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Journal of Dairy Science Sep 2011The range of sodium chloride (salt)-to-moisture ratio is critical in producing high-quality cheese products. The salt-to-moisture ratio has numerous effects on cheese...
The range of sodium chloride (salt)-to-moisture ratio is critical in producing high-quality cheese products. The salt-to-moisture ratio has numerous effects on cheese quality, including controlling water activity (a(w)). Therefore, when attempting to decrease the sodium content of natural cheese it is important to calculate the amount of replacement salts necessary to create the same a(w) as the full-sodium target (when using the same cheese making procedure). Most attempts to decrease sodium using replacement salts have used concentrations too low to create the equivalent a(w) due to the differences in the molecular weight of the replacers compared with salt. This could be because of the desire to minimize off-flavors inherent in the replacement salts, but it complicates the ability to conclude that the replacement salts are the cause of off-flavors such as bitter. The objective of this study was to develop a model system that could be used to measure a(w) directly, without manufacturing cheese, to allow cheese makers to determine the salt and salt replacer concentrations needed to achieve the equivalent a(w) for their existing full-sodium control formulas. All-purpose flour, salt, and salt replacers (potassium chloride, modified potassium chloride, magnesium chloride, and calcium chloride) were blended with butter and water at concentrations that approximated the solids, fat, and moisture contents of typical Cheddar cheese. Salt and salt replacers were applied to the model systems at concentrations predicted by Raoult's law. The a(w) of the model samples was measured on a water activity meter, and concentrations were adjusted using Raoult's law if they differed from those of the full-sodium model. Based on the results determined using the model system, stirred-curd pilot-scale batches of reduced- and full-sodium Cheddar cheese were manufactured in duplicate. Water activity, pH, and gross composition were measured and evaluated statistically by linear mixed model. The model system method accurately determined the concentrations of salt and salt replacer necessary to achieve the same a(w) as the full-sodium control in pilot-scale cheese using different replacement salts.
Topics: Calcium Chloride; Cheese; Food Handling; Magnesium Chloride; Models, Theoretical; Potassium Chloride; Sodium Chloride; Sodium, Dietary; Water
PubMed: 21854908
DOI: 10.3168/jds.2011-4359 -
European Journal of Histochemistry : EJH Nov 2021Oxaliplatin is a third-generation chemotherapy drug mainly used for colorectal cancer treatment. However, it is also known to trigger neuropathy whose underlying...
Oxaliplatin is a third-generation chemotherapy drug mainly used for colorectal cancer treatment. However, it is also known to trigger neuropathy whose underlying neurobiological mechanisms are still under investigation and currently available treatments show limited efficacy. It is now established that neurons are not the only cell type involved in chronic pain and that glial cells, mainly astrocytes and microglia, are involved in the initiation and maintenance of neuropathy. Among all the pathogenetic factors involved in neuropathic pain, an oxaliplatin-dependent oxidative stress plays a predominant role. In our study, the antioxidant properties of magnesium (Mg), manganese (Mn) and zinc (Zn) salts were evaluated in order to counteract microglial activation induced by oxaliplatin. The antioxidant efficacy of these metals was evaluated by the means of molecular and morphological assays on the BV-2 microglial cell line. Our data clearly show that Mg, Mn and Zn are able to prevent oxaliplatin-dependent microglial alterations by reducing both oxidative and endoplasmic reticulum stress.
Topics: Animals; Antioxidants; B7-2 Antigen; Calcium-Binding Proteins; Cell Line; Chlorides; Endoplasmic Reticulum Stress; Magnesium Chloride; Manganese Compounds; Mice; Microfilament Proteins; Microglia; Oxaliplatin; Oxidative Stress; Reactive Oxygen Species; Zinc Compounds
PubMed: 34755507
DOI: 10.4081/ejh.2021.3285 -
PloS One 2014Polymerase chain reaction (PCR) is an in vitro technology in molecular genetics that progressively amplifies minimal copies of short DNA sequences in a fast and...
