Lithium Lactate Research Articles

Lithium Isotope Effects in Cation Exchange Chromatography of Lithium Lactate in Water-Dimethyl Sulfoxide and Water-Acetone Mixed Solvent Media

Abstract Lithium isotope separation by ion exchange displacement chromatography of lithium lactate in water-dimethyl sulfoxide (DMSO) and water-acetone mixed solvent media at 25 °C was explored. In both the water-DMSO and water-acetone system, the single stage isotope separation factor (S) was a convex function of the mixing ratio of the solvents in the external solution phase; S had its maximum value of 1.00254 at water: DMSO = 25:75 v/v and 1.00182 at water: acetone = 75:25 v/v. Strong correlations of S with solvent partitions between the solution and the exchanger phases were found in both systems, which was qualitatively explainable by considering the lithium isotope distributions between the two phases based on the fundamental lithium isotope effects and the relative affinities of water, DMSO and acetone towards the lithium ion.

HPLC determination of antioxidant synergists and ascorbic acid in some fatty pharmaceuticals, cosmetics and food

A specific and sensitive reverse-phase HPLC method for the quantitative determination of ascorbic acid and antioxidant synergists (1-tartaric acid, citric acid, lactic acid as lithium lactate and EDTA) in fatty pharmaceuticals, cosmetics and food has been developed. Two extraction procedures were used; treatment with hot water, and extraction with water from a hexane dilution of the product. No significant differences between the two procedures were found (p<0.05), except for ascorbic acid. Quantitative determinations were performed using a C-18 column and sulfuric acid (pH 1.95) mobile phase. With detection, at 210 nm, lactic acid overlapped with ascorbic acid, but the former could be readily identified by TLC. Ascorbic acid was detected at 254 nm, when lactic acid (as lithium lactate) did not interfere in the analysis. Mean recoveries for tartaric, citric and lactic acids were in the range 96–101%.

Effects of lactate concentration on hybridoma culture in lactate‐controlled fed‐batch operation

To investigate the effects of lactate on cell growth and antibody production, a new method of maintaining the lactate concentration constant in a fed-batch culture is described. When the pH was initially adjusted by sodium hydroxide, the specific growth rate decreased and specific death rate increased with an increase of lactate concentration. To investigate whether the inhibition was due to the lactate concentration itself or to the osmotic pressure, the effect of the osmotic pressure adjusted by sodium chloride was compared with that of sodium lactate. When the osmotic pressure was adjusted to same condition as that of sodium lactate using sodium chloride, the specific growth data showed the same degree of growth inhibition. It was thus evident that the inhibition to cell growth was mainly due to osmotic pressure while lactate production from glucose was found to be inhibited by the lactate itself compared with sodium chloride. The specific antibody production rate had a maximum value within a certain range of lactate concentration. Moreover, specific antibody production rate had a unified relationship with the kinetic parameter mu, in spite of the different causes of inhibition by lithium lactate and sodium lactate. A certain "trade-off" relationship between growth and antibody production existed at higher growth rates.

Effects of in vivo and in vitro production of lactic acid on ionized, protein-bound, and complex-bound calcium in blood.

We have studied, both in vitro and in vivo, the quantitative effects of lactic acid production on concentrations of ionized calcium, bound calcium, pH, bicarbonate, and albumin. To do so, we examined the effects of addition of aqueous solutions of either hydrochloric acid, lactic acid, or lithium lactate to blood; we studied in vitro accumulation by storing blood sealed in tubes at room temperature for 5 h, then exposing the blood to air; and we induced in vivo production of lactic acid in healthy individuals who climbed stairs for 10 min. Lactic acid evidently affects the ionized, protein-bound, and complex-bound calcium concentrations in the following ways: (a) hydrogen ions from lactic acid bind to protein, which decreases protein-bound calcium; (b) lactate chelates calcium ions from free ionized calcium and protein-bound calcium about equally; and (c) the loss of a millimole of bicarbonate, either by exposure of blood to air or by respiratory alkalosis, results in the release of about 7 mumol of calcium ions, which re-equilibrate with both the protein-bound and ionized calcium. Because lactate apparently removes calcium ions directly from albumin, our study indicates that protein-bound calcium readily provides calcium ions that buffer changes in the concentration of ionized calcium.

Increase of natural killer activity of mouse lymphocytes following in vitro and in vivo treatment with lithium.

