PROBLEM TO BE SOLVED: To provide a novel hydroperoxide detection reagent that can catalyze the reductive reactions of lipid peroxide and fatty acid peroxide as well as hydrogen peroxide with an oxidation coloring chromogen, and a novel hydroperoxide reduction composition, a novel coloring reaction inducer and a novel lignin decomposer.SOLUTION: A hydroperoxide detection reagent has an activity of catalyzing reduction of hydroperoxide and/or and an activity of catalyzing oxidation of an oxidation coloring chromogen, and contains the following (a) or (b): (a) YjbI； and (b) a cell containing a nucleic acid encoding YjbI.SELECTED DRAWING: NoneCOPYRIGHT: (C)2020,JPO&INPIT【課題】酸化発色型色原体によって、過酸化水素だけでなく過酸化脂質、過酸化脂肪酸の還元反応も触媒することができる、ヒドロペルオキシドの新規検出用試薬、ヒドロペルオキシド新規還元用組成物、新規呈色反応誘導剤およびリグニン新規分解剤の提供。【解決手段】ヒドロペルオキシドの還元を触媒する活性および／または酸化発色型色原体の酸化を触媒する活性を有する、以下の(a)または(b)を含む、ヒドロペルオキシドの検出用試薬；(a)YjbI、(b)YjbIをコードする核酸を含む細胞。【選択図】なし
