Of cysteine hydrochloride

The occurrence of 1 and 3 in a flavor model system has been pointed out by G.J. Hartmann et al. (j 2.. LL). Moreover, 2-methyl-3-furanthiol 1 and bis-(2-methy1-3-fury 1)-disulfide 3. have already been identified as major constituents in a model meat system that was prepared by refluxing an aqueous solution of cysteine hydrochloride, thiamin hydrochloride, and hydrolyzed vegetable protein (12,13) for four hours. 

Phosphate-Cysteine-EDTA Buffer Solution Dissolve 7.1 g of anhydrous dibasic sodium phosphate in about 800 mL of water, and then dissolve in this solution 14.0 g of disodium EDTA dihydrate and 6.1 g of cysteine hydrochloride monohydrate. 

Zueva and Protopopov studied the anion effect on the redox reaction of KI03/H202/Cys HC1 in H2S04 (1982-1), and observed increases in amplitude of oscillations. Also, the effect of cysteine hydrochloride on the alterations of oscillations in the same system were studied, (1982-2). 

Several e.s.r. studies have been made on single crystals of cysteine hydrochloride monohydrate. On irradiation with 1 5 MeV electrons at 77 K Akasaka observed an isotropic doublet as the main radical species with a high anisotropic but axial symmetric g factor, and attributed this to the SCHjCH(CX)OH)NHjCl radical, as found by Kurita and Gordy for cystine . Remarkable broadening was observed on warming and at... 

The reaction of cysteine hydrochloride H-Cys(H)-OH HCl with 2 equiv Scm-Cl in methanol (1 h) provides the HCl salt of Scm-protected cysteine, H-Cys(Scm)-OH HCl. The presence of excess HCl effectively prevents the nucleophilic attack by the amine function of cysteine to Scm-Cl cystine is a by-product if less Scm-Cl is used. The intermediate reacts with excess alkyl thiols and 1 equiv triethylamine in methanol or methanol-chloroform to afford S-alkylsulfenylcysteines, H-Cys(SR)-OH.i ... 

Tajiri, T., Matsumoto, K. and Hara, K. (1976). Storage stability of freeze-dried carrots. III. The content of carotene as affected by the addition of cysteine hydrochloride at various temperatures. J. Japan. Soc. Hort. Sci.. 45, 81-88. 

Cysteine acetate solution 1%. Dissolve l.Og of cysteine hydrochloride monohydrate, 0.775g of sodium acetate trihydrate, and 12.5g of anhydrous sodium sulphate in water and make up to 100ml. 

The preparation of linear monothioacetals or dithioacetals may be accomplished by either the reaction of cysteine hydrochloride with the appropriate a-halo ether or sulphide in methanol or better by the base catalyzed alkylation of cysteine in liquid ammonia. Young and associates [11, 115] have utilized alkylation reactions of this type to prepare several... 

Dissolve 4 g of light white soluble casein by shaking with 90 ml of water. Adjust the pH to 7 0, using bromothymol blue as external indicator, and make up the volume to 100 ml. Dissolve 0-5 g of cysteine hydrochloride in 10 ml of water and adjust the pH to 7 0. Triturate 0-5 g of papain with the solution of cysteine hydrochloride and make up to 100 ml. 

The dried papaya latex (180 g.), 100 g. of Celite, and 150 g. of washed sand are mixed in a mortar and ground thoroughly with 200 to 300 ml. of 0.04 M cysteine (6.3 g. of cysteine hydrochloride is dissolved in 100 ml. of 0.054 N NaOH this contains an excess of alkali in order to bring the aqueous extract to pH 5.7). The suspension is allowed to settle and the supernatant solution is decanted. The extraction and grinding are repeated with another 300 ml, portion of the cysteine solution this is decanted as before and the mortar is washed with the cysteine solution until a total volume of 1 liter has been used for extraction and washing. The resulting suspension is stirred well and filtered on a large Biichner... 

To a suspension of 35.2 grams (0.2 mol) of L-cysteine hydrochloride monohydrate stirred in a reaction vessel containing 87 ml of 91% aqueous tetrahydrofuran under a nitrogen... 

The balloon was removed briefly while aliquots were taken. The flask was flushed again with nitrogen and the balloon was then replaced. Thin-layer chromatographic analyses were carried out on glass plates coated with silica gel G which were purchased from Analtech, Newark, Delaware. With a 10 2 3 (v/v/v) solution of 1-butanol, acetic acid, and water as developing solvent, the Rf values for the product and L-cysteine hydrochloride are 0.19 and 0.25, respectively. 

