产广谱细菌素马里乳杆菌菌株的筛选和鉴定

Screening and identification of broad spectrum bacteriocin-producing lactic acid bacterium

从冷藏鲜肉制品中分离筛选到36株乳酸菌,通过牛津杯法从中筛选出1株对指示菌具有明显抑菌作用的菌株,排除有机酸、过氧化氢等干扰因素后,该菌株发酵液仍有很强的抑菌作用。用胃蛋白酶处理后,发酵液抑菌活性急剧下降,因而确定该抑菌物质具有蛋白质性质,是一种细菌素。抑菌谱实验测定表明,此菌株的发酵液不仅抑制革兰阳性菌,而且对革兰阴性菌以及酵母菌和芽孢杆菌也有抑制作用,是一类广谱细菌素。结合形态学、生理生化特性分析,该菌株被初步鉴定为马里乳杆菌。

Thirty six lactic acid bacteria were isolated from meat stored in low temperature, and one which showed strong inhibitory activity against the indicated bacteria were screened through agar diffusion test. The supernatant of this strain could inhibit the growth of indicator strain strongly after excluding hydrogen peroxide and organic acid. But the inhibitory activity decreased sharply after treatment with pepsin, which indicated that this inhibitory material obtained the feature of protein, it could be classified as bacteriocin. The test of bacterial inhibition spectrum proved that the supernatant of this strain could inhibit not only gram-positive bacteria but also gram-negative bacteria and yeast. Therefore, this strain produced a bacteriocin with wide inhibition spectrum. Through detection of its appearance, physiological and biochemical characteristics, it was identified as Lactobacillus mall.