Com starch, hydrolysed

Hydrolyzed corn starch CAS 8029-43-4 EINECS/ELINCS 232-436-4 Synonyms Com starch hydrolysate Com sugar symp Starch, com, hydrolysate Symps, com Definition Hydrolysate of corn starch derived by acid, enzyme, or other method of hydrolysis Uses Binder, vise, control agent, humectant in cosmetics, emulsions Trade Name Synonyms Nutrex PV [Fabriquimica]... 

Raw materials for the fermentation of ethanol are sugar molasses (Brazil), com steep liquor and corn starch hydrolysate (USA). Industrial ethanol fermentation is highly developed and the stoichiometric yield can be as high as 1.9 mol mol-1 [25, 26]. The... 

It has been accounted that, on a production scale of PHB of 100,000 tons per year, the production costs will decrease from US 4.91 to US 3.72 kg , if hydrolysed com starch (US 0.22 kg ) is chosen as the carbon source instead of glucose (US 0.5 kg ) [33]. But this is still far beyond the cost for conventional polymers, which in 1995 was less than US 1 [32]. Lee et al. estimated that PHB and mcI-PHA can be produced at a cost of approximately US 2 kg [36]. The precondition therefore would be attaining high productivity and the use of inexpensive carbon sources. Among such substrates, molasses [37], starch [38], whey from the dairy industry [37-42], surplus glycerol from biodiesel production [39, 43], xylose [44, 45], and plant oils [46] are available. 

The strain Alcaligenes lotus DSM 1124 is able to grow and to accumulate PHAs on many different carbon sources. In order to lower the production costs it is important to find alternative, cheap carbon sources. Bogensberger showed that the strain is able to use green syrup and molasses. Further possible raw materials are starch hydrolysates, glycerol, and whey as carbon sotux s, and com steep liquor as nitrogen source. 

Nutrapon TLS-500. See TEA-lauryl sulfate Nutrapon W1367 Nutrapon WAC 3005 Nutrapon WAQ, Nutrapon WAQE 2364. See Sodium lauryl sulfate NutraSweet . See Aspartame Nutrex PG. See Glycosaminoglycans Nutrex PV. See Hydrolyzed com starch Nutrex RT. See Spleen extract Nutrex TM. See Thymus hydrolysate Nutricoi Konjac. See Konjac flour Nutrifos 088 Nutrifos BC Nutrifos Powd.. See Pentasodium triphosphate Nutrifos SK. See Trisodium dipotassium tri polyphosphate... 

The advantage of starch as a carbon source is that its price is lower than that of glucose. Choi and Lee (1999) estimated that on a production scale of 100,000 tons of PHB per year, production costs would decrease from US 4.91 to 3.72 kg if hydrolysed com starch (US 0.22 kg" ) were used instead of glucose (US 0.49 kg ). Most processes for PHA production based on starch require the conversion of starch to easily convertible substrates such as glucose by enzymatic or chemical hydrolysis (Chen et al. 2006 Huang et al. 2006). Alternatively, VFAs can be produced as fermentation substrates by acidogenesis (Yu et al. 2002). The production of P(3HB-co-3HV) by H. mediterranei on extruded starch in a pH-stat fed-batch mode was recently described by Chen et al. (2006). Here, an exogenous source of a-amylases was used. 

Dextrins obtained on y-irradiation of starch have been found to contain appreciable proportions of unidentified carbonyl residues. The properties of starch for starch-gel electrophoresis were improved by y-irradiation. The decreases in viscosity and iodine-absorption values, as well as the increased reducing properties, indicated that amylose and amylopectin are degraded by y-irradiation in the same way as native starches. Although each of the amylose and amylopectin components of amylomaize starch in y-irradiated and untreated samples was hydrolysed by a-amylase to the same extent, y-irradiated amylose had a low p-amylolysis limit. /-Irradiated amylomaize and com starches were hydrolysed to greater extents by a-amylase as the radiation dose was increased, and differences were detected in the products of enzymic degradation of amylomaize and corn starches following y-radiolysis. The water-soluble dextrins formed on y-irradiation of maize starch have been examined. ... 

Succinic acid Carbon substrate Com starch wastes and wood hydrolysate MetaboHc engineering production 2.5-3.19 g/L/h Chemical intermediates BioAmber, DSM/ Roquette Kimetal. (2004), Zheng etal.(2010), Jager and Biichs (2012)... 

The subsequent advance was rather fortuitous and rested more with serendipity than with scientific logic. A search was made for cheaper more effective replacements for casein hydrolysate. Amongst the tested materials was com steep liquor (CSL). CSL is a by-product of the manufacture of starch from maize kemals. Whole maize is incubated in warm water, at 50°C acidified with SO2. Thermophilic bacteria hydrolyse proteins and other components of the kemals, thereby loosening the starch granules. These are removed, leaving behind the steep liquor which is used to treat further maize kemals. Ultimately, the liquor is too viscous to re-use and the liquor is concentrated and used as cattle feed. It was this material that was used for penicillin fermentation. Surprisingly, the yield of penicillin increased by a further 5-10 fold giving yields of 50-100 ig ml. 

The data given in Table V show not only that pancreatic amylase hydrolyzes unfractionated starch and a linear substrate at different rates but also that, for equivalent time intervals with the same concentration of pancreatic amylase, the relative concentrations of the products formed from these two substrates differ. In addition, Table VIM,M summarizes comparative data for the products of the hydrolyses of potato starch, of com amylose, and of waxy maize starch when equivalent numbers of glucosidic linkages of these substrates had been broken. 

Commercial dextrins are specifically the oligomers of starch. White dextrins, so called because of their visual appearance, are produced from a 30-40% suspension under the mildest possible hydrolysis conditions (79-120°C for 3-8 h in 0.2-2% H2S04 or HC1). Yellow dextrins and British gums are the partial hydrolysates at higher time-temperature integrals. Maltodextrins, dextrose equivalent20 5-19, derive from controlled enzyme or acid partial hydrolysis of gelatinized corn starch. The 20-24 dextrose equivalent hydrolysates tire com syrups (Appi, 1991). 

However, for economy of production, maximum yields of alkaloids, and ease of recovery of the products, certain culture media containing relatively simple nutrient sources are preferred. For example, the media which are useful in the production of the alkaloids include an assimilable source of carbon such as glucose, sucrose, starch, molasses, dex-trins, corn steep solids, corn syrup liquor, sorbitol, mannitol, lactose, and the like. A preferred source of carbon is mannitol. Additionally, the media employed contain a source of assimilable nitrogen such as oatmeal meat extracts, peptones, amino acids and their mixtures, proteins and their hydrolysates, com steep liquor, soybean meal, peanut meal and ammonium salts of organic acids such as the citrate, acetate, malate, oxalate, succinate, tartrate and like salts. 

Some methods available offer the use of am-yloglucosidase alone. Work done with com and potato starches illustrated that even vmder ideal conditions amyloglucosidase does not fully convert starch to dextrose, although the shortfall is small. The limit dextrin was more noticeable in corn starch hydrolysis. Proof was obtained by studying the reaction kinetics, and analyzing the hydrolysates by ion chromatography using pulsed amperometric detection. There remained always a small amount of a limit dextrin, and in the case of potato starch some other low molecular mass residues. 

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