Study of antibacterial, anti-proliferative and pro-apoptotic potential of the cell extracts of endophytic fungi and bacteria isolated from Pajanelia longifolia (Willd.) K. Schuman

Abstract

Endophytes contribute to the synthesis of significant metabolites in symbiotic association with their host plants. On considering the medicinal importance of the prominent tree species Pajanelia longifolia (Willd.) K. Schuman, the study was conducted to isolate and identify the endophytic bacteria and fungi for their bioactivity. The isolation of endophytic bacteria and fungi were performed by surface sterilisation of the stem and leaf samples of P. longifolia. The obtained bacterial and fungal endophytic isolates were maintained in nutrient agar and Potato Dextrose Agar (PDA) media and were examined for colony morphology and microscopic appearances with varied biochemical characterisations. Furthermore, both the fungal and bacterial isolates were subjected to solvent extractions to evaluate antibacterial activity. Also, anti-proliferative effects due to apoptotic induction by the endophytic fungal extracts were checked against proliferative yeast cells. Moreover, endophytic bacteria belonging to Enterococcaceae had shown antibacterial activity against Salmonella species. In the present study, fungal species belonging to Cladosporium predominantly found to inhabit as endophytic fungi in the plant samples. Also, this particular fungus among other selected endophytic fungi attributed to causing effective anti-proliferative activity. The endophytic bacteria belonging to Enterococcus and Micrococcus genera showed significant antimicrobial activity against Salmonella typhimurium (ATCC 23564).