The in vivo and in vitro influence of lithium lactate on mouse natural killer activity was investigated. In vitro exposure of effector-target mixture to graded concentrations of lithium did not substantially modify the natural killer activity of mouse splenocytes, untreated or pretreated with cyclophosphamide. However in vitro treatment of effector splenocytes increased the frequency of NK-percursor cells. The in vivo treatment with lithium lactate greatly increased the natural killer activity in intact mice, whereas it did not improve this cytotoxic function in host immunodepressed by cyclophosphamide. These data suggest that lithium salts produce a modulation of natural killer activity of mouse spleen cells, probably through a mechanism involving the increase of the number of NK-precursors in hosts not subjected to cytotoxic chemotherapy.

Energetics of growth of a defined mixed culture of Desulfovibrio vulgaris and Methanosarcina barkeri: maintenance energy coefficient of the sulfate-reducing organism in the absence and presence of its partner.

The maintenance energy coefficient of Desulfovibrio vulgaris was studied by using a chemostat, with Methanosarcina barkeri or sulfate as the electron acceptor; lithium lactate or sodium pyruvate served as the electron donor. The experiments showed that the growth energetics of D. vulgaris or M. barkeri were greatly affected by maintenance energy coefficients. When D. vulgaris grew on lactate or pyruvate medium with sulfate, these coefficients reached 4.40 and 2.80 mM g-1 h-1, respectively; on lactate medium in the presence of M. barkeri the same coefficient reached a value of 2.90 mM g-1 h-1. Results also showed that the increase of the value of the maintenance energy coefficient corresponded to a decrease of the biomass produced. D. vulgaris maximal growth yield values calculated by use of the Pirt equation were slightly higher with M. barkeri (maximal growth yield, 10 g/mol) than with sulfate (maximal growth yield, 7.5 g/mol). This finding could be interpreted by reference to the ATP-generating reactions involved in D. vulgaris growth in the presence of sulfate or M. barkeri.

The determination of bone viability: A histochemical method for identification of lactate dehydrogenase activity in osteocytes in fresh calcified and decalcified sections of human bone

We have developed a technique for assessing bone viability by the histochemical demonstration of lactate dehydrogenase (LDH) activity in osteocytes. Fresh sawn and ground (75 microns) sections were prepared from femoral heads removed at operation from patients with osteoarthritis of the hip. The sections were decalcified overnight in cold 10% EDTA, pH 7.0. LDH activity was shown by the tetrazolium-formazan reaction with nitroblue tetrazolium as indicator and lithium lactate as substrate. Osteocytes were regarded as viable if their cytoplasm stained dark blue, indicating LDH activity; lacunae containing non-viable osteocytes could be identified by interference contrast illumination. Nearly all osteocytes were viable in the samples studied. Small trabecular fragments, such as could be obtained by needle biopsy, were also suitable for staining after grinding to approximately 50 microns. The method should have application both in research and in diagnosis of ischemic bone disease.

Survival of ram testicular spermatozoa [formula omitted][formula omitted]: Effects of glucose, glucose metabolites, rete testis fluid-proteins, selected androgens and phospholipids

The effects of glucose, glucose metabolites, protein-enriched rete testis fluid (RTF), selected androgens and phospholipids on the survival of testicular spermatozoa in vitro have been studied. The oxidative and glycolytic activity, motility and percentage of live cells were the criteria for assessing the viability of the spermatozoa washed free of the substances that had been added during storage. The addition of lithium lactate, sodium lactate and sodium pyruvate but not glucose was beneficial to the survival of testicular spermatozoa. Following 10 to 12 days storage at 4°C with added lactate or pyruvate testicular spermatozoa had a higher glycolytic activity than did control spermatozoa. The respiratory activity of stored testicular spermatozoa was maintained or depressed, depending on the density of spermatozoal suspension during storage. After 10 to 11 days storage in concentrated RTF or after exposure to selected androgens testicular spermatozoa utilized more glucose than after storage with lactate alone. However, this apparent response to androgens and RTF-proteins was the consequence of a higher survival rate of the spermatozoa rather than an increase in the metabolic activity of individual spermatozoa. These results indicate that metabolites of glucose may serve as substrates for spermatozoa in the epididymis while certain androgens and macromolecules occurring in reproductive tract fluids may play important roles in the survival of spermatozoa during their period of maturation in the epididymis.

