Journal articles: 'Coprostanol'

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MARTINS, C. C., M. I. VENKATESAN, and R. C. MONTONE. "Sterols and linear alkylbenzenes in marine sediments from Admiralty Bay, King George Island, South Shetland Islands." Antarctic Science 14, no. 3 (September 2002): 244–52. http://dx.doi.org/10.1017/s0954102002000093.

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Selected sterols (coprostanol, epicoprostanol, cholesterol, cholestanol), stanone (5ßcoprostanone) and linear alkylbenzenes (LABs) were measured in the surface sediments near Ferraz station sewage outfalls, in Admiralty Bay, King George Island, South Shetland Islands. during the summer of 1997/98 using GC-FID and GC-MS. Total sterol concentrations varied between 0.21 and 10.4 μg g−1 dry sediment. Cholesterol was the major sterol at all sites, except at the sewage outfall, where coprostanol predominated. The concentration of coprostanol varied between 0.03 and 6.14 μg g−1 dry sediment, but the majority of the samples contained levels below 0.13 μg g−1 dry sediment. The parameters coprostanol+epicoprostanol in total sterols, coprostanol/epicoprostanol ratio versus % of cholesterol in total sterols and versus 5ß-coprostanone concentration were used to identify the sewage impacted locations in the study area. Only sites extending to 50m from the sewage outfall exhibited a sterol signal indicating sewage input. Total LABs varied from <0.60 to 11.8 ng.g−1 dry sediment with the maximum level at the sewage outfall. Faeces from different species of seals all contained large amounts of cholesterol and some 5ßcoprostanone. Relatively low levels of coprostanol and high levels of cholesterol observed in distant sites could be attributed to natural sources such as marine mammals.

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Reeves, A. D., and D. Patton. "Faecal sterols as indicators of sewage contamination in estuarine sediments of the Tay Estuary, Scotland: an extended baseline survey." Hydrology and Earth System Sciences 9, no. 1/2 (June 16, 2005): 81–94. http://dx.doi.org/10.5194/hess-9-81-2005.

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Abstract. Sterol ratios are used to identify sources, occurrence and partitioning of faecal matter in sediments of the Tay Estuary, Scotland. The 5β/(5α+5β) ratio is used to discriminate between sewage and biogenic sterol sources by comparing the concentrations of coprostanols to cholesterol plus coprostanols. This index shows unambiguous sewage pollution in the Invergowrie Bay area (values >0.7). The coprostanol/epicoprostanol index is used to differentiate between human and non-human faecal inputs. Ratios confirmed the primary source as human-derived faecal material. The coprostanol/cholesterol ratio was calculated in order to elucidate the contribution of different biogenic sources to the sedimentary sterol budget. Ratios of >1 clearly indicate faecal sterol sources. Invergowrie Bay displayed no sterol signature other than sewage. A biogenic source of cholesterol influenced total sterol concentrations upstream of the City of Dundee. Attention is directed to the potential role of density fronts in compartmentalization of faecal material in bottom sediments.

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Juste, Catherine, and Philippe Gérard. "Cholesterol-to-Coprostanol Conversion by the Gut Microbiota: What We Know, Suspect, and Ignore." Microorganisms 9, no. 9 (September 5, 2021): 1881. http://dx.doi.org/10.3390/microorganisms9091881.

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Every day, up to 1 g of cholesterol, composed of the unabsorbed dietary cholesterol, the biliary cholesterol secretion, and cholesterol of cells sloughed from the intestinal epithelium, enters the colon. All cholesterol arriving in the large intestine can be metabolized by the colonic bacteria. Cholesterol is mainly converted into coprostanol, a non-absorbable sterol that is excreted in the feces. Interestingly, cholesterol-to-coprostanol conversion in human populations is variable, with a majority of high converters and a minority of low or inefficient converters. Two major pathways have been proposed, one involving the direct stereospecific reduction of the Δ5 double bond direct while the indirect pathway involves the intermediate formation of 4-cholelesten-3-one and coprostanone. Despite the fact that intestinal cholesterol conversion was discovered more than a century ago, only a few cholesterol-to-coprostanol-converting bacterial strains have been isolated and characterized. Moreover, the responsible genes were mainly unknown until recently. Interestingly, cholesterol-to-coprostanol conversion is highly regulated by the diet. Finally, this gut bacterial metabolism has been linked to health and disease, and recent evidence suggests it could contribute to lower blood cholesterol and cardiovascular risks.

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Gérard, Philippe, Pascale Lepercq, Marion Leclerc, Françoise Gavini, Pierre Raibaud, and Catherine Juste. "Bacteroides sp. Strain D8, the First Cholesterol-Reducing Bacterium Isolated from Human Feces." Applied and Environmental Microbiology 73, no. 18 (July 6, 2007): 5742–49. http://dx.doi.org/10.1128/aem.02806-06.

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ABSTRACT The microbial community in the human colon contains bacteria that reduce cholesterol to coprostanol, but the species responsible for this conversion are still unknown. We describe here the first isolation and characterization of a cholesterol-reducing bacterium of human intestinal origin. Strain D8 was isolated from a 10−8 dilution of a fresh stool sample provided by a senior male volunteer with a high capacity to reduce luminal cholesterol to coprostanol. Cholesterol-to-coprostanol conversion by strain D8 started on the third day, while cells were in stationary phase, and was almost complete after 7 days. Intermediate products (4-cholesten-3-one and coprostanone) were occasionally observed, suggesting an indirect pathway for cholesterol-to-coprostanol conversion. Resting-cell assays showed that strain D8 could reduce 1.5 μmol of cholesterol/mg bacterial protein/h. Strain D8 was a gram-negative, non-spore-forming, rod-shaped organism identified as a member of the genus Bacteroides closely related to Bacteroides vulgatus, based on its morphological and biochemical characteristics. The 16S rRNA gene sequence of strain D8 was most similar (>99.5%) to those of two isolates of the recently described species Bacteroides dorei. Phylogenetic tree construction confirmed that Bacteroides sp. strain D8 clustered within an independent clade together with these B. dorei strains. Nevertheless, no cholesterol-reducing activity could be detected in cultures of the B. dorei type strain. Based on Bacteroides group-specific PCR-temporal temperature gradient gel electrophoresis, there was no correlation between the presence of a band comigrating with the band of Bacteroides sp. strain D8 and cholesterol conversion in 11 human fecal samples, indicating that this strain is unlikely to be mainly responsible for cholesterol conversion in the human population.

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Matusik, Jean E., George P. Hoskin, and James A. Sphon. "Gas Chromatographic/Mass Spectrometric Confirmation of Identity of Coprostanol in Mercenaria mercenaria (Bivalvia) Taken from Sewage-Polluted Water." Journal of AOAC INTERNATIONAL 71, no. 5 (September 1, 1988): 994–99. http://dx.doi.org/10.1093/jaoac/71.5.994.

