Study of Hydrophobicity and Autoaggregation of Lactobacillus acidophilus Isolated from vagina

The Hydrophobicity of the seven isolates of L.acidophilus were detected by applying BATH test (Bacterial Adherence To Hydrocarbons) using xylene. The percentage of Hydrophobicity of the isolates ranged between 28-88% and the differences between the rates were significant (P<0.05). There was three hydrophobic isolates. The autoaggregation ability of the three isolates was tested by using the supernatant of MRS and LAPTg media in which the bacteria was cultivated for 24 hr. The results revealed that the three isolates were more aggregative in LAPTg supernatant. The percentage of the aggregation ranged between 70- 83.3% .On the other hand the percentage of the autoaggregation using MRS supernatant ranged between 30-70%. The nature of the surface and secreted factors which are responsible for the autoaggregation were determined by treatment of the bacterial cells and their LAPTg supernatants by proteinase K, lipase and sodium periodate. Results obtained indicated that the two types of these factors were proteins because of the inhibition of the aggregation after either the treatment of cells or the supernatants by proteinase K, and it's resistance to treatment with lipase or sodium periodate.