Automated Enzymatic Determination of L-Lactate in Serum, with Use of a Miniature Centrifugal Anlyzer

We describe an automated enzymatic reaction-rate method for spectrophotometric determination of lactate in serum with a miniature centrifugal analyzer. The L(+) -lactate is selectively oxidized in the presence of lactate dehydrogenase (EC 1.1.1.27) and NAD+ to form NADH, which is measured from its absorption. Reaction rates are determined automatically, and unknown concentrations are calculated from a computer-generated calibration curve with aqueous lithium lactate standards. Lactate concentrations in the range 0.32-1.6 mug/4 mul (80-400 mg/liter) of sample were determined with relative errors and coefficient of variation of 4.8%. Analytical recovery of lactate added to pooled serum was 89-112% (average, 101%). Comparison with a kit ("Rapid Lactate") method gave a correlation coefficient squared of 0.979 over a concentration range of 39-779 mg/liter.

Automated enzymatic determination of L-lactate in serum, with use of a miniature centrifugal analyzer.

Abstract We describe an automated enzymatic reaction-rate method for spectrophotometric determination of lactate in serum with a miniature centrifugal analyzer. The L(+) -lactate is selectively oxidized in the presence of lactate dehydrogenase (EC 1.1.1.27) and NAD+ to form NADH, which is measured from its absorption. Reaction rates are determined automatically, and unknown concentrations are calculated from a computer-generated calibration curve with aqueous lithium lactate standards. Lactate concentrations in the range 0.32-1.6 mug/4 mul (80-400 mg/liter) of sample were determined with relative errors and coefficient of variation of 4.8%. Analytical recovery of lactate added to pooled serum was 89-112% (average, 101%). Comparison with a kit ("Rapid Lactate") method gave a correlation coefficient squared of 0.979 over a concentration range of 39-779 mg/liter.

Tunnelling rotation rate of a weakly hindered methyl group (e.p.r. and ENDOR measurements)

Electron spin resonance spectra and electron nuclear double resonance measurements are presented for free radicals with the structure CH3COHCOO- formed by gamma irradiation of crystals of lithium lactate. The splitting of the ground state due to the tunnelling rotation of the methyl group is found from the temperature dependence of the populations of the split levels which are reflected in the relative heights of constituent lines of the hyperfine structure. The amplitude of the zero-point torsional oscillation is measured from the relative magnitude of hyperfine coupling tensors and the height of the hindering barrier is deduced from the temperature dependence of the ESR spectrum. All the measurements are consistent with a tunnelling splitting of 22+or-5 GHz.

Radiosensitivity of capillary endothelium.

Starting with a subcutaneous air pouch in the rat, a system was developed in which a thin sheet of connecting tissue was partially separated from its surroundings. In a small area that was depleted of blood vessels by freezing, vascular proliferation was induced by the application of a stimulus employing uric acid and lithium lactate. In unirradiated preparations, the depleted area becomes increasingly re-vascularized in 12 days, while in the irradiated preparations there is a paucity of vessels, the degree of reduction depending on the dose of radiation. As a quantitative indication of the “vascular index” the local amount of an intravenously injected tracer was determined. The tracer substance is a fluorescent dye, and quantification was performed by means of a microfluoro-meter. The “vascular index”, as measured by means of microfluorometry, is probably closest to the vascular silhouette. The “survival curve” derived in this way shows a D0 value of about 170 rads, a N value of about 7, and a DQ of about 340 rads. Split-dose experiments with an initial dose of 500 rads, followed after 24 hours by a test-dose, showed a (D2–D1) value of about 290 rads. In contrast to earlier observations, these results seem to indicate that the radiosensitivity of the endothelial cells of capillaries is of the same order of magnitude as that of epithelial cells and cells of supporting tissues.

