Isolation and Identification of Anthocyanins in the Fruit Peels of Starkrimson and Marx Red Bartlett Common Pear Cultivars and Their Bud Mutants

摘要

Anthocyanins and anthocyanidins were determined in 3 varieties of common pears ( Pyrus communis L.), Starkrimson, Clapps Favourite and Marx red Bartlett. The pigments were extracted from the fruit peel with 0.5% HCl in methanol and the extracts were hydrolysed and then applied on 3 mm cellulose paper chromatograms. The chromatograms were developed subsequently in one direction, using formic acid , hydrochloric acid, water (5:2:3) v/v), or n-Butanol-Acetic acid-Water (BAW) (4:1:5 v/v). There was only one anthocyanidin present, namely cyanidin (Cy), which was identified according to their R_f values, UV-vis and IT-IR spectrum. The results show that the analysed common pear varieties contained cyanidin rhaminosyl, Starkrimson mutant and Starkrimson wild type and cyanidin xylosyl, Clapps Favourite and Marx Red Bartlett. R_f values and spectral characteristics that were determined were compared to standards. The results obtained justify the conclusion that the compound responsible for the red pigmentation in pear fruit of the varieties analysed is a cyandin-glycoside.