Applications Application. Methyl 4-hydroxybenzoate has antimicrobial characteristics and is used as preservative in pharmaceutical formulations and cosmetics. It can be combined with other parabens like propyl 4-hydroxybenzoate or ethyl 4-hydroxybenzoate. Description Methylparaben is a 4-hydroxybenzoate ester resulting from the formal condensation of the carboxy group of 4-hydroxybenzoic acid with methanol. It is the most frequently used antimicrobial preservative in cosmetics.…