Polymerase chain reaction (PCR) is an in vitro technology in molecular genetics that progressively amplifies minimal copies of short DNA sequences in a fast and inexpensive manner. However, PCR performance is sensitive to suboptimal processing conditions. Compromised PCR conditions lead to artifacts and bias that downgrade the discriminatory power and reproducibility of the results. Promising attempts to resolve the PCR performance optimization issue have been guided by quality improvement tactics adopted in the past for industrial trials. Thus, orthogonal arrays (OAs) have been employed to program quick-and-easy structured experiments. Profiling of influences facilitates the quantification of effects that may counteract the detectability of amplified DNA fragments. Nevertheless, the attractive feature of reducing greatly the amount of work and expenditures by planning trials with saturated-unreplicated OA schemes is known to be relinquished in the subsequent analysis phase. This is because of an inherent incompatibility of ordinary multi-factorial comparison techniques to convert small yet dense datasets. Treating unreplicated-saturated data with either the analysis of variance (ANOVA) or regression models destroys the information extraction process. Both of those mentioned approaches are rendered blind to error since the examined effects absorb all available degrees of freedom. Therefore, in lack of approximating an experimental uncertainty, any outcome interpretation is rendered subjective. We propose a profiling method that permits the non-linear maximization of amplicon resolution by eliminating the necessity for direct error estimation. Our approach is distribution-free, calibration-free, simulation-free and sparsity-free with well-known power properties. It is also user-friendly by promoting rudimentary analytics. Testing our method on published amplicon count data, we found that the preponderant effect is the concentration of MgCl2 (p<0.05) followed by the primer content (p<0.1) whilst the effects due to either the content of the deoxynucleotide (dNTP) or DNA remained dormant (p>0.1). Comparison of the proposed method with other stochastic approaches is also discussed. Our technique is expected to have extensive applications in genetics and biotechnology where there is a demand for cheap, expedient, and robust information.
Topics: Algorithms; DNA; DNA Primers; Magnesium Chloride; Polymerase Chain Reaction
PubMed: 25269015
DOI: 10.1371/journal.pone.0108973 -
Cell Stress & Chaperones Jan 2016Seventy-kilodalton heat shock proteins (Hsp70s) are molecular chaperones essential for maintaining cellular homeostasis. Apart from their indispensable roles in protein...
Seventy-kilodalton heat shock proteins (Hsp70s) are molecular chaperones essential for maintaining cellular homeostasis. Apart from their indispensable roles in protein homeostasis, specific Hsp70s localize at the plasma membrane and bind to specific lipids. The interaction of Hsp70s with lipids has direct physiological outcomes including lysosomal rescue, microautophagy, and promotion of cell apoptosis. Despite these essential functions, the Hsp70-lipid interactions remain largely uncharacterized. In this study, we characterized the interaction of HspA1A, an inducible Hsp70, with five phospholipids. We first used high concentrations of potassium and established that HspA1A embeds in membranes when bound to all anionic lipids tested. Furthermore, we found that protein insertion is enhanced by increasing the saturation level of the lipids. Next, we determined that the nucleotide-binding domain (NBD) of the protein binds to lipids quantitatively more than the substrate-binding domain (SBD). However, for all lipids tested, the full-length protein is necessary for embedding. We also used calcium and reaction buffers equilibrated at different pH values and determined that electrostatic interactions alone may not fully explain the association of HspA1A with lipids. We then determined that lipid binding is inhibited by nucleotide-binding, but it is unaffected by protein-substrate binding. These results suggest that the HspA1A lipid-association is specific, depends on the physicochemical properties of the lipid, and is mediated by multiple molecular forces. These mechanistic details of the Hsp70-lipid interactions establish a framework of possible physiological functions as they relate to chaperone regulation and localization.
Topics: Adenosine Diphosphate; Adenosine Triphosphate; Animals; Binding Sites; Calcium Chloride; Cell Membrane; HSP70 Heat-Shock Proteins; Magnesium Chloride; Mice; Molecular Dynamics Simulation; Phospholipids; Polymerase Chain Reaction; Potassium Chloride; Protein Binding; Protein Structure, Tertiary
PubMed: 26342809
DOI: 10.1007/s12192-015-0636-6 -
Antimicrobial Agents and Chemotherapy Jul 1999Analogues based on the insect cecropin-bee melittin hybrid peptide (CEME) were studied and analyzed for activity and salt resistance. The new variants were designed to...
