Analysis of Catharanthus Alkaloids

I = 21 y = 0.394 r = 0.9476 F = 49.8 where log P is the hydrophobicity, bondrefr is the molecular refractivity, delta is the submolecular polarity parameter, ind indicator variable (0 for heterocyclics and 1 for benzene derivatives). Calculations indicated that PBD-coated alumina behaves as an RP stationary phase, the bulkiness and the polarity of the solute significantly influencing the retention. The separation efficiency of PBD-coated alumina was compared with those of other stationary phases for the analysis of Catharanthus alkaloids. It was established that the pH of the mobile phase, the concentration and type of the organic modifier, and the presence of salt simultaneously influence the retention. In this special case, the efficiency of PBD-coated alumina was inferior to that of ODS. The retention characteristics of polyethylene-coated alumina (PE-Alu) have been studied in detail using various nonionic surfactants as model compounds.It was found that PE-Alu behaves as an RP stationary phase and separates the surfactants according to the character of the hydrophobic moiety. The relationship between the physicochemical descriptors of 25 aromatic solutes and their retention on PE-coated silica (PE-Si) and PE-Alu was elucidated by stepwise regression analysis. 

This system is employed for the analysis of Catharanthus alkaloids including vinblastine C118). 

The following reversed-phase system has been used for the analysis of Catharanthus alkaloids including vinblastine by thermospray liquid chromatography-mass spectrometry (120). u Bondapak Ci8 (30cm x 3.9mm), reversed-phase column. 

Theodoridis, G. Papadoyannis, I.N. Hermans-Lokkerbol, A. Verpoorte, R. A study of the behaviour of some new column materials in the chromatographic analysis of Catharanthus alkaloids. Chromatographia 1997, 45, 52 57. 

The growing interest in secondary metabolites of plants leads to the requirement of the development on analytical method for the secondary product analysis. Chromatographic procedures for the determination of alkaloids have been well established. Based on the literatures published in past years, further improvement of the current methods for the analysis of Catharanthus alkaloids are needed [4]. Besides, the chemical complexity and unique bisindole alkaloid structure of the aforementioned molecules hindered their laboratorial synthesis. The isolation of VLB and VCR is laborious and costly, mainly due to their low contents in the plant and coexistence in a large number of other alkaloids [5]. Therefore, it is important for separation, identihcation, and quantiflcation of these Catharanthus alkaloids. The methods of extraction and purification were focused on liquid-liquid extraction, solid-phase extraction, supercritical fluid extraction (SFE), and molecularly imprinted polymers (MlPs)-based extraction. For separation, GC is not suitable for the bisindole alkaloids due to their high boiling point. The major methods for analysis of Catharanthus alkaloids are liquid chromatography (LC) and capillary electrophoresis (CE). 

Chromatographic method is commonly use and powerful technique for the analysis of Catharanthus alkaloids. Therefore, this chapter will focus on practical application of chromatographic and electrophoretical methods for analysis of Catharanthus alkaloids. 

Extraction and sample preparation are of importance in plant analysis. Clinic and forensic analyses usually rely on appropriate sample preparation to achieve a sufficiently low limit of detection. The pretreatment procedure before the chromatographic measurement must ensure exhaustive extraction of the analyte and removal of matrix that may interfere with analysis. Sample preparation methods for analysis of Catharanthus alkaloids include liquid-liquid extraction (LEE), supercritical fluid extraction (SEE), and molecularly imprinted polymers (MlPs)-based extraction. 

LC-MS for Catharanthus alkaloid analysis is a promising approach which will be increasingly used in the future, as interfaces are improved and highly selective solvent systems become available. The metabolites and catabolites of Catharanthus alkaloids can also be identified and determined by LC-MS conveniently. 

Uniyal GC, Bala S, Malhu A, Kulkami R (2001) Symmetry CIS column a better choice for the analysis of indole alkaloids of Catharanthus roseus. Phytochem Anal 12 206-210... 

GEERLINGS, A., MARTINEZ-LOZANO IBANEZ, M., MEMELINK, J., VAN DER HEIJDEN, R., VERPOORT, R., Molecular cloning and analysis of strictosidine P-D-glucosidase, an enzyme in terpenoid indole alkaloid biosynthesis in Catharanthus roseus. J. Biol. Chem., 2000,275,3051-3056. 

Trichophylline, a novel alkaloid isolated from the roots of Catharanthus trichophyllus, has the structure 131, according to X-ray crystal structure analysis (145). Reduction of trichophylline with sodium borohydride gives an unsaturated lactone, formulated as 132. Oxidative fission of the C/D ring system in vincadifformine derivatives has been observed previously hence, trichophylline may arise by oxidation at C-21 of an appropriate precursor, such as a 19-hydroxytabersonine (88) or 108, to the hydroperoxide 133, followed by fission of the 20,21-bond and simultaneous migration of C-18. 

Recently, we developed a LC-MS method for simultaneous determination of these five active alkaloids. Comparing with the two methods, MS can supply a high selectivity and sensitivity for determination of the analytes in positive mode and UV can obtain an excellent repeatability for analysis of them in Catharanthus roseus. In conclusion, the two methods have a good linear, reproducibility, precision, accuracy and recovery, and could be used for quantitative analysis of the five active compoimds in Catharanthus roseus. 

For analysis of alkaloids in Catharanthus roseus roots, Ferreres et al. describe a phytochemical study on this species roots. Alkaloids in aqueous extracts, the usual form of consumption of this matrix, were studied by HPLC-DAD-ESl-MS/MS, which allowed the identification of 19-S-vindolinine, vindolinine, ajmalicine and an ajmalicine isomer, tabersonine, catharanthine, serpentine, and a serpentine isomer. Quantification of the identified compoimds revealed that serpentine and its isomer were predominant (64.7 %) over the other alkaloids, namely, vindolinine and its isomer (23.9 %), catharanthine (7.7 %), and ajmalicine (3.8 %). The proposed procedures revealed to be simple, sensitive, and reproducible [13]. 

Ferreres F, Pereira DM, Valent P, Oliveira J, Faria J, Caspar L, Sottomayor M, Andrade PB (2010) Simple and reproducible HPLC-DAD-ESI-MS/MS analysis of alkaloids in Catharanthus roseus roots. J Pharm Biomed Anal 51 65-69... 

HPLC analysis for pharmaceutical preparations of alkaloids started about 30 years ago. Gas chromatography (GC) is suitable for volatile compoxmds and requires laborious derivatization. Thus, GC is unsuitable to analyze the bisindole alkaloids due to their high boiling point. HPLC can provide better analytical precision and higher sample loading capacity. HPLC methods coupled to UV and MS detection have been applied for the determination of the active compounds in Catharanthus roseus. 

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