GC-MS profiling and activity of Diospyros melanoxylon leaves against nosocomial pathogens

The rising incidence of microbial resistance and disorders associated with oxidative stress has propelled the quest for natural substances with therapeutic efficacy. The plant Diospyros melanoxylon (Roxb) known as tendu in Hindi & kendu in Odia, is indigenous to India (Odisha, Chhattisgarh, Jharkhand), Sri Lanka, Bangladesh and is a member of the Ebenaceae family. The current study is a chemometric analysis and antimicrobial study of D. melanoxylon leaf extract against some microorganisms responsible for hospital-acquired infections. Gas chromatography and Mass Spectroscopy (GC-MS) analysis was done to identify the phytocompounds present in the plant. The content of tannin, flavonoids and phenolics in D. melanoxylon was established using a colorimetric assay. Antioxidant activity was studied by assessing free radical scavenging assays. The in vitro antimicrobial assay was conducted using viable cell count and the turbidimetric method. The GC-MS analysis confirms the presence of various phytoconstituents like Epoxylanistan-11-ol, Phenol,2,4-bis(1,1-dimethylethyl)-,Ur-12-2n-24-oic acid, α-amyrin & trimethylsilyl with α-amyrin being found to major constituent responsible for the pharmacological properties. The result indicated that ethyl acetate extract of D. melanoxylon leaves exhibited remarkable phenolic, flavonoid and tannin content. The plant extract has been effective against Gram-negative bacteria that cause hospital-acquired infections following liver transplantation, such as Acinetobacter baumannii, Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and Pseudomonas aeruginosa. These findings may be crucial in the development of new plant antibiotics against bacterial infections that predominantly happen following hospitalisation after liver transplantation. Further research should explore its mechanism of action, isolation and possible application in combination therapy.