title: In vitro inhibition of microbial methane production by 9,10-anthraquinone.
abstract: Monensin, 2,2-dichloroacetamide, and 9,10-anthraquinone were incubated for 24 h in ruminal fluid and buffer with 100:0, 50:50, and 10:90 forage-concentrate diets. Monensin (.5 ppm of the fluid) increased (P < .05) the molar proportion of propionate in the 50 and 100% forage diets but not in the high concentrate diet. At the same level of addition, 2,2-dichloroacetamide increased (P < .05) the molar proportion of propionate only in the 50:50 forage-concentrate diet. Relative to control cultures, monensin and 2,2-dichloroacetamide numerically decreased methane production in the 10 and 100% forage diets and decreased (P < .05) methane in the 50% forage diet. Hydrogen production was unaffected by treatment. Lack of an effect on fermentation end products in the high concentrate diet was probably a result of the low dose levels. In general, increasing levels of 9,10-anthraquinone (.5, 1.0, and 5.0 ppm) reduced total VFA concentration and the molar proportion of acetate, and increased propionate, butyrate and valerate. Increasing levels of 9,10-anthraquinone caused linear and quadratic decreases (P < .05) in methane production, and increases (P < .05) in hydrogen. There were no consistent effects on ammonia concentration in culture fluid from any of the compounds. In continuous culture of a 10:90 forage-concentrate diet, addition of 9,10-anthraquinone (10 ppm of the fluid/12 h) caused changes similar to those observed in batch culture with the exception of a decreased (P < .05) molar percentage of propionate, which may have been due to the high dose. The data are interpreted to indicate that 9,10-anthraquinone has the ability to alter in vitro microbial fermentation.
authors.affiliation: Delaware Agricultural Experiment Station, Department of Animal and Food Sciences, University of Delaware, Newark 19717-1303, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Garcia-Lopez
authors.forename: L
authors.initials: L
authors.lastname: Kung
authors.forename: J M
authors.initials: JM
authors.lastname: Odom
mesh_terms: D000081:Acetamides / Q000494:pharmacology; D000818:Animals; D000880:Anthraquinones / Q000032:analysis / Q000494:pharmacology*; D001421:Bacteria, Anaerobic / Q000302:isolation & purification / Q000378:metabolism*; D002417:Cattle; D004032:Diet / Q000662:veterinary; D005285:Fermentation; D006859:Hydrogen / Q000378:metabolism; D008297:Male; D008697:Methane / Q000378:metabolism*; D008985:Monensin / Q000378:metabolism; D012417:Rumen / Q000378:metabolism* / Q000382:microbiology*; D013997:Time Factors
chemical_list: D000081:Acetamides; D000880:Anthraquinones; C042834:9,10-anthraquinone; C013874:chloroacetamide; D006859:Hydrogen; D008985:Monensin; D008697:Methane