Where Can I Buy Glycerol
The Glycerol GK test kit is a simple, reliable and accurate method for the measurement and analysis of glycerol in beverages, foodstuffs and other material. Based on use of ADP-glucokinase and increase in absorbance on conversion of NAD+ to NADH.
where can i buy glycerol
One of the most promising avenues of biofuel research relates to using waste as a starting feedstock to produce liquid or gaseous energy carriers. The global production of waste glycerol by the refinery industry is rising year after year. The aim of the present study was to examine the effect of ethyl methane sulfonate (EMS) on the growth rates and intracellular lipid accumulation in heterotrophically-cultured Schizochytrium limacinum microalgae, grown on waste glycerol as the carbon source. The strain S. limacinum E20, produced by incubating a reference strain in EMS for 20 min, was found to perform the best in terms of producing biomass (0.054 gDW/dm3h) and accumulating intracellular bio-oil (0.021 g/dm3h). The selected parameters proved to be optimal for S. limacinum E20 biomass growth at the following values: temperature 27.3 C, glycerol level 249.0 g/dm3, oxygen in the culture 26%, and yeast extract concentration 45.0 g/dm3. In turn, the optimal values for lipid production in an S. limacinum E20 culture were: temperature 24.2 C, glycerol level 223.0 g/dm3, oxygen in the culture 10%, and yeast extract concentration 10.0 g/dm3. As the process conditions are different for biomass growth and for intracellular lipid accumulation, it is recommended to use a two-step culture process, which resulted in a lipid synthesis rate of 0.41 g/dm3h.
The performance of fermentation under sub-lethal high pressure (HP) is a strategy for stimulation of microbial growth and/or improvement of fermentation titers, rates and yields. The present work intended to study the possibility of applying HP to Paracoccus denitrificans glycerol fermentation, considering that HP-fermentation usually involves some process constrains, such as limited air volumes. Consequently, the work was divided in two main goals: i) study the effects of air availability on P. denitrificans; ii) assess if the strain is able to grow and maintain metabolic activity under HP (10-35 MPa). Paracoccus denitrificans growth and metabolism were highly affected by air availability. Samples under higher air availability showed considerable cell growth, but no production of ethanol or organic acids. On the other hand, samples without air had lower cell growth, but active metabolic activity (with the production of ethanol and organic acids). Regarding the HP experiments, P. denitrificans was able to grow at 10, 25 and 35 MPa, but to a lower extent compared to atmospheric pressure. Application of HP promoted modifications in the production of ethanol, acetate and succinate, and the fermentative profile varied according to the pressure level. Overall, the present work demonstrated new metabolic features of P. denitrificans at atmospheric pressure and HP conditions. It also opened the way for further studies regarding P. denitrificans fermentation under HP, as well as utilization of this technology for other glycerol fermentations, in particular in the case of high requirements of air availability.
Emulsifiers of the type E 472 are esters of fruit acids and mono- and diacylglycerols (MAG and DAG), which are used to adjust techno-functional properties in various food products. The most dominant representatives of E 472 emulsifiers are acetic acid esters (E 472a), lactic acid esters (E 472b), citric acid esters (E 472c), and mono- and diacetyl tartaric acid esters (E 472e). For the determination of fruit acids, a high-performance liquid chromatography method with ultraviolet light (HPLC-UV) detection was developed. Free and total fruit acids were determined by reversed phase HPLC-UV analysis of untreated and saponified emulsifier extracts with 20 mM potassium hydrogen phosphate buffer (pH 2.6) as isocratic eluent. Limits of quantitation of 0.08-0.27 g free fruit acid/kg emulsifier and 4-14 g total fruit acid/kg granted a reliable method with recoveries for free and total fruit acids between 80 and 100% with relative standard deviations (%RSD) below 4%. For the quantitation of free glycerol by spectrophotometry, an enzymatic assay was optimized for the analysis of E 472 providing reliable results with %RSD values below 9%. In addition, the ash content of E 472 emulsifiers was determined.
