El-Shafei H A, Abd-El-Sabour H, Ibrahim N, Mostafa Y A
Microbial Chemistry Department, National Research Centre, Dokki, Cairo, Egypt.
Microbiol Res. 2000 Mar;154(4):321-31. doi: 10.1016/s0944-5013(00)80006-3.
100 lactic acid bacterial strains isolated from traditional fermented foods (yoghurt, milk cream, sour dough and milk) were screened for bacteriocin production. Twenty six strains producing a nisin-like bacteriocin were selected. Most of these isolates gave only a narrow inhibitory spectrum, although one showed a broad inhibitory spectrum against the indicator strains tested, this strain was determined as Lactococcus lactis. The influence of several parameters on the fermentative production of nisin by Lactococcus lactis was studied. Production of nisin was optimal at 30 degrees C and in the pH range 5.5-6.3. The effect of different sulphur and nitrogen sources on Lactococcus lactis growth and nisin production was studied. Magnesium sulfate and manganese sulfate were found to be the best sulphur sources while triammonium citrate was the best inorganic nitrogen source and meat extract, peptone and yeast extract were the best organic nitrogen source for nisin production.
对从传统发酵食品（酸奶、乳脂、酸面团和牛奶）中分离出的100株乳酸菌菌株进行了细菌素生产筛选。挑选出了26株产生类乳链菌肽细菌素的菌株。尽管其中一株对测试的指示菌株显示出较宽的抑制谱，但这些分离株中的大多数仅具有较窄的抑制谱，该菌株被鉴定为乳酸乳球菌。研究了几个参数对乳酸乳球菌发酵生产乳链菌肽的影响。乳链菌肽的生产在30℃和pH值5.5 - 6.3范围内最为适宜。研究了不同硫源和氮源对乳酸乳球菌生长及乳链菌肽生产的影响。发现硫酸镁和硫酸锰是最佳硫源；柠檬酸三铵是最佳无机氮源，而肉膏、蛋白胨和酵母提取物是生产乳链菌肽的最佳有机氮源。
