Showing papers on "Citric acid published in 1974"

Control of keratinization with alpha-hydroxy acids and related compounds. I. Topical treatment of ichthyotic disorders.

Abstract: Topical preparations containing α-hydroxy acids and closely related compounds were found to exert profound effects on epidermal keratinization in ichthyosis. Therapeutically efficacious compounds include citric acid, ethyl pyruvate, glycolic acid, glucuronic acid, 3-hydroxybutyric acid, 2-hydroxyisobutyric acid, lactic acid, malic acid, methyl pyruvate, pyruvic acid, tartaric acid, and tartronic acid. These materials appear to influence the process of keratinization per se, but do not seem to be keratolytic.

Composition and Stability of Iron and Copper Citrate Complexes in Aqueous Solution

Abstract: The acidity constants of citric acid and the stability constants of the citrate complexes of copper(II), iron(II), and iron(III) have been measured at 25 °C in 0.1 M KNO3 background. The measuremen...

Process for the production of a formed high moisture pet food product

Abstract: A process for the production of a pet food product resembling a "cooked" hamburger patty is set forth, which has a moisture content exceeding about 40% by weight and is stabilized against bacterial and mycotic penetration comprising: grinding raw animal meat into particles of a substantially uniform size, heating the same and impregnating the meat with a preservative composition which comprises a mixture of a bacteriostatic agent and an edible antimycotic. A critically defined range of expanded protein pieces are added to the final product which is between about 25 to 90% by volume of the product. The addition of a critically defined percentage of the expanded protein pieces provides a realistic chunky appearance and gives the product a shear value which exceeds about .080 ft. lb./gram. The bacteriostatic agent is preferably an organic acid selected from the group consisting of succinic acid, pyruvic acid, fumaric acid, adipic acid, glucono-Δ-lactone, tartaric acid, lactic acid, citric acid, malic acid and mixtures thereof or an acid salt such as sodium hexametaphosphate and calcium acetate. The edible antimycotic is preferably a mixture of sorbic acid and salts thereof.

Process of producing alkali metal or ammonium citrates

Abstract: Alkali metal or ammonium citrates are produced from solutions of citric acid obtained by chemical reaction or by fermentation by extraction by means of a specific water-immiscible mixture of aliphatic amines and organic solvents and re-extracting the resulting organic solvent mixture with an aqueous solution of an alkali metal hydroxide, carbonate or bicarbonate, ammonia, or their salts.

Method for cleaning and passivating a metal surface

Abstract: A cleaning solvent useful in the cleaning of metal surfaces, e.g. nickle-iron alloys, contains sulfamic acid, citric acid, a solvent for hydrocarbon residues, and a surfactant. Metal surfaces are cleaned by contacting the surface with the cleaning solvent and then passivated by contact with aqueous solutions of citric acid or sodium nitrite or a combination of the two.

Nonenzymatic Browning In Synthetic Systems Containing Ascorbic Acid, Amino Acids, Organic Acids, And Inorganic Salts

Abstract: The browning reactions between ascorbic acid and the 20 amino acids except tyrosine were studied at 44° and 72°C in model systems and the colour formation was followed by measurement of the absorbance at 400 nm. The progress and the extent of the colour development in unbuffered systems were dependent on temperature, incubation period, individual amino acids, and other additives. All amino acids except cysteine interacted with ascorbic acid, resulting in more pronounced colour formation than when ascorbic acid was present alone. Cysteine protected ascorbic acid against the formation of the brown pigment. Tryptophan exceeded all the other amino acids in enhancing the browning of ascorbic acid. At 72°C colour development caused by ascoibic acid and tryptophan was further enhanced by the presence of malic acid, citric acid, Feso4, Cuso4, and Na2Hpo4, but colour formation was reduced by fumaric acid, tartaric acid, succinic acid, Cacl2, Nahso3, tetrasodium pyrophosphate, sodium tripolyphosphate, sodium tetraphosphate, sodium metaphosphate, and sodium polyphosphate.

