Lactic Acid Bacteria Isolated from Meat with Acid and Bile Salt Tolerance as Probiotics Candidate by in vitro Technique

Abstract

Lactic acid bacteria have been reported to be useful as a health adjunct and are commonly added to food as delivery mechanism. As candidate for probiotic, lactic acid bacteria should have the ability to survive in the digestion process such as resistance towards gastrointestinal tract pH and bile salt concentrations. Lactic acid bacteria utilised in this research were isolated from meat. Twenty eight isolates of lactic acid bacteria selected for their resistancy towards gastric juice pH (pH 2,0) and small intestines pH (pH 7,2) with 0,3% bile salt under in vitro conditions. The result showed that all strains well grown in small intestines pH (pH 7,2), but only 10 isolates had good resistance to gastric juice pH. There were significant difference among theme (P<0,05). Bile salt 0,3% with pH 7,2 influenced significantly the growth of lactic acid bacteria selected at gastric juice condition showed that only three strains (1A5, 2B4, and 1B1) showed tolerance (P<0,05) could be used as probiotics candidate in further applications.

Bakteri asam laktat merupakan mikroflora normal daging sehingga lebih sesuai bila dijadikan kultur starter untuk pengolahan produk fermentasi yang berasal dari daging. Syarat utama suatu isolat berpotensi sebagai probiotik adalah memiliki toleransi yang tinggi terhadap asam lambung dan garam empedu dalam saluran pencernaan. Kondisi kritikal yang harus dihadapi bakteri probiotik dalam saluran pencernaan manusia dimulai dari lambung, yaitu bakteri harus mampu bertahan terhadap pH yang sangat rendah (pH 2,0) selama minimal 90 menit. Bakteri probiotik selanjutnya memasuki saluran usus bagian atas (pH 7,2) yang merupakan tempat disekresikan garam empedu. Penelitian ini bertujuan untuk melakukan seleksi bakteri asam laktat hasil isolasi dari daging sapi dari pasar tradisional di kabupaten Bogor (Arief et al., 2006) untuk mendapatkan kandidat isolat probiotik yang mempunyai karakteristik pertumbuhan terbaik dalam kondisi lingkungan asam kuat HCl sesuai dalam lambung dan adanya garam empedu (0,3%) sesuai usus halus.