Authors:X. Liu, H. Zhang, Z. Tan, K. Han, and L. Sun
The isoquinoline alkaloids were isolated from traditional Chinese drugs of Phellodendri Cortex, Radix Stephaniae Tetrandrae,
Corydalis Yanhusuo and Corydalis Bungeana. The power-time curves of growth of E. coli at different concentrations of isoquinoline alkaloid at 37�C were determined by a 2277 Thermal Activity Monitor. The rate
constant of bacteriostastic activity was calculated. The relationship between growth rate constant and concentration was established.
The optimum bacteriostastic concentration was determined. Experimental results have indicated that all the isoquinoline alkaloids
isolated from the four kinds of traditional Chinese drugs have bacteriostastic activity and the order is Phellodendri Cortex>Radix
Stephaniae Tetrandrae>Corydalis Yanhusuo>Corydalis Bungeana.
A simple and inexpensive two-dimensional thin-layer chromatography (2D-TLC) method was applied with mobile phase containing ionic liquid (IL) for the separation of ten components of a mixture of isoquinoline alkaloids such as allocryptopine (A), berberine (Be), boldine (Bo), chelidonine (Ch), papaverine (Pa), emetine (E), columbamine (Col), magnoflorine (M), palmatine (Pal), and coptisine (Cop). Separation of the alkaloid mixture was achieved by 2D-TLC using an aqueous mobile phase (RP) in the first dimension (80% methanol—water–0.05 M L−1 diethylamine) and a normal phase (NP) in the second dimension (75% methanol [MeOH], 24.75% ethyl methyl ketone–0.25% IL (1-butyl-3-methylimidazolium tetrafluoroborate) (v/v) on bilayer Multi-K CS5 plates. The procedure was evaluated in terms of natural samples analysis. Coptisine, palmatine, and berberine were identified in Rhizoma Coptidis (Huang Lian) extract. Additionally, the alkaloids in the extract sample were confirmed by high-performance liquid chromatography–diode-array detection (HPLC—DAD) method with application of a Synergi Polar RP column and a mobile phase consisting of a mixture of 25% acetonitrile (MeCN), 0.25% IL (1-butyl-3-methylimidazolium tetrafluoroborate), and 74.75% water (v/v). The composition of the mobile phases was optimized in terms of retention, separation selectivity, spots symmetry, and system efficiency. Limits of detection (LODs) were from 0.10 and 0.13 μg mL−1 and limits of quantification (LOQs) between 0.31 and 0.41 μg mL−1.
Authors:M. Waksmundzka-Hajnos, D. Matosiuk, A. Petruczynik, and U. Kijkowska-Murak
Nine alkaloids were chromatographed by reversed phase (RP) TLC on RP-18 with aqueous acetone or aqueous dioxane mobile phases. A variety of mobile phase additives (ammonia, diethylamine (DEA), tetrabutylammonium chloride (TBA-Cl)) were used to suppress ionization of the alkaloids and/or reduce ionic interactions with surface silanol groups. Ion-pair (IP) RP-TLC was also performed with aqueous acetone mobile phases and reagents such as pentane sulphonic acid (PSA), octane sulphonic acid (OSA), or di-(2-ethylhexyl)orthophosphoric acid (HDEHP) as mobile phase additives. In these systems retention of the alkaloids was determined using mobile phases with different modifier concentrations. Relationships between RM and modifier concentration were sought. A linear semilogarithmic equation was fitted to experimental data and used to obtain lipophilicity values RMW (RM for pure water), the slope (S), and ϕ0, the intercept with the x-axis. The retention of standards with known lipophilicity log P was then determined using the chromatographic systems described above and RMW values were calculated. From these experimental data equations relating log P and RMW were created for each system separately and these equations were used to estimate log Pexp values for the alkaloids. log Pexp, slope (S), and ϕ0 values obtained by use of different TLC systems were also correlated.
Authors:A. Petruczynik, K. Śliwka, and M. Waksmundzka-Hajnos
The effect of conditioning of the silica layer by mobile phase vapour, diethylamine vapour and its aqueous and methanolic solutions, and ammonia vapour on the retention of alkaloids eluted with multicomponent non-aqueous mobile phases was examined. Effect of conditioning time and vapour phase composition on system efficiency and peak symmetry was investigated, as also was the effect of vapour phase composition on separation selectivity. The most effective and selective systems were used for separation of the alkaloid fraction from Fumaria officinalis.
Authors:Ágnes Sárközi, Ágnes Móricz, Péter. Ott, Ernő Tyihák, and Ágnes Kéry
The greater celandine (
L.), a well-known source of isoquinoline alkaloids, has a long history of use as a medicinal plant. Although the antimicrobial activity of
alkaloids against pathogenic bacteria has been reported, the mechanism of this action is almost unknown. The BioArena system, which integrates the modern method and biological results of bioautography with TLC and/or OPLC, is especially suitable for investigating biochemical interactions in the adsorbent layer after chromatographic separation. The antimicrobial effect of alkaloids obtained from
root has been demonstrated by use of this system. It was assumed that the antibiotic activity of
alkaloids was a result of formation of formaldehyde. It was also assumed that addition of endogenous HCHO-capture molecules, for example l
-arginine and glutathione, to the culture medium reduces the antibacterial activity of
alkaloids whereas Cu(II) ions enhance the effect. The results obtained support these assumptions and our earlier observations that HCHO and its reaction products are very important in the antibiotic action of these compounds. These small molecules (l
-arginine and glutathione) can capture HCHO molecules mobilized by alkaloids and possibly by pathogen cells, and may be responsible for reduced antibacterial effect. The HCHO-mobilizing power of Cu(II) ions dramatically enhanced the antibiotic effect. The BioArena system is highly suitable for studying special interactions in the adsorbent layer.
Authors:Tomasz Tuzimski, Anna Petruczynik, and Justyna Misiurek
In this study, authors propose a simple and cost-effective two-dimensional thin-layer chromatography (2D-TLC) method for the simultaneous determination of eleven standards alkaloids: allocryptopine (A), berberine (Be), boldine (Bo), chelidonine (Ch), glaucine (G), papaverine (Pa), emetine (E), columbamine (Col), magnoflorine (M), palmatine (Pal), and coptisine (Cop). Separation of the alkaloid mixture was achieved by 2D-TLC using an aqueous mobile phase (RP) in the first dimension (80% methanol + water + 0.05 mL−1 diethylamine) and a normal phase (NP) in the second dimension (18% methanol, 18% acetone in 63% diisopropyl ether containing 1% ammonia, v/v) on bilayer Multi-K CS5 plates. The composition of the mobile phases was optimized in terms of retention, separation selectivity, spots symmetry, and system efficiency. The procedure was evaluated in terms of natural samples analysis. Magnoflorine and berberine were identified in Thalictrum foetidum root extract. Additionally, the alkaloids in the extract sample were confirmed by high-performance liquid chromatography—diode-array detection method.
Authors:Gergely Sámuel Bartha, Gergő Tóth, Péter Horváth, Eszter Kiss, Nóra Papp, and Monika Kerényi
acid ester (6-methyl-5-hepten-2-yl acetate), terpenes (limonene, linalool, and p-cymene), sesquiterpene (bicyclogermacrene), and sesquiterpenoid (spathulenol; Santos et al., 2014 ). Isoquinolinealkaloids (constrictosoines) were isolated from the