Isolation and Identification of Lipase‐Producing Bacteria From Sewage Sediment and Their Crude Lipase Applications in Biodiesel and Nanoparticle Production

ABSTRACT

This study employed tributyrin agar to isolate and detect lipase‐producing bacteria from soil polluted with waste cooking oil in Bhubaneswar, Odisha. 16S rRNA sequencing and phylogenetic analysis identified the potent lipase‐producing Gram‐negative isolate as Acinetobacter junii (Accession number: PZ528661), showing lipase activity (0.208 ± 0.05 µmol/min). Transesterification of used cooking oil was carried out using crude lipase to produce biodiesel, as gas chromatography–mass spectrometry (GC‐MS) analysis identified transesterification markers in the fatty acid ethyl esters (FAEEs). It was evident from the Fourier transform infrared spectroscopy (FTIR), Ultraviolet–visible (UV‐Vis) spectroscopy, scanning electron microscope (SEM), and x‐ray diffraction (XRD) that the same lipase was used to greenly synthesize zinc oxide nanoparticles (ZnO NPs). Because these nanoparticles showed strong antibacterial and anti‐biofilm activity against A. junii (Accession number: PZ528661), they have the potential to be used in a biological application. The results indicate the industrial and environmental potential of bacterial lipase in displaying its dual applications in nanotechnology and generating biodiesel.