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Abstract Coprostanol is a major fecal sterol in humans and may, therefore, be a good indicator of sewage-polluted waters. Some types of edible seafood, such as clams, that live in these waters may be contaminated with coprostanol. Coprostanol from clam tissue extracts had been previously quantitated by gas chromatography (GC). In the present work, capillary column GC was used to separate coprostanol, and electron ionization mass spectrometry was used to confirm its identity. Confirmation of identity of coprostanol at the 75 ng level was obtained by comparing the spectrum of the authentic standard with spectra of the clam tissue extract obtained under the same instrumental conditions. Various other compounds can be eliminated as potential interferences by virtue of either their different GC retention times or their spectra.

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Kriaa, Aicha, Mélanie Bourgin, Héla Mkaouar, Amin Jablaoui, Nizar Akermi, Souha Soussou, Emmanuelle Maguin, and Moez Rhimi. "Microbial Reduction of Cholesterol to Coprostanol: An Old Concept and New Insights." Catalysts 9, no. 2 (February 8, 2019): 167. http://dx.doi.org/10.3390/catal9020167.

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The gut microbiota plays a key role in cholesterol metabolism, mainly through the reduction of cholesterol to coprostanol. The latter sterol exhibits distinct physicochemical properties linked to its limited absorption in the gut. Few bacteria were reported to reduce cholesterol into coprostanol. Three microbial pathways of coprostanol production were described based on the analysis of reaction intermediates. However, these metabolic pathways and their associated genes remain poorly studied. In this review, we shed light on the microbial metabolic pathways related to coprostanol synthesis. Moreover, we highlight current strategies and future directions to better characterize these microbial enzymes and pathways.

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Costa, Renata Lima da, and Renato S. Carreira. "A comparison between faecal sterols and coliform counts in the investigation of sewage contamination in sediments." Brazilian Journal of Oceanography 53, no. 3-4 (December 2005): 157–67. http://dx.doi.org/10.1590/s1679-87592005000200006.

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In September 2002, nine sediment samples (0-2 cm) were collected from Botafogo Cove (southwestern part of Guanabara Bay) in order to compare the use of chemical (coprostanol) and biological markers (E. coli and total coliforms) in identifying faecal contamination. The values found (organic carbon - 6.0 to 64.8 mg g-1; coprostanol - 1.4 to 105 µg g-1; E. coli - < 30 to 2400 NMP/10g and total coliforms - 40 to 9300 NMP/10g) were similar to or even higher than those observed in other contaminated areas of Guanabara Bay. In stations close to the shoreline, both coprostanol concentration and bacteria count confirmed that domestic sewage had accumulated in the cove. Coprostanol concentrations were still relatively high in the stations furthest from contamination sources, although faecal material represented a smaller fraction of the total organic carbon originated by dilution in waters containing algae. Reduction was proportionately higher by virtue of the use of the colimetric assessment method. This result may be associated with the effect that environmental variables (light, salinity, temperature) may have on the survival of bacteria during transport and deposition of sewage particles. Consequently, based on these results, coprostanol may be considered the better indicator of the faecal contamination level in Botafogo Cove sediments.

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Bataglion, Giovana Anceski, Hector Henrique Ferreira Koolen, Rolf Roland Weber, and Marcos Nogueira Eberlin. "Quantification of Sterol and Triterpenol Biomarkers in Sediments of the Cananéia-Iguape Estuarine-Lagoonal System (Brazil) by UHPLC-MS/MS." International Journal of Analytical Chemistry 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/8361375.

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Sterols and triterpenols present in sedimentary cores from 12 stations along the Cananéia-Iguape estuarine-lagoonal system were investigated by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Ten sterols and three triterpenols were identified and quantified, indicating both natural and anthropogenic sources. The relative distributions of sterol and triterpenol showed that the study area is submitted to organic matter (OM) from the Ribeira de Iguape River, seawater, surrounding vegetation, and plankton production. The contribution of these sources depends on the region of the estuarine-lagoonal system and the depth of sediment. Regarding anthropogenic sources, only the samples submitted to freshwater flow from the Ribeira de Iguape River presented concentration of coprostanol higher than the threshold value and diagnostic ratios, coprostanol/(coprostanol + cholestanol) and coprostanol/cholesterol, that indicate moderate contamination by domestic sewage in that area of the estuarine-lagoonal system. Therefore, the approach used herein identified the OM sources and its transport along the Cananéia-Iguape estuarine-lagoonal system (Brazil), which is a complex of lagoonal channels located in a United Nations Educational, Scientific and Cultural Organization (UNESCO) Biosphere Reserve.

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Hoskin, George P., and Ruth Bandler. "Identification of Mammalian Feces by Coprostanol Thin Layer Chromatography: Method Development." Journal of AOAC INTERNATIONAL 70, no. 3 (May 1, 1987): 496–98. http://dx.doi.org/10.1093/jaoac/70.3.496.

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Abstract Existing methods for the identification of mammalian fecal particles in foods have not heen completely satisfactory because visual identification of small particles is difficult. In addition, identification of feces by determining the presence of fecal alkaline phosphatase is limited to specimens in which the enzyme has not been inactivated, and it does not work well with feces from herbivores. A new method has been developed which uses coprostanol as a fecal indicator. Coprostanol is a heat-stable sterol found in the feces of mammals and some birds. A hexane extract of the suspect particle is applied to the preadsorbent zone of a silica gel thin layer chromatography plate which has been impregnated with 5% phosphomolybdic acid in ethanol. The plate is developed in diethyl ether-heptane (55 + 45), heated, and examined visually for the presence of coprostanol. Amounts of rat feces as small as 0.15 mg and cow feces as small as 0.5 mg have been identified using this method.

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Hoskin, George P. "Identification of Mammalian Feces by Thin Layer Chromatography of Coprostanol: Collaborative Study." Journal of AOAC INTERNATIONAL 70, no. 3 (May 1, 1987): 499–501. http://dx.doi.org/10.1093/jaoac/70.3.499.

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Abstract Mammalian feces contain coprostanol (5β-cholestan-3/J-ol). In this study, 7 collaborators each tested 45 unknown specimens by a thin layer chromatographic method that uses coprostanol as an indicator of feces. The materials tested were 5 replicates each of 3 test portion sizes (0.5,1.0, and 5.0 mg) of cockroach excreta (negative), and cow and rat feces (both positive). Of 315 specimens tested, 261 (82.9%) were correctly identified; there were 5 false positives, 26 false negatives, and from 1 collaborator, 23 inconclusive results.

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Isobe, Kei O., Mitsunori Tarao, Nguyen H. Chiem, Le Y. Minh, and Hideshige Takada. "Effect of Environmental Factors on the Relationship between Concentrations of Coprostanol and Fecal Indicator Bacteria in Tropical (Mekong Delta) and Temperate (Tokyo) Freshwaters." Applied and Environmental Microbiology 70, no. 2 (February 2004): 814–21. http://dx.doi.org/10.1128/aem.70.2.814-821.2004.