Analogues based on the insect cecropin-bee melittin hybrid peptide (CEME) were studied and analyzed for activity and salt resistance. The new variants were designed to have an increase in amphipathic alpha-helical content (CP29 and CP26) and in overall positive charge (CP26). The alpha-helicity of these peptides was demonstrated by circular dichroism spectroscopy in the presence of liposomes. CP29 was shown to have activity against gram-negative bacteria that was similar to or better than those of the parent peptides, and CP26 had similar activity. CP29 had cytoplasmic membrane permeabilization activity, as assessed by the unmasking of cytoplasmic beta-galactosidase, similar to that of CEME and its more positively charged derivative named CEMA, whereas CP26 was substantially less effective. The activity of the peptides was not greatly attenuated by an uncoupler of membrane potential, carbonyl cyanide-m-chlorophenylhydrazone. The tryptophan residue in position 2 was shown to be necessary for interaction with cell membranes, as demonstrated by a complete lack of activity in the peptide CP208. Peptides CP29, CEME, and CEMA were resistant to antagonism by 0.1 to 0.3 M NaCl; however, CP26 was resistant to antagonism only by up to 160 mM NaCl. The peptides were generally more antagonized by 3 and 5 mM Mg2+ and by the polyanion alginate. It appeared that the positively charged C terminus in CP26 altered its ability to permeabilize the cytoplasmic membrane of Escherichia coli, although CP26 maintained its ability to kill gram-negative bacteria. These peptides are potential candidates for future therapeutic drugs.
Topics: Alginates; Amino Acid Sequence; Animals; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Carrier Proteins; Cell Membrane Permeability; Glucuronic Acid; Hexuronic Acids; Magnesium Chloride; Mice; Microbial Sensitivity Tests; Molecular Sequence Data; Protein Structure, Secondary; Recombinant Proteins; Sodium Chloride; Structure-Activity Relationship
PubMed: 10390200
DOI: 10.1128/AAC.43.7.1542 -
Journal of Medicinal Food Jun 2012Drinking deep seawater (DSW) with high levels of magnesium (Mg) decreased serum lipids in animal studies. Therefore the effects of drinking DSW on blood lipids and its... (Randomized Controlled Trial)
Randomized Controlled Trial
Drinking deep seawater (DSW) with high levels of magnesium (Mg) decreased serum lipids in animal studies. Therefore the effects of drinking DSW on blood lipids and its antioxidant capacity in hypercholesterolemic subjects were investigated. DSW was first prepared by a process of filtration and reverse osmosis, and then the concentrated DSW with high levels of Mg was diluted as drinking DSW. Forty-two hypercholesterolemic volunteers were randomly divided into three groups: reverse osmotic (RO) water, DSW (Mg: 395 mg/L, hardness 1410 ppm), and magnesium-chloride fortified (MCF) water (Mg: 386 mg/L, hardness 1430 ppm). The subjects drank 1050 mL of water daily for 6 weeks, and blood samples were collected and analyzed on weeks 0, 3, and 6. Drinking DSW caused a decrease in blood total cholesterol levels and this effect was progressively enhanced with time. Serum low-density lipoprotein-cholesterol (LDL-C) was also decreased by DSW. Further, total cholesterol levels of subjects in the DSW group were significantly lower than those in the MCF water or RO water groups. Compared with week 0, the DSW group had higher blood Mg level on weeks 3 and 6, but the Mg levels were within the normal range in all three groups. DSW consumption also lowered thiobarbituric acid-reactive substances (TBARS) values in serum. In conclusion, DSW was apparently effective in reducing blood total cholesterol and LDL-C, and also in decreasing lipid peroxidation in hypercholesterolemic subjects.
