Key points are not available for this paper at this time.
Rhododendron arboreum (Ericaceae) is an evergreen shrub, predominantly present in the Himalayas, and used traditionally for various ailments. The present study was focused on using the bioassay-guided method to identify the active fractions with phytochemical analysis and validated for antimicrobial activity against drug-resistant strains through in silico analysis. Crude extract and three fractions were prepared, namely ethyl acetate fraction, hexane fraction, and chloroform fraction, and were screened against standard cultures Escherichia coli 25922, Staphylococcus epidermidis 35984, Klebsiella pneumoniae BAA-1705 and drug-resistant cultures. The most active fraction, ethyl acetate, was phytochemically screened, both qualitative and quantitative, thin layer chromatography, Gas Chromatography-Mass Spectrometry (GC/MS) analysis, and the compounds identified were further subjected to in silico analysis. The antibacterial studies showed that ethyl acetate fraction was most active against the standard of cultures as well as drug-resistant isolates at the concentration of 1.25 mg/ml for E. coli standard culture and drug-resistant culture, whereas for drug-resistant Staphylococcus aureus higher concentration of 5 mg/ml was effective. Thin-layer chromatography showed the presence of three subfractions in the ethyl acetate fraction which were further analyzed by GC/MS. The combined analysis of GC/MS and in silico studies showed that strychane, 1-acetyl-20. alpha-hydroxy-16-methylene to be the most potent anti-microbial compound with the lowest binding energy −5.22 kcal/mol exhibiting one hydrogen bond of bond length of 2.67. Hence, based on the present findings, it might be summarised that the ethyl acetate fraction possesses compounds with the potential to resist drug resistance.
Rynjah et al. (Fri,) studied this question.