Anthocyanin-polyflavan-3 -ols

Krueger, C.G., Vestling, M.M., and Reed, J.D., Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry of anthocyanin-polyflavan-3-ol oligomers in cranberry fruit (Vacci-nium macrocarpon. Ait.) and spray-dried cranberry juice, ACS Symp. Ser., 886, 232, 2004. 

Recent advances in mass spectrometry allow for the characterization of complex mixtures of anthocyanin-polyflavan-3-ol pigments in wine... 

Anthocyanin-polyflavan-3-ols with B-Type and A-Type Interflavan Bonds... 

The Sephadex-medianol eluate (fraction 5) and Sephadex-80% aqueous acetone (v/v) eluate (fraction 6) contained a series of heteropolyflavan-3-ols which have been previously described (2) and indications of anthocyanin-polyflavan-3-ol oligomers of DP6 and greater. However, due to the large number of individual compounds within the heteropolyflavan-3-ol series and anthocyanin-polyfIavan-3-ol series it was difficult to obtain high mass spectral... 

Table I. Observed and Calculated Masses of Anthocyanin-polyflavan-3-ols in Spray Dried Cranberry Juice and Hyred Cranberry Fruit by MALDI-TOF MS...

Figure I. (A) Anthocyanins from Hyred cranberry fruit (Vaccinium macrocarpon, Ait.) and spray dried juice. (B) Tentative structure representing an anthocyanin linked through a CH3-CH bridge to a polyflavan-3-ol of 2 degrees of polymerization containing an A-type interfravan bond.

Anthocyanins in the presence of acidic matrixes such as MAA are predominately in the aromatic oxonium ion form 23) and are detected as [M] ions by MALDI-TOF mass spectral analysis 23,24). However, anthocyanins 23), in the same manner as polyflavan-3-ols 21,22,25), may also associate with naturally abundant sodium [M + Na] and potassium [M + K] forming alkali metal adducts. To suppress the formation of alkali metal adducts, we deionized the anthocyanin-polyfIavan-3-ol/matrix solution prior to deposition on the target. This approach resulted in the detection of andiocyanin-polyflavan-3 ols in die oxonium ion form [M]. ... 

A series of anthocyanins linked to polyflavan-3-ols of 2 degrees of polymerization (DP2) with either an A-type or B-type interflavan bonds (A 2 amu) were observed cyanidin-pentoside-DP2 (A-type = m/z 1021.2, B-type = m/z 1023.1), peonidin-pentoside-DP2 (A-type = m/z 1035.1, B-type = m/z... 

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