Desmutagenic Actions of Partially Fractionated Dialyzate of Spinach on Trp-P-2

Abstract

The aqueous dialyzate of spinach was partially fractionated to identify the desmutagenic principles on Trp-P-2 and the mode of desmutagenic actions of the fractions was examined. The dialyzate was separated into two major fractions of Pl and P 2 by a Sephadex G-100 gel filtration. The desmutagenic effect on Trp-P-2 toward Salmonella typhimurium TA 98 and TA 100 was found in the P 2 fraction. Pl fraction was lethal to Salmonella bacteria. P 2 fractions was separated into four major fractions (P 2-1, P 2-2, P 2-3 and P 2-4) by a Sephadex G-25 gel-filtration. Each fraction showed the desmutagenic activity, especially P 2-3 and P 2-4 fractions had higher desmutagenic activities. The desmutagenic activity of these fractions was retained after heating them at 100°C for 20min. These fractions were also desmutagenic toward benzo [a] pyrene and N-methyl-N'-nitroso-N-nitrosoguanidine. It was suggested that these fractions reacted with Trp-P-2 and S 9 mix to bring about the inhibition of mutagenicity of Trp-P-2. No killing and mutagenicity on TA 98 and TA 100 were observed in these fractions.