Survey of Polyphenol Constituents in Grapes and Grape-Derived Products

Abstract

A rapid and comprehensive qualitative method has been developed to characterize the different classes of polyphenols, such as anthocyanins, flavonols, phenolic acids, and flavanols/proanthocyanidins, in grape products. The detection was achieved by two runs with the same LC gradient in different MS ionization modes and mobile phase modifiers (positive ionization mode and 0.4% trifluoroacetic acid for anthocyanins and flavonols; negative ionization mode and 0.1% formic acid for phenolic acids and flavanols). From an analysis of the MS and UV data and in comparison with the authenticated standards, a total of 53 compounds were identified, including 33 anthocyanins, 12 flavonols, 4 phenolic acids, and 4 flavanols/proanthocyanidins. With the method developed, a survey was then conducted to qualitatively assess the composition of polyphenols among 29 different grape products including original grape, grape juice, grape wine, and grape-derived dietary supplements, and their chemical profiles were systematically compared. This method provided a comprehensive qualitative insight into the composition of polyphenols in grape-derived products.

Quantification of anthocyanidins in the grapes and grape juice products with acid assisted hydrolysis using LC/MS

“…To facilitate the quantification and accurately evaluate the total anthocyanidins in the grape juice products and grape berries and grape skins, we developed an acid-assisted hydrolysis method. In our previous study we only detected trace amount of pelargonidin derivatives that could not be detected in all grape juice samples (Xu et al, 2011), therefore, pelargonidin was not included in this quantification study. Under optimized LC-MS condition, five anthocyanidins, delphinidin, cyanidin, petunidin, peonidin and malvidin were successfully separated within 25 min and quantified in the hydrolyzed samples by UV detection at 520 nm.…”

“…A previous qualitative study enabled us to identify numerous anthocyanins in the grape juice products, grape berries and grape skins (Xu et al, 2011). Due to the high number of different anthocyanins and limited availability of commercial standards, it was difficult to develop an analytical method to accurately quantify all the anthocyanins in the original grape samples.…”

“…A wide variety of anthocyanins in grapes and grape-derived products, coupled with their chemical similarity results in a large number of peaks and difficulty to separate and quantify individual anthocyanins in grape matrices. In a previous qualitative study, we identified a total of 33 anthocyanins, in which 27 anthocyanins were once detected in a single grape juice sample (Xu et al, 2011). Given the enormous variety of anthocyanins, and lack of authentic reference standards for the great majority of these derivatives, it remains challenging to accurately quantify the anthocyanin composition and concentration in the grape and grape derived products.…”

Characterization of Polyphenolics in Grape Pomace Extracts Using ESI Q-TOF MS/MS

“…The [M+H] + ion at m/z 479*(* stands precursor ions generated from ESI+ mode) was detected in both RGPE and WGPE (Figure 1 C,D), which was assigned to petunidin-3-glucoside confirmed by its fragments at m/z 303 and 317 (Table 2) [26]. The [M+H] + ions at m/z 463*, 493*, 505*, 535*, 625*, 639*, and 655* could be assigned to peonidin 3-glucoside, malvidin 3-glucoside, peonidin 3-acetylglucoside, malvidin 3-acetylglucoside, petunidin 3-p-coumaroylglucoside, malvidin 3-p-coumaroylglucoside, and malvidin 3-(6-O-caffeoyl) monoglucoside (Figure 1 C,D (Table 2), respectively [26][27][28]. Of which, peonidin 3-glucoside and peonidin 3-acetylglucoside were detected in both RGPE and WGPE, while malvidin derivatives and petunidin 3-p-coumaroylgluside only found in RGPE ( Table 2).…”

Plant polyphenol content, soil fertilization and agricultural management: a review

“…Taking into account the reviews published since 2008, a general overlook on the research topics can emphasize the main current fields in which the research is presently developed. The different subjects which may be inferred are: problems in the analytical assays of polyphenols [1][2][3][4][5], polyphenols composition of fruits and vegetables [6][7][8][9][10], the fate of polyphenols in postharvest technology [11, 12], chemistry and biochemistry [13][14][15][16], polyphenols and food [17][18][19][20][21], polyphenols and health [22][23][24][25][26][27][28]. From this short survey which takes into account only partly the last years, the great number and variety of researches on these plants metabolites can be pointed out.…”