Pyruvate sodium

The optimal feeding profile based on the model is shown in Figure 3 and the simulation profiles are shown in Figure 4 for initial substrate concentrations of 90 mM benzaldehyde and 108 mM sodium pyruvate, and initial PDC activity of 4.0 U ml carboligase. Feeding was programmed at hourly intervals and the initial reaction volume would increase by 50% by the end of the simulated biotransformation. 

Simulation profile of fed batch PAC biotransformation kinetics at 6°C with initial PDC activity of 4.0 U carboligase ml, 90 mM benzaldehyde and 108 mM sodium pyruvate. Feeding was performed hourly as illustrated in Fig. 3 and the initial reaction volume of 30 ml (which would be used experimentally) increased to 45 ml at the end of reaction. 

In media selective for enterobacteria a surface-active agent is the main selector, whereas in staphylococcal medium sodium and lithium chlorides are the selectors staphylococci are tolerant of salt concentrations to around 7.5%. Mannitol salt, Baird-Parker (BP) and Vogel-Johnson (VJ) media are three examples of selective staphyloccocal media. Beside salt concentration the other principles are the use of a selective carbon source, mannitol or sodium pyruvate together with a buffer plus acid-base indicator for visualizing metabolic activity and, by inference, growth. BP medium also contains egg yolk the lecithin (phospholipid) in this is hydrolysed by staphylococcal (esterase) activity so that organisms are surrounded by a cleared zone in the otherwise opaque medium. The United States Pharmacopeia (1990) includes a test for staphylococci in pharmaceutical products, whereas the British Pharmacopoeia (1993) does not. 

Chorionic gonadotropin. Follicle stimulating hormone Urea, Uric add. Bilirubin, Cortisol, n-Maimitol. n-Glucose, Sodium pyruvate, 4-hydroxy-3-methoxy mandelic add, 4-Nitro-phenol, 17 Amino adds in HQ, Angiotensin-I, Tripahnitin, Bone meal (8 elements), Bone ash (8 elements), lithium carbonate Luteinizing hormone. Thyroid stimulating hormone... 

Activated sludge Reactive Yellow-107, Reactive Black-5, Reactive Red-198, Direct Blue-71, glucose, sodium pyruvate Klebsiella sp. strain VN-31 [39]... 

The ability of cyanide to combine with carbonyl groups of some intermediary metabolites (e.g., sodium pyruvate, a-ketoglutarate) to form cyanohydrin has been used for antidotal purposes. Pretreatment of mice with 1 g/kg sodium pyruvate intraperitoneally prior to subcutaneous injection of potassium cyanide caused an increase in the LD50 values from 3.1 to 5 mg CN /kg (Schwartz et al. 1979). Sodium pyruvate also prevented the development of convulsions in cyanide-exposed mice. Similarly, intraperitoneal pretreatment of mice with 2 g/kg a-ketoglutarate before the intraperitoneal injection of potassium cyanide increased the LD50 value from 2.68 to 13.32 mg CN /kg (Moore et al. 1986). It was further demonstrated that both sodium pyruvate and a-ketoglutarate enhanced the antidotal effects of other cyanide antagonists (e.g., sodium thiosulfate, sodium nitrite) (Moore et al. 1986 Schwartz et al. 1979). 

Schwartz C, Morgan RL, Way LM, et al. 1979. Antagonism of cyanide intoxication with sodium pyruvate. Toxicol Appl Pharmacol 50 437-441. 

Flitsch and Turner reported the generation of a sialic acid DCL using an aldolase enzyme [36,37], The DCL design is shown in Scheme 2.7, and is based on the cleavage of sialic acid (58a) to A-acetylmaimosamine (56a) and sodium pyruvate (57), catalyzed by an aldolase enzyme. 

Scheme 2.7 Aldol reaction of ManNAc analogues and sodium pyruvate to produce sialic acid, catalyzed by A-acetylneuraminic acid (NANA) aldolase.

Appropriate culture medium for the specific tumor cell line(s) under test (e.g., Dulbecco s Modified Eagle Medium (DMEM) lx liquid GlutaMAX I, 4,500 mg/L o-glucose, sodium pyruvate DMEM/F12 (1 1) lx liquid with GlutaMAX I). 

To evaluate the presence of possible interferences, the following metabolites were tested at their physiological concentration bilirubin, sucrose, cholesterol, triglycerides, acetone, urea, uric acid, citric acid, L-ascorbic acid, citrate, pyruvate, haemoglobin, y-globulin, sodium pyruvate, NaCl, KC1, Ca2+ and EDTA. Urea, uric acid, L-ascorbic acid, NaCl, KC1 and Ca2+ generated a slight interference. 

Eupergit 250L (Rohm Chemie, 400 mg) was added to a solution of sialic acid aldolase (8 mg, 64 U) in 1 M potassium phosphate buffer pH 7.4 (3.2 mL) containing 0.04 M sodium pyruvate and 0.02% NaN3 the suspension was stirred for 3 days at room temperature under N2. The gel was washed with 0.1 M potassium phosphate buffer pH 7 (10 mL) and stored at 4°C in this buffer in the presence of 0.04 M pyruvate and 10 3 M dithiothreitol. A unit yield of 40% was usually obtained for immobilization. 

