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  • Author or Editor: Ryszard Świeboda x
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Experimental results for the wicking process in a solid thin porous layer by liquids of different polarity with defined surface free energy components and viscosity has been considered theoretically. The method was used for determination of the solid surface free energy of the adsorbents used in thin layer chromatography. Experiments were performed on commercial glass plates precoated with silica, CN-silica, diol-silica, NH 2 -silica, and silanized silica with n -alkanes, diiodomethane, water, and formamide as mobile phases. Surface free energy components determined for investigated adsorbents were used for characterization and comparison of their surface properties.

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Seven different Scutellaria species were analyzed using the extraction procedure (Soxhlet apparatus, dichloromethane, and methanol as solvents) and thin-layer chromatography method. Selected standards of flavonoids and phenolic acids (caffeic acid, chlorogenic acid, ferulic acid, baicalein, wogonin, baicalin, chrysin, quercetin, scutellarin, hesperetin, hesperidin, apigenin, luteolin, rutin, and kaempferol) were separated using silica gel thin-layer chromatography (TLC) plates with the mobile phase consisting of ethyl acetate—toluene—formic acid (5:4.9:0.1, v/v) for dichloromethane and methanolic extracts. Dichloromethane extracts were also developed using cyanopropyl-bonded silica gel with the following mobile phases: propan-2-ol—n-heptane—formic acid (5:4.9:0.1, v/v) and methanol—water—formic acid (6:3.9:0.1, v/v), and after drying, they were sprayed using the anisaldehyde reagent. In the case of methanolic extracts, the same non-aqueous eluent was used and the aqueous eluent consisting of methanol—water—formic acid (4:5.9:0.1, v/v). The presence of selected standards in Scutellaria species was confirmed. The similarities between the obtained fingerprint chromatograms were performed using chemometric methods, the similarity coefficients (Pearson’s correlation coefficient, determination coefficient, and congruence coefficient), distance indices (Euclidean distance, Manhattan distance, and Chebyshev’s distance), and multi-scale structural similarity (MS-SSIM).

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Ten methanolic extracts of selected Cirsium species were analyzed using two-dimensional thin-layer chromatography (2D-TLC) system with octadecyl reversed-phase (RP-18) chromatographic plate as the stationary phase and two eluents: nonaqueous, consisting of 2-butanone‒toluene‒acetic acid (4.5:5:0.5, v/v) used in the first direction of developing, and aqueous, consisting of methanol—water—formic acid (4:5:1, v/v) used in the second direction. The Naturstoff reagent was used for the derivatization of some phenolic compounds. Five selected standards were analyzed under the same chromatographic conditions, and their retention factor values were used for the confirmation of their presence on selected Cirsium chromatograms. Photographs of ten chromatograms were treated using the ImageJ program. 2D-TLC analysis was also performed to obtain the fingerprint chromatographic profiles of the studied methanolic extracts. The experimental data were objected to principal component analysis (PCA), and the PC2 vs. PC3 graphs were created. Based on the PCA results, the similarity between the selected Cirsium species was confirmed.

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Fourteen different Achillea species were extracted using the Soxhlet apparatus with dichloromethane and then methanol as solvents. The obtained dichloromethane and methanolic extracts were analyzed using thin-layer chromatography (TLC) and high-performance thin-layer chromatography (HPTLC) to obtain fingerprint profiles. The first chromatographic system consisted of silica gel as adsorbent, a mixture of toluene—ethyl acetate—formic acid (5:4.9:0.1, v/v) as the mobile phase and anisaldehyde as the derivatization reagent. The second adsorbent was cyano (CN) silica gel with non-aqueous (2-propanol and n-heptane [5:5, v/v], both for dichloromethane and methanolic extracts) and aqueous (methanol and water [6:4, v/v] for dichloromethane extracts and methanol and water [4:6, v/v] for methanolic extracts) mobile phases. Anisaldehyde (for dichloromethane extracts) and Naturstoff (for methanolic extracts) derivatization reagents were used. The obtained chromatograms were processed to obtain selected images using the ImageJ program. The similarity between the studied Achillea species was confirmed using the chemometric methods (principal component analysis [PCA], similarity, and distance measures).

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Twenty land mosses were extracted by double maceration and ultrasonic extraction techniques using the mixture of 80% ethanol and water. The obtained extracts were analyzed using thin-layer chromatography (TLC) with silica gel (the mobile phase was consisted of ethyl acetate–formic acid–acetic acid–water, 14.0:1.5:1.5:2.0, v/v) and RP-18 (the composition of eluent methanol–water–formic acid, 7.0:2.5:0.5, v/v) chromatographic plates. After developing and drying, the plates were sprayed using the Naturstoff reagent, and after drying, the chromatograms were photographed and the obtained images were processed using the ImageJ program. Principal component analysis was performed to confirm the chemical similarity between the studied moss extracts. The cytotoxic activity of the ethanolic extracts of Bryophyta species was studied using the cell lines CCRF/CEM and CEM. For most of the moss samples, the cytotoxic activity was confirmed.

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