Ika Rahmatul Layly, Hanif Fikri, Aji Sutrisno, Catur Sriherwanto, Fahmi Achmad Saputra, Indria Puti Mustika
Plant oils are typically converted into fatty acid methyl esters in biodiesel production using alcohol and chemical catalysts (KOH or NaOH). These catalysts harm the environment and are inefficient with oils high in free fatty acids. Thus, lipase enzymes have been developed as catalysts for transesterification, including esterification, transesterification, aminolysis, and lactonization. This study aims to obtain lipase enzymes for converting plant oils into biodiesel. Microorganisms were isolated, screened, and identified from palm oil mill effluent. The selected isolates were optimised for growth in Luria Bertani medium using the one-factor at a time method. The crude lipase enzyme was characterised for optimal temperature, pH, stability, and activator and inhibitor effects. The molecular weight was determined using SDS-PAGE and zymography. The lipase was then applied to enzymatic biodiesel production, with descriptive and qualitative data analysis. In this study, 65 strains were isolated from POME samples, identifying 5 with the highest lipase activity as Enterobacter cloacae. The lipase from E. cloacae showed optimal activity at pH 7 and 30 °C, with an active molecular weight of 21.38 kDa. Fe3+, Mn2+, Zn2+ ions, b-mercaptoethanol, acetone, and SDS enhanced enzyme activity, while Mg2+ ions, Tween 80, and Triton X-100. E. cloacae lipase converted plant oil to biodiesel with a yield of 96.91%. © 2026 Informa UK Limited, trading as Taylor & Francis Group.
Research Center for Applied Microbiology, National Research and Innovation Agency, West Java, Bogor, Indonesia; Faculty of Agricultural Technology, Brawijaya University, East Java, Malang, Indonesia
