title: Rep-PCR characterization and biochemical selection of lactic acid bacteria isolated from the Delta area of Egypt.
abstract: 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.
authors.affiliation: Department of Dairy Science and Technology, Faculty of Agriculture, Alexandria University, Alexandria, Egypt. marim_elsaeed83@hotmail.com
authors.forename: Mariam
authors.initials: M
authors.lastname: Mohammed
authors.forename: Hossam
authors.initials: H
authors.lastname: Abd El-Aziz
authors.forename: Nadia
authors.initials: N
authors.lastname: Omran
authors.forename: Shimaa
authors.initials: S
authors.lastname: Anwar
authors.forename: Sameh
authors.initials: S
authors.lastname: Awad
authors.forename: Morsi
authors.initials: M
authors.lastname: El-Soda
mesh_terms: D000626:Aminopeptidases / Q000378:metabolism; D000818:Animals; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D003611:Dairy Products / Q000382:microbiology*; D004534:Egypt; D016983:Enterococcus / Q000145:classification / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D005516:Food Microbiology; D014644:Genetic Variation; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007778:Lactobacillus / Q000145:classification / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D017045:Lactococcus / Q000145:classification / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D008892:Milk / Q000382:microbiology; D016133:Polymerase Chain Reaction / Q000379:methods*; D011135:Polysaccharides, Bacterial; D013045:Species Specificity
chemical_list: D011135:Polysaccharides, Bacterial; D000626:Aminopeptidases