The research of biofilm and some enzymes in yeasts isolated from raw milk

Microbial quality of raw milk is important for the production of high quality and healthy milk and milk products. Yeast contamination in dairyadversely affects quality, functionality, and safety of the products produced. Biofilm is very important because of the effects as well as industry and on health in the food industry. Biofilm should be contamination of the product and subject to corrosion pipes in operation. At the same time biofilm forming microorganisms can be become colonized with used in thebiomaterials and lead to septicemia microorganisms. In our study 73 yeasts were isolated from 100 samples of raw milk. The isolated species have been as 12 C. kefyr, 11 C. lipolytica, 5 C.guiliermondii, 4 C.rugosa, 3 C.intermedia, 2 C.lusitaniae, 10 Tri.beigelii, 7 Tri.capitatum, 8 S.cerevisiae, 6?sı Cr.neoformans, 1 Cr.albidus, 1 Cr.neoformans var uniguttulatus, 3 Rho.rubra. This isolates have investigated the presence of biofilms, slime formation and the formation of the enzyme phospholipase. Biofilm study that used crystal violet, after 48 hours, biofilm formation was determined in 19 Candida, 9 Trichosporon, 7 Saccharomyces, 5 Cryptococcus and 2 Rhodotorula. After 48 hours, biofilm formation was determined in 22 Candida, 12 Trichosporon, 7 Saccharomyces, 5 Cryptococcus ve 3 Rhodotorula. Study of slime factor formation was in used Standart Glass Tube Method and Kongo Red Agar method. In our study, slime factor that used method of a standard glass tube method was determined in 13 Candida, 6 Trichosporon, 3 Cryptococcus, 4 Sachharomyces; in the study slime factor with method of Kongo red agar was determined in 15 Candida, 7 Trichosporon, 3 Cryptococcus, 5 Sachharomyces ve 1 Rhodotorula. Egg yolk containing agar method of working enzyme phospholipase was identified in 20 isolates of 73 yeasts. Showing the phospholipase activity of 20 microorganisms are 4 Candida, 3 Trichosporon, 5 Sachharomyces, 5 Cryptococcus and 3 Rhodotorula. As a result, yeasts isolated from raw milk indicates that contamination of milk and milk operations. Yeast?s presence of biofilm, slime and phospholipase reveals its importance in human health and operation.Key Words : Raw milk, yeast, biofilm, slime, phospolipase