{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,18]],"date-time":"2026-05-18T16:53:11Z","timestamp":1779123191918,"version":"3.51.4"},"reference-count":44,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,4,2]],"date-time":"2021-04-02T00:00:00Z","timestamp":1617321600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Admittedly, the disastrous emergence of drug resistance in prokaryotic and eukaryotic human pathogens has created an urgent need to develop novel chemotherapeutic agents. Onosma chitralicum 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 Onosma chitralicum, 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 n-C6H14 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 1 to 7 were isolated. Different techniques, such as UV, IR, and NMR, were used to characterize the structures of the isolated compounds 1\u20137. All the isolated pure compounds (1\u20137) were tested for their antimicrobial potential. Compounds 1 (4\u2032,8-dimethoxy-7-hydroxyisoflavone), 6 (5,3\u2032,3-trihydroxy-7,4\u2032-dimethoxyflavanone), and 7 (5\u2032,7,8-trihydroxy-6,3\u2032,4\u2032-trimethoxyflavanone) were found to be more active against Staphylococcus aureus and Salmonella Typhi. Compound 1 inhibited S. typhi and S. aureus to 10 \u00b1 0.21 mm and 10 \u00b1 0.45 mm, whereas compound 6 showed inhibition to 10 \u00b1 0.77 mm and 9 \u00b1 0.20 mm, respectively. Compound 7 inhibited S. aureus to 6 \u00b1 0.36 mm. Compounds 6 and 7 showed significant antibacterial potential, and the structure\u2013activity 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 7, the best binder to the lanosterol 14\u03b1-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 O. chitralicum can be a good source of natural compounds for drug development against some potential enzyme targets.<\/jats:p>","DOI":"10.3390\/molecules26072048","type":"journal-article","created":{"date-parts":[[2021,4,3]],"date-time":"2021-04-03T22:03:36Z","timestamp":1617487416000},"page":"2048","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["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"],"prefix":"10.3390","volume":"26","author":[{"given":"Shakeel Ahmad","family":"Khan","sequence":"first","affiliation":[{"name":"Department of Chemistry, Kohat University of Science &amp; Technology, Kohat 26000, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9231-1831","authenticated-orcid":false,"given":"Shafi Ullah","family":"Khan","sequence":"additional","affiliation":[{"name":"School of Pharmacy, Monash University, Bandar Sunway, Subang Jaya 47500, Malaysia"},{"name":"Department of Pharmacy, Abasyn University, Ring Road, Peshawar 25120, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"family":"Fozia","sequence":"additional","affiliation":[{"name":"Biochemistry Department, KMU Institute of Medical Sciences, Kohat 26000, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0900-5927","authenticated-orcid":false,"given":"Najeeb","family":"Ullah","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Bahauddin Zakariya University, Multan 60800, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6126-7102","authenticated-orcid":false,"given":"Mohibullah","family":"Shah","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Bahauddin Zakariya University, Multan 60800, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2860-467X","authenticated-orcid":false,"given":"Riaz","family":"Ullah","sequence":"additional","affiliation":[{"name":"Department of Pharmacognosy, College of Pharmacy, King Saud University Riyadh Saudi Arabia, Riyadh 11495, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ijaz","family":"Ahmad","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Kohat University of Science &amp; Technology, Kohat 26000, Pakistan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9819-447X","authenticated-orcid":false,"given":"Amal","family":"Alotaibi","sequence":"additional","affiliation":[{"name":"Basic Science Department, College of Medicine, Princess Nourah bint Abdulrahman University, Riyadh 11671, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,2]]},"reference":[{"key":"ref_1","first-page":"79","article-title":"Antibacterial activity of aqueous and ethanol extracts of mangrove species collected from Southern Sri Lanka","volume":"2","author":"Abeysinghe","year":"2012","journal-title":"Asian J. 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