Ascorbic acid in cultured tissue of briar rose, Rosa rugosa Thunb.

Ascorbic acid synthesis was studied using suspension cultured cells from the fleshy portion of the fruit of the rose, Rosa rugosa Thunb. Cells cultured in the dark contained ascorbic acid at a level of 13 mg/100 g wet wt. This value increased several fold when the cells were grown under light. Ascorbic acid does not accumulate in the growth medium possibly due to its rapid oxidation. L-galactono-1,4-lactone was readily converted to ascorbic acid whereas L-gulono-1,4-lactone was used to a much lesser degree. D-glucose, D-fructose, D-galactose. D-glucurono-1,4-lactone and myoinositol did not stimulate increased ascorbic acid synthesis. Reducing the sucrose content of the medium reduced the ascorbic acid content of the cells without altering cell yield.