The chromatographic behavior of petanin, petunidin-3-O-[6-O-(4-O-(E)-para-coumaroyl-O-α-rhamnopyranosyl)-β-glucopyranoside]-5-O-β-glucopyranoside, is studied for the first time under conditions of reversed-phase high performance liquid chromatography in mobile phases with different pH values. The relationship between chromatographic behavior (retention time and peak efficiency) and transitions between different forms of anthocyanins is discussed. Analysis of the data obtained in the 2 to 6.5 range of mobile pH phases, the absorption spectra of petanin, and the results from studying the effect of adding tetrabutylammonium bromide to the mobile phase shows that increasing the pH results in the formation of uncharged and anionic forms, in addition to the pseudobase form.
LINK
The selectivity of the separation of some anthocyanins on Diasphere-11-C10CN stationary phase (phase I) is compared with the traditional reversed Symmetry C18 phase (phase II). It is found that, in contrast to phase II, phase I is effective in the separation of isomeric pairs of anthocyanins of 6-hydroxycyanidin-3-rutinoside and delphinidin-3-rutinoside, 6-hydroxypelargonidin-3-rutinoside and cyanidin-3-rutinoside, which ensures the determination of anthocyanins of Alstroemeria flowers. A comparison of separation maps shows that, on phase I, as compared with phase II, retention does not decrease so much, when OH groups are added to the anthocyanidin structure; trend lines for 3-mono-, di-, and triglucosides have a higher slope, and the addition of a glucosidic substituent at position 5 results in a more significant decrease in the retentionof anthocyanins. Different selectivity of the separation of anthocyanins on phase I makes this separation version a good alternative to traditional reversed phase chromatography.
DOCUMENT
The anthocyanin composition of five purple leaves cultivars of Ocimum basilicum L. was investigated by reversed-phase HPLC with mass-spectrometric detection by ESI mode with ion partial fragmentation as well as preparation of dried differently colored forms of anthocyanins encapsulated into maltodextrinmatrix. Analysis of the mass spectra revealed that according to the chromatographic profile the set of basil cultivar anthocyanins under investigation may be divided into two groups with the common feature being ahigh level of acylation with (mainly) p-coumaric, ferulic and malonic acids of the same base: cyanidin-3-dihexoside-5-hexoside. The presence of acylation with substituted cinnamic acids permits us to obtain solutions not only with a red color (the property of the flavylium form) but also with blue shades of coloration due to quinonoid and negatively charged quinonoid forms. All forms except that of flavylium are not stable in solution but stable enough to prepare dried encapsulated forms by lyophilization. Although the loss of anthocyaninswith drying is not negligible, the final product is characterized with high stability for storage in a refrigerator.
DOCUMENT
