Microbial acidic

Combined use of lactate fermentation and ED separation has been proposed to overcome the main drawbacks of this fermentation process, that is, low microbial acidic productivity and expensive downstream processing of lactic acid fermentation broths (Boyaval et al., 1987 Hongo et al., 1986 ... 

Morihara, K., and Oka, T. (1973). Comparative specificity of microbial acid proteinases for synthetic peptides. 3. Relationship with their tiypsinogen activating ability. Arch. Biochem. Biophys., 157, 561-572. 

Hydrolysis was performed at pH 2.8 with a microbial acid protease (Molsin). Each degree of hydrolysis was measured with 10 % trichloroacetic acid (TCA) and represented as (TCA-soluble N / total N) x 100. 

Heavy metal mobilization is often followed by microorganism and plant uptake, and intracellular accumulation. Filamentous fungi transport heavy metals and radionuclides along their hyphae. This may be a mechanism of mobilization from mycor-rhizal fungi to higher plants. An alternative pathway involves direct root uptake of heavy metals mobilized by microbial acid production or chelation. 

The map was therefore reinterpreted for the revised positions of the molecular boundary near the helical segment. The molecular boundaries were also slightly changed in two other places where the separation of molecules was also not well defined on the map. After this modification, the entrance into the cavity became wider and the two-domain structure of the enzyme more prominent. The dimensions and the shape of the molecule became very similar to those of microbial acid protease (14). 

K. Morihara, T. Oka, K. Oda and S. Murao, Shionogi Col, and University of Osaka Prefecture, "Specificity of Microbial Acid Proteinases on Synthetic Substrates, Relationship to Their Behavior Against Pepstatin". 

Oklahoma City, Purification of Microbial Acid Proteases by Pepstatin-Sepharose Affinity Chromatography . 

Microbial leaching of metals from ores is a promising adjunct to more aggressive metal recovery technologies (77), but is generally achieved by oxidative processes that generate very acidic waters. It seems unlikely that similar approaches will be of much value in removing contaminant metals and metalloids from soils. 

Lactic acid-producing bacteria associated with fermented dairy products have been found to produce antibiotic-like compounds caUed bacteriocins. Concentrations of these natural antibiotics can be added to refrigerated foods in the form of an extract of the fermentation process to help prevent microbial spoilage. Other natural antibiotics are produced by Penicillium wqueforti the mold associated with Roquefort and blue cheese, and by Propionibacterium sp., which produce propionic acid and are associated with Swiss-type cheeses (3). 

Aliphatic-Garboxylics. There are only two herbicides present in this class, trichloroacetate [76-03-9] (TCA) and dalapon [75-99-0]. These are used primarily for the selective control of annual and perennial grass weeds in cropland and noncropland (2,299). Dalapon is also used as a selective aquatic herbicide (427). Dalapon and TCA are acidic in nature and are not strongly sorbed by sods. They are reported to be rapidly degraded in both sod and water by microbial processes (2,427). However, the breakdown of TCA occurs very slowly when incubated at 14—15°C in acidic sods (428). Timing not only accelerates this degradation but also increases the numbers of TCA-degrading bacteria. An HA has been issued for dalapon, but not TCA (269). 

Lactic acid [50-21-5] (2-hydroxypropanoic acid), CH CHOHCOOH, is the most widely occurring hydroxycarboxylic acid and thus is the principal topic of this article. It was first discovered ia 1780 by the Swedish chemist Scheele. Lactic acid is a naturally occurring organic acid that can be produced by fermentation or chemical synthesis. It is present ia many foods both naturally or as a product of in situ microbial fermentation, as ia sauerkraut, yogurt, buttermilk, sourdough breads, and many other fermented foods. Lactic acid is also a principal metaboHc iatermediate ia most living organisms, from anaerobic prokaryotes to humans. 

Another microbial polysaccharide-based emulsifier is Hposan, produced by the yeast Candida lipolytica when grown on hydrocarbons (223). Liposan is apparentiy induced by certain water-immiscible hydrocarbons. It is composed of approximately 83% polysaccharide and 17% protein (224). The polysaccharide portion consists of D-glucose, D-galactose, 2-amino-2-deoxy-D-galactose, and D-galacturonic acid. The presence of fatty acyl groups has not been demonstrated the protein portion may confer some hydrophobic properties on the complex. 

Experimental procedures have been described in which the desired reactions have been carried out either by whole microbial cells or by enzymes (1—3). These involve carbohydrates (qv) (4,5) steroids (qv), sterols, and bile acids (6—11) nonsteroid cycHc compounds (12) ahcycHc and alkane hydroxylations (13—16) alkaloids (7,17,18) various pharmaceuticals (qv) (19—21), including antibiotics (19—24) and miscellaneous natural products (25—27). Reviews of the microbial oxidation of aUphatic and aromatic hydrocarbons (qv) (28), monoterpenes (29,30), pesticides (qv) (31,32), lignin (qv) (33,34), flavors and fragrances (35), and other organic molecules (8,12,36,37) have been pubflshed (see Enzyp applications, industrial Enzyt s in organic synthesis Elavors AND spices). 

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