Department of Agricultural Microbiology and Food Technology sector, DIVAPRA, University of Turin, Italy.
Int J Food Microbiol. 2012 Feb 1;153(1-2):58-65. doi: 10.1016/j.ijfoodmicro.2011.10.016. Epub 2011 Oct 30.
In recent years, there has been a particular focus on the application of antimicrobial compounds produced by lactic acid bacteria (LAB) as natural preservatives to control the growth of spoilage and pathogenic bacteria in food. Bacteriocins are antimicrobial peptides which can be added to foods in concentrated forms as food preservatives, e.g. additives, or they can be produced in situ by starters or protective cultures. In this study, twenty Lactococcus lactis bacteriocin producers previously isolated from Italian fermented foods were subjected to a variety of physical and biochemical tests in order to identify those with the greatest potential as starter cultures in cheese production. Of these, four strains isolated from cheese (one nisin Z producer, one nisin A producer and two lacticin 481 producers) which fulfilled the desired technological criteria were assessed for their ability to control Listeria monocytogenes. The subsequent application of these bacteriocinogenic strains as starter cultures in Cottage cheese established that the nisin A producing Lact. lactis 40FEL3, and to a lesser extent the lacticin 481 producers 32FL1 and 32FL3, successfully controlled the growth of the pathogen. This is the first study to directly compare the ability of nisin A, nisin Z and lacticin 481 producing strains to control listerial growth during the manufacture and storage of Cottage cheese.
近年来，人们特别关注将乳酸菌（LAB）产生的抗菌化合物作为天然防腐剂应用于控制食品中腐败和致病菌的生长。细菌素是抗菌肽，可以以浓缩形式添加到食品中作为食品防腐剂，例如添加剂，或者可以由发酵剂或保护培养物原位产生。在这项研究中，从意大利发酵食品中分离出的二十种乳球菌细菌素产生菌经过各种物理和生化测试，以鉴定那些在奶酪生产中作为发酵剂最有潜力的细菌素产生菌。其中，从奶酪中分离出的四种菌株（一种产生尼辛 Z，一种产生尼辛 A，两种产生乳链菌肽 481）满足了所需的技术标准，用于评估其控制单核细胞增生李斯特菌的能力。随后将这些产细菌素的菌株作为发酵剂应用于干酪乳杆菌凝乳干酪中，结果表明，产尼辛 A 的乳球菌 40FEL3，以及产乳链菌肽 481 的菌株 32FL1 和 32FL3，成功地控制了病原体的生长。这是首次直接比较产尼辛 A、产尼辛 Z 和产乳链菌肽 481 的菌株在干酪乳杆菌凝乳干酪的生产和储存过程中控制李斯特菌生长的能力。
