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Evaluation of acrodontiolamide, a chlorinated compound produced by Acrodontium salmoneum de Hoog for cytotoxicity and antimicrobial activity.

A new antifungal compound has been isolated from the culture medium of Acrodontium salmoneum de Hoog. Its structure was previously elucidated and was named acrodontiolamide. However, this compound is not characteristically produced by the genus Acrodontium, it is rather a feature of one isolate of A. Salmoneum coming from the soil of the grotto of La Pierre Saint Martin (France). Production, purification, cytotoxicity and antimicrobial activities of acrodontiolamide are described. Concerning microorganisms, inhibitory activity seems to be specifically restricted to phytopathogenic and entomapathogenic fungi. Acrodontiolamide is not cytotoxic to either normal human cultured cells or tumor cells.

Animals↗

[Toxic pathology of the hepatocyte in histiotype culture. II--Effects of an organic chlorine compound: lindane. Effect of a foreign metabolizable substance and toxic effect].

Lindane or HCH is gamma-hexachlorocyclohexane, still used as an agricultural insecticide. Tests were carried out using primary cultures of chicken embryo hepatocytes at the 11th day of incubation, for a fixed period of 40 hours, using different concentrations of the substance. From 0.5 to 10 mumol/l, acid phosphatase fell significantly, without any other consequences being observed. From 25 to 50 mumol/l, there was a tendency to hypertrophy of the mitochondria, to hyperplasia of the granular and smooth endoplasmic reticulum, and of the Golgi system. Growth was unchanged and acid phosphatase decreased. From 75 to 125 mumol/l, these changes were accompanied by signs of cellular damage and there was marked autophagia. Growth was reduced and acid phosphatase greatly decreased. From 150 to 175 mumol/l, the lesions were markedly polymorphous and some indicative of impending cytolysis, in particular spiral tearing of the hyaloplasm. Growth was markedly impaired, whilst there was a paradoxal increase in acid phosphatase. In increasing concentration, L first had the effect of a metabolisable foreign substance, of the "phenobarbital" type, then a definite toxic action. Sensitivity of the individual hepatocytes differed.

Animals↗

Chlorination of bisphenol A in aqueous media: formation of chlorinated bisphenol A congeners and degradation to chlorinated phenolic compounds.

The chlorination of bisphenol A (BPA) in aqueous media was investigated in order to describe the degradation profile of this compound and the formation of chlorinated products. Aqueous solutions of BPA (approx. 1 mg/l) were chlorinated by sodium hypochlorite solution at room temperature and under weakly alkaline conditions. Chlorinated compounds were extracted with dichloromethane and determined by gas chromatography/mass spectrometry (GC/MS). BPA was consumed completely within 5 min of chlorination, when the initial chlorine concentration was 10.24 mg/l (molar ratio to BPA, 58.7). On the other hand, when the initial chlorine concentration was 1.03 mg/l (molar ratio, 6.56), 9.3% of BPA still remained after 60 min chlorination. Five chlorinated BPA congeners, 2-chlorobisphenol A (MCBPA), 2,6-dichlorobisphenol A (2,6-D2CBPA), 2,2'-dichlorobisphenol A (2,2'-D2CBPA), 2,2',6-trichlorobisphenol A (T3CBPA) and 2,2', 6,6'-tetrachlorobisphenol A (T4CBPA) were formed in the earlier stages of chlorination. Several chlorinated phenolic compounds, 2,4,6-trichlorophenol (T3CP), 2,6-dichloro-1,4-benzoquinone (D2CBQ), 2,6-dichloro-1,4-hydroquinone (D2CHQ), C9H10Cl2O2, C9H8Cl2O and C10H12Cl2O2, were also formed by further chlorination.

Benzhydryl Compounds↗

Reactions of aqueous chlorine and chlorine dioxide with model food compounds.