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ABSTRACT A reliable assessment of microbial indicators of fecal pollution (total coliform, Escherichia coli, and fecal streptococcus) is critical in tropical environments. Therefore, we investigated the relationship between concentrations of indicator bacteria and a chemical indicator, coprostanol (5β-cholestan-3β-ol), in tropical and temperate regions. Water samples were collected from the Mekong Delta, Vietnam, during wet and dry seasons, and from Tokyo, Japan, during summer, the aftermath of a typhoon, and winter. During the wet season in the Mekong Delta, higher bacterial densities were observed in rivers, probably due to the higher bacterial inputs from soil particles with runoff. In Tokyo, higher bacterial densities were usually observed during summer, followed by those in the typhoon aftermath and winter. A strong logarithmic correlation between the concentrations of E. coli and coprostanol was demonstrated in all surveys. Distinctive seasonal fluctuations were observed, as concentrations of coprostanol corresponding to 1,000 CFU of E. coli/100 ml were at their lowest during the wet season in the Mekong Delta and the typhoon aftermath in Tokyo (30 ng/liter), followed by the dry season in the Mekong Delta and the summer in Tokyo (100 ng/liter), and they were much higher during the winter in Tokyo (400 ng/liter). These results suggested that E. coli is a specific indicator of fecal contamination in both tropical and temperate regions but that the densities are affected by elevated water temperature and input from runoff of soil particles. The concurrent determination of E. coli and coprostanol concentrations could provide a possible approach to assessing the reliability of fecal pollution monitoring data.

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Leeming, R., N. Bate, R. Hewlett, and P. D. Nichols. "Discriminating faecal pollution: a case study of stormwater entering Port Phillip Bay, Australia." Water Science and Technology 38, no. 10 (November 1, 1998): 15–22. http://dx.doi.org/10.2166/wst.1998.0369.

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This investigation was designed to provide preliminary information to the Environment Protection Authority concerning the input of faecal matter to stormwater drains in the Rippleside area of Geelong, Victoria. Results derived from the combined use of sterol biomarkers (e.g. coprostanol and 24-ethylcoprostanol) and four sub-groups of bacterial indicators (e.g. thermotolerant coliforms, E. coli, faecal streptococci and enterococci) indicated that during wet weather, all sites sampled were affected by significant human faecal contamination. Ratios of coprostanol to bacterial indicators were similar to those for samples collected from nearby sewer mains. During dry weather, there were still severely elevated levels of faecal contamination based on bacterial indicators, but correspondingly low concentrations of faecal sterols suggesting minimal human or herbivore faecal contamination. The origin of the majority of the faecal pollution in dry weather therefore remains to be fully explained. It is clear from this and related studies that the combined measurement of faecal sterols and bacterial indicators can greatly assist distinguishing sources of faecal pollution. It is also shown for aquatic environments that the measurement of coprostanol or other single indicators alone, is inadequate to fully discern faecal contamination from human sources.

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Bartlett, P. D. "Degradation of coprostanol in an experimental system." Marine Pollution Bulletin 18, no. 1 (January 1987): 27–29. http://dx.doi.org/10.1016/0025-326x(87)90653-9.

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Volkman, John K., Teresa O'Leary, Rhys Leeming, Peter D. Nichols, and John K. Volkman. "Assessment of the sources, transport and fate of sewage-derived organic matter in Port Phillip Bay, Australia, using the signature lipid coprostanol." Marine and Freshwater Research 50, no. 6 (1999): 547. http://dx.doi.org/10.1071/mf98051.

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To evaluate the distribution of faecal material in Port Phillip Bay, surface sediments from sites throughout the bay and inflowing water courses were analysed for fatty acids and sterols. Water samples were also collected to identify possible sources of faecal contamination. Bay sediments had total fatty acid concentrations between 4 and 183 µg g–1 (dry weight) and total sterol concentrations between 0.6 and 39.2 µg g–1. Creek sediments contained more sterols, ranging from 22.8–148 µg g–1. These lipid distributions suggest that the bulk of the labile organic matter derives from marine microalgae, primarily diatoms. Coprostanol (5β-cholestan-3β-ol), a sterol often used as an indicator of faecal contamination, was also present. Concentrations ranged from <0.01–0.55 µg g–1 in surface sediments, with values over 0.25 µg g–1 and 5β-/5α-C27 stanol ratios greater than 0.4, indicative of sewage inputs. A clearer picture of distributions of sewage-derived organic matter was obtained when coprostanol was normalized to total organic matter rather than sediment dry weight. Areas showing higher coprostanol concentrations included those adjacent to the main sewage treatment plant and several low-volume drains and creeks, indicating localized problems of sewage contamination.

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Bhattacharyya, A. K. "Differences in uptake and esterification of saturated analogues of cholesterol by rat small intestine." American Journal of Physiology-Gastrointestinal and Liver Physiology 251, no. 4 (October 1, 1986): G495—G500. http://dx.doi.org/10.1152/ajpgi.1986.251.4.g495.

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Coprostanol and cholestanol are two saturated analogues of cholesterol. The former, which is the A/B ring isomer of cholesterol, is a nonabsorbable sterol, whereas the latter, which has an A/B ring configuration closer to that of cholesterol, is absorbed only half as efficiently as cholesterol. Intestinal mucosal cell uptake and esterification, two important steps in absorption, were studied in vivo after feeding the sterols and in vitro using everted sacs of rat small intestine. The results showed that the intestinal tissue content of coprostanol, total and esterified, were significantly lower than that of cholestanol. Total cholesterol concentration in the intestinal tissue was similar throughout but the esterified cholesterol content increased significantly throughout the length of the intestine compared with controls. The study suggests that cholestanol is absorbable because its uptake and esterification are not limited, whereas coprostanol is nonabsorbable because its uptake and esterification are limited in the intestinal mucosa. Also, the two sterols stimulate the activities of cholesterol esterase, one of the cholesterol esterifying enzymes, in the intestinal mucosa. The present study along with previous studies suggests that the structure of the sterol molecule as a whole appears to be the important determinant for its uptake and esterification, and probably absorption, in the small intestine.

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Suprihatin, I., H. Fallowfield, R. Bentham, and N. Cromar. "Determination of faecal pollutants in Torrens and Patawalonga catchment waters in South Australia using faecal sterols." Water Science and Technology 47, no. 7-8 (April 1, 2003): 283–89. http://dx.doi.org/10.2166/wst.2003.0700.

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This research investigated faecal pollution by sterol profiling in two Adelaide metropolitan catchments in winter 2000 and summer 2001. Water was sampled from five sites on the River Torrens and two sites on Patawalonga river catchment. The steroids detected were coprostanol, epicoprostanol, cholesterol, cholestanol, stigmasterol, betasitosterol, and stigmastanol. The concentrations range from 5 ng/L (of coprostanol) to 34 μmg/L (of stigmasterol), with cholesterol detected more frequently at relatively high concentrations (approximately 2 μmg/L). Sterol profiling suggested two sites on two occasions may have been impacted by human faecal contamination. Other steroid profiles suggested that sources of pollution consistently included dogs and birds. The steroid concentrations in the Torrens catchment were higher in winter, however, this was not observed in the Patawalonga catchment.

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Wen, Xin, Yijuan Bai, Shurong Zhang, Aizhong Ding, Lei Zheng, and Jian Li. "Distributions and Sources of Sedimentary Sterols as well as Their Indications of Sewage Contamination in the Guanting Reservoir, Beijing." Journal of Chemistry 2020 (March 19, 2020): 1–11. http://dx.doi.org/10.1155/2020/3050687.

