施肥の違いによる栽培サラダナのラジカル捕捉活性の相違

抄録

Four different fertilizer solutions were tested: food waste was fermented by methane bacteria to produce methane gas and give solution; this solution A was passed through a membrane filter to produce a filtrate and give solution B; swine waste-water was treated by activated sludge to give solution C; and a standard nutrient solution produced by Otsuka Chemical Co. gave solution D. Leaf lettuce (Saradana), a cultivar (Lactuca sativa L.) was cultivated with these four fertilizer solutions. The total polyphenol content determined by the Folin reagent and the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity evaluated by measuring the decrease of DPPH detected by its absorption at 517 nm were measured in leaf lettuce cultivated with each of these four fertilizer solutions. Lettuce leaves cultivated by fertilizer solutions, A, B, C, and D, were extracted by 80% ethanol, the order of total polyphenol content being A<C<D<B, and that of DPPH radical-scavenging activity being C<A<D<B. These results indicate significantly different effects of the fertilizer solutions on the total polyphenol contents and DPPH radical-scavenging activity.