Iridoids chromatography

A General Description of Apocynaceae Iridoids Chromatography 151 http //dx.doi.org/10.5772/55784... 

Suomi, J., Wiedmer, S. K., Jussila, M., and Riekkola, M. L. (2002). Analysis of eleven iridoid glycosides by micellar electrokinetic capillary chromatography (MECC) and screening of plant samples by partial filling (MECC)-electrospray ionization mass spectrometry.. Chromatogr. A 970, 287-296. 

The methanol extract of the leaves of Cerhera manghas and its fruit contain the iridoids theve-side and theviridoside, as described in [124]. The methanol extract of the leaves, after the addition of water, was sequentially partitioned with chloroform, acetic acid and butanol. This extract and the aqueous phase were submitted to column chromatography with charcoal and water/ methanol as eluent. Theveside was isolated from the aqueous phase. Fractions of the butanol extract, which turn blue after heating with mineral acid, were chromatographed over a silica gel column with a gradient of increasing polarity of chloroform/methanol to afford theviridoside. 

Isoplumericin and plumericin are present in the bark of Himatanthus sucuuba [88]. For the isolahon of these iridoids, 95% ethanol extract (2 g), obtained from 50 g of plant material was submitted to column chromatography using silica gel and gradients of increasing polarihes with hexane, ethyl acetate and methanol. After recrystallizahon, isoplumericin (18 mg) was obtained from ethyl acetate and plumericin (70 mg) from methanol. 

Studies on HPLC with iridoids of Apoc)maceae focus mainly on the separation of components from extracts or fraction. The chromatography profile, the identification and quantification of these terpenes in the extracts are described. Table 4 shows the principal references on iridoids isolated from Apoc)maceae by HPLC, MPLC and LPLC. 

The literature describes chromatographic techniques related to the characterization, isolation and purification of iridoids. Most reports show the open column technique as the principal technique used to isolate this class. Also, there have been few studies on counterflow and capillary electrophoresis chromatographies. In general, there has been little scientific investment in the area of obtaining iridoids of the Apoc3maceae family, despite the great pharmacological importance of this class of constituents. 

Wu H-K, Chuang W-C, Sheu S-J. Separation of nine iridoids by capillary electrophoresis and high-performance liquid chromatography. Journal of Chromatography A 1998 803(1-2) 179-187. 

Thirty-three known iridoid and secoiridoid glucosides have been analysed by gas chromatography of their trimethylsilyl derivatives. G.c.-m.s. analysis of several representative compounds e.g. 4-CO2H, 4-C02Me, 4-unsubstituted) demonstrated the feasibility of iridoid-containing plant extract analysis and resulted in the identification of secologanoside 11-methyl ester (99 R = H, X = CH2) from Lonicera morrowii the sixth paper in a series of chemotaxonomic studies on iridoids illustrates the need for accurate analysis of minor components. ... 

The CNS depressant component of valerian is still unknown. Thus far, three major constituents of valerian have been identified the volatile or essential oil, containing sesquiterpenes and monoterpenes, nonglycosidic iridoid esters (valepotriates), and a small number of alkaloids (Anonymous, 1991). Valepotriates are unstable compounds and are easily hydrolyzed by heat and moisture (Wagner et al., 1998). In addition, valepotriates are not water soluble, and aqueous extracts contain small amounts (Wagner et al., 1998). For example, the aqueous extract used in the study by Balderer and Borbely, described previously, was analyzed using thin-layer chromatography (TLC), and no valepotriates were detectable. Furthermore, valepotriates are not well absorbed orally (Tyler, 1993). Therefore, the likelihood that valepotriates are a major contributor to valerian s effects is questionable. Because of the low amount of alkaloid present in preparations, their contribution is also questionable (Houghton,... 

Fractionation of the water-soluble part of an ethanol extract of N. florihunda by reverse phase chromatography gave, together with verbascoside, the iridoid glucoside unedoside (1), as well as two unknown iridoid diglycosides 2 and 3. 

Suomi, J. et al., Determination of iridoid glycosides by micellar electrokinetic capillary chromatography-mass spectrometry with use of the partial filling technique, Electrophoresis, 22, 2580, 2001. 

Demirezer LO, Gurbuz F, Guvenalp Z, Stroch K, Zeeck A (2(X)6) Iridoids, flavonoids and monoterpene glycosides from Galium verum subsp. verum. Turk J Chem 30(4) 525-534 Derksen GC, Niederlander HA, van Beek TA (2(X)2) Analysis of anthraquinones in Rubia tinctorum L. by liquid chromatography coupled with diode-array UV and mass spectrometric detection. J Chromatogr A 978(1-2) 119-127... 

Isolation of individual iridoids by traditional silica gel/alumina/charcoal/ dianion/Sephadex column chromatography is tedious because of their close Rf values and polar nature. Application of HPLC techniques using octadecyl-silanized (0DS)Si02/CigSi gel colunm or HPLC coupled with a diode-array detector and a mass spectrometer (HPLC-DAD-MS) has achieved efficient separation... 

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