Seleksi Material Penempelan Biofilm Isolat Bakteri Resisten Tembaga asal PT. Freeport Indonesia

Abstrak

ABSTRAK Bakteri yang mampu tumbuh pada lingkungan tercemar logam berat cenderung membentuk biofilm. Biofilm terdiri dari berbagai kelompok bakteri yang tumbuh bersama mikroba lain yang diselubungi matriks polimer ekstraseluler (EPS) dan melekat pada permukaan materi organik maupun anorganik. Empat isolat bakteri yang digunakan dalam penelitian ini adalah bakteri resisten tembaga yang diisolasi dari tailing PT Freeport Indonesia, Timika, Papua. Pada penelitian ini dilakukan seleksi materi penempelan biofilm berupa materi organik maupun anorganik untuk memperoleh materi penempelan yang optimal untuk pertumbuhan biofilm. Masing- masing isolat diinokulasikan ke dalam medium LB yang mengandung 100 mg/L CuSO4. Material uji digantung pada tutup erlenmeyer, diinkubasi pada shaker inkubator dengan kecepatan 100 rpm, selama 2 minggu pada suhu ruang. Aktivitas pembentukan biofilm diamati setiap minggu sekali berdasarkan penempelan biofilm pada material yang diamati di bawah mikroskop. Pembentukan massa biofilm diukur dengan cara menimbang material penempelan sebelum dan sesudah penempelan biofilm. Empat isolat dapat tumbuh dengan baik pada batu kali, kayu, plastik LLDPE dan plastik PET namun penempelan biofilm lebih stabil pada potongan kayu dan batu kali. Pseudomonas aeuruginosa strain C53 menunjukkan kemampuan paling tinggi dalam pembentukan biofilm kemudian diikuti Bacillus cereus strain C38, Lycinibacillus fusiformis strain C40 dan Bacillus subtilis strain C43. Kata Kunci: Bakteri Resisten tembaga, Biofilm, Material Penempelan. ABSTRACTBacteria capable of growing in a heavy-metal polluted environment tend to form biofilm. Biofilm consists of various groups of bacteria that grow together with other microbes that are surrounded by the extracellular polymeric substance (EPS) and adhere to the surface of both organic and inorganic matter. Four bacterial isolates used in this study were copper-resistant bacteria isolated from PT Freeport Indonesia's tailings, Timika, Papua. In this research, selection of biofilm attachment material was conducted in the form of organic or inorganic material to obtain optimal attachment material for biofilm growth. Each isolate was inoculated into LB medium containing 100 mg/L CuSO4. The test material was suspended on the erlenmeyer cover, incubated in the incubator shaker with 100 rpm, for 2 weeks at room temperature. The biofilm forming activity was observed weekly based on the attachment of biofilms to the material observed under the microscope. To determine the mass of the biofilm formed, calculation of the attachment material weight was done before and after the biofilm attachment. Four isolates could grow well on stone, wood, LLDPE plastic and PET plastic. However, the biofilm attachment looked more stable on wood and stone fragments. The highest ability in the biofilim formation was performed by Pseudomonas aeuruginosa strain C53, followed by Bacillus cereus strain C38, Lycinibacillus fusiformis strain C40 and Bacillus subtilis strain C43. Keywords: Copper Resistant Bacteria, Biofilm, Attachment Material