Screening, lipA Gene Amplification and Molecular Identification of Lipolytic Fungi from Contaminated Soils

Abstract

Lipase is a glycerol ester hydrolase that hydrolyzes esters of triglycerides. This study aimed to isolate, screen and characterize lipolytic fungi with lipA gene from soil environments. Fungi [molds and yeasts] were isolated from contaminated soil samples randomly collected from Palm oil mills, Abattoirs and Automobile servicing workshops in Eleme and Obio Akpor local governments in Rivers State, Nigeria using standard microbiological techniques. Qualitative Lipase screening assay was carried out on the fungal isolates through gel diffusion assay using Tributryin, Tween 80 and Olive oil respectively. Isolates with maximum zones of clearance were selected and screened for Lipase gene for hydrolysis of triacylglyceride [lipA gene] through Lipase gene amplification and were identified by Internal Transcribed Spacer characterization. A total of 96 fungal isolates were obtained, lipolytic screening showed 57 lipolytic strains in which 21 lipolytic fungal strains were screened from contaminated soil from palm oil mills, 17 lipolytic strains from abattoirs and 19 lipolytic strains from automobile workshops respectively. Seven isolates with maximum zones of clearance showed lipA gene in their genomic DNA and were identified as Candida orthopsilosis PMS3 [Accession No: OL546803], Fusarium proliferatum PMS4 [Accession No: OL546804], Saccharomyces cerevisiae PMS8 [Accession No: OL546805], Penicillium paxilli ABS8 [Accession No: OL546799], Pichia kudriavzevii ENS1 [Accession No: OL546800] Aspergillus niger ENS3 [Accession No: OL546801] and Trichoderma viride ENS5 [Accession No: OL546802]. This study showed that soil fungi are potential producers of biotechnologically important lipase with diverse industrial applications.