Anaerobic growth of Klebsiella aerogenes NCDO 711 (NCTC 418) on citrate was dependent on the presence of Na+ in the medium, and fermentation of citrate was mediated via the fermentation pathway enzymes, citrate lyase and a Na+-dependent oxalacetate decarboxylase. This confirms the previous findings on strain NCTC 418. Growth under aerobic conditions was independent of Na+. The mean generation t...

Diluents based on the zwitterion buffers Tes, Hepes and Pipes titrated to pH 7.0 with NaOH or Tris were compared with Tris-citrate diluents by assessment of post-thawing motility and acrosome integrity of frozen ram spermatozoa. Varying buffer osmolalities between 300 and 360 mosmol had no effect but there was a decrease (P < 0.001) in motility between 360 and 420 mosmol. There was a quadratic ...

The objective of this study was to evaluate quality of frozen-thawed bull semen processed with extenders containing vitamin C and E as antioxidants. Pooled semen's were collected from 5 bulls and diluted to a concentration of 30 × 106 sperm/mL with citrate –egg yolk (CEY) or Tris – egg yolk (TEY) extenders. The diluted semen was divided to 5 aliquots including control and 4 experimental groups....

Potassium citrate (10 mM, pH 6) inhibits the growth of cultured (Glycine max L.) cells when urea is the sole nitrogen source. Ureadependent citrate toxicity is overcome by three separate additions to the growth medium: (a) NH(4)Cl (20 mM); (b) high levels of MgCl(2) (10 mM) or CaCl(2) (5-10 mM); (c) low levels of NiSO(4) (10(-2) mM). Additions of 10(-2) mM NiSO(4) not only overcome citrate grow...

Studying the thermophysical properties of disaccharide based ternary solutions are gaining increasing importance because of their role as excepients in preservation protocols for biologics in general and mammalian cells in particular. Preservation strategies involve not only cryopreservation, but novel approaches like room temperature vitrification and lyophilization. In this study we investiga...

There are rising public health concerns about the links between consumption of sugar-sweetened beverages and weight gain, obesity, and other metabolic problems. Sodium citrate (Na-citrate) is used as an additive in colas and various commercial drinks worldwide. Although potassium citrate (K-citrate) has been prescribed and well accepted by urologists for treating urinary stone disease (urolithi...

the objective of this study was to evaluate quality of frozen-thawed bull semen processed with extenders containing vitamin c and e as antioxidants. pooled semen's were collected from 5 bulls and diluted to a concentration of 30 × 106 sperm/ml with citrate –egg yolk (cey) or tris – egg yolk (tey) extenders. the diluted semen was divided to 5 aliquots including control and 4 experimental groups....

A rapid analytical method for the simultaneous determination of 12 different organotin compounds (OTC): methyl-, butyl-, phenyl- and octyl-tins in natural water samples was developed. It comprises of in situ derivatisation (by using NaBEt4) of OTC in salty or fresh water sample matrix adjusted to pH 6 with Tris-citrate buffer, extraction of ethylated OTC into hexane, separation of OTC in organi...

We describe a method for determining fluoride with ion-selective electrodes (ISEs). Tartrate and Tris-based total ionic strength adjustment buffers (TISABs) were found to lower the interference from aluminum to a greater extent than conventional citrate-based TISABs. We adopted a solid TISAB addition method that is simple to perform, and can be carried out without lowering the level of fluoride...

Citrate metabolism by Enterococcus faecium FAIR-E 198, an isolate from Greek Feta cheese, was studied in modified MRS (mMRS) medium under different pH conditions and glucose and citrate concentrations. In the absence of glucose, this strain was able to metabolize citrate in a pH range from constant pH 5.0 to 7.0. At a constant pH 8.0, no citrate was metabolized, although growth took place. The ...