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SARS-CoV-2 (or COVID-19) has become a global risk and scientists are attempting to investigate antiviral vaccine. Berberis are important plants due to the presence of bioactive phytochemicals, especially berberine from the protoberberine group of benzylisoquinoline and recent studies have shown its potential in treating COVID-19. B. lycium Royle growing in subtropical regions of Asia had wide applications in Indian system of medicine. Rapid determination and novel optimisation method for berberine extraction has been developed by Soxhlet extraction utilising central composite design-response surface methodology (CCD-RSM). Berberine was detected by high-performance liquid chromatography (HPLC), and the highest yield (13.39%) was obtained by maintaining optimal extraction conditions i.e., extraction time (7.28 hrs), ethyl alcohol (52.21%) and solvent to sample ratio (21.78 v/w). Investigation of two geographic regions (Ramnagar and Srinagar) showed high berberine content in lower altitude. This novel optimisation technique has placed berberine as a potential candidate for developing pharmaceutical products for human health care. [ABSTRACT FROM AUTHOR]

Alantolactone and isoalantolactone are two isomeric sesquiterpene lactones that were isolated from Innula recemosa. Here, we are used for the semisynthesis of novel isoxazolidine hybrids of alantolactone and isoalantolactone through a two-step process: nitrone synthesis followed by nitrone 1,3-dipolar cycloaddition. The formation of the cycloadduct was well characterized via modern spectroscopic techniques such as HRMS, 1 H NMR, 13 C NMR, DEPT-90, DEPT-135, and 2D NMR. This study also includes the synthesis of dinitrone with glyoxal and terephthalaldehyde, which is used for the dinitrone cycloadduct of alantolactone and isoalantolactone. Both nitrone cycloaddition and dinitrone cycloaddition proceed with high regio- and diastereoselectivity, resulting in the formation of only one isomer. The formation of the α-cycloadducts and the absolute configuration were established through 2D NMR and single-crystal X-ray diffraction analysis. The antimicrobial activity of all synthesized compounds was evaluated against a panel of Gram-positive and Gram-negative pathogens. Compounds 3f and 4f exhibited potential antimicrobial activity against drug-sensitive and -resistant Staphylococcus aureus strains, with minimum inhibitory concentrations ranging from 6 to 10 µM. A time-kill kinetics assay suggested that compounds 3f and 4f are bacteriostatic. Furthermore, scanning electron microscopy analysis confirmed that compounds 3f and 4f cause significant morphological alternations and exert potent antibacterial effects by causing substantial cellular damage., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Toona ciliata , a member of the Meliaceae family, is valued for its high-quality timber and medicinal potential in treating various ailments. In this study, two triterpene isomers were isolated and characterised as an inseparable mixture from its chloroform extract using chromatography and spectroscopic techniques. Despite rigorous/extensive attempts to separate these isomers, they co-crystallised in a consistent 67:33 ratio, as verified by X-ray crystallography. The structure was further confirmed by ESI-MS, HRMS, 1 H NMR, 13 C NMR, DEPT 90, DEPT 135, COSY, NOESY, HSQC, and HMBC. Additionally, four more compounds were isolated successfully, out of that lutein and dyscusin C found for the first time from this plant.