Metabolite fingerprinting, in vitro antimicrobial and antioxidant activities and in-silico docking in Alloteropsis cimicina and its endophytic fungus Penicillium pinophilum

Endophytic fungal interaction with medicinal plant resulting in the production of bioactive compounds influenced the present study. Endophytic fungus Penicillium pinophilum Hedgc. from Alloteropsis cimicina with high incidence was isolated by incubation methods and characterized by morphological and molecular (ITS rDNA region) methods. Penicillium pinophilum was cultured on PD broth and metabolites of host and endophyte were extracted with ethyl acetate and methanol. Metabolites were assayed for antimicrobial potential by well diffusion and scavenging ability by spectrophotometric and electrochemical methods. Metabolite profiling by Orbitrap High-Resolution Liquid Chromatography-Mass Spectrometry and Fourier-transform infrared spectroscopy and by validation of antimicrobial and antioxidant activities in-silico drug-likeness of spectral compound prediction and molecular docking were performed. Host and P. pinophilum extracts showed strong antimicrobial potential against certain clinical bacterial strains and Fusarium oxysporum. Fungal extracts exhibited higher antioxidant activity than A. cimicina extract. Metabolite profiling indicated 14 and 21 antimicrobial, 10 and 13 antioxidant compounds in A. cimicina and P. pinophilum extracts, respectively. There were eight spectral compounds common to endophyte and host with high binding affinity towards receptors. The present study revealed that P. pinophilum and A. cimicina are natural reservoirs of novel bioactive compounds with antimicrobial and antioxidant properties. Graphic Abstract