PROBLEM TO BE SOLVED: To provide a new antimicrobial agent having high antimicrobial power.SOLUTION: The new antimicrobial agent comprises a propanediol mono-β-hydroxycarboxylic ester represented by formula (1) or (2) (wherein, R1 and R2 are each 5C-9C branched or non-branched saturated or unsaturated alkyl).COPYRIGHT: (C)2012,JPO&INPIT【課題】抗菌力に優れた新規な抗菌剤の提供。【解決手段】下記式(1)または下記式(2)(式中、R1およびR2は、ともに炭素数5~9の分岐または非分岐の、飽和または不飽和アルキル基を示す。)で表されるプロパンジオールモノβ-ヒドロキシカルボン酸エステル。【選択図】なし