In early experiments it was found that sodium pyruvate was required for fixation of N2 in cell-free extracts, and that large amounts of C02 and H2 accumulated. Investigation showed that cleavage of pyruvate supplies cells with two important products ... 

Immobilized sialyl aldolase (50 mL of gel, 68 U) was added to a mixture of 88% pure A-acetylmannosamine (20 mmol), sodium pyruvate (180 mmol), 1,4-dithiothreitol (0.2 mmol), and sodium azide (20 mg) in 0.05 M potassium phosphate buffer, pH 7 (150 mL). The suspension was gently stirred under nitrogen for 4 d at 37°, the reaction being monitored by t.l.c. in 7 3 propanol - water. The gel was removed by filtration, washed with the buffer, and A-acetylneuraminic acid (2) was isolated by chromatography on Dowex 1 X8 (HCOj-) resin, using a gradient of formic acid as the eluant, in 66% yield. The gel was used in four successive runs. Starting from 17 g of 88% pure A-acetylmannosamine, the procedure allowed the synthesis of 14 g of A-acetylneuraminic acid (2). In the end, the recovered gel retained 80% of its enzymic activity. 

Method. 0.2 ml of an ethanolic solution of hydrochloric acid (0.65 ml of concentrated hydrochloric acid per litre of absolute ethanol) is added to the dry keto steroid in a small test-tube [103,104]. 0.2 ml of a solution of DNS-hydrazine (2 mg/ml in absolute ethanol) is then added. The contents of the test-tube are heated in a bath in boiling water for 10 min for hydrazone formation. The tube is cooled and 0.2 ml of sodium pyruvate (5 mg/ ml in absolute ethanol) is added to destroy the excess of DNS-hydrazine. The tube is permitted to stand at room temperature for 15 min. 6 ml of diethyl ether and 3 ml of Q.5-N aqueous sodium hydroxide are then added and the tube is shaken. The diethyl ether layer is removed and evaporated to dryness. The residue is dissolved in a small volume of chloroform (0.2-0.5 ml) for TLC analysis. The keto steroid derivatives are separated on layers of Alumina G (Woelm) (thickness, 250 fim) which have been activated at 120 °C for 30 min. The solvent consists of dioxane-chloroform (1 9). The separated derivatives are observed under UV light at 366 nm. The limits of detection are in the 1-2 nmole range for each steroid. 

Fig. 4. Study of the equilibrium between pyruvic acid and glycine. 5.6 x 10 4 M Sodium pyruvate, 0.005% gelatin, glycine buffer pH 9.2. Concentration of the form of glycine with the free amino group is given in the polarogram. Ionic strength kept constant by addition of sodium chloride. Curves starting at —0.8 V, S.C. E., 200 mV/absc.,

Media basal RPMI 1640 medium requires supplementation with sodium pyruvate, L-glutamine, and penicillin/streptomycin before use. The supplements are supplied as concentrates of 50X or 100X, and the appropriate amounts should be added. Standard tissue culture media for hybridoma production contain 5%, 10%, or 15% fetal bovine serum (FBS see Note 6). Sufficient quantities should be prepared in advance and a sterility check should be performed on them prior to use. 

Typical experimental procedures are as follows The test drug candidate is incubated with pooled human liver microsomes (e.g., 1 mg protein/mL) that were previously preincubated with ABT (1 or 2 mM) for 30 minutes at (37 1)°C in the presence of an NADPH-generating system. Incubations of the drug candidate in the absence of ABT serve as controls. For hepatocytes, suspensions of freshly isolated or cryopreserved hepatocytes (lx 106 cells/ mL) are preincubated with 100-pM ABT for 30 minutes in 0.25 mL of Krebs-Henseleit buffer or Waymouth s medium (without phenol red) supplemented with FBS (4.5%), insulin (5.6 pg/mL), glutamine (3.6 mM), sodium pyruvate (4.5 mM), and dexamethasone (0.9 pM) at the final concentrations indicated. After the preincubation, the drug candidate is added to the incubation and the rate of metabolism of the drug candidate is compared in hepatocytes or microsomes with and without ABT treatment. A marked difference in metabolism caused by ABT is evidence that CYP plays a prominent role in the metabolism of the drug candidate. 

In considering the application of enzyme catalysis to DCC, we were encouraged by the thermodynamic resolution of a dynamic mixture of aldol products by Whitesides and co-workers through the use of a broad-specificity aldolase to lead to reversible formation of carbon-carbon bonds under mild conditions.35 For the current investigation36 we chose a related enzyme, N-acetylneuraminic acid aldolase (NANA aldolase, EC 4.1.3.3), which catalyzes the cleavage of N-acetylneuraminic acid (sialic acid, 27a) to A-acetylmannosamine (ManNAc, 28a), and sodium pyruvate 29 in the presence of excess sodium pyruvate, aldol products 27a-c are generated from... 

Generation of the dynamic library proved straightforward a mixture containing equimolar amounts of the three substrates 28a-c and two equivalents of sodium pyruvate was incubated in the presence of NANA aldolase (Figures 29.2 and 29.3). Aliquots of the incubation mixture were withdrawn at intervals and analyzed by ion-exchange HPLC. 

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