Chlorine and chlorine dioxide (ClO2), common disinfecting and bleaching chemicals used in the food industry, are potent oxidizing and chlorinating agents. Unfortunately, little is known about the nature of the reactions of chlorine with organic food constituents. This presentation reviews published information concerning the reactions of chlorine gas (Cl2[g]), aqueous chlorine, and ClO2 with model food compounds, the fate of chlorine during the chlorination of specific food products, and the potential toxicity of the reaction products. Fatty acids and their methyl esters react with chlorine with the degree of incorporation corresponding to their degree of unsaturation. Aqueous chlorine oxidizes and chlorinates lipids and amino acids much more readily than ClO2. Several amino acids are highly susceptible to oxidation and chlorination by chlorine compounds. Reactions of chlorine and ClO2 with several food products, including flour and shrimp, have also been characterized. In one model system, 99% of Cl2(g) either reacted with components of flour or was consumed by oxidation/chlorination reactions. The lipids extracted from the chlorinated flour contained significant amounts of chlorine. Exposure of shrimp to hypochlorous acid (HOCl) solution resulted in significant incorporation of chlorine into the edible portion. Although significant quantities of chlorine can be incorporated into specific model compounds and food products, the health risks associated with exposure to chlorinated organic products are unknown. Preliminary studies using the Ames Salmonella/microsome mutagenicity assay indicate that the reaction products from mixtures of aqueous chlorine and various lipids or tryptophan are nonmutagenic. Nevertheless, additional studies are warranted, so that the toxicological significance of these reaction products can be understood more fully.

Amino Acids↗

Valveless sampling of ambient air for analysis by capillary gas chromatography.

A method for the high resolution, high sensitivity analysis of polluted air for individual organic compounds is described. Samples collected from 50 mL of ambient air at 87 K (liquid argon) are injected without use of a valve into a silica capillary column which is then temperature programmed from -30 degrees C to 180 degrees C. Hydrocarbons (4 to 10 carbons) as well as carbonyl compounds, chlorinated compounds and terpenes can be identified and quantified. The detection limit, not strongly dependent on carbon number, is estimated to be 0.3 ppbc in a 50 mL sample. Use of small samples eliminates the need to remove water vapor, a procedure which might jeopardize sample integrity.

Air Pollutants, Occupational↗

Significance of MTD and other descriptors in lipophilicity models for chlorinated aromatic compounds.

The lipophilicity of chlorinated benzenes and 20 biphenyls has been modeled using the minimum topological difference method and MTD indices. The MTD descriptor has been optimized on its own or together with nCl (number of chlorine atoms per molecule), 2D- and 3D-descriptors such as van der Waals surface area and volume, solvent accessible surface area and solvent-accessible surface-bounded molecular volume, and the inter-planar angle of the substituted biphenyls. In lipophilicity models of chlorinated aromatic compounds the majority of descriptors, including MTD, contain essentially the information of nCl. MTD is a good lipophilicity descriptor of chlorinated aromatic compounds either alone or in association with other descriptors. For chlorobenzenes it gives r = 0.998, s = 0.069, F = 2281, and for the set of chlorinated biphenyls r = 0.974, s = 0.255, F = 338, a better result than gives the nCl descriptor (r = 0.967). The significance of MTD descriptor in different models is discussed. Beside nCl, the MTD index encodes ortho and para effects.

Benzene Derivatives↗

Chlorine-containing compounds produced during Dictyostelium development. Detection by labelling with 36Cl.

