Hexylresorcinol Research Articles

51410 A Novel Combination of Niacinamide, Hexyl Resorcinol and Retinyl Propionate Provides Superior Anti-Aging Benefits in an 8-week Split-Face Study

51410 A Novel Combination of Niacinamide, Hexyl Resorcinol and Retinyl Propionate Provides Superior Anti-Aging Benefits in an 8-week Split-Face Study

Topical application of retinyl propionate, 4 hexyl resorcinol, and niacinamide reverses molecular and clinical features of ageing.

Topical tretinoin is the mainstay of treatment for photoageing, despite the risk of skin irritation. Cosmetic combination anti-ageing formulations may offer similar efficacy to tretinoin, while improving on tolerability. We aim to demonstrate facial appearance benefits of a novel triple-active cosmetic formulation containing 4-hexylresorcinol, retinyl propionate, and niacinamide and to identify transcriptomic biomarkers underpinning these benefits. A cosmetic prototype formulation containing 4-hexylresorcinol, retinyl propionate, and niacinamide was evaluated exvivo and in a clinical study. For exvivo experiments, the cosmetic formulation was applied for 3 days to healthy surgical discard skin from female donors aged 31-51 years, with tissues harvested for gene expression and histologic analyses. In the clinical study, females aged 47-66 years with moderate-to-severe overall visual photodamage on the face applied either topical 0.02% tretinoin or the cosmetic formulation to the face for 16 weeks and to forearms for 1 week, with forearm biopsies taken for gene expression analyses. Visual grading for facial photodamage and VISIA-CR images was taken throughout the clinical study. Safety was visually assessed during site visits, and adverse event monitoring was conducted throughout. Gene expression analyses in both studies revealed modulation of pathways associated with skin rejuvenation, with several genes of interest identified due to being implicated in ageing and differentially expressed following the application of the cosmetic formulation. Reversal of a consensus skin ageing gene signature was observed with the cosmetic formulation and tretinoin in the exvivo and clinical studies. Both the cosmetic formulation and tretinoin clinically improved the overall appearance of photoageing, crow's feet, lines, wrinkles, and pores. Adverse event reporting showed that the cosmetic formulation caused less skin irritation than tretinoin. In a double-blind clinical study, the novel triple-active cosmetic combination formulation improved the visual appearance of photoageing similarly to prescription tretinoin. The cosmetic formulation and tretinoin reversed a consensus gene signature associated with ageing. Together with adverse event reporting, these results suggest that the cosmetic formulation may be a well-tolerated and efficacious alternative to tretinoin for improving the visual features of photoageing.

Amylmetacresol/2,4-dichlorobenzyl alcohol, hexylresorcinol, or carrageenan lozenges as active treatments for sore throat.

Up to 80% of sore throats are caused by viruses. Several over the counter products are available which provide symptomatic, not causal relief. For such lozenges, containing the antiseptics and local anesthetics amylmetacresol (AMC) and 2,4-dichlorobenzyl alcohol (DCBA) or hexylresorcinol (HR), recently an additional virucidal effect was published. Therefore, we tested a set of Strepsils® lozenges, containing either HR (Max [#2]) or AMC/DCBA (Original [#3], Extra Strong [#4], Warm [#5], Orange and Vitamin C [#6], Sugar free Lemon [#7], Children/Strawberry [#8] and Soothing Honey and Lemon [#9]) for their antiviral efficiency against representatives of respiratory viruses known to cause sore throat: human rhinovirus (HRV) 1a, HRV8, influenza virus A H1N1n, Coxsackievirus A10, and human coronavirus (hCoV) OC43. The lozenges were tested head to head with Coldamaris® lozenges (#1), which contain the patented antiviral iota-carrageenan. None of the tested AMC/DCBA or HR containing lozenges shows any antiviral effectiveness against HRV8 at the tested concentrations, whereas all are moderately active against HRV1a. Only lozenge #5 shows any activity against hCoV OC43 and Coxsackievirus A10 at the tested concentrations. Similarly, only lozenge #3 is moderately active against influenza A H1N1n virus. The data indicates that neither the isolated effect of the active ingredients nor the pH but rather one or more of the excipients of the specific formulations are responsible for the antiviral effect of some of the AMC/DCBA or HR containing lozenges. In contrast, carrageenan-containing lozenges are highly active against all viruses tested. In another experiment, we showed that binding and inactivation of virus particles by iota-carrageenan are fast and highly effective. During the residence time of the lozenge in the mouth, the viral titer is reduced by 85% and 91% for influenza A virus and hCoV OC43, respectively. Carrageenan-containing lozenges are, therefore, suitable as causative therapy against viral infections of the throat.

