Phenolic Antioxidant Activity Research Articles

Effect of Corn Oil and Casein on the Antimicrobial Activity of Phenolic Antioxidants

ABSTRACTSeveral inhibitory concentrations of butylated hydroxyanisole (BHA) and tertiary butylhydroquinone (TBHQ) were tested against five microorganisms in the presence of 0, 1.5, 3.0 and 4.5% (v/v) of a lipid, corn oil, or 0, 3, 6 and 9% (w/v) of a protein, casein. In all cases, casein depressed, but did not abolish, the antimicrobial activity of BHA. However, corn oil virtually eliminated the antimicrobial properties of lethal doses of BHA. In contrast, TBHQ was affected much less by the food components than BHA, retaining considerable antimicrobial activity in most cases except with Staphylococcus aureus.

On the antioxidant activity of phenols obtained by hydrogenation of eucalyptus diversicolor wood

The mixture of monomeric phenols obtained by hydrogenation of wood from Eucalyptus diversicolor was analysed by GLC and tested for lipid antioxidant activity, which was found to be 75% of that of 2-t-butyl-4-methoxyphenol (BHA). Butylation decreased antioxidant efficiency. Increased demethylation was observed at higher hydrogenation temperatures.

Antioxidants and stabilizers-XXXVI. The activity of phenolic antioxidants with substituents containing O, S or N atoms in the stabilization of polypropylene

The antioxidative activities of phenols derived from 2,6-di- tert. butyl-4-methylphenol (1) and 2,4-dimethyl-6- tert.butylphenol (and containing at position 4 or 2 to the hydroxyl group a substituent with the heteroatoms O, S or N) have been investigated. The highest activity was observed with the compounds of type (I) containing sulphur. The oxidation of isotactic polypropylene stabilized with all sulphur derivatives under investigation was clearly retarded even after the induction period.

Antioxidant activity of phenols as related to effects of substituent groups

SummaryAntioxidant activity in lard was exhibited by all phenols which had electron‐repelling groups in the 2 and 6 positions. No activity was shown by those which had electron‐attracting groups in these positions.The mechanism of antioxidant action of alkyl phenols in lard does not appear to differ from that of di‐ or polyphenols. A free phenolic group was shown to be essential, and spectral absorption studies after autoxidation did not reveal any evidence for a dimer of the alkyl phenol. The dimer, stilbene quinone, reported isolated from oxidized petroleum oil, disappeared quite rapidly when added to oxidizing lard.