Search PubMed⌕ Search

Biomedical subjects

H Gershon

Publications and source records attributed to H Gershon.

At least 73 records · Page 4Linked to original sources
PubMed1977

Antifungal properties of 2-bromo-3-fluorosuccinic acid esters and related compounds.

Twelve esters (C1-C6) of erythro- and threo-2-bromo-3-fluorosuccinic acid and related compounds were tested for antifungal activity against Candida albicans, Aspergillus niger, Mucor mucedo, and Trichophyton mentagrophytes at pH 5.7 and 7.0 in the absence and presence of 10% beef serum in Sabouraud dextrose agar. At pH 7.0 in the presence of 10% beef serum, no consistent pattern in the fungitoxicity of the erythro- and threo-2-bromo-3-fluorosuccinate esters was seen. Increasing the length of the ester function affects fungitoxicity as follows: C2 greater than C1 greater than C3 greater than C4 greater than C5 greater than C6. The most fungitoxic compound in this study was threo-ethyl 2-bromo-3-fluorosuccinate (C. albicans, 14 mug/ml; A. niger, 30 mug/ml; M. mucedo, 9 mug/ml; T. mentagrophytes, 5 mug/ml). Due to the ease of dehydrohalogenation, the fungitoxicity of 2-bromo-3-fluorosuccinic acid esters may be the result of a mixture composed of the parent compound, the bromo- and fluorofumaric acid esters, and HF and HBr of which part may be formed extracellularly and part within the cell.

Antifungal Agents↗
PubMed1976

Antifungal activity of 4-substituted crotonic acid esters.

Twenty-three 4-substituted crotonic acid esters were tested for antifungal activity against Candida albicans, Aspergillus niger, Mucor mucedo, and Trichophyton mentagrophytes. For the analogues of the methyl ester containing substituents in the 4 position, the following order of fungitoxicity was observed: I greater than Br greater than Cl greater than CH3S greater than CH3O greater than F=H. Of the homologues of the esters of the 4-iodo and 4-bromo compounds which included methyl, ethyl, n-propyl, n-butyl, n-pentyl, and n-hexyl, ethyl 4-iodocrotonate was most toxic to the four fungi at pH 7.0 in the presence of 10% beef serum (C. albicans, 18mug/ml, A. niger, 40 mug/ml, M. mucedo, 5 mug/ml, T. mentagrophytes, 4 mug/ml). It is believed that the mechanism of fungitoxicity is due, in part, to a nucleophilic reaction involving SH-containing compounds. This is based on the correlation of fungitoxicity with the order of leaving groups in the nucleophilic reaction and the protection against the toxicity of the test compounds to the fungi by cysteine and glutathione.

Antifungal Agents↗
PubMed1976

Antifungal properties of alpha,omega-alkanedicarboxylic acids and their dimethyl esters.

Thirteen alpha, omega-alkanedicarboxylic acids (C2-C12, C14, and C16) and their dimethyl esters were tested against Aspergillus niger, Trichoderma viride, and Myrothecium verrucaria in Sabourauc dextrose agar at pH 4.0 AND 5.6. Toxicity to Canadida albicans, Trichophyton mentagrophytes, and Mucor mucedo was determined in the same medium at pH 5.6 and 7.0 in the absence and presence of 10% beef serum. The dicarboxylic acids possessed very poor to no antifungal activity against all six fungi. The fungitoxicity of the dimethyl esters to A. niger, T. viride, and M. verrucaria was C8 = C9 greater than C7 greater than C6 = C5 greater than C10 greater than C4 greater than C11 and to C. albicans, T. mentagrophytes, and M. mucedo C9 greater than C10 greater than C11 greater than C12 = C8 greater than C7 greater than C6 greater than C5 greater than C4 greater than C3. The fungitoxicity of the esters of fatty acids and alpha-omega-alkanedicarboxylic acids was influenced by chain length and not by the pH of the medium or the absence or presence of beef serum.

Animals↗
PubMed1975

Amino acid analogs. III: New syntheses of monomethyl- and monophenylglutamic acids.