Walsh et al. (2000) have reported the reduction of L-cystine hydrochloride to L-cysteine hydrochloride and have covered laboratory kinetics to process modelling for several m cells. 

The selection of an appropriate antioxidant depends on factors such as stability, toxicity, efficiency, odor, taste, compatibility with other ingredients, and distribution phenomena between the two phases. Antioxidants that give protection primarily in the aqueous phase include sodium metabisulfite, ascorbic acid, thioglycerol, and cysteine hydrochloride. Oil-soluble antioxidants include lecithin, propyl gal-late, ascorbyl palmitate, and butylated hydroxytoluene. Vitamin E has also been used, but its virtue as a natural antioxidant has been the subject of some controversy. 

L-Cysteine hydrochloride E920 All flour used in the manufacture of biscuits, except wholemeal or flour to which E220 sulfur dioxide or E223 sodium metabisullite has been added 300... 

L-Cysteine is normally added as L-cysteine hydrochloride or L-cysteine hydrochloride monohydrate. When the ADD process was in use it was incorporated in a compound improver. If L-cysteine is used as a pastry relaxant it is supplied mixed with either soy flour or an inactivated wheat flour. This of course aids dispersion and the measurement of very small quantities. 

The flour improver would contain sufficient L-cysteine hydrochloride to give 35 mg kg-1 of flour (equivalent to around 27 mg kg-1 of L-cysteine) with sufficient potassium bromate to give 25 mg kg-1 of flour and sufficient ascorbic acid to give 50 mg kg-1 of flour. The above assumes a flour of 12% protein that has had added to it up to 20 mg kg-1 potassium bromate. Alternatively, with an untreated flour all the potassium bromate would be in the improver. 

Various additives are used to act as dough relaxants. They are L-cysteine hydrochloride, sulfur dioxide, possibly in the form of sodium metabisulfite, and acids such as acetic acid in vinegar. 

Table 10. Comparison of filterpress reactor sizes for the electrosynthesis of L-cysteine hydrochloride. Catholyte = 2 M HC1 at 25°C j = 2 kAm 2 v = 0.35 ms 1 Pb cathode in presence of turbulence promotor DEM cell [13, p. 327J...

Figure 10. VCD and absorption spectra in the CH stretching region of (a) L-cysteine 0.83 M in DjO, path length 200 nM, and (b) L-cysteine hydrochloride, 0.8 M in D2O, path length 200 iiM. (Reproduced with permission from ref. 89. Copyright 1985 American Chemical Society.)...

Acetylcysteine Acetylcysteine, A-acetyl-L-cysteine (23.2.4), is synthesized by reacting L-cysteine hydrochloride with acetic anhydride in the presence of sodium acetate [11-13],... 

Various crystalline states of cysteine, cysteine hydrochloride, and cysteine hydrochloride hydrate have been tested for solid-state reactivity. Thus, (R)-352 and (i )-352-HCl-H20 were also reactive in the solid-state. This was verified by quantitative solid-solid reactions with paraformaldehyde (354) in stoichiometric ball-milling experiments at room temperature giving 100% yield of R)-355 [12] or (J )-355-HCl [10] after drying. 

Fading of acetone extracts of pure NO-myoglobin solutions could be prevented by adding 1 ml of fresh 0.5% neutralized cysteine hydrochloride to 9 ml of NO-myoglobin solution. 

Note. (1) This amino ester is prepared as the corresponding hydrochloride by heating (R)-cysteine hydrochloride in methanol saturated with hydrogen chloride, followed by evaporation (cf. Expt 8.7). The hydrochloride is partitioned between dichloro-methane and sodium hydrogen carbonate solution evaporation of the organic layer affords the pure amino ester which is used immediately. 

To a suspension of 35.2 grams (0.2 mol) of L-cysteine hydrochloride monohydrate stirred in a reaction vessel containing 87 ml of 91% aqueous tetrahydrofuran under a nitrogen atmosphere there is added 54.4 grams (0.4 mol) of sodium acetate trihydrate. The mixture is stirred for 20 minutes at room temperature to insure neutralization of the hydrochloride salt resulting in the formation of a suspension of equimolar amounts of cysteine and sodium acetate. 

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