Abstract
The aim was to study the microbiological quality of Domiaty and Hungarian cheeses, molecular identification and biofilm formation of some selected contaminant bacteria. Samples were collected from two M and P big markets in Jeddah City through the period from February to October 2018, nine visits for two types of natural cheese. Results showed that the total bacterial counts (CFU/ml) from Domiaty cheese from two markets (M and P) were 0.1 x 105, 8 x 105 and 1 x 10 5 CFU/ml respectively (3 visits of M market) and 4 x 106, 0.4 x 106, 6.5 x 103, 1 x 103, 0.1 x 103 and 0.1 x 103 CFU/ml respectively (six samples from 6 visits from P market). Results showed that the total bacterial counts (CFU/ml) from Hungarian cheese were 1.5 x 10 5, 1x 10 4, 11 x 10 4 and 4 x10 6 CFU/ml respectively from (4 visits of M market) and 0.18 x 104, 3 x 106, 22 x 106, 6 x 106 and 5 x 104 CFU/ml respectively (5 visits from P market).Different bacterial isolates from cheese were identified by morphology and biochemical test. Bacterial isolates from cheeses were identified by VITEK MS as follow: Serratia liquefaciens (D6-1, D6-2, D14-1, D13-1 and D13-2), and Pseudomonas fluorescens (D14-2) were isolated from Domiaty cheese while Enterococcus faecium (H11-2), Serratia liquefaciens (H15-1) and Streptococcus thermophilus (H14-1) were isolated from Hungarian cheese. Some selected bacterial isolates were identified by 16S rRNA. Isolates were belong to MK757978 (Raoultilla terrigena (D15-1)), MK757979 (Bacillus cereus (D16-1)), MK757980 (Enterococcus faecalis (H10-2)), MK757982 (Enterococcus fiscalism (H11-1)), MK757981 (Serratia liquefactions (H13-1)), MK757984 (Anoxybacillus flavithermus (H17-1). All bacterial isolates have been tested for the formation of biofilm using a Tissue Culture Plate (TCP). Results revealed 12.5% and 46.15% of high biofilm formation respectively for bacterial isolates of Domiaty and Hungarian cheeses.