Glucose reaction mixture

Figure 1. Antioxidative effect and amount of material in retentates and dialysates after dialysis of histidine-glucose reaction mixture up to five times 12 h through dialysis tubing with a molecular weight cut-off of 1000 daltons.

Table II presents the quantitative results of those components volatile enough for GC analysis. At low pH the furan compounds predominate when both glucose and xylose are exposed to 300 C. This is not unexpected since all pentoses form 2-furaldehyde(2) in high yield when exposed to aqueous acid solution( ). However, the presence of 2 in the glucose reaction mixture is of interest. The major product obtained from hexoses at elevated temperatures and aqueous acid is 5-hydroxymethyl-2-furaldehyde(1) with minor amounts of 2-(hydroxyacetyl)furan(15). The 2-furaldehyde has been detected after acidic treatment of fructose(1 ), glucose(15,17), and is a major component after the thermolysis of cellulose in distilled water( ). One plausible explanation for the formation of 2 may involve loss of formaldehyde(18) from glucose with consequent pentose formation. It should be noted that the pyrolysis of 1 does produce a small amount of 2( ). However, the reaction conditions are sufficiently different to suggest a different mechanism for hydrothermolysis.

Table 1. Antioxidant activity of peptide-glucose reaction mixture and soybean paste in vitro...

PG peptide (casein hydrolyzate)-glucose reaction mixture. 

SCAVENGING ACTIVITY OF AMINO ACID, PEPTIDE-GLUCOSE REACTION MIXTURES AGAINST ROS... 

With ammonia, aminoacetylfuran is very easily converted to 2-(2-furoyl)-5-(2-furyl)-l Himida-zole, known as FFI, which was previously isolated from acid hydrolysates from protein/glucose reaction mixtures ... 

Slight impurities in the d-glucose are apt strongly to color the reaction mixture but do not materially affect the yield. 

Cell lysates from mutant strains of X. campestris were incubated with radiolabelled UDP[14C] glucose or GDP[,4C] mannose, the other sugar nudeotide substrates being unlabelled. The reaction mixture was then divided into lipid and soluble fractions. Where would you expect the radiolabel to be found and what produd, if any, would you expert from strains with defidendes in the following genes ... 

An excess of PGD is added to the reaction mixture containing glucose 6-phosphate and NADP to assure that 2 moles of NADPH are produced per mole of glucose-6-phosphate oxidized (109). This method has been improved by Nicholson et. al (110) to make... 

Human CYPs are multicomponent enzyme systems, requiring at a minimum the CYP enzyme component and a reductase component to be functional. The reductase requires a reduced nicotinamide cofactor, typically NADPH, and this cofactor must be regenerated to provide a steady supply of reducing equivalents for the reductase. Regeneration is accomplished with a separate substrate and enzyme. Glucose-6-phosphate and glucose-6-phosphate dehydrogenase have been widely used for this purpose. The overall complexity of the reaction mixtures and their cost have been barriers to the widespread use of recombinant human CYPs for metabolite synthesis in the past. 

The amylase of Aspergillus oryzae causes a very rapid decrease in the viscosity of its substrates and a very rapid disappearance from its reaction mixtures of products which give color with iodine. When examined under favorable conditions71 at 40° with Lintner s soluble potato starch, the achroic point was reached with highly purified maltase-free amylase when approximately 12% of the glucose linkages of the substrate had been ruptured. 

Table X 4 summarizes similar data for the hydrolysis by maltase-free malt alpha amylase of beta dextrins obtained from arrowroot starch by the action of beta amylase. The beta dextrins were precipitated with alcohol from the reaction mixture of arrowroot starch after it had reached a limit in the hydrolysis at 60% theoretical maltose. The beta dextrins were hydrolyzed extensively by malt alpha amylase. Glucose was liberated in very small amounts even in the later stages of the hydrolysis of these beta dextrins maltose was liberated in appreciable amounts and, at equivalent hydrolyses, appeared to be formed somewhat more rapidly from the beta dextrins (Table X) than from the untreated starch (Table IX). Upon hydrolysis with malt alpha amylase the molecular weights of the beta dextrins dropped appreciably but not as extensively as when arrowroot starch was hydrolyzed directly by malt alpha amylase.

Both maltose and glucose were present in the reaction mixtures with amylose,85 (Table XI). Therefore, glucose is liberated in addition to maltose from this straight-chain substrate as well as from unfractionated starch by maltase-free malted barley alpha amylase (Table IX). 4 It appears from the results reported by Myrback (Table XI) 5 that amylose can be hydrolyzed completely to fermentable sugar by malted barley alpha amylase but only after a prolonged period of hydrolysis (32 days). A more recent report by Myrb ck87 confirms and extends this con-(87) K. Myrbftck, Arch. Biochem., 14, S3 (1947). 

The first direct approach requires a long stand of the reaction mixture under high temperature. In the crystal form the product could be receive only after the fermentative splitting of un-reacted glucose. In the further studies [4-6] the direct method was somewhere improved and applied to other mono- and disaccharides, however, there were no principal changes in the synthesis methods. 

X 10 2 M Tris HC1 buffer, pH 7.5, 2.4 X 10 3 M glucose 6-phosphate (G-6-P), 1.6 units glucose 6-phosphate dehydrogenase (G-6-P dH), 5.1 X 10"5 M NADP, and 2.7 X 10 3 M KC1. In addition, the following chemicals were included in the final concentration indicated 5.1 X 10-3 M NADH, 1% (W/V) bovine serum albumin (BSA), and 1.0 mg aldrin in 0.1 ml ethanol. Whole body homogenate experiments included all of the above chemicals unless otherwise noted. Reaction mixtures were incubated with swirling in test tubes at 30 - 1°C. Reactions in Steps 1-4 of the experimental sequence were stopped after 1 hr and Steps 6-8 after 15 min, by the addition of 2 ml 5% TCA. 

A sodium vanillate stock solution (50 mg mL ) was prepared by dissolving equimolar amounts of vanillic acid and NaHCOs in 0.1 m Na2HP04 (pH 7). Reaction mixtures of 50 mL contained 0.4 % glucose, 1.5 g of wet E. coli cells, 200 mg of sodium vanillate in pH 7, 0.1 M Na2HP04. 

The cell pellet of E. coli JM109 pGro7 pJOE4072.6 was resuspended in phosphate buffer to a final OD at 600 nm of around 20. To 100 mL of this suspension in a 1 L shake flask racemic 3-phenylbutan-2-one (0.15 g, 1 mmol), /3-cyclodextrin (0.07 g, 0.5 mmol) and 1 m glucose solution (2 mL) were added. The reaction mixture was incubated at 30 °C and 220 rpm. After 4 h, further 1 m glucose solution (2 mL) was added. 

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