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Betulinic acid (1), betulinic acid-3-acetate (2), 3-acetylbetulinaldehyde (3), oleanolic acid-3-acetate (4), 3-β-hydroxy-28,19-β-olenolide (5), and β-sitosterol (6) were isolated from Platanus orientalis and a high-performance thin-layer chromatography method was developed for their simultaneous quantification. The markers were first derivatized on the chromatogram with ceric ammonium sulfate and then high-performance thin-layer chromatography densitometry was carried out. Chromatographic separation of these markers was carried out on silica gel 60 plates using a ternary solvent system n-hexane/toluene/acetone (6:3.5:1 v/v/v) as a mobile phase. For marker 1, a deuterium (D2) lamp and wavelength of 420 nm was used. A tungsten (W) lamp was used for markers 2 and 3 at 550 nm and for 4-6 at 500 nm. The method was validated for accuracy, precision, LOD, and LOQ. All calibration curves showed a good linear relationship (r > 0.9919). The precision evaluated by an intra- and interday study showed RSDs < 2.51% and accuracy validation recovery between 95.54 and 99.33% with RSDs < 1.55%. The successful application of the validated method showed 1 as the most abundant component (4.63%) and 5 (0.017%) the least. The markers displayed a significant cytotoxic effect against human keratinocyte, mouse melanoma, and human skin epithelial carcinoma cancer cells by using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay.

A sensitive, selective and robust densitometric high-performance thin-layer chromatographic method was developed and validated for five marker compounds, namely betulin, lupeol, oleanolic acid, 3-acetyloleanolic acid and β-sitosterol, known for their various therapeutic activities. The marker compounds have been isolated from the stem bark of Betula utilis, well characterized by the spectral analysis, and their simultaneous quantitative determination carried out by high-performance thin-layer chromatography (HPTLC) method. The resolution of marker compounds was carried out on silica-gel 60 plates, using n-hexane:ethyl acetate (8:2 v/v) as the mobile phase. The HPTLC densitometry was performed at 500-nm wavelength after the post chromatographic derivatization with ceric ammonium sulfate reagent. The optimized method provided good linear relation (r>0.9960) for all the investigated analytes. The method is simple, and reproducible, which may be applied for quantitative analysis of the above-mentioned marker compounds.

A rapid and sensitive RP high-performance thin-layer chromatographic (RP-HPTLC) methodology was developed and validated for the quantitative estimation of gingerols in methanolic extract of fresh ginger rhizome. The samples were chromatographed on RP-TLC glass plates pre-coated with RP-18 60F(254) as the stationary phase. Linear ascending development was carried out in twin trough glass chamber saturated with ternary-solvent system consisting of acetonitrile-water-formic acid (7:2:1 v/v/v) at room temperature (25+/-2 degrees C) and plates were scanned at 500 nm. The system was found to give compact spots for gingerols (R(f) values of 6-gingerol 0.73+/-0.04, 8-gingerol 0.59+/-0.08 and 10-gingerol 0.36+/-0.05). Linearity was found to be in the range of 140-840 ng/spot for 6-gingerol, 168-1008 ng/spot for 8-gingerol and 136-816 ng/spot for 10-gingerol with significantly high value of correlation coefficient. The linear regression analysis data for the calibration plots showed linear relationship (r(2)) and ranged from 0.9992 to 0.9937 for 6-, 8- and 10-gingerol. The method was used for routine analyses and to obtain relative amounts of the gingerols in the fresh rhizomes of the ginger cultivated in different locations of Uttarakhand and Himachal Pradesh of North Western Himalayas (India).

High-performance thin layer chromatography (HPTLC) method for the separation and quantitative determination of ten markers (catechins, flavonoids, and phenolics) in different extracts of green tea and guava leaf has been developed and the antioxidant activity profiles of the two plant extracts have been determined. Ten marker compounds have been resolved using silica gel 60 F(254) plates, toluene/acetone/formic acid (5:4:1  v/v/v) for markers 1-6, and toluene/ethyl acetate/formic acid/methanol (3:3:0.8:0.2  v/v/v/v) for markers 7-10 as the mobile phases. The high-performance thin layer chromatography densitometry was performed at wavelengths of 282 and 285  nm for the markers 1-6 and 7-10, respectively. Potent antioxidant activity and the presence of phenolics and flavan-3-ols has been observed for the guava leaf extracts suggestive of its use as an alternate economical source of antioxidants over green tea--the well-established food additive/nutraceutical agent.