Colorimetric determination of piperazine in pharmaceutical formulations

Abstract: Piperazine can be satisfactorily determined in pharmaceutical preparations or formulations such as effervescent granules and elixirs containing hexamine, colchicine, atropine sulphate, sodium benzoate, lithium benzoate, lithium citrate, sodium citrate, sodium hydrogen carbonate, tartaric acid, citric acid, lactose, sucrose and Tinct. ammi visnaga. The diluted sample solution is treated with a 0·6 per cent. aqueous 1,2-naphthoquinone-4-sulphonate solution in the presence of acetate-citrate buffer at pH 7·5. The temperature of the reaction should be between 10 and 15 °C and the colour produced is measured at 490 nm.

Schnelle Bestimmung von Citrat in Wasch‐ und Reinigungsmitteln durch Titration mit Cu‐Lösung

Abstract: Die Komplexbildung von Cu(II)-Ionen mit Citronensaure in schwach alkalischer Losung gestattet deren direkte Titration bei visueller Endpunktbestimmung mit Metallindikatoren. Es wird eine Vorschrift zur Bestimmung von Citronensaure und ihren Salzen in Wasch- und Reinigungsmitteln mitgeteilt. Rapid Determination of Citrate in Washing and Cleansing Agents by Titration with Cu-Solution Complex formation of Cu(II)-ions with citric acid in weak alkaline solution permits direct titration of the acid using metal indicators for the visual determination of end point. A procedure for the determination of citric acid and its salts in washing and cleansing agents is reported.

Aluminum hydrates and salts of carboxylic acids

Abstract: Aluminum salts of a carboxylic acid selected from the group consisting of ascorbic acid, acetic acid, and citric acid are formed by contacting the carboxylic acid with activated aluminum. The activated aluminum is formed by combining highly pure aluminum with another metal which has an affinity for hydrogen in the presence of a proton source. Typically, the other metal can be gallium and the proton source can be hydrochloric acid. Included in the aluminum salts which can be formed are polymeric aluminum salts.

Effect of Sodium on the Transport and Utilization of Citric Acid by Aerobacter (Enterobacter) aerogenes

Abstract: Sodium inhibited citrate uptake by two of the four strains of Aerobacter (Enterobacter) aerogenes used in these studies, had no effect on one strain, and stimulated citrate uptake by one strain. Two of the four strains grew well anaerobically on citrate in the presence of Na+, one grew poorly, and one grew not at all either in the presence or absence of Na+. Na+ stimulated the aerobic growth of one strain on citrate, increased the total growth but not the rate of growth of one strain, and prolonged the lag phase but not the rate of growth or total growth of two strains. The experimental data reported herein, therefore, indicate that there are appreciable physiological differences among strains of A. aerogenes.

Metabolism in Penicillium isariiforme on Exposure to Light, with Special Reference to Citric Acid Synthesis

Abstract: SUMMARY: When exposed to light, cultures of Penicillium isariiforme showed a sharp decrease in citric acid accumulation in the medium compared with parallel cultures in continuous darkness, and a rise in the production of other low molecular weight intracellular intermediates, lipids, nucleic acids and protein. The significance of these phenomena is discussed.

Nontoxic general purpose liquid cleaning compositions

Abstract: This invention relates to liquid cleaning compositions and more particularly, to compositions that have a low pH, i.e., about 9.5 or below, and which consist essentially of, on a weight basis, about 3-10% surfactant, 1-3% isopropyl alcohol, 1-3% citric acid, 0.5 to 1.6% sodium tetraborate, 0.02 to 1.2% anhydrous sodium hydroxide, 0 to 1.0% anhydrous ammonium hydroxide and 84 to 95% water.

