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An important bioactive molecule, ursolic acid was isolated from the leaves of Diospyros melanoxylon and characterized with help of physical and spectroscopic data viz. m. p, IR, 1H, and 13C NMR. A high-performance thin-layer chromatography method has also been developed and validated for its quantification in D. melanoxylon leaves. The high-performance thin-layer chromatography analysis was performed on high performance thin-layer chromatography plates using chloroform-methanol (9.5:0.5, v/v) as mobile phase. The compound was quantified at 540 nm after derivatzation with sulphuric acid reagent. The sensitivity of the method with respect to limit of detection and limit of quantification were found to be 20 and 40 ng per spot. The response was obtained as a linear function of peak area and concentration in the range of 50 to 450 ng per spot with correlation coefficient of r 2 = 0.9998. The method showed excellent accuracy greater than 97.54% with acceptable precession and was successfully validated according to International Conference of Harmonization protocols. Antimicrobial screenings of ursolic acid revealed potent activity against two Gram-positive bacteria viz. Staphylococcus aureus and Enterococcus faecalis and three fungal starins viz. Aspergillus niger, Candida tropicalis, and Candida albicans.

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Lupenone was isolated for the first time from the stem bark of Diospyros melanoxylon and characterized with the help of physical and spectroscopic data. A high-performance thin-layer chromatography (HPTLC) method has been developed and validated for the quantification of lupenone in D. melanoxylon stem bark. HPTLC analysis was performed on HPTLC plates by using a binary mobile phase of n-hexane–ethyl acetate (8.2:1.8, v/v). It was quantified at 395 nm after derivatization with methanol—sulfuric acid reagent. The limits of detection and quantification were found to be 40 ng and 100 ng per spot, respectively. The linear regression analysis data for the calibration plot in the range of 100–500 ng spot−1 showed a good linear relationship between peak area and concentration (r 2 = 0.9997). The instrumental precision was 1.01% (coefficient of variation [CV]) and the repeatability of the method was 2.17% (CV). The method was validated for precision, recovery, and repeatability as per the International Conference on Harmonization guidelines. The developed HPTLC method is very accurate and precise and has been successfully used for the estimation of lupenone in D. melanoxylon stem bark.

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A high-performance thin-layer chromatography (HPTLC) method has been developed and validated for the quantification of two bioactive lupane triterpenoids, namely, lupeol and betulin from Diospyros melanoxyon stem bark. Chromatographic separation was achieved on aluminium foil-backed HPTLC plates using ethyl acetate-hexane (1.8:8.2, v/v) as mobile phase. The compounds were quantified at their wave length of maximum absorbance in the range of 100–500 ng per spot. The instrumental precision was 0.82% and 1.07% (CV) and the repeatability of the method was 1.33% and 1.17% (CV), respectively, for lupeol and betulin. The minimum detectable amount was found to be 40 and 50 ng per spot for lupeol and betulin, respectively. The linear regression analysis data for the calibration plots showed a good linear relationship with r 2 = 0.9996 for lupeol and 0.9997 for betulin. The method was validated for precision, recovery, and repeatability as per the International Conference on Harmonization guidelines. The developed HPTLC method is very accurate and precise, and has been successfully applied for the assay of these bioactive molecules in D. melanoxylon stem bark.

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