Glutamic acid analogs containing 3- and 4-methyl and 2-, 3-, and 4-phenyl substituents were prepared. The 3- and 4-methyl- and 3- and 4-phenylglutamic acids did not inhibit Plasmodium berghei and were nontoxic to the host (mice) at 640 mg/kg. The five analogs in addition to 2-methlglutamic acid were inactive against Lactobacillus casei at 1000 mug/ml in a defined medium: against Escherichia coli, only 2-methylglutamic acid caused 27% inhibition at 10,000 mug/ml. All six analogs failed to inhibit Aspergillus niger, Aspergillus oryzae, Trichoderma viride, and Myrothecium verrucaria in a defined medium below 10,000 mug/ml.

Animals↗
PubMed1975

Reversal of fungitoxicity of 8-quinolinols and their copper (II) bischelates. I. Amino acids and related compounds.

The effect of amino acids and related compounds on the toxicity of 8-quinolinols and their copper (II) bischelates to Aspergillus oryzae (ATCC 1011) Was studied. None of the compounds tested except the thiol-containing compounds, cysteine, cysteamine, glutathione, and N-acetylcysteine reversed the inhibitory action of 8-quinolinol but not that of 5-iodo-8-quinolinol or bis (8-quinolinolato) copper (II). It appears that the mechanism(s) of fungitoxicity of 8-quinolinol is different from that of 5-iodo-8-quinolinol or bis(8-quinolinolato) copper (II.).

Acetylcysteine↗
PubMed1975

Fungitoxicity of 1,4-naphthoquinones to Candida albicans and Trichophyton mentagrophytes.

Twenty-one substituted 1,4-naphthoquinones and five 8-quinolinols and copper(II) chelates were tested for antifungal activity against Candida albicans and Trichophyton mentagrophytes. Compounds containing electron-releasing or weak electron-withdrawing groups in the 2 and 3 positions of the 1,4-naphthoquinone ring were the most active against C. albicans at pH 7.0 in the presence of beef serum in the following order: 2-CH3O = 2,3-(CH3O)2 greater than 2-CH3 greater than 2-CH3S greater than 2-NH2 greater than 2,6-(CH3)2. For T. mentagrophytes under the same conditions the inhibitory 1,4-naphthoquinones contained the substituents 2-CH3O greater than 2,3-(CH3O)2 greater than 2-CH2S greater than 2-CH3 greater than 2-CH3(NaHSO3) greater than 2-NH2 greater than 2-C2H5S, 3-CH3 greater than 2,6-(CH3)2 greater than 2,3-CL2 greater than 5,8-(OH)2.

Antifungal Agents↗
PubMed1973

Inactive enzyme molecules in aging mice: liver aldolase.

Evidence is presented that there is a considerable accumulation of inactive fructose-1,6-diphosphate aldolase (EC 4.1.2.7) in the liver of senescent mice. Liver aldolase was purified from 3-month-old mice and used to immunize rabbits. It was demonstrated with the monospecific antibody thus produced that the liver aldolase of young adult (3 month) and aged (31 month) mice are antigenically identical. With the antibody, inactive enzyme molecules (crossreacting material) in liver homogenate of old mice were detected. The liver aldolase of senescent mice had half as much active enzyme per mg of protein, as well as per antigenic unit, as did the liver aldolase of young adult mice. The accumulation of faulty enzyme molecules may be one of the causes of debilitation leading to senescence and death.

Aging↗
PubMed1973

Antifungal properties of 2-alkenoic acids and 2-bromo alkanoic acids.

The antifungal activity of homologous series of 2-alkenoic and 2-bromo alkanoic acids was determined against Aspergillus niger, Trichoderma viride, Myrothecium verrucaria, and Trichophyton mentagrophytes and compared with data on analogous alkanoic and 2-fluoro alkanoic acids. The fungitoxicity of all of the series of compounds was determined by chain length, pH of the medium, and presence or absence of adsorbents such as serum albumin. The order of toxicity on a molecular basis, by using a scale where the most active series is 1.0, is 2-bromo alkanoic acids (1.0) > 2-fluoro alkanoic acids (1.2) > alkanoic acids (1.4) > 2-alkenoic acids (2.5).

Antifungal Agents↗