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.

Planta Medica 84(11), 813-819 (2018). Fluorinated analogues of epigallocatechin-gallate were purified after synthesis by extraction with ethyl acetate from the synthesis mixtures, followed by column chromatography or (for two pairs of isomers) by preparative TLC. This isolation (as well as monitoring of column elution for the other compounds) was performed by TLC on silica gel with mixtures of n-hexane and (less) ethyl acetate in several concentrations, allowing the separation of diastereoisomers (RF values and yields are given). No derivatisation, visualisation because of fluorescing agent in the layers. Structures were identified by NMR and HR-MS, but apart from the TLC.

Planta Medica 84(9/10), 729-735 (2018). The chloroform fraction of a methanolic extract of Euphorbia taurinensis whole plant (Euphorbiaceae) was submitted to a multi-step fractionation through column chromatography. Monitoring by TLC on silica gel (mobile phases see below) followed by derivatization with concentrated sulfuric acid and heating at 105°C. The fractions obtained were purified by repeated cycles of preparative TLC alone or alternating with preparative HPLC, leading to the isolation of segetane, ingenane, and jatrophane diterpenes. Depending on the subfractions, preparative TLC silica gel and reverse-phase C18 layers were used, with cyclohexane – ethyl acetate – ethanol 25:15:1 for normal phase, and with mixtures of acetonitrile (or methanol) and water for RP.

Planta Medica 84(2), 129-134 (2018). TLC of subfractions obtained from normal-phase LC and size-exclusion chromatography of an ethanolic extract of Bougainvillea spectabilis (Nyctaginaceae) stem-bark on RP-18 with methanol – water 2:3 and 1:1 to isolate six flavones (bougainvinones J, K, L, M, and two dimethylflavone derivatives).

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.

Planta Medica 83(17), 1329-1334 (2017). Two acetone-soluble subfractions of an n-hexane maceration of Hypericum denudatum aerial parts (Hypericaceae) were submitted to repeated centrifugal planar chromatography (CPC) on silica gel using n-hexane – ethyl acetate (gradient from 100:0 to 90:10), obtaining four dimeric acylphloroglucinols (denudatin A, hyperbrasilol A, uliginosin B and isouliginosin B), which were purified by crystallisation with n-hexane – dichloromethane 9:1. From the most apolar CPC eluates, a monomer (selancin A) was isolated on preparative TLC silica gel layer by elution with n-hexane – ethyl acetate 97:3. Furthermore, all the purification steps were monitored through TLC on silica gel with n-hexane – ethyl acetate 19:1 or with n-hexane – dichloromethane 1:1. Detection under UV light after derivatization with anisaldehyde – sulfuric acid, monomeric acylphloroglucinols appeared purple, whereas dimers appeared yellow-orange.

Food Addit. Contam. Part A. 36, 1218-1227 (2019). Preparative TLC of florfenicol and florfenicol amine in porcine urine on silica gel with dichloromethane - acetone - ammonium hydroxide 20:20:1. Qualitative identification under UV light at 254 nm. Zones were scraped off and extracted for HPLC analysis.

J. of Chromatogr. A 1533, 180-192 (2018). HPTLC-UV/Vis/FLD-(bio)assay-HRMS of polar (phenolics) and nonpolar (tanshinones) extracts of Salvia miltiorrhiza Bunge root (Danshen), followed by streamlined scale-up to preparative layer chromatography with 1H-NMR. For phenolics, HPTLC on silica gel first with toluene - chloroform - ethyl acetate - methanol - formic acid 4:6:8:1:1 and second development with petroleum ether - cyclohexane - ethyl acetate 25:14:11. Confirmation of the acetylcholinesterase inhibitors salvianolic acid B (1), lithiospermic acid (2), rosmarinic acid (3), cryptotanshinone (4) and 15,16-dihydrotanshinone I (5). In the polar extracts, compounds (1), (2) and (3) exhibited free radical scavenging activity in the 2,2-diphenyl-1-picrylhydrazyl assay (DPPH* radical reagent), (4) and (5) were active against Bacillus subtilis and Aliivibrio fischeri (LOD of 12 ng/zone for (4), and 5 ng/zone for (5). For the first time, the unidentified, most active zone of the nonpolar Danshen extract was identified as a co-eluting zone of 1,2-dihydrotanshinone and methylenetanshinquinone 2:1.