戊糖乳杆菌素pentocin LPEM818的初步纯化及特性研究

摘要

对戊糖乳杆菌(Lactobacillus pentosus)LPEM818所产戊糖乳杆菌素(pentocin) LPEM818进行了初步纯化,并对其生物学特性进行了研究.结果表明,采用80％硫酸铵沉淀和Sephadex G-25凝胶层析分离纯化后,细菌素的纯化倍数为11.09倍,回收率为6.4％；该细菌素在pH 2.0 ～8.0条件下稳定,121℃加热15 min保留84.52％的抑菌活性；对胰蛋白酶和蛋白酶K敏感；该细菌素的作用方式为杀菌；对供试的部分革兰氏阳性菌(G+)和革兰氏阴性菌(G-)具有较强抑制作用,因其抑菌谱较广,对多数致病菌和食品腐败菌有较好抑菌作用,所以具有作为食品生物防腐剂的潜在应用价值.%The partial purification and characterization of pentocin LPEM818 produced by Lactobacillus pentosus LPEM818 were studied.Pentocin LPEM818 was purified by 80 % ammonium sulfate precipitation and Sephadex G-25 column chromatography.The results showed that an 11.09 fold purification and 4.6% yield were obtained.Pentocin LPEM818 exhibited strong heat stability (remained 84.52 % of the antibacterial activity after 15 min at 121 ℃ ) and pH stability (pH 2.0 ～8.0).The activity of pentocin LPEM818 was destroyed after treatment with proteinase K and trypsin.The mode of action of pentocin LPEM818 was bactericidal.Pentocin LPEM818 exhibited inhibitory activity a-gainst part of the Gram-positive bacteria and Gram-negative bacteria.The identified properties of pentocin LPEM818 indicate that it is a novel bacteriocin with potential application as a bio-preservative to improve the safety of food products.