Topics: Adult; Anticholesteremic Agents; Antioxidants; Cholesterol; Cholesterol, LDL; Female; Filtration; Humans; Hypercholesterolemia; Magnesium; Magnesium Chloride; Male; Middle Aged; Osmosis; Seawater; Thiobarbituric Acid Reactive Substances
PubMed: 22424458
DOI: 10.1089/jmf.2011.2007 -
Proceedings of the National Academy of... Dec 2000We have found that divalent electrolyte counterions common in biological cells (Ca(2+), Mg(2+), and Mn(2+) ) can condense anionic DNA molecules confined to...
We have found that divalent electrolyte counterions common in biological cells (Ca(2+), Mg(2+), and Mn(2+) ) can condense anionic DNA molecules confined to two-dimensional cationic surfaces. DNA-condensing agents in vivo include cationic histones and polyamines spermidine and spermine with sufficiently high valence (Z) 3 or larger. In vitro studies show that electrostatic forces between DNA chains in bulk aqueous solution containing divalent counterions remain purely repulsive, and DNA condensation requires counterion valence Z >/= 3. In striking contrast to bulk behavior, synchrotron x-ray diffraction and optical absorption experiments show that above a critical divalent counterion concentration the electrostatic forces between DNA chains adsorbed on surfaces of cationic membranes reverse from repulsive to attractive and lead to a chain collapse transition into a condensed phase of DNA tethered by divalent counterions. This demonstrates the importance of spatial dimensionality to intermolecular interactions where nonspecific counterion-induced electrostatic attractions between the like-charged polyelectrolytes overwhelm the electrostatic repulsions on a surface for Z = 2. This new phase, with a one-dimensional counterion liquid trapped between DNA chains at a density of 0.63 counterions per DNA bp, represents the most compact state of DNA on a surface in vitro and suggests applications in high-density storage of genetic information and organo-metallic materials processing.
Topics: Bacteriophage lambda; Cations, Divalent; Chlorides; Cobalt; DNA; DNA, Viral; Fatty Acids, Monounsaturated; Lipid Bilayers; Magnesium Chloride; Manganese Compounds; Models, Molecular; Nucleic Acid Conformation; Phosphatidylcholines; Quaternary Ammonium Compounds; Spermidine; Spermine
PubMed: 11121015
DOI: 10.1073/pnas.97.26.14046 -
British Journal of Pharmacology and... Mar 1959In rats kept on a low-potassium diet that contains only maintenance levels of magnesium, cardiac necroses and muscular cramps were readily induced by the oral...
In rats kept on a low-potassium diet that contains only maintenance levels of magnesium, cardiac necroses and muscular cramps were readily induced by the oral administration of sodium perchlorate or disodium hydrogen phosphate. The precipitation of these cardiac and skeletal muscle changes by sodium chlorate was prevented by the prophylactic administration of either potassium or magnesium chlorides. The protective effect of these chlorides against the cardiotoxic and convulsive effects of disodium hydrogen phosphate has already been demonstrated by our earlier experiments. Sodium sulphate produced cardiac necroses in rats maintained on the same diet, and both potassium and magnesium chlorides had a prophylactic action. Unlike sodium perchlorate, however, sodium sulphate produced no muscular cramps under these conditions. Equimolecular amounts of sodium given in the form of sodium chloride (instead of sodium perchlorate, sodium sulphate, or disodium hydrogen phosphate) did not cause cardiac necroses or muscular cramps in rats maintained on the potassium-deficient diet. As the same three sodium salts, namely the perchlorate, the sulphate, and the hydrogen phosphate, produced cardiac necroses in rats sensitized by either a potassium-deficient diet or by certain corticoids, it seems that the anion must play a decisive rôle, since equivalent amounts of NaCl are ineffective.
Topics: Animals; Chlorides; Electrolytes; Heart; Magnesium; Magnesium Chloride; Muscle, Skeletal; Muscles; Pharmaceutical Preparations; Phosphates; Potassium; Rats; Sodium; Sodium Chloride
PubMed: 13651583
DOI: 10.1111/j.1476-5381.1959.tb00932.x -
Journal of Dairy Science Jun 2012The use of mineral salt replacers to reduce the sodium content in cheese has been investigated as a method to maintain both the salty flavor and the preservative effects...
