抄録
The leaf-starch was isolated as the form of iodine-starch complex from tea extracted with hot 30% calcium chloride solution, the yield of purified starch being ca. 1 % (45.8g. starch' from 4.5kg. of fresh leaf).
Amylose, amylopectin and their middle fraction in tea leaf-starch were then fractionated principally by Schoch's method using n-butanolwater (1 : 7 by volume).
The peaks of visible absorption spectra, Xln ol, of their iodine-potassium iodide solution were 600 mlt in leaf-starch, 620 mit in amylose, 551 m, a in amylopectin, and 605 ma in middle fraction respectivly.
Moreover, the relations of the concentration of their solution to the optical density (E) at λmax HCLO4 were investigated to make clear the fundamental items about the fractional quantitative analysis of amylose, amylopectin and middle fraction in the tea leaf-starch.
The following relationships were obtained. Starch (mg.)=0.0973 E-0.0012 Amylose (mg.)=0.0597 E-0.0005 Amylopectin (mg.)=0.4527 E-0.0044 Middle fraction (mg.)=0.1452 E-0.0030
The quantitative determination of starch in the tea leaves, and the fractional determinations of amylose, amylopectin and middle fraction of the tea leaf-starch have been developed, the main procedure being as follows:
