The compositions and contents of anthocyanins of 14 red wine grape varieties or clones (Vitis vinifera)

Astract:【Objective】The content of anthocyanins in grape is influenced by many factors such as variety, climate, soil property and training system, but the composition and relative content of anthocyanins of different cultivars are mainly determined by genetic factors. Therefore, anthocyanins can be used as chemical fingerprints for distinguishing grape varieties.【Methods】In this study, 14 red wine grape varieties (clones) (V. vinifera) were used, including‘Cabernet Franc 409'‘Cabernet Franc 327'‘Dolcetto', ‘Merlot 343'‘Merlot 181'‘Malbec'‘Marselan'‘Montepulciano'‘Nebbiolo'‘Pinot Noir 115'‘Pinotage'‘Syrah 100'‘Syrah 525'and‘Tempranillo'grown in the Shangzhuang Experimental Station of China Agricultural University, Haidian district, Beijing, China. Samples were collected in September 10, September 15, September 25, and October 16, 2016, respectively. Three biological repeats were made for each va-rieties (clones) . The soluble solids in grape juice were measured by hand sugar meter, the p H was measured by p H meter. The titratable acid concentration of juice was determined by potentiometric titration.The compositions and contents of anthocyanins of the grape skins were determined by high performance liquid chromatography-mass spectrometry (HPLC-MS) . The contents of anthocyanins of different grape varieties (clones) were compared and analyzed by principal component analysis. The classification of the varieties was made by cluster analysis.【Results】A total of 21 anthocyanins were detected. The trend of the relative contents was malvidin-3-glucoside (Mv) > petunidin-3-glucoside (Pt) > deiphinidin-3-glucoside (Dp) , and the relative content of cyanidin-3-glucoside (Cy) was low. The content of anthocyanins of‘Syrah'was the highest.‘Pinot Noir 115'had the highest relative content of malvidin-3-glucoside while it did not have acylated anthocyanins.‘Tempranillo'had higher relative content of delphinidin-3-glucoside and petunidin-3-glucoside and‘Cabernet Franc'had the lowest value. The relative contents of acetylated and coumarylated anthocyanins were higher than that of caffeylated anthocyanins. The relative content of acylated anthocyanins of‘Malbec'and‘Syrah'was higher than that of other varieties (clones) .The acetylated anthocyanins of‘Cabernet Franc'and‘Nebbiolo'were the highest while the values of‘Dolcetto', ‘Malbec'and‘Tempranillo'were less than 20%. The coumarylated anthocyanins in different varieties were quite different.‘Malbec'had the highest coumarylated anthocyanin's proportion while the‘Montepulciano'had the highest caffeylated anthocyanins. The relative content of delphinidin-3-coumaryl glucoside was relatively low, and it was only found in‘Malbec'‘Syrah'and‘Tempranillo' (<0.4%) . Cyanidin-3-coumaryl glucoside was relatively high in‘Merlot'‘Syrah'and‘Tempranillo', and it was not detected in other varieties. 14 varieties (clones) could be divided into two categories by the cluster diagram of the relative content of anthocyanins. The first category included‘Pinot Noir 115'and‘Dolcetto', the second category includes‘Malbec'and other varieties.‘Syrah'‘Montepulciano'‘Nebbiolo'‘Merlot'‘Dolcetto'‘Cabernet Franc'‘Pinotage'‘Marselan'were classified to the same class. Among them, the distance between‘Cabernet Franc'and‘Merlot'was near, and‘Marselan'‘Pinotage'and‘Nebbiolo'were relatively close.‘Pinot Noir 115'and‘Dolcetto'were located in the first quadrant, while‘Montepulciano'and‘Tempranillo'in the second quadrant, ‘Nebbiolo'‘Pinotage'‘Malbec'and‘Syrah'in the third quadrant includes according to the results of the principal component analysis. The different clones of‘Merlot'and‘Cabernet Franc'were all located in the fourth quadrant.【Conclusion】Different varieties (clones) of grape differ significantly in anthocyanin contents and compositions of fruit skins. The classification of 14 wine grape varieties by principal component analysis was basically the same as that by clustering analysis. Anthocyanins can be used as chemical fingerprints for distinguishing red wine grape varieties (clones) .