PRELIMINARY SCREENING OF PROBIOTICS CHARACTERISTICS OF BACTERIA ISOLATED FROM DIFFERENT KIND OF DOMESTIC CHEESE

Probiotics are beneficial bacteria that contribute to the health and balance of the intestinal tract. In people, the most common way to prevent from getting any infectious disease or digestive upset is by using vaccines and antibiotics. Besides that, naturally occurring microflora is a good alternative to protect the host gut. In developing a good strain of probiotics, there are a few criteria to be achieved by the bacteria such as ability to tolerate acidic condition and survival in the presence of bile salts. All isolates were grown 24 hours in Man Rogosa and Sharp (MRS). Acid tolerance test was done by incubating the isolates into Phosphate Buffered Saline (PBS) in pH 2, and 3 for 3 hours. For the bile salts test, the isolates were exposed to the bile salts for 4 hours. At each hour, the optical density (OD) of the isolates was measured. For both test, the cells survival in these two conditions was measured by OD after incubation on new fresh MRS. From 12 isolates, 6 isolates are acid tolerate while 5 isolates are able to survive in p