Caprylhydroxamic Acid performs superbly at neutral pH and has excellent efficacy of fungistatic agents. It is the only organic acid which can maintain unionized state in acid to neutral, strong inhibitory mold(A. Niger). It can also chelate with Fe2+ and Fe3+ excellently. Then, it can stop mold to get Fe. Caprylhydroxamic Acid has the best length (C8) of C chain to promote degradation of cell membrane structures, and it can take the place of traditional preservatives when applied to the cosmetic.