Regulation of β-amylase activity by alkylresorcinols

The effects of two alkylresorcinols, namely, methylresorcinol (MR) and hexylresorcinol (HR), which are chemical analogues of the natural anabiosis factors of some bacteria, on the catalytic activity of β-amylase has been investigated. When water-soluble potato starch is used as a substrate, MR in a concentration ranging from 0.8 to 12.9 mmol/L raises the activity of β-amylase to 170%. HR at a concentration ranging from 0.05 to 0.35 mmol/L stimulates a weak increase in the activity of β-amylase to 115%. A further increase in the concentration (0.75 mmol/L) leads to inhibition by 50%. The interaction of MR with β-amylase allows one to increase the general yield of the hydrolysis products of potato and malt starch by 1.5 to 1.6 times, to enhance the rate of hydrolysis by 4 to 5 times, and to extend the temperature and pH ranges of catalysis. Non-competitive activation in the presence of MR and non-competitive inhibition in the presence of HR are observed upon determining the kinetic parameters of the starch hydrolysis by β-amylase modified with alkylresorcinols.

The effect of alkylhydroxybenzenes on the antigen-binding capacity of antibodies

The effect of the chemical analogues of microbial extracellular autoregulators belonging to alkylhydroxybenzenes (AHB), hexylresorcinol (HR), and methylresorcinol (MR), on the interactions between specific antibodies and the corresponding antigens was studied. Nonlinear dependency of the inhibition of binding of AHB-modified antibodies on the AHB chemical structures and concentrations was revealed by enzyme immunoassay. Hexylresorcinol was shown to decrease the antibody affinity and avidity indices and simultaneously increase the indices of nonspecific binding of AHB-modified antibodies to antigens, thereby promoting the formation of “false” antigen-antibody complexes. The nonspecificity of the influence of AHB on the antigenbinding capacity of antibodies is an important characteristic of these effects, which allows us to consider AHB as unique “superhaptenes”.

Effect of, hexylresorcinol, a chemical analogue of bacterial anabiosis autoinducers on the stability of membrane structures

The effect of hexylresorcinol (HR), a chemical analogue of microbial anabiosis autoinducers of the alkylhydroxybenzene (AHB) group, on the stability of biological membranes and monolamellar liposomes formed of egg phosphatidylcholine (ePC) was studied. According to spectrophotometry and electron microscopy studies of HR-loaded liposomes in the presence of a surfactant Tween 20, the critical ratio between HR and ePC for liposome preservation was found to be close to equimolar. The trends in HR influence on membrane structural organization and stability of liposomes were also confirmed in experiments on intact bacterial cells explaining non-species-specific effect of AHBs. The demonstrated high efficiency of AHB biocides may be used in material and equipment protection against biocorrosion.

Influence of chemical analogues of microbial autoregulators on the sensitivity of DNA to UV radiation

We established that chemical analogues of alkylhydroxybenzenes (AHB), belonging to alkylresorcinols and functioning as microbial autoregulatory d1 factors, enhance the UV resistance of various DNA molecules of different origin and conformation. These include the linear DNA of the lambda phage, bovine spleen DNA, and the DNA of the pUC19 plasmid that is composed of a number of annular (supercoiled and relaxed) and linearized molecules. Irradiating DNA with UV light (lambda = 254 nm) in the presence of methylresorcinol (MR) or hexylresorcinol (HR) results in comparatively insignificant DNA destruction as evidenced by our data on the electrophoretic mobility pattern in agarose gel. Using the linear Hind III restricts of the lambda phage DNA, we revealed that the protective effect of AHB varies depending on their chemical structure (it is more manifest with HR than MR) and concentration. Importantly, the effect of HR on bovine spleen DNA was based on its protective activity and manifested itself after a long incubation period. Studies using the pUC19 plasmid demonstrated that AHB, apart from increasing the resistance of linearized DNA molecules to UV irradiation, prevented both the supercoiled annular-supercoiled relaxed and the supercoiled relaxed-linearized transitions. The possible mechanisms of the UV-protective effect of AHB on DNA and their contributions to the resistance of dormant microbial forms to environmental factors are discussed.

