Short-chain fatty acids properties

Milieu conditions in gastrointestinal tract can influence the pectin structure and properties. Under the acid conditions of the stomach (pH 2-4) extraction of pectin from plant cell walls and hydrolysis of side chains can occur. In small intestine (pH 5-6) -elimination of main chains or de-esterification seems to be possible. In caecum and colon (pH 6-8) a strong fermentation of pectin takes place causing depolymerization to oligomers and leading to formation of short chain fatty acids and gases. The presence of OligoGalA is not yet clarified. 

The short chain fatty acids include butyrate derivatives Hke phenylbu-tyrate, AN-9 (pivaloyloxymethyl butyrate) and valproate. Unfortimately, these compounds have poor potency and pharmacokinetic properties, including short half-life. Numerous Phase I studies with phenylbutyrate, in various oral and intravenous schedules [118-120] have been performed, with neurological toxicity at higher doses being reported. AN-9 showed initial promise in a Phase I study, where the MTD was not reached [121]. The subsequent Phase II study in nonsmall cell lung cancer in 47 patients resulted in fatigue, nausea and dysgeusia as common toxicities. Three partial responses (PR)... 

Although all the sodium salts are, as is indicated by the lowering of the surface tension, adsorbed at the interface the concentrations necessary to efiPect emulsification are so great for the salts of the short chain fatty acids that precipitation by the sodium ions results before the protective film can be built up. The first signs of emulsification are noted in the case of sodium caprate and sodium nonylate coinciding with the appearance of colloidal properties on solution. 

Introduction. The flavor of butter and butter fractions is very attractive to the human palate due to their content of very short chain fatty acids. Furthermore, the word butter is appreciated by the consumer. Due to this, there has been a growing interest in recent years, especially in Europe, to use butter stearin and other butter fractions in pastries such as Danish pastries and croissants (108, 109). The properties desired in puff pastry butter are similar to those outlined for puff pastry margarine in Section 5.2. 

LAB produce several compounds with antimicrobial properties as a result of nutrient competition with other microorganisms growing in the same niche. These antimicrobial active metabolites consist of nonspecific antimicrobial substances such as short-chain fatty acids (formic, acetic, propionic, butyric, and lactic acids), ethanol and hydrogen peroxide, and toxins including bacteri-ocins (nisin, reuterin, reutericyclin, pediocin, lacticin, enterocin, and others). 

The fermentation products of the bacteria include some lactic acid and some of the short-chain fatty acids such as butyric, acetobutyric, and propionic acids. Bacteria contain enzymes that split the bile salt, and as a result the detergent properties of bile are lost adding to malabsorption. 

Essential oils are volatile substances and chemically different from the fatty oils. Their characteristic compounds are monoterpenes and esters with short-chain fatty acids. There are about 2500 essential oils but only about 100 are used. The essential oils are used especially in the perfume industry and for cosmetic articles in the food industry for creating aromatic essences in plastics, artificial leather, rubber, floor wax, household sprays and in pharmaceutical preparations because of their pharmaceutical effects, their antiseptic properties, and to improve taste. 

A characteristic property of the crystalline silicic acids is their ability to intercalate polar organic molecules. Various types of guests are intercalated short-chain fatty acid amides, urea and derivatives, S- and V-oxides, amines, aromatic bases. 

Fats and oils are important food constituents. Their nutritional, chemical, and physical properties are influenced by the position of fatty adds, their chain length, and the degree of unsaturation. Usually, lipases are used to obtain modified fats with nutritionally improved properties and they provide high value fats such as cocoa butter that contains palmitic and stearic acids. Commercial lipases are mainly employed in the dairy industry for flavor enhancement in cheese (Mase et al., 2010 Omar et al., 1986), the acceleration of cheese ripening (Fox et al., 1996 Kheadr et al., 2002), the manufacture of cheeselike products, and the Upolysis of butterfat and cream (Purko et al., 1952 Seitz, 1974). Lipases release short-chain fatty acids that develop a tangy flavor and medium chain fatty acids that give a soapy taste to the end product (Sharma et al., 2011). 

Wamecke D, Schwartz AS and Hofer M (1982) Properties of the transport system for glucose in Propionibacterium freudenreichii ssp. shermanii. Zbl Bakt Hyg, Abt IC 3 547-548 Wawszkiewicz EL and Barker HA (1968) Erythritol metabolism by Propionibacterium pentosaceum. The overall reaction sequence. J Biol Chem 243 1948-1956 Webster GF and Cummins CS (1978) Use of bacteriophage typing to distinguish Propionibacterium acnes types I and II. J Clin Microbiol 7 84-90 Wegner WS, Reeves HC, Rabin R and Ajl SJ (1968) Alternative pathways of metabolism of short chain fatty acids. Bacteriol Rev 32 1-26... 

Plasticizers are generally required for the formation of protein-based materials (] 1,14-18). These agents modify the raw material formation conditions and the functional properties of these protein-based materials (i.e. a decrease in resistance, rigidity and barrier properties and an increase in flexibility and maximal elongation of the materials). Polyols (e.g. glycerol and sorbitol), amines (e.g. tri-ethanolamine) and organic acids (e.g. lactic acid) are the most common plasticizers for such applications. Completely or partially water insoluble amphipolar plasticizers such as short-chain fatty acids (e.g. octanoic acid) can be used since some protein chain domains are markedly apolar. 

Two main hypotheses have been advanced to explain the faecal bulking properties of fibre. The water-holding idea, mentioned above, is probably the most widely held view. In addition, it was suggested by Williams and Olmsted in 1936 that the way in which fibre increased faecal weight was through an effect of its metabolites, the short-chain fatty acids (acetic, propionic and butyric). They noted that dietary fibre was broken down in the gut and that the increased faecal weight was associated with an increased faecal excretion of short-chain fatty acids. 

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