Verwitterungsversuche mit organischen Säuren an einigen schwerlöslichen Fe-Pb-Zn und Cu Erzmineralen, angewendet auf die Genese des Kupferschiefers

Abstract: The 1–2 mm fraction of FeS2, Fe3O4, PbS, PbSO4, ZnS, ZnCO3, Cu2S and Cu2(OH)2CO3 was dissolved in water, dilute HCl and 0.01 m organic acids (tannin, salicylic acid and citric acid) at 1 atm and 20° C. Duplicate samples of one gram each were placed in 50 ml of solvent with shaking once each day for one month at pH's of 2, 4 and 6. The pH of all the solutions was maintained by periodic addition of either HCl or NaOH. Comparing the results at pH 6, a value observed under surface conditions, the organic acids had a higher metal ion concentration because of their complexing ability. Results at pH 6 in ppm of the metal ions are shown below: For example the Fe concentration dissolved from pyrite in water was 0.02 ppm but 2.3–4.3 in the organic acids. From malachite 0.2 ppm Cu were dissolved by water but 25–1550 ppm by the organic acids. In general Cu minerals seem to be more soluble in organic acids than the Pb, Zn and Fe minerals. The different solution power of the organic acids within the experiments seems not to be caused by the crystallography of the minerals tested. Further there apparently is no preferential complexing of an organic acid with respect to a distinct anion or cation of the minerals. The experiments therefore show, that it is difficult to predict exactly which organic acid is most effective in dissolving minerals. However the experiments should apply to natural weathering conditions of ore minerals and may aid in understanding metal ion transport. For example the origin of the high Cu concentration in the sedimentary “Kupferschiefer” are more easily explained by weathering and transport of Cu in the form of organo-metallic complexes than by reaction with only water. The Cu content in organic acids is much higher than in water and the Cu concentration in the solutions now is not so strongly controlled by the solubility of Cu-cabonates and phosphates.

Color of processed sweet potatoes: effect of additives

Abstract: The additives, ethylenediaminetetraacetic acid (EDTA), stannous chloride, citric acid, ascorbic acid and sodium bisulphite were added to syrup and vacuum packs of sweet potatoes. Addition of EDTA, SnCl2, citric acid and sodium bisulphite was effective in decreasing darkening of the processed product. SnCl2, EDTA and citric acid were also effective in preventing discoloration after exposure of the product to air. The action of the additives is attributed to a disruption of the reaction leading from oxidation of polyphenols to the production of dark-colored compounds.

Enzymatic Studies on the Conversion of Citric Acid Fermentation to Polyol Fermentation in Hydrocarbon-assimilating Yeast Candida zeylanoides

Abstract: Production of polyols such as erythritol, d-mannitol and d-arabitol by citric acid-producing yeasts occurred only when the medium-pH was controlled at acidic pH, as described in the previous papers.In order to elucidate the conversion mechanism of citric acid fermentation to polyol fermentation, the effect of pH on the activities of enzymes involved in polyol synthesis and tricarboxylic acid cycle was studied. Shifting down of the medium-pH from 5.5 to 3.5 led immediately to the change of intracellular pH, from 6.5~6.7 to 5.5~5.7. Such the change affected remarkably on the activities of intracellular enzymes. Citrate synthase was significantly depressed at pH 5.7, but isocitrate lyase and phosphoenolpyruvate carboxykinase were reversely stimulated at this pH.In some yeast strains incapable of polyol production, the change of medium-pH reflected directly on intracellular pH, whereby almost all enzymes were inhibited.From these results, the conversion of citric acid production to polyol production was expla...

Process for the production of citric acid

Abstract: Citric acid is selectively produced by fermentation of a mutant yeast strain which requires the presence of iron in the culture medium. Citric acid is accumulated in the culture medium and isolated therefrom.