Biological Activity of the Essential Oil ofPiper betleL.

ABSTRACT The essential oil from the leaves of Piper betle L. Sagar Bangla cultivar has been found in vitro to be highly active against the growth of four keratinophilic fungi, Arthroderma benhamiae, Microsporum gypseum, Trichophyton mentagrophytes, Ctenomyces serratus and five pathogenic Aspergilli. Bacterial organisms Bacillus subtilis, B. pumilus, Staphylococcus aureus, Salmonella typhi and Vibrio cholerae were also found to be susceptible to the oil. The essential oil was also found to be more effective against tapeworms (Taenia solium) and hookworms (Bunostomum trigonocephalum), than the synthetic anthelmintics piperazine phosphate and hexyl resorcinol. The results presented lend some credibility to some of the reported applications of Piper betle in the Indian system of medicine.

Microbial Deterioration of Petroleum Products and their Prevention by Toxic Inhibitors

Summary One of the great problems in keeping petroleum products is their degradation by microorganism, particularly fungi, actinomycetes, and bacteria. In the presence of these microorganisms, in combination with organic materials and other impurities, are formed sludges. Petroleum products, especially those used in jet fuels, are required to be completely free from water and microbial sludges. The preferable microbial inhibitors, used in keeping petroleum products, are: 2,4-dimethoxy benzaldehyde, bromoacetic acid, dimethylamine borane, ethyldidene diacetate, tri-n-butyl borate, sodium tetraborate, sulphanilamide, iso-butyl, resorcinol, amyl resorcinol, hexyl resorcinol, octyl resorcinol p-chloro-m-cresol, salicylanilide, 2,4,5-trichlorophenol, 2,4,6-trichlorophenol, 3-methoxy propionaldehyde, 2-bromo-ethyl-l,2-propanediol or mixtures of these microbial inhibitors. Beside the addition of microbial inhibitors, tanks used in keeping petroleum products must be clean and furnished iniside with an inert material. Tanks are preferably kept in places of low relative humidity in order to avoid water.

Light driven scattering changes and increased 515 nm absorbance changes associated with fatty acid inhibition of photosynthesis in chlorella

1. The size and time of half decay of the 515 nm positive and 475 nm negative light driven absorbance changes in Chlorella was considerably increased by 1 · 10 −4–5 · 10 −4 M lipoic, caprylic and iodoacetic acids and by 1 · 10 −5–8 · 10 −5 M nitrous acid. Salts of these acids at neutral pH, iodoacetamide and HCl did not affect the absorbance changes. 2. The absorbance changes were restored to their original size and photosynthetic CO 2 fixation partially restored on washing the cells free of lipoic acid. 3. Light driven absorbance changes at 350 nm (positive), 405 nm, 425 nm, 450 nm and 648 nm (all negative) were unchanged in magnitude on addition of acid but their decays were slowed. The greater part of the 515-475 nm changes is therefore not due to Chlorophyll b. 4. Addition of 10 −3 M caprylic, lipoic, iodoacetic acids, methyl octonoate and hexyl resorcinol caused slow reversible light driven scattering changes which were not associated with volume changes of the whole cell.

Aerial disinfection with hexyl resorcinol in a monkey house.

1. The literature concerning respiratory infections and especially tuberculosis in monkeys, is reviewed. 2. Fourteen years experience using hexyl resorcinol aerosols (Aerovap, Ireland, Ltd.) in the Monkey House of the Dublin Zoological Gardens is recorded. 3. During this period, in contrast to experience elsewhere, only five cases of tuberculosis have occurred. 4. Other respiratory infections have not been a problem in spite of ample opportunities for visitors to the house to infect the animals. 5. No clinical or histological ill-effects of the constant breathing of hexyl resorcinol vapour over a period of years have been observed. 6. In the light of the satisfactory results obtained it is suggested that interest in air disinfection should be revived.

The epidemiology of the common cold. III. The effect of ventilation, air disinfection and room size.

