Berberine cation

R = Me) formation by the berberine cation (161) in methanol, while Skinner134 gives K = 3.8xl03M 1 for this same cation in ethanol. Kavalek et al.i2 found K(EtOH)/.K(MeOH) 300 for C-2 adduct (164)... 

Benztriazole, derivatives 281 ff 2-(2-Hydroxy-5-niethylphenyl)- 282 2-(2-Hydroxy-3-(l -methylpropyl)-5-tert-butylphenyl- 283 Berberine reagent 44,213 Beryllium cations 144,145,311,312 Besthorn s hydrazone reagent 347 Beta-blockers 74, 299, 301, 426—428 Beta-fronts 126 Beta-radiation 12 Betulae, Extr. 279 Betulic acid 59... 

Poly(dG-dC) poly(dG-dC) and its methylated analogue structures assume left-handed conformation (Z-DNA) in high molar sodium salt (Na", K" ), in low molar divalent cations (Ca", Mg", Ni ), micromolar concentrations of hexaamine cobalt chloride (Co(NH3)6)Cl3 and in millimolar concentrations of polyamines. In order to analyse the binding of berberine to Z-form DNA, Kumar et al. [186] reported that the Z-DNA structure of poly(dG-dC) poly(dG-dC) prepared in either a high salt concentration (4.0 M) or in 40 mM (Co(NH3)6)Cl3 remained invariant in the presence of berberine up to a nucleotide phosphate/alkaloid molar ratio of 0.8 and suggested that berberine neither bormd to Z-form DNA nor converted the Z-DNA to the... 

Wei et al. studied the separation of amines (aniline, ephedrine, codeine, cocaine, thebaine) and quaternary ammonium compounds (berberine, jatrorrhi-zine) on a bare silica stationary phase [44], A thorough study of the separation mechanism revealed a complex multifunctional mechanism. Contributions from differential electrophoretic migration were superimposed on hydrophobic, cation-exchange, and normal-phase interactions. Retention was highly dependent on the pH (optimal pH 8.3), ionic strength, and the amount of organic modifier. As the content of acetonitrile exceeded 80%, retention was consistent with a normal-phase mechanism. 

Recently, it has been demonstrated that medicinal plants contain MDR pump inhibitors that actually enhance the activity of their own natural antimicrobial compounds. Plant amphipathic cations, such as berberine, have been shown to be good MDR substrates. Recent research has shown that in addition to berberine, Berberis species produce 5 -methoxyhydnocarpin-D, Fig. 10, an MDR inhibitor that enhances the action of this compound. In addition, isoflavones isolated Ifom Lupinus argenteus were found to enhance the antibacterial activity of a-linolenic acid, also found in the same plant [99]. 

The analysis of berberine in crude drugs by means of pellicular cation-exchange columns have been reported by Akada et al.30 33. 

Nies et al. [182] have constructed OCT1 /M D R1 double transfectant and observed the transcellular transport of cationic plant alkaloid, berberine. To construct a set of double transfectants to mimic the transcellular transport in each organ is important for the understanding of the involvement of transporters in the pharmacokinetics of drugs. 

Salts are also observed. The presence of preformed ions in solution, i.e. cations and anions, perhaps generated in acidic HPLC effluent, will give rise to the cation or anion being directly observed without further manipulation. The analysis of an extract of Coptis japonica L. showed a protonated molecular ion due to canadine but the molecular cation is due to berberine, a naturally occurring quaternary ammonium salt (Fig. 5.11). 

Fig. 5.11 Analysis of an extract of Coptis japonica showing protonated molecule for canadine and the cation for berberine.

Figure 8. Mitochondrial delivery system based in lipophilic cations. (A) Triarylphosphonium salts (TPP) and (B) rhodamines are classic lipophilic cations used with chains of different lengths to bind a molecule of interest, targeting to mitochondria. (C) Berberine and palmatine, two cationic alkaloids that exhibit an accumulation in Av mi-dependent mitochondria, have been used to target antioxidant to mitochondria. (D) Two delivery systems based in TPP that allow to release an uncoupler (dinitrophenol, DNP) when mitochondrial ROS level is elevated (mitoDNP-SUM) or when a UV radiation favors the in situ cleavage of an rmcoupler (mitophotoDNP).

K. Lyamzaev, A. Pustovidko, R. Simonyan, T. Rokitskaya, L. Domnina, O. Ivanova, I. Severina, N. Sumbatyan, G. Korshimova, V. Tashlitsky, V. Roginsky, Y. Antonenko, M. Skulachev, B. Chernyak, and V. Skulachev, Novel mitochondria -targeted antioxidants plastoquinone conjugated with cationic plant alkaloids berberine and palmatine. Pharm. Res., 28 (2011) 2883-95. 

Berberine, jatrorrhizine, palmatine Coptidis chinensis CEC strong cation exchange on monolithic silica column. Mobile phase 12.5 mM phosphate (pH 7.4)-acetonitrile (40 60, v/v) UV at 263 nm [104]... 

Mikes V, Kovar J (1981) Interaction of liposomes with homologous series of fluorescent berberine derivatives. New cationic probes for measuring membrane potential. Biochim Biophys Acta 640 341-351... 

Otani M, Shitan N, Sakai K, et al. (2005) Characterization of vacnolar transport of the endogenous alkaloid berberine in Coptis japonica. Plant Physiol 138 1939-1946 Otsnka M, Matsumoto T, Morimoto R, et al. (2005) A human transporter protein that mediates the final excretion step for toxic organic cations. Proc Natl Acad Sci USA 102 17923-17928 Panicot M, Minguet EG, Ferrando A, et al. (2004) A polyamine metabolon involving aminopropyl transferase complexes in Arabidopsis. Plant Cell 14 2539-2551... 

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