CHARACTERIZATION OF SOYBEAN PROTEINS BY HPLC

Proteins extracted from five soybean cultivars were separated by rever sed-phase (RP) and size exclusion (SE) high performance liquid chromat ography (HPLC). A RP-HPLC method was developed that permits protein se paration of nondefatted flours from soybean clutivars. RP-HPLC showed that protein of these cultivars could be classified into two groups, o ne of which contained intermediate component peaks under identical con ditions. Genetically closely related cultivars exhibited only small di fferences in their RP-HPLC chromatograms. Size exclusion high performa nce liquid chromatography (SE-HPLC) resolved extracts of nondefatted f lours from various soybean cultivars into six common peaks which accou nted for 80 to 94% of the total peak area. Soybean cultivars were prim arily identified by the percent area of their fifth peak (fraction F5) which had the highest variability of the total peak area. Seed protei n of the cultivars was closely related with the area percent of peak F 2 (r = 0.91). SE-HPLC proved to be a rapid one step quantitative metho d with potential for assessing soybean cultivars on the basis of prote in content.