DIF-1 [Differentiation-Inducing Factor 1; 1-(3,5-dichloro-2,6-dihydroxy-4-methoxyphenyl)hexan-1-one] is a novel chlorinated signal molecule that induces stalk-cell differentiation during development of Dictyostelium discoideum. Here we introduce the use of the radioisotope 36Cl to label DIF-1 and other low-Mr chlorinated compounds produced during development. H.p.l.c. and t.l.c. were used to resolve the labelled compounds. We find the following. (1) At least 14 dialysable 36Cl-labelled compounds are released into the medium by cells labelled continuously through development with Na36Cl. (2) The compounds can be classified into two major groups according to their times of accumulation in development. The early group of compounds starts accumulating at the end of aggregation, co-ordinately with DIF-1; the late group is only made at the end of development, by mature fruiting bodies. There may also be an intermediate group made during culmination. (3) The early group of compounds has been identified as comprising DIF-1 and seven of its metabolites by co-chromatography with the authentic compounds. These metabolites had previously only been recognized in suspensions of living cells incubated with exogenous DIF-1. Their detection here, from cells undergoing normal development, suggests that endogenous DIF-1 is metabolized in normal development in much the same way as is DIF-1 added to cells in suspension. (4) The intermediate and late groups of compounds are not obvious DIF-1 metabolites. They may have some role unconnected with DIF signalling. (5) A group of 36Cl-labelled late compounds remain cell-associated after washing of the fruiting bodies, and these are greatly enriched in stalk, compared with spore, cells. (6) Other slime-mould species were labelled with 36Cl. All three tested, namely D. mucoroides, D. vinaceo-fuscum and P. violaceum, also produced chloro compounds. D. mucoroides produced DIF-1 by the criterion of h.p.l.c. co-elution with authentic DIF-1. A developmentally regulated metabolism of chlorinated compounds may therefore be widespread amongst slime moulds. To our knowledge, labelling with 36Cl in vivo has not been reported before and provides a powerful general method for investigating chlorinated compounds in diverse organisms.

Animals↗

[Experiment observations of the germicidal effects of disinfectants on Vibro cholerae of El Tor biotype in different water bodies].

OBJECTIVE: To study the germicidal effect of disinfectant on vibro cholerae of El Tor biotype in different water bodies and to set a guidelines for disinfection in the epidemic foci of cholera. METHODS: The suspension quantitative bactericidal test was used to examine the germicidal effects of four kinds of disinfectants, including Chlorine compound disinfectant, Indophor, Chlorine dioxide and Glutarldehyde, on vibro cholerae of El Tor biotype in waste water from residential areas and hospitals, and water from ditches, rivers and seas. RESULTS: When germicidal rate for Vibrio Cholerae of El-Tor biotype in the five different kinds of water bodies reached to 100% in five minutes, concentrations of Chlorine compound disinfectant, Indophor, Chlorine dioxide and Glutaraldehyde were 25.0-250.0 mg/L, 100.0-250.0 mg/L, 10.0-25.0 mg/L and 100-500 mg/L, respectively. CONCLUSIONS: Germicidal effects of the four kinds of disinfectants on Vibrio Cholerae of El-Tor biotype differed, and so did germicidal effect of each of the same disinfectant on it in the five different kinds of water bodies. Concentrations of disinfectants needed to disinfected waste water was higher than that to disinfect natural water.

Chlorine Compounds↗

[Biogenic organochlorine compounds--occurrence, function and ecological relevance].

Organic chlorinated compounds are of increasing interest due to their almost ubiquitous occurrence in the biosphere, their toxic and cancerogenic activity, and their environmental relevance. Despite the relatively high level of knowledge on anthropogenic chlorine compounds, knowledge about biogenic chlorine compounds is comparatively poor. This is astonishing because the quantity of natural emissions of particular organic chlorinated compounds into the ecosphere exceeds that from industrial production considerably. An overview of the occurrence, biosynthesis, and ecological significance of biogenic chlorine-containing organics is given in this article. Results of recent investigations on this topic are discussed and the natural elimination processes of organic chlorinated compounds presented.

Bacteria↗

Chemical changes of organic compounds in chlorinated water. XI. Thin-layer chromatographic fractionation of Ames mutagenic compounds in chlorine-treated 4-methylphenol solution.

The diethyl ether extract from an aqueous solution of 4-methylphenol after treatment with hypochlorite was mutagenic to the Ames Salmonella test strain TA100 in the absence of liver homogenate. Gas chromatography-mass spectrometry (GC-MS) showed the occurrence of, at least, twenty compounds in the extract: chloro-4-methylphenols, chlorohydroxy-4-methylquinones and chlorinated 4-methylphenol dimers. The diethyl ether extract was fractionated into several fractions by silica gel and polyamide thin-layer chromatography (TLC). The fractionated components were then examined for mutagenicity by means of Ames assays, and were identified by GC-MS. TLC fractionation of the extract revealed that the major components present in the extract are not mutagenic, but minor components (less than 4% of the total extract) are mutagenic. GC-MS analysis indicated the presence of chlorinated 4-methylphenol dimers in the fraction which exhibited the highest mutagenicity.

