Molecular Characterization of Fungal Communities Associated with Postharvest Spoilage of Irvingia gabonensis Fruits and Seeds

Abstract

Irvingia gabonensis is an economically important fruit tree native to the tropical rainforest regions of West and Central Africa. However, microbial infestation during postharvest storage significantly threatens its quality; safety; and shelf life. This study aimed to identify and molecularly characterize fungal pathogens associated with postharvest spoilage of I. gabonensis fruits and seeds. Fruits and seeds of I. gabonensis were obtained from Sagana Market (Mile 1) and Creek Road Market in Port Harcourt; Rivers State; Nigeria. Fungi were isolated and purified on potato dextrose agar (PDA). Genomic DNA was extracted from pure cultures using the ZymoBIOMICS DNA MicroPrep Kit. Polymerase chain reaction (PCR) amplification of the internal transcribed spacer (ITS) region was performed; and amplicons were sequenced using the Sanger sequencing method. The obtained sequences were aligned and compared with reference sequences in the National Center for Biotechnology Information (NCBI) database. Phylogenetic analysis was conducted to determine genetic relationships.Phylogenetic analysis revealed eight distinct fungal strains associated with postharvest deterioration of I. gabonensis. The seed samples yielded Aspergillus awomori (JTF1); Penicillium choerospondiatis (JTF2); Talaromyces pinophilus (JTF3); Trametes polyzona (JTF4); Aspergillus flavus (JTF5); and Lentinus squarrosulus (JTF6). The fruit samples yielded Penicillium citrinum (JTF7) and Trametes polyzona (JTF8). The findings demonstrate that I. gabonensis fruits and seeds harbor diverse fungal pathogens that may contribute to postharvest spoilage. Their presence raises concerns regarding food safety and potential public health risks associated with consumption.