Biomaterial Database

[Rumen bacterial metabolism as affected by extracellular redox potential]. 1994

H I Kalachniuk, and M Marounek, and L H Kalachniuk, and O H Savka

The redox potential (Eh) in the digestive tract of ruminants varies mostly within the ranges from -300 to +200 mV, in the rumen medium: from -130 to -200 mV. Eh and pH changes are of a linear character. Enhanced fermentation moves Eh towards negative values and improves growth of microorganisms. Eh values become even more negative as affected by Na2S, NaOH, cysteine and NaHSO3. Addition of picrate, sodium nitrate, hydrochloric acid, copper sulphate, gaseous oxygen and particularly heavy metals (silver and mercury) promotes positive Eh values and inhibits metabolism. Optimum Eh values for Megasphaera elsdenii are more negative, than those for Streptococcus bovis. In the process of S. bovis growth, the production of lactate, VFA, CH2O2 and NH3 increases, Eh and pH values decrease. More positive Eh values inhibit metabolism and growth rates of Selenomonas ruminantium, Bacteroides amylophilus, Bacteroides succinogenes and Streptococcus bovis to different degrees.

UI	MeSH Term	Description	Entries
D010084	Oxidation-Reduction	A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).	Redox,Oxidation Reduction
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D005285	Fermentation	Anaerobic degradation of GLUCOSE or other organic nutrients to gain energy in the form of ATP. End products vary depending on organisms, substrates, and enzymatic pathways. Common fermentation products include ETHANOL and LACTIC ACID.	Fermentations
D006041	Goats	Any of numerous agile, hollow-horned RUMINANTS of the genus Capra, in the family Bovidae, closely related to the SHEEP.	Capra,Capras,Goat
D006090	Gram-Negative Bacteria	Bacteria which lose crystal violet stain but are stained pink when treated by Gram's method.	Gram Negative Bacteria
D006094	Gram-Positive Bacteria	Bacteria which retain the crystal violet stain when treated by Gram's method.	Gram Positive Bacteria
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012417	Rumen	The first stomach of ruminants. It lies on the left side of the body, occupying the whole of the left side of the abdomen and even stretching across the median plane of the body to the right side. It is capacious, divided into an upper and a lower sac, each of which has a blind sac at its posterior extremity. The rumen is lined by mucous membrane containing no digestive glands, but mucus-secreting glands are present in large numbers. Coarse, partially chewed food is stored and churned in the rumen until the animal finds circumstances convenient for rumination. When this occurs, little balls of food are regurgitated through the esophagus into the mouth, and are subjected to a second more thorough mastication, swallowed, and passed on into other parts of the compound stomach. (From Black's Veterinary Dictionary, 17th ed)	Rumens
D012756	Sheep	Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.	Ovis,Sheep, Dall,Dall Sheep,Ovis dalli