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In this study, domestic sewage contamination in the Guanting Reservoir, one of the major water source reservoirs of Beijing, was examined using sterols as tracing molecular markers. Nineteen sediment samples in seven cross-sections in the Guanting Reservoir were collected, extracted, and analyzed by gas chromatography-mass spectrometry (GC-MS). Seven different sterols were identified and quantified from the surface sediment samples in the Guanting Reservoir. The total sterols in sediments of the reservoir ranged from 2.78 μg g−1 to 40.31 μg g−1 with the average concentration of 13.53 μg g−1. Concentrations of fecal sterols, coprostanol and epicoprostanol in the Guishui River reservoir area were generally higher than in the Yongding River reservoir area. The average concentrations of coprostanol and epicoprostanol in the Yongding River reservoir area were 0.41 μg g−1 and 0.34 μg g−1, respectively. The average concentrations of coprostanol and epicoprostanol in the Guishui River reservoir area were 0.72 μg g−1 and 0.70 μg g−1, respectively. Ratios of sterols indicated higher sewage pollution in regions close to river mouths and reservoir banks. Principal component analysis (PCA) indicated three distinct sources of sterols from domestic sewage, phytoplankton, and terrestrial higher plants. This article identified the current situation of sewage contamination in sediments of the Guanting Reservoir, which could provide important references for further implementation of pollution control and basin management in the region.

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Bukiya, Anna N., Jitendra D. Belani, Scott Rychnovsky, and Alex M. Dopico. "Specificity of cholesterol and analogs to modulate BK channels points to direct sterol–channel protein interactions." Journal of General Physiology 137, no. 1 (December 13, 2010): 93–110. http://dx.doi.org/10.1085/jgp.201010519.

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The activity (Po) of large-conductance voltage/Ca2+-gated K+ (BK) channels is blunted by cholesterol levels within the range found in natural membranes. We probed BK channel–forming α (cbv1) subunits in phospholipid bilayers with cholesterol and related monohydroxysterols and performed computational dynamics to pinpoint the structural requirements for monohydroxysterols to reduce BK Po and obtain insights into cholesterol’s mechanism of action. Cholesterol, cholestanol, and coprostanol reduced Po by shortening mean open and lengthening mean closed times, whereas epicholesterol, epicholestanol, epicoprostanol, and cholesterol trisnorcholenic acid were ineffective. Thus, channel inhibition by monohydroxysterols requires the β configuration of the C3 hydroxyl and is favored by the hydrophobic nature of the side chain, while having lax requirements on the sterol A/B ring fusion. Destabilization of BK channel open state(s) has been previously interpreted as reflecting increased bilayer lateral stress by cholesterol. Lateral stress is controlled by the sterol molecular area and lipid monolayer lateral tension, the latter being related to the sterol ability to adopt a planar conformation in lipid media. However, we found that the differential efficacies of monohydroxysterols to reduce Po (cholesterol≥coprostanol≥cholestanol>>>epicholesterol) did not follow molecular area rank (coprostanol>>epicholesterol>cholesterol>cholestanol). In addition, computationally predicted energies for cholesterol (effective BK inhibitor) and epicholesterol (ineffective) to adopt a planar conformation were similar. Finally, cholesterol and coprostanol reduced Po, yet these sterols have opposite effects on tight lipid packing and, likely, on lateral stress. Collectively, these findings suggest that an increase in bilayer lateral stress is unlikely to underlie the differential ability of cholesterol and related steroids to inhibit BK channels. Remarkably, ent-cholesterol (cholesterol mirror image) failed to reduce Po, indicating that cholesterol efficacy requires sterol stereospecific recognition by a protein surface. The BK channel phenotype resembled that of α homotetramers. Thus, we hypothesize that a cholesterol-recognizing protein surface resides at the BK α subunit itself.

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Jeng, Woei-Lih, Joe Wang, and Bor-Cheng Han. "Coprostanol distribution in marine sediments off southwestern Taiwan." Environmental Pollution 94, no. 1 (1996): 47–52. http://dx.doi.org/10.1016/s0269-7491(96)00101-7.

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Venkatesan, M. I., and F. H. Mirsadeghi. "Coprostanol as sewage tracer in McMurdo Sound, Antarctica." Marine Pollution Bulletin 25, no. 9-12 (January 1992): 328–33. http://dx.doi.org/10.1016/0025-326x(92)90691-x.

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Liebezeit, Gerd, and Ralf Wöstmann. "Coprostanol in Siak River Sediments, E Sumatra, Indonesia." Bulletin of Environmental Contamination and Toxicology 85, no. 6 (November 16, 2010): 585–88. http://dx.doi.org/10.1007/s00128-010-0144-4.

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Makran, Mussa, Gabriel López-García, Guadalupe Garcia-Llatas, Reyes Barberá, Amparo Alegría, and Antonio Cilla. "Cytotoxic Effect of Cholesterol Metabolites on Human Colonic Tumor (Caco-2) and Non-Tumor (CCD-18Co) Cells and Their Potential Implication in Colorectal Carcinogenesis." Proceedings 70, no. 1 (November 9, 2020): 56. http://dx.doi.org/10.3390/foods_2020-07613.

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Unabsorbed cholesterol, along with that of bile secretions and flaked colon cells, can be metabolized by colonic microbiota. The generated metabolites have been proposed as promoters of colorectal cancer (CRC). In this study, the cytotoxicity (MTT assay) of the main commercially available cholesterol-derived metabolites (coprostanol, cholestanol, coprostanone, and cholestenone) on human colon cancer (Caco-2) and non-tumor (CCD-18Co) cells was evaluated at different physiologically relevant concentrations (9.4–300 µM) and incubation times (24–72 h). In general, the metabolites that most reduced cell viability were coprostanone (54–85% in Caco-2 and 20–81% in CCD- 18Co) and cholestenone (17–91% in Caco-2 and 14–81% in CCD-18Co). These two metabolites are the most hydrophobic, thus reflecting a possible relationship between hydrophobicity and cytotoxicity. Moreover, cholestenone (IC50 at 72 h: 5 ± 1 µg/mL) should be considered cytotoxic on CCD- 18Co cells (non-tumor cells) since it shows an IC50 close to the one considered toxic (<4 µg/mL). Furthermore, CCD-18Co cells are more vulnerable to the cytotoxic effect of cholesterol metabolites. Possible compensatory responses, attenuating the reduction in cell viability caused by cholesterol metabolites, were observed, however these reactions could favor inflammation, resistance to apoptosis, and cellular proliferation, likely contributing to the development of CRC. In conclusion, cholesterol metabolites, mainly the most hydrophobic, could act as promoters of CRC through their cytotoxic activity.

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Zgheib, S., M. C. Gromaire, C. Lorgeoux, M. Saad, and G. Chebbo. "Sterols: a tracer of organic matter in combined sewers." Water Science and Technology 57, no. 11 (June 1, 2008): 1705–12. http://dx.doi.org/10.2166/wst.2008.285.

