The present description discloses a novel biologically active ingredient of manuka honey. Specifically, the present description discloses a compound represented by formula (AA). (In the formula, each of R1, R2 and R3 independently represents a hydrogen atom or an optionally substituted alkyl group having 1-4 carbon atoms； m represents an integer of 1-3； each of R4-m, R5-m and R6-m independently represents a hydrogen atom or an optionally substituted alkyl group having 1-4 carbon atoms； and each of R7, R8, R9 and R10 independently represents a hydrogen atom or an optionally substituted alkyl group having 1-4 carbon atoms.)