Chlorine↗

Use of lysis and recycle to control excess sludge production in activated sludge treatment: bench scale study and effect of chlorinated organic compounds.

The most widely used treatment system in the pulp and paper industry--the activated sludge--produces high quantities of sludge which need proper disposal. In this paper a modified activated sludge process is presented. A synthetic wastewater, prepared to simulate the effluent of bleached and unbleached pulp and paper plant wastewater, was submitted to treatment in a bench scale aerobic reactor. The excess sludge was lysed in a mechanical mill--Kaddy mill--and totally recycled to the aeration tank. In the first phase the synthetic wastewater, without the chlorinated compounds, was fed to the reactor. In the second phase increasing dosages of the chlorinated compounds were used. Total recycle of excess sludge after disintegration did not produce adverse effects. During the first phase average COD removal efficiency was 65% for the control unit, which operated in a conventional way, and 63% for the treatment unit, which operated with total recycle. During the second phase the COD removal efficiency increased to 77% in the control unit and 75% in the treatment unit. Chlorinated organics removal was 85% in the treatment unit and 86% for the control unit. These differences are not significant.

Bacteria, Aerobic↗

Worker exposure to chlorinated organic compounds from the activated-sludge wastewater treatment process.

The objective of this research was to investigate some of the potentially controlling factors influencing the atmospheric releases of volatile organic chlorinated compounds from the activated-sludge sewage treatment process. The field study was designed to evaluate the wastewater and airborne concentrations of six chlorinated compounds: hexachlorobicycloheptadiene (hex-BCH), heptachlorobicycloheptene (Hex-VCL), chlordene, chloroform (CHCl3), carbon tetrachloride (CCl4) and tetrachloroethylene (TCE). Analysis of samples consisted of saturating 5 mL aliquots with sodium chloride, extracting with an equal amount of petroleum ether (PE) and subsequent analysis using a gas chromatograph. The air samples collected on Chromsorb 102 were desorbed with 2 mL PE. The study revealed that the highest wastewater concentrations for the water-insoluble hex-BCH, hex-VCL and chlordene were found in the aeration basins, which suggests adsorption of these compounds to the biomass. The plant effluent wastewater concentrations were reduced because of airborne release and suspended solids separation in the clarifiers. In contrast, the wastewater concentrations for the more water-soluble CHCl3, CCl4 and TCE were significantly reduced in the aeration basins. This is because of aerial stripping at the grit-chamber weir. This study suggests that the water-insoluble compounds have prolonged aerial release from the aeration basins. The water-insoluble compounds adhere to the biomass, which is recycled through the plant. The aerial release of these water-insoluble compounds was enhanced by increased aeration rate but depressed by higher suspended solids concentrations.

Air↗

Estimation of adsorbed amounts of volatile chlorinated organic compounds to wet soil based on the properties of the compounds and soils.

The adsorption equilibriums of 7 volatile organic chlorinated compounds to 10 wet soils were investigated by continuous flow adsorption experiments. The adsorption equilibriums for the wet soils could be expressed by the Henry equation. The most part of the adsorbed amount existed on the organic substances in the soil, and the soil-water adsorption equilibrium constant could be estimated from the organic carbon content of the soil. The adsorption coefficient to the organic carbon of the chloroethylenes and chloroethanes could be expressed by the functions of the n-octanol/water partition coefficient, respectively. The adsorbed amounts could be estimated using equations relating the organic content and the water content of each soil, and the n-octanol/water partition coefficient and the Henry constant for the gas-water equilibrium of each compound. The estimated results agreed well with the measured data.

Adsorption↗

Triterpene Biosynthesis in the Latex of Euphorbia lathyris: Effect of Calmodulin Antagonists and Chlorinated Phenoxy Compounds.