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The important organic pollution of combined wet weather flows (WWF), its acute impact on receiving waters have been widely demonstrated. The main three possibly origins for this organic pollution are: runoff water (streets and roofs), wastewater and erosion of sewer sediments in combined sewer system. This work, for tracing the origin of organic particles bound in combined sewer system, has been focused on the innovative use of sterols. So, eight sterols have been selected and analysed for each kind of sample. Results are represented in contents of sterols (μg g−1) and in sterol profiles (%).The comparison of contents and profiles leads the separation between two groups: runoff water, characterized by the total absence of coprostanol, epicoprostanol and coprostanone, and the group of sewer deposits (gross bed sediment (GBS), organic layer (OL), biofilms) and wastewater. Moreover, sewer deposits and wastewater can be distinguished by their sterol contents and profiles. To evaluate their contribution to WWF a comparison between sterol signatures is done which shows that these effluents have a strong similarity in profiles and in contents of sterols to the organic layer.

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CHOI, Minkyu, Hyo-Bang MOON, Sang-Soo KIM, and Jong-Soo PARK. "Evaluation of Sewage Pollution by Coprostanol in the Sediments from Jinhae Bay, Korea." Korean Journal of Fisheries and Aquatic Sciences 38, no. 2 (April 1, 2005): 118–28. http://dx.doi.org/10.5657/kfas.2005.38.2.118.

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Florini, Styliano, Esmaeil Shahsavari, Arturo Aburto-Medina, Leadin S. Khudur, Stephen M. Mudge, David J. Smith, and Andrew S. Ball. "Are Sterols Useful for the Identification of Sources of Faecal Contamination in Shellfish? A Case Study." Water 12, no. 11 (November 2, 2020): 3076. http://dx.doi.org/10.3390/w12113076.

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This work aimed to identify the major source(s) of faecal pollution impacting Salcott Creek oyster fisheries in the UK through the examination of the sterol profiles. The concentration of the major sewage biomarker, coprostanol, in water overlying the oysters varied between 0.01 µg L−1 and 1.20 µg L−1. The coprostanol/epicoprostanol ratio ranged from 1.32 (September) to 33.25 (February), suggesting that human sewage represents the key input of faecal material into the estuary. However, a correlation between the sterol profile of water above the oysters with that of water that enters from Tiptree Sewage Treatment Works (r = 0.82), and a sample from a site (Quinces Corner) observed to have a high population of Brent geese (r = 0.82), suggests that both sources contribute to the faecal pollution affecting the oysters. In identifying these key faecal inputs, sterol profiling has allowed targeted management practices to be employed to ensure that oyster quality is optimised.

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Puglisi, Edoardo, Marco Nicelli, Ettore Capri, Marco Trevisan, and Attilio A. M. Del Re. "Cholesterol, β-Sitosterol, Ergosterol, and Coprostanol in Agricultural Soils." Journal of Environment Quality 32, no. 2 (2003): 466. http://dx.doi.org/10.2134/jeq2003.0466.

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Puglisi, Edoardo, Marco Nicelli, Ettore Capri, Marco Trevisan, and Attilio A. M. Del Re. "Cholesterol, β-Sitosterol, Ergosterol, and Coprostanol in Agricultural Soils." Journal of Environmental Quality 32, no. 2 (March 2003): 466–71. http://dx.doi.org/10.2134/jeq2003.4660.

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Midtvedt, T., E. Lingaas, B. Carlstedt-Duke, T. HÖVerstad, A. C. Midtvedt, H. Saxerholt, M. Steinbakk, and K. E. Norin. "Intestinal microbial conversion of cholesterol to coprostanol in man." APMIS 98, no. 7-12 (July 1990): 839–44. http://dx.doi.org/10.1111/j.1699-0463.1990.tb05004.x.

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Blanch, Anicet R., Luis Belanche-Muñoz, Xavier Bonjoch, James Ebdon, Christophe Gantzer, Francisco Lucena, Jakob Ottoson, et al. "Tracking the origin of faecal pollution in surface water: an ongoing project within the European Union research programme." Journal of Water and Health 2, no. 4 (December 1, 2004): 249–60. http://dx.doi.org/10.2166/wh.2004.0022.

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The objectives of this study are to generate knowledge about methods to track the sources of faecal pollution in surface waters, with the aim of having one or a few easy procedures applicable to different geographic areas in Europe. For this, a first field study using already proposed methods (genotypes of F-specific RNA bacteriophages, bacteriophages infecting Bacteroides fragilis, phenotypes of faecal coliforms and enterococci, and sterols) has been done in five areas representing a wide array of conditions in Europe. The present faecal indicators (faecal coliforms, enterococci, sulfite reducing clostridia and somatic coliphages) have also been included in this first field study. At the same time some emerging methods have been settled or adapted to water samples and assayed in a limited number of samples. The results of this first field study indicate that no single parameter alone is able to discriminate the sources, human or non-human, of faecal pollution, but that a ‘basket’ of 4 or 5 parameters, which includes one of the present faecal indicators, will do so. In addition, numerical analysis of the data shows that this ‘basket’ will allow the successful building of predictive models. Both the statistical analyses and the studied predictive models indicate that genotype II of F-specific RNA bacteriophages, the coprostanol and the ratio coprostanol: coprostanol+epicoprostanol are, out of the studied parameters, those with a greater discriminating power. Either because unsuccessful adaptation of the methods to water samples or because the preliminary assays in water samples indicated low discriminating capability, only three (sorbitol-fermenting bifidobacteria, some species of bifidobacteria detected by PCR with specific primers and phages infecting Bacteroidestethaiotaomicron) of the newly assayed methods have been considered for a second field study, which is currently underway. Expectations are that these new tools will minimize the number of parameters in the ‘basket’, or at least minimize the difficulty in assaying them.

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Leeming, Rhys, Jonathan S. Stark, and James J. Smith. "Novel use of faecal sterols to assess human faecal contamination in Antarctica: a likelihood assessment matrix for environmental monitoring." Antarctic Science 27, no. 1 (June 25, 2014): 31–43. http://dx.doi.org/10.1017/s0954102014000273.

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AbstractWastewater containing human sewage is often discharged with little or no treatment into the Antarctic marine environment. Faecal sterols (primarily coprostanol) in sediments have been used for assessment of human sewage contamination in this environment, butin situproduction and indigenous faunal inputs can confound such determinations. Using gas chromatography with mass spectral detection profiles of both C27and C29sterols, potential sources of faecal sterols were examined in nearshore marine sediments, encompassing sites proximal and distal to the wastewater outfall at Davis Station. Faeces from indigenous seals and penguins were also examined. Faeces from several indigenous species contained significant quantities of coprostanol but not 24-ethylcoprostanol, which is present in human faeces.In situcoprostanol and 24-ethylcoprostanol production was identified by co-production of their respectiveepi-isomers at sites remote from the wastewater source and in high total organic matter sediments. A C29sterols-based polyphasic likelihood assessment matrix for human sewage contamination is presented, which distinguishes human from local fauna faecal inputs andin situproduction in the Antarctic environment. Sewage contamination was detected up to 1.5 km from Davis Station.

