The methyl ester of p-hydroxybenzoic acid
is found in many skin care products.
Among the analysed hydroxycinnamic acids, gallic and p-hydroxybenzoic acids
predominated, while among the derivatives of hydroxycinnamic acid it was ferulic, sinapic and coumaric acids.
Gallic acid, pyrogallol, protocatechuic acid, chlorogenic acid, p-hydroxybenzoic acid
, caffeic acid, mangiferin, epicatechin, p-coumaric acid, ferulic acid, ECG, CG, ellagic acid, rutin, quercetin, kaempferol, homogentisic acid, tannic acid, and vanillic acid were used as standards for HPLC analyses.
, vanillic acid, naringenin, apigenin, baicalein, catechin, and epicatechin were purchased from Chengdu Biopurify Phytochemicals Ltd.
Roots had a great amount of verbascoside, a known antioxidant, particularly in the extracts with the highest RSA, along with higher levels of ferulic, salicylic, rosmarinic, gallic and coumaric acids; leaves had higher levels of luteolin-7-O-glucoside, p-hydroxybenzoic acid
, vanillic acid, quercetin and epicatechin, and flowers had caffeic acid and catechin exclusively along with greater phenolic diversity, possibly conferring to each of these organs their specific properties.
The antioxidant and anti-inflammatory activities of the p-hydroxybenzoic acid
have already been described previously [50,51].
Total of 7 phenolic acids were quantified in cherrywine using available standards (gallic acid, protocatechuic acid, p-hydroxybenzoic acid
, gentisic acid, chlorogenic acid, caffeic acid, and p-coumaric acid).
Parabens are esters of p-hydroxybenzoic acid
used as antimicrobial preservatives, especially against molds and yeast, in cosmetics, pharmaceuticals, and in food and beverage processing.
Safety Assessment of esters of p-hydroxybenzoic acid
, hydroquinone, phenyl 4-hydroxybenzoate (HPB), 4,4'-isopropylidenediphenol (BSPA), and 2-naphthol (NPT) were purchased from Acros Organics (New Jersey).
In general, avenanthramide has shown a higher antioxidant level than each of the following typical cereal components: ferulic acid, gentisic acid, p-hydroxybenzoic acid
, protocatechuic acid, syringic acid, vanillic acid, vanillin and phytic acid.
Comparison of thedegradation of p-hydroxybenzoic acid
in aqueous solution by several oxidation processes.