Planta Med. 84(18), 1348-1354 (2018). A subfraction (obtained through liquid-liquid partition and column chromatography) of the ethanolic extract of whole Vernonia cinerea plants (Asteraceae, subf. Cichorioideae) was further fractioned by reverse-phase SPE (solid-phase extraction) followed by preparative TLC on silica gel layer (eluent not given). For verification, zones were detected by spraying with anisaldehyde solution with 10 % sulfuric acid, followed by heating at 100 °C. Further purification by reverse-phase HPLC allowed the isolation of 6 hirsutinolide-type sesquiterpenoids (all with a oxacyclonane forming an ether bridge), including vernolides A and B.

Planta Med. 84(18), 1340-1347 (2018). Preparative TLC on silica gel for the final purification of 15 phenylethyl-chromenone derivatives (including 3 with epoxide functions), 4 sesquiterpenoids (neopetasane, dehydrokaranone, dioxoselinene, ligudicin C) and a steroid (ergostatetraenone), all isolated through multi-step column chromatography from the ethyl-acetate fraction of a methanolic extract of Aquilaria sinensis resinous wood (Thymelaeaceae). For each compound, mobile phase, RF value and yield are given.

Phytochem. Anal. 31, 801-808 (2020). HPTLC of agarwood on silica gel with chloroform - methanol - distilled water 10:7:5. Detection by absorbance measurement at 254 nm. Agarotetrol was used as reference substance. Qualitative results were in agreement with the liquid extraction surface analysis mass spectrometry method.

J. Planar Chromatogr. 33, 457-462 (2020). HPTLC of scopoletin (1) and gallic acid (2) in the aerial parts of Jatropha glandulifera on silica gel with toluene - ethyl acetate - glacial acetic acid 75:25:1. Quantitative determination by absorbance measurement at 254 nm. The hRF values for (1) and (2) were 69 and 40, respectively. Linearity was between 100 and 600 ng for (1) and (2). Intermediate precision was below 2 % (n=3). The LOD and LOQ were 70 and 200 ng for (1) and 40 and 100 ng for (2), respectively. Recovery was between 98.8 and 98.9 % for (1) and 97.4 and 98.1 % for (2).

Planta Medica 84(6/7), 465-474 (2018). The new concept “Comprehensive HPTLC Fingerprinting” was applied to define specifications for the identification and purity assessment of Angelica gigas roots, and for the quantification of its markers: the coumarins decursin and decursinol angelate. Methanolic root extracts of A. gigas (10 reference materials, 24 commercial samples), of 26 other Apiaceae species (including 10 Angelica, 9 Ligusticum, 2 Notopterygium, 4 Peucedanum, and Levisticum officinale) and of mixtures, were developed with toluene - ethyl acetate - acetic acid 90:10:1 on HPTLC silica gel (at 33% relative humidity, chamber pre-saturated for 20 min with filter paper and developing solvent) and dried for 5 min. Detection under white and UV lights before and after derivatization by dipping into 10% sulfuric acid in methanol and then heating 3 min at 100°C. Quantitative evaluation by densitometry in fluorescence mode at UV 313 nm, and luminance was also calculated from the image pixels. The study showed the presence in A. gigas of nodakenin, decursinol, 7-demethylsuberosin, imperatorin, osthole, and isoimperatorin at hRF 0, 4, 15, 33, 38 and 44 respectively. Z-ligustilide (hRF 59) was absent from A. gigas, allowing 1) to distinguish it from several other Apiaceae species; 2) to identify in mixtures with A. gigas two common adulterants (A. acutiloba, A. sinensis) even at 1% in the root powder. Minimal content of A. gigas fingerprint markers (decursin + decursinol acetate, co-eluting at hRF 27) was assessed as 3% (w/w) based on the quantified peaks from A. gigas reference materials.

Planta Medica 84(1), 26-33 (2018). For the monitoring of the multi-step fractionation through VLC (vacuum liquid chromatography) of the chloroform-soluble parts of a methanol – water 7:3 percolate of Hippophae rhamnoides (Eleagnaceae) fruit peels, TLC on silica gel and RP-18, detection by spraying with sulfuric acid and heating. Preparative TLC on silica gel with cyclohexane – dichloromethane – methanol 5:15:1 to isolate, from VLC subfractions, three lignans (nectandrin B, fragransin A2, saucernetindiol) that are diastereoisomers of each other.

J. Planar Chromatogr. 32, 447-451 (2019). HPTLC of Fritillaria cirrhosa on silica gel with ethyl acetate - methanol - ammonia solution - water 180:20:10:1. Bioautography by dipping into a 0.15 mg/mL solution of substrate Gly-Pro-p-nitroanilide hydrochloride in 50 % of ethanol, followed by ethanol removal in the hood and dipping into a 10 U/L DPP IV enzyme solution in TrisHCl buffer (pH 8.2, 70 mM), followed by incubation at 37°C for 40 min. Detection by dipping into a solution of 0.5 % sodium nitrite in 1.2 M hydrochloric acid, followed by drying slightly for 5 min and dipping into 0.05 % N-(1-naphthyl)ethylenediamine dihydrochloride solution. Further analysis by mass spectrometry using a TLC interface. The hRF value for the dipeptidyl peptidase IV inhibitor was 58.

J. Ethnopharmacol. 235, 361-374 (2019). HPTLC of colchicine (1) and withaferin A (2) in the polyherbal ayurvedic formulation Peedantak Vati (PV) on silica gel with chloroform - 
methanol - water - formic acid 140:13:2:4. Quantitative determination by absorbance measurement at 218 nm. The hRF values for (1) and (2) were 22 and 28, respectively. LOD and LOQ were 40 and 120 ng/zone for (1) and 120 and 240 ng/zone for (2), respectively.