ISOLASI, KARAKTERISASI, DAN IDENTIFIKASI BAKTERI ASAM LAKTAT DENGAN AKTIVITAS ANTI JAMUR DARI MAKANAN TRADISIONAL TERFERMENTASI

REZCHA INDRIATI Y, Prof. Drs. Langkah Sembiring, M.Sc., Ph.D.

2014 | Skripsi | BIOLOGI

Bakteri asam laktat (BAL) yang berpotensi memiliki aktivitas anti jamur telah diisolasi dari makanan tradisional terfermentasi. Seberat 5 gram sampel makanan tradisional terfermentasi dihomogenasi dengan 45 ml larutan pepton dengan menggunakan blender. Suspensi diinokulasikan secara streak plate pada medium MRSA yang disuplementasi dengan CaCO3. Isolat yang diduga sebagai BAL diseleksi kemampuan anti jamurnya dengan menggunakan metode overlay dengan medium MEA soft mengandung spora kapang (Aspergillus flavus FNCC 6002, A. parasiticus FNCC 6033, dan Penicillium citrinum FNCC 6111) dan metode difusi agar. Lima isolat dengan aktivitas tertinggi selanjutnya diuji dengan menggunakan metode perhitungan biomassa kapang. Satu isolat dengan aktivitas tertinggi selanjutnya dikarakterisasi dan diidentifikasi dengan menggunakan kit API 50 CHL. Diperoleh 28 isolat BAL dari 5 jenis sampel (mocaf, gatot, tiwul, tempe kara benguk dan tempe kedelai). Pengujian aktivitas anti jamur dengan menggunakan metode overlay dan difusi agar menghasilkan 27 isolat yang mampu melakukan penghambatan pada pertumbuhan kapang. Sebanyak 5 isolat dengan aktivitas anti jamur tertinggi yaitu isolat G7 dari gatot, K1 dari tempe kedelai, M1 dan M6 dari mocaf, serta T9 dari tiwul dipilih untuk diuji menggunakan metode perhitungan biomassa. Isolat G7 mampu menurunkan sebesar 63,17% biomassa kapang, diikuti isolat M6 sebesar 62,32%; M10 sebesar 59,13%; T9 sebesar 51,65%; dan K1 sebesar 41,15%. Isolat G7 dipilih untuk dikarakterisasi dan diidentifikasi. Berdasarkan karakteristik morfologi koloni dan sel, serta hasil identifikasi dengan kit API 50 CHL, isolat G7 diketahui sebagai salah satu strain Lactobacillus plantarum dengan persentase kemiripan 99,3%. Dengan demikian, disimpulkan bahwa isolat BAL L. Plantarum G7 yang diisolasi dari gatot mempunyai aktivitas anti jamur dengan menghambat pertumbuhan kapang.

A lactic acid bacteria (LAB) that has a potential antifungal activity was isolated from traditional fermented foods. Five grams of each traditional fermented food samples were homogenized with 45 ml of peptone solution using a blender. The suspension were inoculated using streak plate method on MRSA medium supplemented with CaCO3. Suspected isolates as LAB was selected for antifungal ability using overlay method on MEA soft medium containing mold spores (Aspergillus flavus FNCC 6002, A. parasiticus FNCC 6033, and Penicillium citrinum FNCC 6111) and agar diffusion method. Five isolates with the highest activity were tested using calculation mold biomass testing. An isolate with the highest activity was characterized and identified using API 50 CHL kit. Twenty eight LAB isolates were obtained from 5 samples (mocaf, gatot, tiwul, kara benguk tempeh and soybean tempeh). Then the antifungal activity was examined further using overlay test and agar diffusion method to produce 27 LAB isolates that were able to perform fungal growth inhibition. Five isolates with the highest antifungal activity were G7 isolate from gatot, K1 from soybean tempeh, M1 and M6 from mocaf, and T9 from tiwul. These isolates were selected to be tested using calculation mold biomass method. The G7 isolate was able to reduce 63,17% amount of mold biomass, followed by M6 was 62,32%; M10 was 59,13%; T9 was 51,65%; and K1 was 41,15%. Therefore, G7 isolate was selected to be characterized and identified further. Based on colonial and cell morphological characteristics and identification results of API 50 CHL kit, G7 isolate was known as a member of Lactobacillus plantarum strain with 99,3% similarity. Thus concluded that LAB which is L. Plantarum G7 that was isolated from gatot has antifungal activity to inhibit fungal growth

Kata Kunci : : bakteri asam laktat, gatot, anti jamur, kit API 50 CHL