Mechanical ventilation at 7 air changes/hr., air disinfection using vaporized hexyl resorcinol or α-hydroxy-α-methyl butyric acid, or irradiation of the air of the room above 8 ft. with ultraviolet radiation when applied to various clerical offices did not result in any observed alteration in the numbers of colds experienced by those working in them.There were no differences in the numbers of colds experienced by those working in rooms of different sizes. The working population in these rooms varied from, about 20 to more than 80.We should like to express our thanks to the Ministry of Pensions and National Insurance and to the Shell Petroleum Company, to those members of their staffs and to the nurses and others who helped us in this investigation. We should also like to thank the Shell Petroleum Company for the supply of α-hydroxy-α-methyl butyric acid, and the British Thomson Houston Company of Rugby for the loan of the ultraviolet lamp fittings.

A Contribution to the Study of Hookworm Disease in Infants.

Fourteen cases of serious hookworm disease in infants (0 to 18 months old) are studied, in an effort to analyse the unsatisfactory results obtained with the therapy we had been using. The clinical aspects and laboratory analysis results are discussed. The results given by tethrachlorethylene and hexylresorcinol crystoids as anthelmintic are compared. Heavy doses of hexylresorcinol given orally have proved to be superior to other drugs as anthelmintics in infants. The good tolerance and apparent non toxicity of the substance are stressed. Good results are reported with a treatment including hexylresorcinol, transfusions, iron therapy, a well balanced diet and psychotherapy, regarding the general condition of the child and its blood values. With this treatment we obtained an important shortening of the period of hospitalization in serious forms of hookworm disease in infants. For the first time we can report a fully satisfactory condition on release of children hospitalized with this disease.

Observations on the bactericidal action of hexyl resorcinol aerosols.

The bactericidal action of hexyl resorcinol vapour on airborne clouds of a variety of micro-organisms including pathogens and a virus has been investigated. In addition to killing rates comparable with those found by previous investigators, a phenomenon, which we have called the initial kill, has been demonstrated and experiments carried out to explain its mechanism. Under certain circumstances it enhances the elimination of viable bacteria very substantially.We are indebted for technical assistance to Corporal J. C. G. Harris, R.A.F., to Messrs B. F. Courtnay and C. M. R. Pitman, and to members of the Virus Research and Field Trials Sections.

Lipase-catalysed condensation of fatty acids with hydroxylamine

A lipase-catalysed condensation of fatty acid and hydroxylamine is described. Reaction in liver extracts follows the inhibition pattern of liver lipase, hexyl resorcinol and fluoride acting as powerful inhibitors. On fractionation of hog liver extract, the esterase and condensation activities remain associated. An analogous reaction is found with pancreatine. The condensation with hydroxylamine on lipase occurs only with relatively high concentrations of hydroxylamine and the reaction is further enhanced by increase of the fatty acid concentration. To obtain considerable hydroxamic acid formation, the concentration of 0.4 to 0.6 molar of hydroxylamine is required. With liver esterase, the chain length optimun is found with octanoate, while pancreas lipase reacts little with compounds containing below 8 carbons, and shows optimum activity with dodecanoate. The observations indicate that a relatively small change of free energy occurs with condensation of fatty acids with hydroxylamine to form hydroxamic acid. For the determination of the hydroxamic acid of long-chain fatty acids, a 50% alcoholic medium is required because of the water insolubility of this compound. The hydroxamic acid determination was modified for 50% ethanol-water.

Mr. G. S. W. Marlow

GEORGE STANLEY WITHERS MARLOW, whose death occurred on March 5, was born in 1889, and educated at New College Choir School, Oxford, and King‘s College, University of London. He graduated B.Sc. in 1909, and the next year obtained his associateship of the Institute of Chemistry, taking as his special subject, food and drugs. The F.I.C. (now F.R.I.C.) followed in 1913. For a couple of years after graduating, he was assistant to Mr. E. Hinks, public analyst for the County of Surrey. In 1911, he joined the staff of the Government Chemist, where he remained until 1919, when he became assistant secretary of the Institute of Chemistry. After six years there, he left to become personal assistant to Mr. W. J. U. Woolcock, general manager of the Association of British Chemical Manufacturers. Meanwhile, in 1923, he had been called to the Bar, and decided to practise in 1927. He was a member of Gray‘s Inn, and pupil to the late Mr. W. Trevor Watson, K.C. He acted in such cases of chemical patents as arose, his first being the application of Boots Cash Chemists, Ltd., to revoke Sharp and Dohme in the matter of hexyl resorcinol.

