Mohammed Mariam, Abd El-Aziz Hossam, Omran Nadia, Anwar Shimaa, Awad Sameh, El-Soda Morsi
Department of Dairy Science and Technology, Faculty of Agriculture, Alexandria University, Alexandria, Egypt.
Int J Food Microbiol. 2009 Jan 15;128(3):417-23. doi: 10.1016/j.ijfoodmicro.2008.09.022. Epub 2008 Oct 8.
Samples of raw milk and traditional dairy products were collected from different rural areas in the Delta region. 170 isolates from these products were identified using repetitive genomic element-PCR (Rep-PCR) fingerprinting. The identified isolates were tested for efficiency of biomass production and separation, acidifying activity, autolytic and aminopeptidase properties, antagonistic activities and exopolysaccharide production. The obtained results revealed that the Lactobacillus delbrueckii subsp. lactis, Lactobacillus fermentum, Enterococcus faecium Lactobacillus delbrueckii subsp. bulgaricus, Lactobacillus paracasei subsp. paracasei, Lactobacillus plantarum and Lactococcus lactis subsp. lactis were the predominant species in Egyptian dairy products. Two percent of Lactococcus, 10% of Lactobacillus and 1% of Enterococcus isolates showed fast acidifying activity. Aminopeptidase and autolytic properties were generally higher for most Lactobacillus strains when compared to other strains. Among these species, lactobacillus paracasei subsp. paracasei was the highest in Aminopeptidase activity and autolytic properties. Antagonistic activity was detected in 40% of Lactococcus, 70% of Lactobacillus and 50% of Enterococcus isolates. Some isolates produced exopolysaccharides in milk and dairy products.
从三角洲地区不同农村地区采集了生乳和传统乳制品样本。使用重复基因组元件PCR（Rep-PCR）指纹图谱对这些产品中的170株分离株进行了鉴定。对鉴定出的分离株进行了生物量生产和分离效率、酸化活性、自溶和氨肽酶特性、拮抗活性以及胞外多糖生产的测试。所得结果表明，德氏乳杆菌乳酸亚种、发酵乳杆菌、粪肠球菌、德氏乳杆菌保加利亚亚种、副干酪乳杆菌副干酪亚种、植物乳杆菌和乳酸乳球菌乳酸亚种是埃及乳制品中的主要菌种。2%的乳酸乳球菌、10%的乳杆菌和1%的肠球菌分离株表现出快速酸化活性。与其他菌株相比，大多数乳杆菌菌株的氨肽酶和自溶特性普遍较高。在这些菌种中，副干酪乳杆菌副干酪亚种的氨肽酶活性和自溶特性最高。在40%的乳酸乳球菌、70%的乳杆菌和50%的肠球菌分离株中检测到拮抗活性。一些分离株在牛奶和乳制品中产生胞外多糖。
