气相色谱-质谱分析发现,白黄链霉菌TD-1所产生的有效抑菌VOCs包括己醛、1-辛烯-3-醇、2-正戊基呋喃、2-甲基异冰片和苯乙酮等。其中,食品级VOCs 1-辛烯-3-醇在用量15μL/L时可完全抑制黄曲霉的生长,对黄曲霉菌丝体和孢子形态具有明显的致畸作用,可破坏线粒体膜,抑制黄曲霉毒素B1合成速率至31.98%。说明葡萄糖浓度会影响白黄链霉菌TD-1生长和VOCs产量;1-辛烯-3-醇具有抑制黄曲霉菌生长和黄曲霉毒素B1合成的作用。

The growth of Streptomyces alboflavus TD-1 in Gauze’s modified medium with different concentrations of glucose was evaluated by double-dish buckle,and the volatile organic compounds(VOCs)produced by it including 1-octen-3-ol were determined by gas chromatography-mass spectrometry(GC-MS).The antimicrobial mechanism of 1-octen-3-ol against Aspergillus flavus was determined by fluorescence microscopy(FM),scanning electron microscopy(SEM)and high performance liquid chromatography(HPLC).The results showed that the initial growth rate and VOCs production capacity of S.alboflavus TD-1 were severely inhibited by high concentration of glucose(500 mmol/L),but when the glucose concentration was decreased to 50 mmol/L,this inhibition was removed.The antibacterial VOCs produced by S.alboflavus TD-1 included hexanal,1-octen-3-ol,2-pentylfuran,and 2-methylisobornyl and acetophenone.Food-grade 1-octen-3-ol completely inhibited the growth of A.flavus at a concentration of 15μL/L,which had an obvious teratogenic effect on the mycelium and spore morphology of A.flavus,seriously damaged the mitochondrial membrane,and significantly reduced the synthesis rate of AFB1 to 31.98%.Therefore,the concentration of glucose in the medium can affect the growth of S.alboflavus TD-1 and the production of VOCs;1-octen-3-ol can effectively inhibit the growth of A.flavus and the synthesis of AFB1.