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Gagné, F., C. Blaise, B. Lachance, G. I. Sunahara, and H. Sabik. "Evidence of coprostanol estrogenicity to the freshwater mussel Elliptio complanata." Environmental Pollution 115, no. 1 (November 2001): 97–106. http://dx.doi.org/10.1016/s0269-7491(01)00089-6.

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Martins, César de Castro, Rosalinda Carmela Montone, Rosa Carvalho Gamba, and Vivian Helena Pellizari. "Sterols and fecal indicator microorganisms in sediments from Admiralty Bay, Antarctica." Brazilian Journal of Oceanography 53, no. 1-2 (June 2005): 1–12. http://dx.doi.org/10.1590/s1679-87592005000100001.

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Sediments from the proximity of Ferraz station outfall, located in Admiralty Bay, Antarctica, were analyzed for fecal indicator microorganisms and sterols during the austral summer of 1999/2000 in order to assess human sewage input. Concentrations of total sterols and coprostanol ranged from 0.09 to 19.6 ¼g.g-1 and < 0.01 and 14.0 ¼g.g-1 dry weight (dw), respectively. Our analyses indicated that only sites within to 400m of the sewage outfall exhibited a sterol signal characteristic of human sewage input. Low levels of coprostanol and high levels of cholesterol in distant sites could be attributed to natural sources such as marine mammals and planktonic organisms. Fecal indicator microorganisms (E. coli, fecal streptococci and Clostridium perfringens) were non-detectable beyond 50m from outfall. Both indicators (sterols and fecal indicator microorganisms) produced consistent data and fecal sterol parameters have sho wn themselves to be efficient in the evaluation of trace amounts of fecal material. This study concluded that sewage contamination is limited to the immediate vicinity of the sewage outfall. In general, the concentration of fecal sterols and microbiological indicators were lower than in other Antarctic areas.

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Gomes, Heyde Gonçalves, Silvia Keiko Kawakami, Satie Taniguchi, Pedro Walfir Souza Filho, and Rosalinda Carmela Montone. "Investigation of sewage contamination using steroid indexes in sediments of the Guajará Estuary (Amazon coast, Brazil)." Brazilian Journal of Oceanography 63, no. 4 (December 2015): 501–10. http://dx.doi.org/10.1590/s1679-87592015097506304.

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Abstract Amazonian aquatic systems are usually associated with pristine waters, however, irregular urban occupation of the hydrographic basins and sewerage deficiencies may lead to point and diffuse contamination. Sewage contamination in intertidal surface sediments from the Guajará Estuary, Brazilian Amazon coast, was evaluated using a set of steroids as biomarkers. Sediments collected along the urbanized margin were also analyzed for chlorophyll a, total organic carbon and grain sizes. Coprostanol, the main fecal sterol, was found at concentrations varying from 0.06 to 7.93 µg g-1 dry sediment, following the sequence Tucunduba > Ver-o-Peso > Porto da Palha > Tamandaré > Icoaraci > Miramar. Mixed sources of organic matter and coastal process probably concurred to produce weak correlations among the parameters. Plant derived sterols, including n-C30 alcohol and β-amyrinyl alkanoates, were clearly abundant, but they did not preclude the use of other steroid signals to the assessment of sewage contamination. High values of the steroid indexes involving 5α and 5β stanols and stanones highlighted sewage contamination at the sites with the lowest absolute coprostanol concentrations. The predominance of 5β stanols indicated a chronically sewage contamination of the area.

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Romanenko, Victor G., George H. Rothblat, and Irena Levitan. "Sensitivity of Volume-regulated Anion Current to Cholesterol Structural Analogues." Journal of General Physiology 123, no. 1 (December 29, 2003): 77–88. http://dx.doi.org/10.1085/jgp.200308882.

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Depletion of membrane cholesterol and substitution of endogenous cholesterol with its structural analogues was used to analyze the mechanism by which cholesterol regulates volume-regulated anion current (VRAC) in endothelial cells. Depletion of membrane cholesterol enhanced the development of VRAC activated in a swelling-independent way by dialyzing the cells either with GTPγS or with low ionic strength solution. Using MβCD–sterol complexes, 50–80% of endogenous cholesterol was substituted with a specific analogue, as verified by gas-liquid chromatography. The effects of cholesterol depletion were reversed by the substitution of endogenous cholesterol with its chiral analogue, epicholesterol, or with a plant sterol, β-sitosterol, two analogues that mimic the effect of cholesterol on the physical properties of the membrane bilayer. Alternatively, when cholesterol was substituted with coprostanol that has only minimal effect on the membrane physical properties it resulted in VRAC enhancement, similar to cholesterol depletion. In summary, our data show that these channels do not discriminate between the two chiral analogues of cholesterol, as well as between the two cholesterols and β-sitosterol, but discriminate between cholesterol and coprostanol. These observations suggest that endothelial VRAC is regulated by the physical properties of the membrane.

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Henning, Susanne, Jieping Yang, Shih Lung Woo, Ru-Po Li, Jianjun Huang, Gail Thames, Irene Gilbuena, et al. "California Strawberry Consumption Alters Gut Microbiome in Healthy Participants: A Pilot Study." Current Developments in Nutrition 4, Supplement_2 (May 29, 2020): 1561. http://dx.doi.org/10.1093/cdn/nzaa062_018.

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Abstract Objectives Based on the polyphenol and fiber content of strawberries (SB), it was our hypothesis that daily consumption of California strawberries will lead to changes in the composition of the intestinal microbiota, and concentration of fecal cholesterol and bile acid (BA) microbial metabolites. Methods We performed a randomized, double blind, parallel design intervention study. 28 healthy adults were randomized to either daily consumption of 26 g of SB powder (2 servings of fresh SB) or placebo (PL) powder for 4 wks. Stool samples were collected at baseline (BL), 4 and 6 wks (2 wks no SB/PL). Fecal microbiota was analyzed by 16S rDNA sequencing of the V4 region; fecal cholesterol, coprostanol, cholestanol, cholic acid (primary BA), chenodeoxycholic acid (primary BA), deoxycholic acid (2ndBA), lithocholic acid (2ndBA) by gas chromatography, serum cholesterol, triglyceride by colorimetric assay and serum pelargonidin glucuronide (PG) by high performance liquid chromatography. Results Serum PG, a SB anthocyanin, was found in all participants in the SB group. Two participants in the PL group showed serum PG and were excluded from the analyses. Daily SB increased the abundance of Christensenellaceae, Bifidobacteriaceae, Verrucomicrobiaceae and multiple members of the Lachnospiraceae, Ruminococcaceae family, and decreased significantly Alcaligenaceae/Sutterella comparing BL to wk4. Comparing the change from BL to wk4 between the SB and PL group, we found increased abundance of Alcaligenaceae/Sutterella and several members of the Clostridia class including Lachnopsiraceae and Ruminococcaceae and a decrease in Clostridiaceae. Comparing wk 4 to wk 6, we observed a reversal of Clostridiales/Christensenellaceae, Verrucomicrobiaceae, and Alcaligenaceae/Sutterella. No effects on alpha and beta diversity were observed. No significant difference in serum and fecal cholesterol, BA and bacterial metabolites was observed between SB and PL groups. Five participants did not form coprostanol. Comparing coprostanol producers to non-producers at baseline showed that most differences were observed in the Lachnospiraceae, Ruminococcaceae and Bacteroidaceae families. Conclusions SB consumption altered the gut microbiota, which was partially reversed after 2 wks of customary diet without SB. Funding Sources California Strawberry Commission.