The effect of surface-active substances on the penetration of hexyl resorcinol into Ascaris lumbricoides var. suis

Although a Surface-active substance such as bile salt or soap penetrates the pit round worm only extremely slowly, yet it can markedly influence the penetration of hexyl resorcinol when present together. Keeping the hexyl resorcinol concentration fixed, low concentrations of soap bring about an acceleration, high concentrations complete inhibition. Interfacial tension measurements upon the soap/hexyl resorcinol mixtures suggest an explanation for this behavior. Addition of soap in low concentration increases the interfacial activity of the mixture, leading to an increased biological activity. Beyond a certain soap concentration micelles commence to form, and these micelles compete with the biological interface for the fixed amount of drug, reducing the rate and ultimately leading to complete inhibition. This suggested explanation appears to be applicable to other biological systems.

The biological activity of phenolic compounds; the effect of surface active substances upon the penetration of hexyl resorcinol into Ascaris lumbricoides var. suls.

The effect of surface active substances (sodium cholate, sodium oleate and cetyl trimethyl ammonium bromide (C. T. A. B.)), upon the penetration of hexyl resorcinol into the pig round-worm ( Ascaris lumbricoides var. suis ) has been measured quantitatively, and parallel mea­surements carried out upon the interfacial activity of these solutions again staninert mineral oil. In all three cases a marked similarity of action, differing only in degree, was observed. Using a fixed hexyl resorcinol concentration (0∙025%) the soap in dilute solution accelerated the penetration of this drug, the maximum accelerations being in the order sodium cholate sodium oleate < C. T. A. B., but when present in high concentration the penetration was com­pletely inhibited. The soaps alone were found to penetrate Ascaris very slowly, if at all, the amounts taken up being reasonably explained on the basis of surface adsorption only. Measurement of interfacial tensions showed that the soap and hexyl resorcinol molecules associate at an interface, forming a labile complex of increased surface activity. Using a fixed drug concentration (0∙025% as above), the interfacial tension went through a minimum as the soap concentration was increased, ultimately rising to the value for the soap alone. Maximum interfacial activity (i. e. minimum interfacial tension), was found in all cases to occur at that soap concentration giving maximum hexyl resorcinol penetration into Ascaris , and was in the same order, viz. cholate ≪ oleate < C. T. A. B. The interfacial tension measurements also showed that this particular soap concentration corresponded to the onset of micellar aggregation of the soap molecules. From the interfacial tension data a simple explanation for the biological measurements can be suggested, which at the same time appears to explain a number of observations upon other biological systems, in particular the effect of soaps upon the bactericidal activity of phenols. This explanation suggests that the biological activity of hexyl resorcinol (as measured by its rate of penetration) is determined by the interfacial activity of the mixture, and that when soap micelles are present the drug distributes itself between the micelles and any other interface present (e. g. oil/water or Ascaris /water). The maximum biological activity thus occurs at the critical concentration for micelle formation, since this has maximum interfacial activity. At high soap concentrations the hexyl resorcinol is mainly held by the soap micelles, so that the biological activity is thereby diminished, ultimately to zero since the soaps alone penetrate so extremely slowly. In the case of C. T. A. B./hexyl resorcinol mixtures it has been possible, from physical data only, to calculate a theoretical curve for the biological activity which is in good agreement with experiment. The possible bearings of these conclusions upon in vivo activity of hexyl resorcinol as an anthelmintic, and upon drug action in general, are briefly mentioned.

Effect of Hexyl Resorcinol on Diffusion of Chloride and Sulfate Through Sintered Glass and Other Membranes

Effect of Hexyl Resorcinol on Diffusion of Chloride and Sulfate Through Sintered Glass and Other Membranes

Experiments on the mode of action of hexyl resorcinol as an anthelmintic

1. Hexyl resorcinol penetrates readily into Ascaris lumbricoides var. suis through the cuticle.2. The rate of penetration is roughly proportional to the concentration of the drug in the medium, and is not significantly affected by changes of pH. or oxygen tension and the presence of a number of other substances, including other drugs and certain nutrient substances.3. The rate of penetration is greatly decreased by gastric mucin and certain concentrations of bile salts and soaps.4. The rate of penetration of the drug is increased by certain concentrations of sodium oleate.