An endophytic fungus associated with Kayea assamica (King & Prain): A study on its molecular phylogenetics and natural products

Abstract

Endophytes; a ubiquitous group of microorganisms considered as a gem box of bioactive constituents of medical significance. Studies on this emerging field is very less among the research communities. The present study focused on the molecular phylogenetics of the endophytic fungus that associated with the leaf of Kayea assamica, an endemic plant species of Northeast India and identification of its secondary metabolites (natural product) that produced under in vitro condition. The endogenous fungus was isolated from the sterile disease-free leaf segment (1 cm), followed by PCR amplification of ITS region using the extracted genomic DNA as a template. Further, the crude methanol extract of the fungal culture was subjected to Gas Chromatography-Mass Spectrometry (GC–MS) analysis. The molecular phylogenetic analysis confirmed the fungal isolate as Beltraniella species (endophyte). The ITS sequence was submitted to GenBank database (Id MH295767.1). The GC-MS analysis revealed eleven different secondary metabolites at different retention times. Many of these compounds have been reported to be plant & endophytic metabolite, essential oil component, recognized fragrant molecule, antimicrobial, antioxidant, anticancer activities etc. The findings projected that the endophyte may have a significant role in the host-defense mechanism. Tetrapentacontane is a part of fragrant molecules found in juvenile agarwood shown highest abundance (54.63%) at 21.477 RT followed by the others. This study performed for the first time on endosymbiotic microorganism present in the respective plant species and highlighted this endophytic fungus as a unique source of non-plant based bioactive compounds with future biotechnological consequence.