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Nakakuni, Yamasaki, Yoshitake, Takehara, and Yamamoto. "Methyl Ether-Derivatized Sterols and Coprostanol Produced via Thermochemolysis Using Tetramethylammonium Hydroxide (TMAH)." Molecules 24, no. 22 (November 7, 2019): 4040. http://dx.doi.org/10.3390/molecules24224040.

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Sterols are widely distributed in nature from lipids in organisms to sediments. As a conventional method, extraction and derivatization with TMS have been applied for sterol analysis, requiring a long preparation time for gas chromatography–mass spectrometry analysis. In this study, for sterol analysis, thermochemolysis using tetramethylammonium hydroxide (TMAH) was applied. This method performs hydrolysis and methylation simultaneously; thus, free and ether-bonding sterols can be analyzed as sterol methyl ethers in a relatively short time period. A sediment sample from a tideland (the Yatsu tideland, Japan) was analyzed using the TMAH method, and we detected more than 10 sterols, which include cholest-5-en-3β-ol (cholesterol), 24-ethylcholest-5-en-3β-ol (sitosterol), 24-methylcholesta-5,22E-3β-ol (brassicasterol), 24-ethylcholesta-5,24(28)Z-dien-3β-ol (isofucosterol), 4α,23,24-trimethyl-5α(H)-cholest-22E-en-3β- ol (dinosterol), and 5β(H)-cholestan-3β-ol (coprostanol). The detection of the various sterols can be attributed to multiple natural and artificial sources around the Yatsu tideland. In this paper, the mass spectra of these sterols are provided together with an interpretation of their fragmentation patterns. Additionally, the fecal pollution in the Yatsu tideland is discussed in the context of the detection of coprostanol.

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Lye, H. S., G. Rusul, and M. T. Liong. "Removal of cholesterol by lactobacilli via incorporation and conversion to coprostanol." Journal of Dairy Science 93, no. 4 (April 2010): 1383–92. http://dx.doi.org/10.3168/jds.2009-2574.

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Leeming, R., and P. D. Nichols. "Concentrations of coprostanol that correspond to existing bacterial indicator guideline limits." Water Research 30, no. 12 (December 1996): 2997–3006. http://dx.doi.org/10.1016/s0043-1354(96)00212-6.

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Krahn, Margaret M., Catherine A. Wigren, Leslie K. Moore, and Donald W. Brown. "High-performance liquid chromatographic method for isolating coprostanol from sediment extracts." Journal of Chromatography A 481 (January 1989): 263–73. http://dx.doi.org/10.1016/s0021-9673(01)96770-6.

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Ren, Dewei, Ling Li, Alan W. Schwabacher, Jerry W. Young, and Donald C. Beitz. "Mechanism of cholesterol reduction to coprostanol by Eubacterium coprostanoligenes ATCC 51222." Steroids 61, no. 1 (January 1996): 33–40. http://dx.doi.org/10.1016/0039-128x(95)00173-n.

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41

Jeng, Woei-Lih, and Bor-Cheng Han. "Sedimentary coprostanol in Kaohsiung Harbour and the Tan-Shui Estuary, Taiwan." Marine Pollution Bulletin 28, no. 8 (August 1994): 494–99. http://dx.doi.org/10.1016/0025-326x(94)90523-1.

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42

Galeron, M. A., R. Amiraux, B. Charriere, O. Radakovitch, P. Raimbault, N. Garcia, V. Lagadec, F. Vaultier, and J. F. Rontani. "Seasonal survey of the composition and degradation state of particulate organic matter in the Rhône River using lipid tracers." Biogeosciences 12, no. 5 (March 5, 2015): 1431–46. http://dx.doi.org/10.5194/bg-12-1431-2015.

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Abstract. Lipid tracers including fatty acids, hydroxyacids, n-alkanols, sterols and triterpenoids were used to determine the origin and fate of suspended particulate organic matter (POM) collected in the Rhône River (France). This seasonal survey (April 2011 to May 2013) revealed a year-round strong terrestrial higher-plant contribution to the particulate organic matter (POM), with significant algal inputs observed in March and attributed to phytoplanktonic blooms likely dominated by diatoms. Major terrigenous contributors to our samples are gymnosperms, and more precisely their roots and stems, as evidenced by the presence of high proportions of ω-hydroxydocosanoic acid (a suberin biomarker). The high amounts of coprostanol detected clearly show that the Rhône River is significantly affected by sewage waters. Specific sterol degradation products were quantified and used to assess the part of biotic and abiotic degradation of POM within the river. Higher-plant-derived organic matter appears to be mainly affected by photo-oxidation and autoxidation (free radical oxidation), while organic matter of mammal or human origin, evidenced by the presence of coprostanol, is clearly more prone to bacterial degradation. Despite the involvement of an intense autoxidation-inducing homolytic cleavage of peroxy bonds, a significant proportion of hydroperoxides is still intact in higher plant debris. These compounds could affect the degradation of terrestrial material by inducing an intense autoxidation upon its arrival at sea.

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Green, Graham, and Peter D. Nichols. "Hydrocarbons and sterols in marine sediments and soils at Davis Station, Antarctica: a survey for human-derived contaminants." Antarctic Science 7, no. 2 (June 1995): 137–44. http://dx.doi.org/10.1017/s0954102095000198.

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A survey of hydrocarbons and sterols in marine and shoreline sediments was undertaken adjacent to Davis Station in Princess Elizabeth Land, Prydz Bay, Eastern Antarctica to determine the impact of a human settlement, including a sewage outfall on the local marine environment. Soil samples from selected locations onshore were also analysed to ascertain the extent of hydrocarbon contamination emanating from fuel storage facilities and other potential sources. The faecal sterol coprostanol was detected at 13.2 μg g−1 (60% of total sterols) in sediment adjacent to the Davis sewage outfall and up to 5.0 μg g−1 on the shoreline at Davis Beach. These concentrations indicate significant faecal contamination. The absence of coprostanol in faeces from the local wildlife confirms a human origin for this sewage biomarker. Hydrocarbons on the shoreline near Davis were present at up to 5.5 μg g−1 (dry weight of sediment). Biomarker profiles indicate an anthropogenic origin for these hydrocarbons. Onshore, degraded hydrocarbons derived from Special Antarctic Blend distillate were found at relatively high levels in soils at the fuel storage depot (up to 220 μg g−1). The source of these hydrocarbons appeared to be spillage from fuel storage tanks with possible contributions from fuel pipeline leakage and vehicle useage. Concentrations of polycyclic aromatic hydrocarbons in the soils were very low, generally below 1 ng g−1 (dry weight of sediment) for individual compounds.

