Gallotannin production in cell cultures ofCornus officinalis Sieb. et Zucc

Gallotannin mixtures composed of tri-, tetra- and pentagalloylglucoses were produced by callus and suspension cultures ofCornus officinalis Sieb. et Zucc. The content of the main tannin, 1,2,3,6-tetragalloylglucose, was 36 times that of the intact fruits. The other three tannins, 1,2,6-trigalloyl-glucose, 1,2,3,4,6-pentagalloyl-glucose, and 6-digalloyl-1,2,3-trigalloyl-glucose, were isolated and identified with the authentic specimens. The ratios of the amounts among these tannins were not changed much during the culture period, and by the differences in the combination of plant growth regulators in the medium. Tannin production was stimulated by 6-benzyladenine, whereas cell growth required 2,4-dichlorophenoxyacetic acid or 1-naphthaleneacetic acid. Light irradiation appears to have inhibited tannin production in the cell cultures.