Planta Med. 57, 176-180 (1991). TLC of caffeic acid derivatives, of lipophilic flavones and of flavonol glycosides on silica with ethyl acetate - formic acid - acetic acid - water 100:5:5:13 or with dichloromethane - methanol 95:5, and on microcrystalline cellulose with 15% acetic acid. Purification of flavones by preparative TLC on polyamide with toluene - petrol ether - MEK - methanol 30:60:5:5.

J. Liquid Chromatogr. 15, 1719-1727 (1992). TLC of hydroxy and carboxy benzene derivatives on 1% Fe(NO3)3-impregnated silica with water. Detection by spraying with bromocresol green indicator solution. Investigation of the influence of progressive drying of Fe(III)-hydroxide support on the behavior of the substances.

Biochemical Systematics and Ecology 22, 341-351 (1994). TLC of salicortin and tremulacin on silica with dichloromethane - methanol - tetrahydrofuran 6:1:1. Densitometry by absorbance at 274 nm.

J. Agric. Food Chem. 45, 873-876 (1997). TLC of phenolic extracts on silica with propanol - 8 N NH3 (3:1), benzene - acetic acid 45:4, and benzene - dioxane - acetic acid 95:25:4. In addition analytical and semipreparative two-dimensional TLC of 2,3-dihydroxy-1-guaiacylpropan-1-one on cellulose with 2% formic acid and isopropanol - NH3 - water 8:1:1. Detection under UV 254 and 366 nm, before and after saturation with NH3, and by spraying with several reagents (e.g. diazotised 4-nitroaniline - 15% sodium carbonate; 2.5% phloroglucinol in 12 N hydrochloric acid - ethanol 1:3; 0.4% catechin in acetone - water - sulfuric acid 4:3:1).

J. Planar Chromatogr. 11, 283-294 (1998). Examination of the retention of different groups of model substances - 16 phenols, 12 amines, 6 quinoline bases - on polar adsorbents - silica gel, alumina, and Florisil - developed with isoeluotropic eluents. The DRM (Dlogk, selectivity) parameters for different substituents of the compounds were compared as parameters of the energies of adsorption of the various chromatographic systems. The DRM values for substituents were correlated with their reactivity constants.

Cordata. Planta med. 66, 257-261 (2000). Preparative TLC of 12b-orcinolcarboxylate on silica gel with dichloromethane - methanol 24:1 and 99:1. Detection under UV 254 nm.

J. Planar Chromatogr. 17, 84-88 (2004). OPLC of trans-resveratrol on silica gel with chloroform - methanol 10:1 after preconditioning of the plates for 3 h at 120 °C. Detection by immersion of the dried plates in a bacterial suspension (Pseudomonas savastanoi pv. phaseolicola race 6) for 20 s and MTT staining (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide; 80 mg MTT and 100 mg Triton X-100 in 100 mL water) either after a short draining period or after overnight incubation; after staining the time for evaluation varied (e. g. from 1 h to 6 - 9 days or more). First results of the investigation of a complex bioautographic system with special emphasis on the direct effect of the antibiotic trans-resveratrol (fitoalexin) and the function of formaldehyde in relation to antibiotics.

J. Chromatogr. A 1216(20), 4485-4491 (2009). TLC of (+)-catechin and (-)-epicatechin on cellulose with water. Detection with 4-dimethylaminocinnamaldehyde in HCl produced blue bands. Detection with vanillin reagent produced quickly fading red spots. Quantitative determination by absorbance measurement at 655 nm. Linearity was between 2 to 12 ng/zone and a polynomial regression fit from 2 to 30 ng/zone. The repeatability of the separation of 20 ng/zone was 3.5 % (%RSD, n = 6). The visible limit of detection of both standards was 1 ng/zone, the densitometric limit of detection was 0.2 ng/zone. The optimized 4-dimethylaminocinnamaldehyde reagent is superior to the more frequently used vanillin reagent and is applicable also for determination of mixtures containing other catechins, such as (-)-catechin, (-)-epicatechin gallate, (-)-epigallocatechin gallate, procyanidin A2, procyanidin B1 and procyanidin B2.