Recognized calmodulin antagonists and chlorinated phenoxyalkylamines were tested as inhibitors of mevalonate incorporation into triterpenols and their fatty acid esters in a centrifuged pellet from the latex of Euphorbia lathyris. The calmodulin antagonists, chlorpromazine (II), fluphenzine, and trifluoperazine were good inhibitors; I(50) values for II and trifluoperazine were 150 and 55 micromolar, respectively. Inhibition by the phenoxyalkylamines increased with increasing chlorine substitution, and I(50) for 2-(pentachlorophenoxy)ethyl N,N-diethylamine (IX) was 35 micromolar. The calmodulin-stimulated phosphodiesterase catalyzed hydrolysis of cAMP was used as an assay to quantitate the calmodulin antagonism of the tested compounds. Compounds II and IX were calmodulin antagonists over a concentration range similar to their effective range in the biosynthesis of triterpenes. The antagonism of the chlorinated phenoxy compounds increased in parallel to their inhibitory effect upon triterpene biosynthesis.

Journal Article↗

Analysis of adsorption equilibrium of volatile chlorinated organic compounds to dry soil.

Adsorption is one of the main mechanisms of soil contamination by hazardous volatile chlorinated organic compounds. The adsorption equilibriums of six volatile organic chlorinated compounds to three dry soils were investigated using batch adsorption experiments. The adsorption equilibriums for the dry soils could be expressed by the Dubinin-Astakhov equation. The equation's parameters were analyzed with the characteristic values of the soils and compounds. No correlation between the values of the affinity coefficients, beta, and the molecular volume, Mv, was found. W(0) could be expressed by the functions of a pore volume of less than 10 nm, V(<10 nm), or the specific surface area, S. The adsorbed amount could be estimated using equations relating E(0), V(<10 nm) (or S), and beta. The predicted amounts agreed well with the measured data.

Adsorption↗

Transformation of chlorinated aliphatic compounds by ferruginous smectite.

A series of chlorinated aliphatic compounds (RCI, including carbon tetrachloride (PCM), 1,1,1-trichloroethane (TCA), 1,1,2,2-tetrachloroethane (TeCA), pentachloroethane (PCA), hexachloroethane (HCA), trichloroethene (TCE), tetrachloroethene (PCE), trichloronitromethane (chloropicrin, CP), and trichloroacetonitrile (TCAN)) was reacted with ferruginuous smectite (sample SWa-1 from The Source Clays Repository), SWa, in aqueous suspension under anoxic conditions. Compounds highly polarizable or sharing substituents that facilitate charge delocalization adsorbed faster by reduced (SWa-R) than by unaltered (SWa-U) clay, indicating stronger dipole--dipole interactions between the substituents and the clay surface and/or hydrating water molecules. The reduction of the clay accelerated RCI adsorption up to 100-fold. Incubations with SWa-R promoted RCI reduction (CP, TCAN) or dehydrochlorination (TeCA and PCA). The reduction of structural Fe catalyzes the transformation of RCI via Brønsted and Lewis-basic promoted pathways. This study indicates that oxidation state of the structural Fe in SWa greatly alters surface chemistry and has a large impact on clay-organic interactions.

Aluminum Silicates↗

Chlorinated organic compounds in urban air in Japan.

Air pollution by the principal chlorinated organic compounds chloroform, carbon tetrachloride, 1,1,1-trichloroethane, trichloroethylene and tetrachloroethylene was investigated over a period of approximately 1 year at 15 sites in an urban area. Each compound was detected in the range from approximately 0.1 to several ppb; the concentrations of these compounds, with the exception of carbon tetrachloride, were higher than their global pollution levels. The concentrations of 1,1,1-trichloroethane and trichloroethylene especially were very high in the industrial regions, and the concentration of tetrachloroethylene was very high in the industrial and commercial regions. Concentrations were low in spring and summer and high in fall, winter and the rainy season. The correlation between the reciprocal of wind speed and concentrations was found to be subject to seasonal variations. Intake of chlorinated organic compounds by man from the air was estimated from the data to be larger than the allowable intakes determined by WHO and EPA for drinking water.

Air Pollutants↗