Isolasi dan Karakterisasi Bakteri Pendegradasi Limbah Minyak Pelumas Berdasarkan Aktivitas Biosurfaktan

Abstract

Limbah minyak pelumas merupakan limbah berbahaya yang mengandung senyawa toksik seperti polycyclic aromatic hydrocarbon (PAH) dan logam berat. Bioremediasi menggunakan bakteri pendegradasi hidrokarbon merupakan pendekatan yang potensial untuk mengatasi pencemaran tersebut. Penelitian ini bertujuan mengisolasi dan mengkarakterisasi bakteri dari limbah minyak pelumas PT Angkasa Tunggal Selaras Nugratama, serta menyeleksi isolat potensial berdasarkan aktivitas biosurfaktan. Isolasi dilakukan dari sampel campuran dan sampel minyak, kemudian karakter makroskopis dan mikroskopis koloni diamati. Seleksi biosurfaktan dilakukan melalui oil spreading test dan uji emulsifikasi (E24) dengan variasi konsentrasi limbah minyak 0, 100, 200, dan 400 ppm. Hasil penelitian menunjukkan bahwa diperoleh 14 isolat bakteri, terdiri atas 10 isolat dari sampel campuran dan 4 isolat dari sampel minyak. Isolat M5 100 ppm, M1 200 ppm, dan M2 400 ppm (50,27%; 45,78%; dan 45,20%) menunjukkan aktivitas biosurfaktan yang tinggi berdasarkan uji emulsifikasi. Karakteristik fisiologis melalui uji biokimia menunjukkan bahwa isolat M5, M1, dan M2 berturut-turut memiliki kedekatan dengan karakter fisiologis genus Bacillus, Lactobacillus, dan Pseudomonas. Ketiga genus ini diketahui memiliki kemampuan dalam produksi biosurfaktan dan berpotensi dikembangkan sebagai agen bioremediasi limbah minyak pelumas.

Lubricating oil waste is a hazardous waste containing toxic compounds such as polycyclic aromatic hydrocarbons (PAHs) and heavy metals. Bioremediation using hydrocarbon-degrading bacteria is a promising approach to addressing this pollution. This study aimed to isolate and characterise bacteria from the lubricating oil waste of PT Angkasa Tunggal Selaras Nugratama, and to select potential isolates based on their biosurfactant activity. Isolation was carried out from mixed oil samples, after which the macroscopic and microscopic characteristics of the colonies were observed. Biosurfactant selection was carried out via an oil spreading test and an emulsification test (E24) with waste oil concentrations at 0, 100, 200 and 400 ppm. The results showed that 14 bacterial isolates were obtained, comprising 10 isolates from the mixed samples and 4 isolates from the oil samples. Isolates M5 (100 ppm), M1 (200 ppm) and M2 (400 ppm) (50,27%; 45,78%; and 45,20%) exhibited high biosurfactant activity based on the emulsification test. Physiological characteristics determined by biochemical tests showed that isolates M5, M1 and M2 were, respectively, closely related to the genera Bacillus, Lactobacillus and Pseudomonas. These three genera are known to produce biosurfactants and have the potential to be developed as bioremediation agents for lubricating oil waste.