Culture-Dependent Isolation and Characterization of Lignocellulose Degrading Bacteria from the Gut of Mole Crickets

Abstract

Background: Lignocellulose, composed of cellulose, hemicellulose, and lignin, forms the main structural component of plant biomass and represents a major renewable resource for bioenergy and bio-based products. Its biodegradation is mediated by diverse microbial communities possessing carbohydrate-active enzymes (CAZymes). The gut microbiota of soil-dwelling insects such as mole crickets (Gryllotalpidae) offers a specialized environment rich in lignocellulolytic microorganisms with potential applications in biotechnology and sustainable agriculture. Objective: This study aimed to isolate and characterize lignocellulose-degrading bacteria from the gut of mole crickets. Materials and Methods: Male and female grass- and mushroom-feeding mole crickets were manually collected from a farm in Major Porter (Leng) village, Barkin Ladi Local Government Area, Plateau State, Nigeria. The insects were surface sterilized, dissected aseptically, and the gut contents homogenized and serially diluted. Bacteriological and biochemical analyses were carried out to identify lignocellulose-degrading bacteria. Molecular characterization was performed using PCR amplification of 16S rRNA and gyrB genes, followed by sequencing and phylogenetic analysis to determine bacterial identity and relatedness. Results: Five lignocellulose-degrading bacterial isolates were successfully obtained from male and female mole crickets. The isolates exhibited significant enzymatic potential for lignocellulose breakdown. Molecular and phylogenetic analyses confirmed the distinct identities and relationships among the isolates, demonstrating diverse lignocellulolytic capacities. Conclusion: The gut bacteria of mole crickets possess strong lignocellulose-degrading abilities and can serve as effective bioinoculants to enhance soil organic matter decomposition, improve fertility, and reduce fertilizer dependency. These findings highlight their potential in biotechnological and sustainable agricultural applications.