Dye bleach preparation for the photographic silver dye bleach process

Abstract: The invention relates to a dye bleach preparation which contains in addition to an acid, a water-soluble iodide and optionally a dye bleach catalyst at least one bifunctional sulphur compound having a sufficient solubility in the preparation and a low vapor pressure and containing at least one HS-group and at least one oxygen, nitrogen, phosphorus or additional sulphur atom, the sulphur atom of each HS-group being separated from the next oxygen, sulphur, nitrogen and phosphorus atom present in the molecule by at least three carbon atoms. The subject of the present invention is a dye bleach preparation for the photographic silver dye bleach process, which contains an acid, a water-soluble iodide and optionally a dye bleach catalyst. The preparation is characterised in that it contains at least one organic, at least bifunctional sulphur compound of which the solubility is at least 5×10- 4 mol per liter of preparation and of which the vapour pressure in the temperature range of -20°C to +100° C is at most as great as that of water, and which contains at least one HS-- group and at least one oxygen, nitrogen, phosphorus or additional sulphur atom, with the sulphur atom of each HS-- group being separated from the next oxygen, sulphur, nitrogen and phosphorus atom present in the molecule by at least three carbon atoms. The HS-- group can also be separated from the next oxygen, nitrogen, phosphorus or sulphur atom by a ring system, where in every case the shortest link between the two hetero-atoms must comprise at least three carbon atoms. Preferred sulphur compounds correspond to the formulae (1) to (16) which follow: ##EQU1## In these formulae, the symbols in every case have the same meaning, and in particular denote the following: A. an aliphatic, araliphatic or heterocyclic bridge member. A1. an aliphatic bridge member, an aralkylene radical, an aralkylidene radical or a benzene radical which is bonded, on non-adjacent carbon atoms, to the H-S- and B1 -groups. B. one of the groups of the formulae ##EQU2## wherein M denotes a cation, X denotes an anion, R1 and R2 denote a hydrogen atom, a lower alkyl group, a lower hydroxyalkyl group or the radical of a benzenesulphonic acid and R3 denotes a lower alkyl group and R1 and R2 located on the same nitrogen atom can also form a heterocyclic ring with the latter. B1. one of the groups ##EQU3## --SO3 M, --COOH (for R1 and R2, see above). B2. one of the groups --COOH, --SO3 cation, ##EQU4## --N(CH3)2, --N(C2 H5)2 (for R1 and R2, see above). B3. one of the groups --COOH, --SO3 cation and ##EQU5## (for R1 and R2, see above). B4. a carboxylic acid amide group (which can optionally carry one or two substituents on the nitrogen atom) or a sulphonic acid group (optionally in the form of a salt). M1. one of the cations H, Na, K, NH4, ##EQU6## m, n, p, q, r, s and t denote integers, as follows: 1 ≦ m ≦ 4 1 ≦ n ≦ 21 ≦ p ≦ 22 ≦ q ≦ 122 ≦ r ≦ 61 ≦ s ≦ 41 ≦ t ≦ 23 ≦ s + t The following compounds may be mentioned as examples: 3-Mercapto-propionic acid, 3-mercapto-propionic acid amide, 3-mercapto-propionic acid N-(4'-sulpho-phenyl)amide, 3-mercapto-propionic acid N-(3'-sulpho-phenyl)amide, 3-mercapto-propionic acid N,N-di-(β -hydroxyethyl)-amide, the guanidinium salt of 3-mercapto-propanesulphonic acid, 3-mercapto-1-dimethylaminopropane, 3-mercapto-butyric acid, 4-mercapto-butyric acid, 4-mercapto-butyric acid amide, 4-mercapto-butyric acid N-(4'-sulpho-phenyl)-amide, 4-mercapto-butyric acid N-(β-hydroxyethyl)-amide, 4-mercapto-butyric acid N-(6'-sulpho-naphthyl)-amide, 1-mercapto-butane-4-sulphonic acid, 1-mercapto-n-pentane-5-sulphonic acid, 1-mercapto-hexane-6-sulphonic acid, 10-mercapto-decane-1-sulphonic acid, 4-mercapto-1-diethylaminobutane hydrobromide, 4-mercapto-butane-phosphonic acid, 4-mercapto-butanol-(1), 4-mercapto-butyric acid N-(4'-sulphamoyl-phenyl)-amide, 6-mercapto-caproic acid, 5-mercapto-caproic acid, 3-mercapto-valeric acid, 4-mercapto-valeric acid, 5-mercapto-valeric acid, 3-mercapto-2-(mercaptomethyl)-propionic acid, 2-(mercaptomethyl)-succinic acid, 4-mercapto-butyronitrile, 1,3-dimercapto-2-methylpropane, 5-mercaptopentanephosphonic acid, 3-mercaptopropanephosphonic acid monoethyl ester, 3-mercapto-hexane-1,6-dicarboxylic