Micro-organisms solubility

Generally speaking we consider that most micro-organisms live and grow in aqueous environments, and that the cytoplasm within cells in which enzymes function is also aqueous. On die other hand, most lipids are only sparingly soluble in aqueous media. Cholesterol, for example, has a solubility of less than 2 mg l 1 (equivalent to a concentration of less than 5 pmol l 1). Even at much lower concentrations (25-40 nmol l 1) it tends to aggregate into micelles. There is, therefore, a general problem of how to supply lipid substrates at sufficient concentration to produce reaction kinetics that are appropriate for industrial purposes. 

The use of organic solvent in the medium is one stategy that has been proposed for biocatalysis [9-15]. In the organic phase, the reactant has a much greater solubility than in the aqueous phase. This could significantly reduce the volume of the reaction mixture. Enzymes and micro-organisms have been shown to be active in the presence of organic solvents [16-20]. 

Micro-organisms inhabit the aqueous phase of an emulsion and thus it is necessary for the biocide not only to be water soluble but also to remain in the aqueous phase. 

These are true chemical solutions and are mixtures of soluble polyglycols (to give lubricity), corrosion inhibitors and water soluble extreme pressure additives. They are subject to attack by micro-organisms and as a consequence, they are often formulated with one or more preservatives. 

Azaguanosine 5 -mono-, di-, and triphosphates have been isolated from the soluble fractions of micro-organisms [98, 194-196] and of mouse tissues and neoplasms [101] and 8-azaguanylic acid was shown to be a substrate for the phosphokinases of hog kidney and beef liver [140]. 8-Azaguanosine mono-, di-, and triphosphates have also been synthesized chemically [138, 140b]. 

G. Metabolic Difference. Micro-organisms attack wood by secreting enzymes into the immediate structure which in turn break down the wood components into small, soluble units that become nutrients for the organism. The main destructive enzyme system the wood-rotters contain is a class of proteins known as cellulases. These enzymes break down he polymeric cellulose, the strong backbone of wood, into digestible units. Humans do not possess this enzyme system consequently, we cannot degrade cellulose-containing materials. 

B. H. Howard, Hydrolysis of the soluble pentosans of wheat flour and Rhodymenia palmata by ruminal micro-organisms, Biochem. J., 67 (1957) 643—651. 

Azauracil [1,2,4-triazine-3,5(2,4)-dione] inhibits the growth of various micro-organisms. When grown in the presence of 6-azauracil- -C, Streptococcus jaecalis accumulates radioactive metabolites in the acid-soluble fraction of the cells. A major metabolite is D-ribofuranosyl-6-aza-uracil. This material is identical with material prepared by condensing tri-O-benzoyl-D-ribofuranosyl chloride with the mercuric derivative of 6-azauracil, followed by debenzoylation. A second major metaboUte was tentatively shown to be D-ribosyl-6-azauracil 5-phosphate. Bacteria develop resistance against 6-azauracil and its D-ribosyl derivative. Resistant Streptococcus faecalis will not convert 6-azauracil to its D-ribosyl derivative or to other bound forms, and the bacterium has also lost the ability to incorporate uracil into the nucleic acids of its cells. 

Significant differences in the extent of distribution of drugs, particularly lipid-soluble organic bases, are usual between ruminant and monogastric species. After parenteral administration, lipophilic bases diffuse passively from the systemic circulation into ruminal fluid (pH 5.5-6.5), where they become trapped by ionization. These drugs are slowly reabsorbed or, if they possess fimctional groups suitable for metabolism by hydrolysis or reduction, they may be partially inactivated by ruminal micro-organisms. 

Are they safe to eat Micro-organisms which are pathogenic or toxic obviously can not be used as SCP sources. In addition most microbi ceUs have a higher content of nucleic add, particularly RNA, than conventional foods. When such cells are digested by arurnals these nudeic adds are metabolised to uric add. Unlike most other mammals, humans do not possess uricase, which oxidises uric add to soluble allantoid for... 

Dimethoate has low persistence in soil with a half-life of 20 days. It evaporates from dry soil surfaces and is biodegradable. Since dimethoate is broken down rapidly by soil micro organisms, its breakdown is much faster in moist soils. In alkaline soils, it is degraded by hydrolysis. Since it is highly soluble in water and adsorbs very poorly to soil particles, it may leach into groundwater. 

In the manufacture of fresh cheeses, e. g. quark, the pasteurised skim milk is inoculated with micro-organisms (Sc. lactis, Sc. cremoris). To accelerate the thickening, the enzym chymosin is added. After ripening - with a pH value of about 4.6 - the coagulated milk must be pumped through a separator, possibly including an ultrafiltration system, in order to separate the sour whey. The ultrafiltration would separate the whey into 2 phases the permeate (water soluble) and the retentate (protein phase). Finally the quark, retentate, cream, (fruit) preparations, flavourings or spices and herbs are added. 

---