A novel thermotropic liquid crystalline polymers poly{3-benzylidene amino-4-hydroxybenzoic acid (3,4-BAHBA)-co-trans-4-hydroxycinnamic acid (4HCA: trans-coumaric acid)} (Poly(3,4-BAHBA-co-4HCA)), was synthesized by the thermal polycondensation of 4HCA and 3,4-BAHBA, which was synthesized by a reaction of 3-amino-4-hydroxybenzoic acid (3,4-AHBA) with benzaldehyde. When the 4HCA compositions of P...

The effect of three food preservatives, sorbic acid and methyl and butyl esters of p-hydroxybenzoic acid, on the protonmotive force in Escherichia coli membrane vesicles was investigated. Radioactive chemical probes were used to determine the two components of the protonmotive force: delta pH (pH difference) and delta psi (membrane potential). Both types of compound selectively eliminated delta...

Distribution of phenolic acids in the flowers of Althaea rosea var. nigra has been studied by 2D-TLC and HPLC methods. The phenolic acids occurring in these fractions have been identified as ferulic, vanillic, syringic, p-coumaric, p-hydroxybenzoic, p-hydroxyphenylacetic and caffeic acids. By means of the HPLC methods the contents of major phenolic acids were estimated. From among the phenolic ...

A free and liberated by acid and alkaline hydrolysis phenolic acids from the hips of fourteen species of wildly growing roses were identifed and determined using SPE RP HPLC method. Eleven major phenolic acids (gallic, protocatechuic, gentisic, p-hydroxybenzoic, vanillic, caffeic, syringic, p-coumaric, ferulic. p-hydroxyphenylacetic, salicylic) were quantitatively investigated. The amount of in...

In the framework of development green analytical chemistry, a silica gel (SG) coated with semi-penetrating network based on partially biosourced poly(ethersulfone) is studied for greener extraction process aromatic organic pollutants. An optimized composition (80% linear polymer (LP): isosorbide-based and 20% cross-linking agent (XP) type bismaleimide) leads to total adsorption selected polluta...

The enzymatic carboxylation of phenol and styrene derivatives using (de)carboxylases in carbonate buffer proceeded in a highly regioselective fashion: Benzoic acid (de)carboxylases selectively formed o-hydroxybenzoic acid derivatives, phenolic acid (de)carboxylases selectively acted at the β-carbon atom of styrenes forming (E)-cinnamic acids.