acid, 4-mercaptobutyric acid β-methoxyethyl ester, 4-mercaptobutyric acid β-hydroxyethyl ester, α-methylmercaptotoluene-4-sulphonic acid, 3- or 4-amino-thio-phenol, 3-mercaptophenyl-N,N,N-trimethylammonium iodide, 4-mercapto-pyridine, 4-mercaptobenzenesulphonic acid, 4-N,N-dimethylamino-1-mercaptobenzene, 5-methyl-4-mercapto-caproic acid, 4,5-dimethyl-4-mercapto-caproic acid and 4,5-dimethyl-5-mercapto-caproic acid. The sulphur compounds to be used according to the invention can also be added to the dye bleach preparation in the form of their salts, especially of the alkali metal salts, or of inorganic or organic ammonium salts. In general it suffices to use 1 to 10 mol per cent of the sulphur compound, relative to the amount of iodide present, and if appropriate solvents, such as dimethylformamide, tetrahydrofurane or benzyl alcohol can also be added to the dye bleach preparation. Examples of suitable acids for the dye bleach baths are sodium bisulphate, sulphamic acid, acetic acid, citric acid, organic sulphonic acid, hydrochloric acid, sulphuric acid or phosphoric acid. The water-soluble iodide can be, for example, potassium iodide, sodium iodide, ammonium iodide or hydriodic acid. The dye bleach catalyst can either be dissolved in the dye bleach preparation or be contained in the photographic material to be bleached and can be, for example, a pyrazine, a quinoxaline or a phenazine. The sulphur compounds can be solid or liquid at room temperature and, as mentioned, their vapour pressure within the temperature range of -20°C to +100°C may only be at most equal to the vapour pressure of water. Alternatively to being in the form of a bath, the dye bleach preparation can, for example, also be a gel-like thickened composition, in the form of a colloidal mass or photographic layer. By using suitable technical measures such as, for example, providing protective layers or encapsulating the active components, the dye bleach preparations can be introduced into a photographic material in such a way that the dye-bleaching action can only come into operation on processing the photographic material. In special cases, mixtures of the iodide and of the sulphur compounds can also be present as such, whilst the acid and dye bleach catalyst are accommodated in another phase (compare, for example, French Pat. Specification 1,504.238). When using the dye bleach preparation according to the invention for bleaching reducible image substances, such as azo dyestuffs, nitro dyestuffs and diazonium salts, in the presence of metallic images, these metallic images can, in a known manner, be the converse of the original (negative) or in the same sense as the original (positive). It is desirable, after developing and before the dye-bleaching, to dissolve out of the material all metal salts, such as silver chloride or silver bromide, which may still be present (that is to say to fix the material), since otherwise the iodide content of the dye bleach bath would rapidly be exhausted and major amounts of sparingly soluble silver iodide would form at the same time. After the dye-bleaching, the silver which remains is removed in a known manner. In addition to the constitutents mentioned, the dye bleach baths can contain customary additives such as complex-forming agents, wetting agents and solvents. The dye bleach baths according to the present invention remain stable for a long period, do not undergo any discolouration, give results of good reproductibility even in continuously operating machines and in addition exhibit very advantageous behaviour with regard to corrosion of the containers and parts of the apparatus with which they come into contact. The sulphur compounds of the indicated composition which are present in the baths do not increase the corrosiveness and in some cases even reduces it. The particularly favourable behaviour of these sulphur compounds with regard to corrosion, even in comparison with such mercapto compounds as, for example, 1-mercapto-2,3-propanediol or 2-mercaptosuccinic acid, which do not have the composition circumscribed at the beginning of this text, can be demonstrated by various methods, for example also by electrochemical and therefore time-saving methods. In the examples which follow, percentages denote percentages by weight.