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Galeron, M. A., R. Amiraux, B. Charriere, O. Radakovitch, P. Raimbault, N. Garcia, V. Lagadec, F. Vaultier, and J. F. Rontani. "Seasonal survey of the composition and degradation state of particulate organic matter in the Rhone River using lipid tracers." Biogeosciences Discussions 11, no. 10 (October 2, 2014): 14197–237. http://dx.doi.org/10.5194/bgd-11-14197-2014.

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Abstract. Lipid tracers including fatty acids, hydroxyacids, n-alkanols, sterols and triterpenoids were used to determine the origin and fate of suspended particulate organic matter (POM) collected in the Rhone River (France). This seasonal survey (April 2011 to May 2013) revealed a year-round strong terrigenous contribution to the plant-derived particulate organic matter (POM), with significant algal inputs observed in March and attributed to phytoplanktonic blooms likely dominated by diatoms. Major terrigenous contributors to our samples are gymnosperms, and more precisely their roots and stems, as evidenced by the presence of high proportions of ω-hydroxydocosanoic acid (a suberin biomarker). The high amounts of coprostanol detected clearly show that the Rhone River is significantly affected by sewage waters. Specific sterol degradation products were quantified and used to assess the part of biotic and abiotic degradation of POM within the river. Plant-derived organic matter appears to be mainly affected by photo-oxidation and autoxidation (free radical oxidation), while organic matter of human origin, evidenced by the presence of coprostanol, is clearly more prone to bacterial degradation. Despite the involvement of an intense autoxidation-inducing homolytic cleavage of peroxy bonds, a significant proportion of hydroperoxides is still intact in higher plant debris. These compounds could affect the degradation of terrestrial material by inducing an intense autoxidation upon its arrival at sea.

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LeBlanc, Lawrence A., James S. Latimer, John T. Ellis, and James G. Quinn. "The geochemistry of coprostanol in waters and surface sediments from Narragansett Bay." Estuarine, Coastal and Shelf Science 34, no. 5 (May 1992): 439–58. http://dx.doi.org/10.1016/s0272-7714(05)80116-7.

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46

Jeng, Woei-Lih, and Bor-Cheng Han. "Coprostanol in a Sediment Core from the Anoxic Tan-Shui Estuary, Taiwan." Estuarine, Coastal and Shelf Science 42, no. 6 (June 1996): 727–35. http://dx.doi.org/10.1006/ecss.1996.0046.

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47

Prange, I., A. Snog-Kjaer, G. Kofoed Nielsen, and H. Dam. "BACTERIAL CONVERSION OF CHOLESTEROL INTO COPROSTANOL INDEPENDENT OF CEREBROSIDES IN THE MEDIUM." Acta Pathologica Microbiologica Scandinavica 42, no. 1 (August 18, 2009): 29–32. http://dx.doi.org/10.1111/j.1699-0463.1958.tb01725.x.

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Haack, Sheridan K., Joseph W. Duris, Dana W. Kolpin, Lisa R. Fogarty, Heather E. Johnson, Kristen E. Gibson, Michael Focazio, Kellogg J. Schwab, Laura E. Hubbard, and William T. Foreman. "Genes Indicative of Zoonotic and Swine Pathogens Are Persistent in Stream Water and Sediment following a Swine Manure Spill." Applied and Environmental Microbiology 81, no. 10 (March 13, 2015): 3430–41. http://dx.doi.org/10.1128/aem.04195-14.

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ABSTRACTManure spills into streams are relatively frequent, but no studies have characterized stream contamination with zoonotic and veterinary pathogens, or fecal chemicals, following a spill. We tested stream water and sediment over 25 days and downstream for 7.6 km for the following: fecal indicator bacteria (FIB), the fecal indicator chemicals cholesterol and coprostanol, 20 genes for zoonotic and swine-specific bacterial pathogens by presence/absence PCR for viable cells, one swine-specificEscherichia colitoxin gene (STII gene) by quantitative PCR (qPCR), and nine human and animal viruses by qPCR or reverse transcription-qPCR. Twelve days postspill, and 4.2 km downstream, water concentrations of FIB, cholesterol, and coprostanol were 1 to 2 orders of magnitude greater than those detected before, or above, the spill, and genes indicating viable zoonotic or swine-infectiousEscherichia coliwere detected in water or sediment. STII gene levels increased from undetectable before or above the spill to 105copies/100 ml of water 12 days postspill. Thirteen of 14 water (8/9 sediment) samples had viable STII-carrying cells postspill. Eighteen days postspill, porcine adenovirus and teschovirus were detected 5.6 km downstream. FIB concentrations (per gram [wet weight]) in sediment were greater than in water, and sediment was a continuous reservoir of genes and chemicals postspill. Constituent concentrations were much lower, and detections less frequent, in a runoff event (200 days postspill) following manure application, although the swine-associated STII andstx2egenes were detected. Manure spills are an underappreciated pathway for livestock-derived contaminants to enter streams, with persistent environmental outcomes and the potential for human and veterinary health consequences.

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Reddy, Sheela, T. A. B. Sanders, R. W. Owen, and M. H. Thompson. "Faecal pH, bile acid and sterol concentrations in premenopausal Indian and white vegetarians compared with white omnivores." British Journal of Nutrition 79, no. 6 (June 1998): 495–500. http://dx.doi.org/10.1079/bjn19980087.

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Faecal bulk, pH, water content, the concentrations of neutral sterols and bile acids and dietary intakes were measured in twenty-two Indian vegetarian, twenty-two white omnivorous and eighteen white vegetarian premenopausal women. Faecal bulk and water content were greater and pH lower in the Indian vegetarians. Total faecal animal sterol and coprostanol concentrations expressed on a dry-weight basis were lower in the vegetarians compared with the omnivores. The faecal sterol concentrations were correlated with dietary cholesterol intake. Primary bile acids were detected in six Indian vegetarians, two white vegetarians and two white omnivores; secondary bile acids were detected in all the white omnivore and vegetarian subjects but not in two of the Indian vegetarians. Total faecal free bile acid and conjugated bile acid concentrations were lower in the white vegetarians compared with the omnivores. Faecal lithocholic acid concentrations were lower in both Indian and white vegetarians. The lithocholic: deoxycholic acid ratio and coprostanol: total animal sterols ratio were significantly lower in the Indian vegetarians compared with the omnivores. Both ratios were positively correlated with faecal pH. Stepwise multiple regression analyses were undertaken in order to identify which nutrients influenced faecal pH, lithocholic and deoxycholic acid concentrations. The intakes of starch and dietary fibre were negatively associated with faecal concentrations of lithocholic and deoxycholic acid. Starch intake alone was negatively associated with faecal pH. The results of this study confirm that diets high in dietary fibre decrease faecal bile acid concentrations and suggest that the complex carbohydrates present in Indian vegetarian diets influence faecal pH and inhibit the degradation of faecal steroids.

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Choi, Minkyu, Hyo-Bang Moon, Jun Yu, Sang-Soo Kim, Anthony S. Pait, and Hee-Gu Choi. "Nationwide monitoring of nonylphenolic compounds and coprostanol in sediments from Korean coastal waters." Marine Pollution Bulletin 58, no. 7 (July 2009): 1086–92. http://dx.doi.org/10.1016/j.marpolbul.2009.04.010.

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Journal articles on the topic 'Coprostanol'

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