Lactate Dehydrogenases in Oomycetes

Lactate dehydrogenases [D(-)-lactate: NAD oxidoreductase, E.C. 1.1.1.28] have recently been detected in a number of lower fungi particularly among the Oomycetes (Gleason and Price, 1969; Warren and Mullins, 1969; LeJohn, 1971) and the Chytridiomycetes (Gleason and Price, 1969; LeJohn, 1971). The Oomycetes known to synthesize these enzymes are Apodachlya brachynema (Hildebrand) Pringsheim, Araiospora sp., Sapromyces elongatus (Cornu) Coker, Mindeniella spinospora Kanouse, Rhipidium sp., Aqualinderella fermentans Emerson & Weston, Achlya ambisexualis Raper, Aphanomyces laevis DeBary, Pythium ultimum Trow, and Phytophthora dreschleri Tucker (Gleason and Price, 1969; Warren and Mullins, 1969; LeJohn, 1971; Gleason, unpublished data). The purpose of this study was to compare certain physical and kinetic properties of the lactate dehydrogenases from several of the Oomycetes listed above. The fungi used for this investigation were kindly made available by the following: Pythium ultimum (67-1) by Dr. Joseph Hancock, Department of Plant Pathology, University of California, Berkeley; Aphanomyces laevis (107-52) by Dr. Torgny Unestam, Institute of Physiological Botany, University of Uppsala; and the members of the Leptomitales by Dr. Ralph Emerson, Department of Botany, University of California, Berkeley. The methods for growth of the fungi and for preparation of cellfree extracts were the same as those described by Gleason and Price (1969). The reaction rates were measured spectrophotometrically at room temperature by a Zeiss PMQII spectrophotometer equipped with a strip chart recorder. The standard assay mixture for the backward reaction contained sodium pyruvate (3.3 X 10-4 M), reduced nicotinamide-adenine dinucleotide (NADH) (1.4 x 10-4 M), potassium phosphate buffer (0.1 M, pH 7.0), and enzyme in a final volume of 3.0 ml. The standard assay mixture for the forward reaction contained D(-)lithium lactate (0.1 M), NAD (2.0 X 10-4 M), tris hydrochloride buffer (0.1 M, pH 8.5), and enzyme in a final volume of 3.0 ml. The rate of the reaction was determined by change in absorbance at 340 mu

Characterization of lactate dehydrogenase of Helisoma antrosum (mollusca: basommatophora): Enzyme assays, polyacrylamide-gel electrophoresis and isoelectric focusing

Under the described experimental conditions, lactate dehydrogenase (LDH) of Helisoma antrosum is characterized as follows: 1.1. At low substrate (lithium lactate) concentrations (0·01–0·03 M), LDH of whole snail homogenates appears to display hyperbolic kinetics. At higher substrate concentrations (0·04–0·16 M), LDH displays sigmoid kinetics.2.2. LDH exists as a multiple molecular form displaying five isoenzymes.3.3. A Hill plot of the data for whole snail homogenates indicates that at least one of the LDH isoenzymes possesses at least two interacting binding sites.4.4. Isoelectric focusing demonstrated four molecular forms of LDH, the isoelectric points (pI) of these forms being 3·8, 5·2, 6·2 and 8·5.5.5. The Michaelis constant (apparent Km) of the LDH from whole snail homogenates is 5·5 × 10−2 M.6.6. LDH-4, and possibly LDH-5, correspond to a thick band which had been previously demonstrated with amino black (protein stain) and Ponceau red (lipoprotein stain).7.7. LDH-4 is the predominant band in acrylamide gels.

ESR-resonance in doped GaAs and GaP

The feasibility of lithium lactate (Li-lactate: CH3CH(OH)COOLi) as an electron spin resonance (ESR) dosimeter material has been studied and compared with lactose and a conventional alanine dosimeter. The ESR spectra of Li-lactate and lactose with the spectroscopic splitting g-factors of 2.0029 ± 0.0003 and 2.0043 ± 0.0003 respectively show hyperfine splitting with an intensity ratio of 1:3:3:1 and hyperfine coupling constants (A/gβ) of 1.82 ± 0.06 and 1.88 ± 0.06 mT, respectively. The radical formation efficiency (G-value), i.e. the number of free radicals per 100 eV for alanine, Li-lactate and lactose were 0.95, 1.0 and 3.0, respectively. The sensitivity of Li-lactate to γ-rays is 10 times higher than that of alanine and 0.3 of lactose. The signal stability of Li-lactate was greater than that of lactose.

A method for the determination of the water‐insoluble combined lactic acid content of shortenings containing lactylated emulsifiers

AbstractShortenings containing glycerol lactopalmitates and glycerol lactostearates are analyzed for water‐insoluble combined lactic acid content using a procedure adapted from that of Barker and Summerson (1). Water‐soluble constituents are extracted from a chloroform solution of the shortening. The water‐washed shortening is saponified and then acidified to release the lactic acid, which is degraded to acetaldehyde by heating with concentrated sulfuric acid. The acetaldehyde is reacted withp‐phenyl phenol is concentrated acid solution to produce a purple colored reaction product. The intensity of the color is proportional to the concentration of the acetaldehyde. Absorption is read at 570 mॖ using a lithium lactate solution as a standard.The method has been applied to the analysis of shortenings containing from 0.70 to 1.10% water‐insoluble combined lactic acid.