Fat-liquoring agent for waterproofing leather and skins

Abstract: A process for preparing waterproof leathers by fat-liquoring with an aqueous liquor containing esters of citric acid with higher fatty alcohols which are used as the impregnating agent, characterized in that the fat-liquoring agent contains a mixture emulsified in water which consists of (A) an acid ester of citric acid with a higher fatty alcohol having chain lengths of 12 to 22 carbon atoms and (B) an organic alcohol solvent for the citric acid ester which is totally or partially soluble in water and which have a boiling point above 100°C.

Studies on the Chemical Compositions of Citrus junos in Korea

Abstract: The chemical components of Citrus junos produced in Korea were divided into two parts; common and special components respectively. In the former the relation between the physiological effects of the plant and its ripening process was observed periodically while the latter was analyzed the ripening fruits for their effective utilization as food. The results are summarized as follows: 1. The analytical result of seasonal change showed that the rind ratio was higher than the flesh ratio and on a regional basis, the rind ratio was higher in the islands than on land areas. 2. In the experiment the moisture was increased until the third period, but afterwards it was made constant. While the content of crude fat, cellulose, ash, total acid and soluble non-nitrogen material were decreased until the third period and the cotent of cellulose and total acid were continuousely redused until the last period. In con trast with the above the content of reducing sugars was increased but the content of crude fat, cellulose, ash, crude protein and soluble non-nitrogen material were increased until last period. 3. The content of vitamin C was richer in the rind than in the flesh, in the Korean species than in the Japanese. 4. Free sugars; xylose, fructose, glucose were richer in the rind than in the flesh. 5. The content of volatile organic acids was richer in the rind than in the flesh. Among them, volatile acids, acetic acid, formic and n-valeric acid were found in the rind and formic acid, acetic acid and propionic acid were deteceed in the flesh. 6. The total content of non-volatile acids was richer in the flesh than in the rind. In the kind of non-volatile acids, citric acid,glutaric acid, malic acid, tartaric acid, oxalic acid, malonic acid, succinic acid and an unknown acid were found in the rind and citric acid, malic acid, succinic acid, oxalic acid, glutaric acid and malonic acid in the flesh. 7. Three kinds of aromatic components: D-limonene, , p-cymene and seven other kinds of unknown aromatic components were detected in neutral essential oils. Among them, D-limonene seemed to be main aromatic component in the fruits. 8. From the above results it is confirmed that both rind and flesh of the ripened fruit could be utilized for food effectively, and unripened fruits are suitable for producing citric acid, ripened fruits are also useful for producing juice.

Process for the preparation of citric acid esters, citric acid or citric acid salts

Abstract: A process is provided for making a triester of citric acid wherein the cyanohydrin of an acetone dicarboxylic acid diester is reacted with 1 to 3 molar equivalents of an aliphatic alcohol having 1 to 4 carbon atoms and at least two molar equivalents of anhydrous hydrogen chloride in an inert halogenated organic solvent for the cyanohydrin diester at not above 50°C. to form an imino ether, removing excess hydrogen chloride, adding water to form a two-phase system, separating the organic and water phases and recovering the resulting triester from the organic phase. The triester may be hydrolyzed into citric acid or a salt of citric acid in an acid or alkaline medium.

Study on the tasty constituents and minerals in Clavariaceae botrytis

Abstract: Tasty constituents such as free amino acids. free organic acids and free sugars and minerals in clavariaceae botrytis were surveyed through the course of this study. The results were as, follows: 1. Isoleucine valine threonine alanine methionine cysteine glutamine histidine glutamic acid and aspartic acid were presented in clavariaceae botrytis, and aspartic acid showed the highest amount. 2. Succinic acid was the major organic acid in clavariaceae botrytis, and also citric acid malic acid and fumaric acid were presented. 3. Clavariaceae botrytis contained fructose, maltose glucose and sucrose ; glucose and sucrose were more than 80% of total sugars. 4. Na K Mg Ca Zn Mn Cu am Fe by atomic absorption spectrometer were detected and assayed. and Al Si Ni Sn Ti Cr Ag Pb B and Sr detected by emission spectrograph. K of these minerals showed the highest amount but very small amount of Ca was presented.