Karakterisasi dan Uji Aktivitas Aktinomisetes Penghasil Antibiotik terhadap Multi-Drug Resistant Bacteria Strains
Ahmad Ikhsanudin, Dr. Endah Retnaningrum, M.Eng.
2023 | Tesis | S2 Biologi
Peningkatan resistensi bakteri patogen terhadap berbagai jenis antibiotik menjadi salah satu permasalahan dalam dunia kesehatan. Penelitian ini bertujuan untuk mengetahui kemelimpahan dan keragaman aktinomisetes yang ada di hutan mangrove, Baros, DIY, mengetahui aktivitas antibiotik, identifikasi isolat penghasil antibiotik berdasarkan karakterisasi kultural, morfologis, fisiologis, biokimiawi, dan molekuler serta mendeteksi keberadaan gen pengkode antibiotik. Beberapa tahapan dalam penelitian ini meliputi: 1) Sampling rizosfer mangrove dan pengukuran parameter lingkungan; 2) Isolasi dan purifikasi aktinomisetes; 3) Skrining isolat penghasil antibiotik; 4) Karakterisasi kultural, morfologis, fisiologis, dan biokimiawi; 5) Karakterisasi molekuler gen 16S rRNA 6) Produksi dan ekstrasi antibiotik isolat terpilih dan 7) Uji MIC terhadap lima strain bakteri MDR. Hasil penelitian menunjukkan, kemelimpahan paling tinggi ditemukan pada rizosfer tipe lumpur terendam yaitu 2,16 x 104 cfu/g. Isolat yang dimurnikan sebanyak 15 isolat yang memiliki keragaman tinggi dari warna miselium aerial, miselium substrat, dan pigmen yang diproduksi. Lima isolat diantaranya mampu menghasilkan antibiotik. Isolat terpilih yang memiliki rata-rata zona hambat tertinggi, 42,5 mm yaitu isolat ACSAN21-05. Isolat ACSAN21-05 memiliki tipe rantai spora polysporus dengan tipe percabangan hifa aerial rectiflexibiles, tumbuh optimum pada suhu 30oC, salinitas 1%, pH 7, mampu menghidrolisis pati, menguraikan H2O2, serta menggumpalkan susu dan menguraikannya menjadi kasein. Berdasarkan gen 16S rRNA, isolat ACSAN21-05 tergolong ke dalam genus Streptomyces. Crude extract isolat ACSAN21-05 mampu menghambat E. coli dan E. cloacae dengan nilai MIC masing-masing 25 dan 50 mg/mL.
Increasing the resistance of
pathogenic bacteria to various types of antibiotics is one of the problems in
the world of health. This study aims to determine the abundance and diversity
of actinomycetes in mangrove forests, Baros, DIY, to determine antibiotic
activity, to identify antibiotic-producing isolates based on cultural,
morphological, physiological, biochemical, and molecular characteristics, and
to detect the presence of antibiotic coding genes. Several stages in this study
include: 1) Sampling the mangrove rhizosphere and measuring environmental
parameters; 2) Isolation and purification of actinomycetes; 3) Screening of
isolates producing antibiotics; 4) Cultural, morphological, physiological, and
biochemical characterization; 5) Molecular characterization of the 16S rRNA
gene 6) Production and extraction of selected isolate antibiotics and 7) MIC
test on five strains of MDR bacteria. The results showed that the highest
abundance was found in the submerged mud-type rhizosphere, namely 2.16 x 104
cfu/g. There were 15 purified isolates that had high diversity in the color of
aerial mycelium, substrate mycelium, and the pigments produced. Five isolates
of them could produce antibiotics. The selected isolate with the highest
average inhibition zone, 42.5 mm, is isolated ACSAN21-05. ACSAN21-05 isolate
has polysporus spore chain type with aerial rectiflexibles hyphae branching
type, optimum growth at 30oC, 1% salinity, pH 7, able to hydrolyze
starch, decompose H2O2, and coagulate milk and decompose
it into casein. Based on the 16S rRNA gene, isolate ACSAN21-05 belongs to the
genus Streptomyces. Crude extract isolate ACSAN21-05 was able to inhibit
E. coli and E. cloacae with MIC values of 25 and 50 mg/mL,
respectively.
Kata Kunci : Aktinomisetes, rizosfer, mangrove, antibiotik, MDR
