Potensi Bakteri Asam Laktat yang Diisolasi dari Nira Aren dalam Menghambat Pertumbuhan Bakteri Patogen Asal Pangan

POTENSI BAKTERI ASAM LAKTAT YANG DIISOLASI DARI NIRA
AREN DALAM MENGHAMBAT PERTUMBUHAN BAKTERI
PATOGEN ASAL PANGAN

ABSTRAK

Nira diketahui mengandung gula dan komponen nutrisi lain yang baik bagi
pertumbuhan mikroorganisme, salah satunya bakteri asam laktat. Tujuan dari
penelitian ini adalah untuk mendapatkan isolat bakteri asam laktat potensial dari
nira aren yang mampu menghambat pertumbuhan bakteri patogen asal pangan
dan memenuhi syarat lain sebagai probiotik. Pada berbagai interval waktu
fermentasi (0, 12, 24, 36 dan 48 jam) nira aren, didapatkan isolat bakteri asam
laktat yang tumbuh pada media de mann Rogosa agar (MRSA) + CaCO3 1%.
Masing-masing isolat diuji kemampuannya menghambat bakteri patogen asal
pangan (Salmonella typhi, Staphylococcus aureus dan Escherichia coli) pada
media Mueller Hinton Agar (MHA) dengan metode difusi cakram. Isolat yang
potensial diuji kemampuannya bertahan pada suasana saluran pencernaan seperti
pada pH lambung (2.0), pH usus (7.2), garam empedu (0.5% ox gall) dan mampu
membentuk biofilm pada permukaan padat stainless steel pada media MRSA.
Hasil isolasi bakteri asam laktat asal nira aren didapat 16 isolat yang tumbuh pada
media MRSA + CaCO3 1% dan didominasi oleh bakteri heterofermentatif. Hanya

ada 6 isolat (MF5, MF10, MF11, MF13, MF14 dan MF15) potensial yang mampu
menghambat pertumbuhan bakteri patogen asal pangan dan mampu memproduksi
senyawa antimikroba selain asam-asam organik. Dari 6 isolat BAL potensial
didapat 5 isolat yang mampu bertahan pada suasana saluran pencernaan dan
mampu menempel pada permukaan padat stainless steel yaitu MF5, MF10, MF11,
MF14 dan MF15, sedangkan isolat MF13 tidak mampu bertahan pada suasana
garam empedu. Namun, ada dua isolat BAL paling potensial dari semua
parameter uji yaitu MF11 dan MF14.
Kata Kunci: Antimikroba, Bakteri Asam Laktat, Probiotik

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Universitas Sumatera Utara

POTENCY of LACTIC ACID BACTERIA ISOLATED of PALM JUICE in
INHIBITING PATHOGENIC BACTERIA in FOOD

ABSTRACT

Nira contain sugar and other nutritional components that are good for the growth
of microorganisms, one of which lactic acid bacteria. The purpose of this study

was to obtain lactic acid bacteria isolates potential of palm juice that could inhibit
the growth of pathogenic bacteria of food origin and included in the candidate
probiotics. Fermentation at various time intervals (0, 12, 24, 36 and 48 hours)
palm juice, obtained LAB isolates were grown on media de mann rogosa agar
(MRSA) + 1% CaCO3. Each of LAB isolates tested for their ability to inhibit
pathogenic bacteria origin of food (Salmonella typhi, Staphylococcus aureus and
Escherichia coli) on media Mueller Hinton Agar (MHA) with disc diffusion
method. Isolates potential was inhibited pathogenic bacteria origin of food tested
for its ability to survive in the atmosphere of the gastrointestinal tract such as
gastric pH (2.0), intestinal pH (7.2), bile salts (0.5% ox gall) and capable of
forming a biofilm on the surface of solid stainless steel on media MRSA ,origin
isolated palm juice obtained 16 isolates of Lactic acid bacteria are grown on
media MRSA CaCO3 + 1% and is dominated by heterofermentatif bacteria. There
were only 6 isolates (MF5, MF10, MF11, MF13, MF14 and MF15) capable
potentially inhibited the growth of pathogenic bacteria of food origin and isolates
were also able to produce antimicrobial compounds other than organic acids.
Only 5 out of 6 isolates that were able to survive in the atmosphere of the
gastrointestinal tract and is able to form a biofilm on the surface of solid stainless
steel namely MF5, MF10, MF11, MF14 and MF15, while isolates MF13 are not able
to survive in an atmosphere of bile salts that are removed from the isolates

candidates probiotics From all of isolates, there were two the most potentially
isolates as a probiotic candidate namely MF14 and MF11.
Keywords: Lactic Acid Bacteria, Probiotics, Antimicrobial

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Universitas Sumatera Utara