Permeability phenolic compounds

Exposure to volatile stress signals such as ethylene and jasmonic acid can induce the synthesis and accumulation of high levels of phenolic compounds. The effect is not readily apparent because the accumulated phenolic compounds remain sequestered in organelles within the induced cells. However, increased membrane permeability resulting from even a minor injury or stress can result in levels of discoloration that are abnormally high for that cultivar. 

Roberts, J.R., DeFrietas, A.S.W., and Bidney, M.A.J. Influence of lipid pool size on bioaccumulation of the insecticide chlordane by northern redhorse suckers (Maxostoma macrolepidotimij, J. Fish. Res. Board Can., 34(l) 89-97, 1977. Roberts, M.S., Anderson, R.A., and Swarbrick, J. Permeability of human epidermis to phenolic compounds, /. Pharm. Pharmaa, 29 677-683, 1977. 

Roberts MS, Anderson RA, Swabrick J. 1977. Permeability of human epidermis to the phenolic compounds. J Pharm Pharmacol. 29 677-683. 

Phenolic compounds naturally occurring in plants have induced many physiological responses that duplicate those reported for ozone and/or peroxyacetylnitrate (PAN). Chlorogenic acid is a competitive inhibitor of lAA-oxidase (35) and plant growth is adversely affected by increased concentrations of auxins (36). Concentrations of chlorogenic acid are increased in tobacco tissue exposed to ozone ( ) Phenols inhibit ATP synthesis (37), oxidative phosphorylation ( ) and SH enzyme activity (27) they increase respiration (38), reduce CO2 fixation (22), modify both membrane permeability (40) and oxidation rate of reduced NADH... 

Definition. Some confusion exists even in the definition of tannin included under this name are many substances of varying structure, but having the common ability to transform fresh hides into rot-proof and barely permeable leather. The phenolic nature of these substances has often caused confusion between tannins and phenolic compounds of plants. 

Eugenol, like other phenolic compounds, is a structurally non-specific drug. The pharmacological action is not directly subordinated to chemical structure, except to the extent that structure affects physicochemical properties, as adsorption, solubility, pKa, and oxidation-reduction potential, factors which influence permeability, depolarization of the membrane and protein coagulation [34],... 

Phenolic acids are known to alter photosynthetic and respiration rates, cause stomatal closure, reduce chlorophyll content, modify the flow of carbon into various metabolic pools, and alter nutrient uptake in affected tissue (61-73). A common denominator for these multiple effects appears to be the action of phenolic compounds on membranes. They are soluble in membranes, and cause a reduction in ion accumulation in cells (71-73). Several phenolic acids cause membrane depolarization, especially at low pH, increasing membrane permeability to ions (72,73). This action undoubtedly impairs the proton gradient and ATP-driven ion transport. Logically, the effects phenolic acids have on membranes could disturb the water balance and mineral nutrition of seedlings, and research in my laboratory has established such a relationship. 

The permeability of the human epidermis to many phenolic compounds correlates with their lipophilic pattern. However, phenolic compounds appear to produce denaturation in the skin, and an additional increase in permeability is attributed to the resulting damage to the epidermis. Complications of topical phenol, notably cardiac dysrhythmias, including death, can be caused by phenol face peels (10). 

Aldehydes can be condensed with materials such as phenols or alcohols to form gels. The history of condensation of formaldehyde with phenol dates back to 1872 by Adolf Baeyer. Later (1910), Leo H. Baekeland used this reaction to produce a product which he named Bakelite. The condensation reactions of formaldehyde with phenolic compounds have recently been used for diversion of flow from high permeability regions in porous... 

Several mechanisms have been proposed to explain the antimicrobial properties of tannins. The antimicrobial effects of phenolic compounds are probably related to the inhibition of bacterial enzymes, alterations in cell wall permeability, an increase in the hydrogen ion activity of the microbial environment, a reduction in the surface and/or interfacial tension and perhaps chelation of essential minerals, particularly iron with a concomitant impairment of the microbial oxidative metabolic system (Chung et al. 1998). The antimicrobial activities of tannins are ascribed to the interactions of goats tannins with the extracellular enzymes secreted and... 

Two hypotheses have been proposed to explain how phenolic acids directly increase membrane permeability. The first is that the compounds solubilize into cellular membranes, and thus cause a "loosening" of the membrane structure so that minerals can leak across the membrane (28-30, 42). Support for this hypothesis comes from the fact that the extent of inhibition of electrical potentials correlates with the log P (partition coefficient of a compound between octanol and water) for various benzoic and cinnamic acid derivatives (Figure 5). 

The occurrence of coma, death, and systemic effects in two humans dermally exposed to cresols (Cason 1959 Green 1975) indicates that these compounds can be absorbed through the skin. No studies were located that sought to quantify the rate or extent of absorption in intact humans. An in vitro study of the permeability of human skin to cresols found that these substances had permeability coefficients greater than that for phenol, which is known to be readily absorbed across the skin in humans (Roberts et al. 1977). 

For DNAPL vaporization to work, the soil material must be permeable enough for the vapor bubbles to rise to the top of the water table. DNAPL vaporization is not effective for some low-volatility compounds, such as dichlorobenzene, diesel fuel, naphthalene, phenol, trichlorobenzene, and trichloropropane, unless it is coupled with groundwater sparging. All information is from the vendor and has not been independently verified. 

Polymers. In combination with various metal salts, sorbitol is used as a stabilizer against beat and light in poly(vinyl chloride) (qv) resins and, with a phenolic antioxidant, as a stabilizer in uncured styrene—butadiene mbber (qv) compositions and in polyolefins (see He AT STABILIZERS Olefin polymers Rubber compounding). Heat-sealable films are prepared from a dispersion of sorbitol and starch in water (255). Incorporation of sorbitol in collagen films gready restricts their permeability to carbon dioxide (256). 

The permeability of the skin to a toxic substance is a function of both the substance and the skin. The permeability of the skin varies with both the location and the species that penetrates it. In order to penetrate the skin significantly, a substance must be a liquid or gas or significantly soluble in water or organic solvents. In general, nonpolar, lipid-soluble substances traverse skin more readily than do ionic species. Substances that penetrate skin easily include lipid-soluble endogenous substances (hormones, vitamins D and K) and a number of xenobiotic compounds. Common examples of these are phenol, nicotine, and strychnine. Some military poisons, such as the nerve gas sarin (see Section 18.8), permeate the skin very readily, which greatly adds to then-hazards. In addition to the rate of transport through the skin, an additional factor that influences toxicity via the percutaneous route is the blood flow at the site of exposure. 

Action on the plasma membrane is the first and most fundamental of the bewildering array of deleterious effects of the cinnamic and benzoic acids. They reduce the transmembrane electrochemical potential with the immediacy and extent of that action depending on the concentration and lipid solubility of the compound.35,37,45,60 Rate of uptake also is concentration and pH-dependent, with transfer into and across the membrane greatest with lower pH conditions and higher external concentrations.60 Phenolic acid-induced depolarization of membranes causes a nonspecific efflux of both anions and cations accompanying the increased cell membrane permeability, and these membrane effects correlate with an inhibition of ion uptake. The phenolic acids suppress absorption of phosphate, potassium, nitrate, and magnesium ions, and overall changes in tissue... 

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