Our recent studies nave shown that naturally occurring dietary plant phenols such as tannic acid, quern-tin, myricetin, and anthraflavic acid are capable of inhibiting polycyclic aromatic hydrocarbon (PAH) metab olism and subsequent PAH-DNA adduci formation in epidermis of SENCAR mice (M. Das, et al.. Cancer Res., 47:760-766,1987, and 47: 767-773, 1987). In this study these plant phenols were t...

Radical-scavenging antioxidants play crucial roles in the protection of unsaturated oils against autoxidation and, especially, edible oils rich in omega-3 because of their high sensitivity to oxygen. Two complementary tools are employed to select, among a large set of natural and synthetic phenols, the most promising antioxidants. On the one hand, density functional theory (DFT) calculations pr...

Adjusting the pH of water samples before performing solid-phase microextraction (SPME) analysis can be used to selectively extract organic acids (at pH 2) and bases (at pH 12). Sorption behavior of test organics is predictable based on the acid dissociation constant in water. In general, polyacrylate (PA) and Carbowax-divinylbenzene (CW-DVB) show substantially higher fiber/water sorption coeffi...

Electrochemical oxidation has been proposed as a remediation method for chlorinated phenols but is hampered by anode fouling. In this work we explore the mechanism of anode fouling by chlorinated phenols, compare structure vs reactivity for phenols differing in the extent of chlorination, and relate the efficiency of oxidation to the mechanism of oxidation at different electrode types. Linear s...

Orange peel molasses, a byproduct of juice production, contains high concentrations of phenols, including numerous flavanone and flavone glycosides, polymethoxylated flavones, hydroxycinnamates, and other miscellaneous phenolic glycosides and amines. Extensive fractionation of these phenols was achieved by adsorption, ion exchange, and size exclusion chromatography. Size exclusion chromatograph...

To estimate phenols and flavonoids, enzymic antioxidants in the leaves of Boerhaavia erecta (LBE). The sample was extracted with 0.1M phosphate buffer for the analysis of phenols, flavonoids and antioxidants. The total phenolic content and total flavonoids in LBE were measured using Folin-Ciocalteau and aluminium chloride colorimetric methods respectively. The activity of Superoxide Dismutase (...

We analyzed a 12,000-yr sediment core from Wien Lake, central Alaska, for a suite of phenolic products from CuO oxidation of lignin polymers and compared their composition with pollen data from the same core to assess lignin phenols as sedimentary biomarkers. Inferences of the gross taxonomic origin of sediment organic matter from lignin-phenol composition agree with vegetational reconstruction...

Nitration of phenol and various 4-substituted phenols with Cu(NO3)2.3H2O, Cu(NO3)2.3H2O/SiO2, 9H2O and Cr(NO3)2. 9H2O in different anhydrous organic solvents are investigated. High selectivity ratio of para vs ortho isomers has been observed. Mono- and dinitro compounds f...