THE STRUCTURE OF RED AND PURPLE ANTHOCYAN INS AND THEIR PRODUCTION INCOLORED TUBER FLESH OF DIPLOID POTATOES, SOLANUM-TUBEROSUM L

This study was undertaken to elucidate the biological properties and c hemical structure of anthocyanins in the colored tuber flesh of potato es that were derived from the cultivated diploids of Solanum phureja. These results may lead to a higher yield of functional pigments in pot ato breeding. The relative content of anthocyanin per one gram of fres h weight was determined by spectrophotometer at each maximal wavelengt h in McIlvaine buffer (pH 3.0) after extraction by methanol containing 1% trifluoroacetic acid. The relative content in tubers declined with enlargement of tuber during a growth stage. The coefficients of varia tion of the relative contents in each plant ranged from 40 to 58%. How ever, there was no difference among plants in the average content of a nthocyanins. The major anthocyanins from the red and the purple tubers were isolated and purified by column chromatography and TLC. The main anthocyanins in red and purple tuber were identified as 3-O-(6 beta-D -glucopyranosyl)-5-O-(beta-D-glucopyranosyl) pelargonidin and petunidi n by proton NMR, FAB-MS and HPLC, respectively.