The use of mineral salt replacers to reduce the sodium content in cheese has been investigated as a method to maintain both the salty flavor and the preservative effects of salt. The majority of studies of sodium reduction have used mineral salt replacers at levels too low to produce equal water activity (a(w)) in the finished cheese compared with the full-sodium control. Higher a(w) can result in differences in cheese quality due to differences in the effective salt-to-moisture ratio. This creates differences in biochemical and microbial reactions during aging. We hypothesized that by targeting replacer concentrations to produce the same a(w) as full sodium cheese, changes in cheese quality would be minimized. Stirred-curd Cheddar-style cheese was manufactured and curd was salted with NaCl or naturally reduced sodium sea salt. Reduced-sodium cheeses were created by blends of NaCl or sea salt with KCl, modified KCl, MgCl₂, or CaCl₂ before pressing. Sodium levels in reduced-sodium cheeses ranged from 298 to 388 mg of sodium/100g, whereas the control full-sodium cheese had 665 mg/100g. At 1 wk of age, a(w) of reduced-sodium cheeses were not significantly different from control, which had an a(w) of 0.96. The pH values of all reduced-sodium cheeses, excluding the treatment that combined sea salt and MgCl₂, were lower than those of full-sodium cheese, indicating that the starter culture was possibly less inhibited at the salting step by the replacers than by NaCl. Instrumental hardness values of the treatments with sea salt were higher than in cheeses containing NaCl, with the exception of the NaCl/CaCl₂ treatment, which was the hardest. Treatments with MgCl₂ and modified KCl were generally less hard than other treatments. In-hand and first-bite firmness values correlated with the instrumental texture profile analysis results. Both CaCl₂ and MgCl₂ produced considerable off-flavors in the cheese (bitter, metallic, unclean, and soapy), as measured by descriptive sensory analysis with a trained panel. Bitterness ratings for cheese with KCl and modified KCl were not significantly different from the full-sodium control. Potassium chloride can be used successfully to achieve large reductions in sodium when replacing a portion of the NaCl in Cheddar cheese.
Topics: Calcium Chloride; Cheese; Diet, Sodium-Restricted; Food Technology; Magnesium Chloride; Potassium Chloride; Sodium, Dietary
PubMed: 22612920
DOI: 10.3168/jds.2011-4851 -
Scientific Reports May 2021Kokumi taste is a well-accepted and characterised taste modality and is described as a sensation of enhancement of sweet, salty, and umami tastes. The Calcium Sensing...
Kokumi taste is a well-accepted and characterised taste modality and is described as a sensation of enhancement of sweet, salty, and umami tastes. The Calcium Sensing Receptor (CaSR) has been designated as the putative kokumi taste receptor for humans, and a number of kokumi-active ligands of CaSR have been discovered recently with activity confirmed both in vivo and in vitro. Domestic cats (Felis catus) are obligate carnivores and accordingly, their diet is abundant in proteins, peptides, and amino acids. We hypothesised that CaSR is a key taste receptor for carnivores, due to its role in the detection of different peptides and amino acids in other species. Using in silico, in vitro and in vivo approaches, here we compare human CaSR to that of a model carnivore, the domestic cat. We found broad similarities in ligand specificity, but differences in taste sensitivity between the two species. Indeed our in vivo data shows that cats are sensitive to CaCl as a kokumi compound, but don't show this same activity with Glutathione, whereas for humans the reverse is true. Collectively, our data suggest that kokumi is an important taste modality for carnivores that drives the palatability of meat-derived compounds such as amino acids and peptides, and that there are differences in the perception of kokumi taste between carnivores and omnivores.
Topics: Amino Acid Sequence; Amino Acids; Animals; Calcium Chloride; Cats; Glutathione; Humans; Ligands; Magnesium Chloride; Meat Products; Peptides; Protein Binding; Receptors, Calcium-Sensing; Taste Buds; Taste Perception
PubMed: 34006911
DOI: 10.1038/s41598-021-89558-w