Isolation, Structure Elucidation and In Silico Prediction of Potential Drug-Like Flavonoids from Onosma chitralicum Targeted towards Functionally Important Proteins of Drug-Resistant Bad Bugs

• Published in: Molecules (Basel, Switzerland) Switzerland), 2021-04, Vol.26 (7), p.2048
• Main Authors: Khan, Shakeel Ahmad, Khan, Shafi Ullah, Fozia, Ullah, Najeeb, Shah, Mohibullah, Ullah, Riaz, Ahmad, Ijaz, Alotaibi, Amal
• Format: Article
• Language: English
• Subjects: Acetic acid; Anthelmintic agents; Antibiotics; Antifungal Agents - chemistry; Antifungal Agents - pharmacology; antimicrobial activities; Antimicrobial agents; Antioxidants; Antiparasitic agents; Bacteria; Bacterial Proteins - antagonists & inhibitors; Bacterial Proteins - chemistry; Bacterial Proteins - metabolism; beta-hydroxyacyl dehydratase; Binding; Binding Sites; Boraginaceae - chemistry; Butanol; Cell membranes; Chemotherapy; Chloroform; Column chromatography; Computer Simulation; Dehydration; Drug development; Drug Evaluation, Preclinical; Drug resistance; Drug Resistance, Bacterial - drug effects; E coli; Enzymes; Ethyl acetate; Flavonoids; Flavonoids - chemistry; Flavonoids - isolation & purification; Flavonoids - pharmacology; Fluconazole; Fungi; Fungicides; Herbal medicine; Hexanes; Lanosterol; Microbial Sensitivity Tests; Molecular Docking Simulation; NMR; Nuclear magnetic resonance; Onosma; Onosma chitralicum; Phytochemicals; Plant extracts; Salmonella; Salmonella typhi - drug effects; Salmonella typhi - metabolism; SAR; Solvents; Staphylococcus aureus; Staphylococcus aureus - drug effects; Staphylococcus aureus - metabolism; Strains (organisms); Structure-Activity Relationship; Therapeutic targets; tRNA; Tyrosine-tRNA ligase
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules26072048

Admittedly, the disastrous emergence of drug resistance in prokaryotic and eukaryotic human pathogens has created an urgent need to develop novel chemotherapeutic agents. is a source of traditional medicine with cooling, laxative, and anthelmintic effects. The objective of the current research was to analyze the biological potential of and to isolate and characterize the chemical constituents of the plant. The crude extracts of the plant prepared with different solvents, such as aqueous, hexane, chloroform ethyl acetate, and butanol, were subjected to antimicrobial activities. Results corroborate that crude (methanol), EtoAc, and -C H fractions were more active against bacterial strains. Among these fractions, the EtoAc fraction was found more potent. The EtoAc fraction was the most active against the selected microbes, which was subjected to successive column chromatography, and the resultant compounds to were isolated. Different techniques, such as UV, IR, and NMR, were used to characterize the structures of the isolated compounds . All the isolated pure compounds ( - ) were tested for their antimicrobial potential. Compounds (4',8-dimethoxy-7-hydroxyisoflavone), (5,3',3-trihydroxy-7,4'-dimethoxyflavanone), and (5',7,8-trihydroxy-6,3',4'-trimethoxyflavanone) were found to be more active against and . Compound inhibited and to 10 ± 0.21 mm and 10 ± 0.45 mm, whereas compound showed inhibition to 10 ± 0.77 mm and 9 ± 0.20 mm, respectively. Compound inhibited to 6 ± 0.36 mm. Compounds and showed significant antibacterial potential, and the structure-activity relationship also justifies their binding to the bacterial enzymes, i.e., beta-hydroxyacyl dehydratase (HadAB complex) and tyrosyl-tRNA synthetase. Both bacterial enzymes are potential drug targets. Further, the isolated compounds were found to be active against the tested fungal strains. Whereas docking identified compound , the best binder to the lanosterol 14α-demethylase (an essential fungal cell membrane synthesizing enzyme), reported as an antifungal fluconazole binding enzyme. Based on our isolation-linked preliminary structure-activity relationship (SAR) data, we conclude that can be a good source of natural compounds for drug development against some potential enzyme targets.