The performance of fermentation under non-conventional conditions, such as high pressure (HP), is a strategy currently tested for different fermentation processes. In the present work, the purpose was to apply HP (10-50 MPa) to fermentation by Paracoccus denitrificans, a microorganism able to produce polyhydroxyalkanoates (PHA) from glycerol. In general, cell growth and glycerol consumption were both reduced by HP application, more extensively at higher pressure levels, such as 35 or 50 MPa. PHA production and composition was highly dependent on the pressure applied. HP was found to decrease polymer titers, but increase the PHA content in cell dry mass (%), indicating higher ability to accumulate these polymers in the cells. In addition, some levels of HP affected PHA monomeric composition, with the polymer produced at 10 and 35 MPa showing considerable differences relative to the ones obtained at atmospheric pressure. Therefore, it is possible to foresee that the changes in polymer composition may also affect its physical and mechanical properties. Overall, the results of this study demonstrated that HP technology (at specific levels) can be applied to P. denitrificans fermentations without compromising the ability to produce PHA, with potentially interesting effects on polymer composition.
Zooxanthellate corals have long been known to calcify faster in the light than in the dark, however the mechanism underlying this process has been uncertain. Here we tested the effects of oxygen under controlled pCO2 conditions and fixed carbon sources on calcification in zooxanthellate and bleached microcolonies of the branching coral Stylophora pistillata. In zooxanthellate microcolonies, oxygen increased dark calcification rates to levels comparable to those measured in the light. However in bleached microcolonies oxygen alone did not enhance calcification, but when combined with a fixed carbon source (glucose or glycerol), calcification increased. Respiration rates increased in response to oxygen with greater increases when oxygen is combined with fixed carbon. ATP content was largely unaffected by treatments, with the exception of glycerol which decreased ATP levels.
To improve wine taste and flavor stability, a novel indigenous strain of Saccharomyces cerevisiae with enhanced glycerol and glutathione (GSH) production for winemaking was constructed. ALD6 encoding an aldehyde dehydrogenases of the indigenous yeast was replaced by a GPD1 and CUP1 gene cassette, which are responsible for NAD-dependent glycerol-3-phosphatase dehydrogenase and copper resistance, respectively. Furthermore, the α-acetohydroxyacid synthase gene ILV2 of the indigenous yeast was disrupted by integration of the GSH1 gene which encodes γ-glutamylcysteine synthetase and the CUP1 gene cassette. The fermentation capacity of the recombinant was similar to that of the wild-type strain, with an increase of 21 and 19% in glycerol and GSH production. No heterologous DNA was harbored in the recombinant in this study.
Native pertussis toxin is provided as a consistent product in three different formulations. Pertussis toxin is lyophilized either in buffer (Product # 180) or in pure water (Product # 181). Additionally, pertussis toxin is sold in a glycerol solution (Product # 179). These products are listed below.
Pertussis toxin is a multi-component protein composed of six non-covalently bound subunits ranging in molecular weight from approximately 9 to 28 kDa. These subunits are designated as S1, S2, S3, S4 and S5 and occur in native pertussis toxin in a ratio of 1:1:1:2:1, where the subunit S4 is present in two copies. The largest subunit S1, also called the A protomer, is responsible for the ADP-ribosyltransferase activity; the A protomer alone will transfer the ADP ribose from NAD+ to α subunits of G proteins of the class Gαi, Gαo or Gαt. The crystal structure of PTX reveals a pyramid-like shape with the A protomer situated on top of the S5 subunit which rests on two dimers, S2-S4 and S3-S4. Together the five subunit platform is called the B oligomer and under certain conditions PTX dissociates into just two parts, the enzymatic A protomer and the five subunit, binding complex, the B oligomer. This B oligomer allows PTX to enter most cells, attaching to glycan residues present on receptor proteins including TLR4 and glycoprotein Ib. After entering the cell via receptor-mediated endocytosis, PTX is transported retrogradely via the endosomal pathway and Golgi complex to the endoplasmic reticulum. A protomer is released from the toxin and translocates through the membrane of the endoplasmic reticulum where the toxin inactivates the target membrane-bound G proteins.
PGSA is a bioresorbable polymer with tunable physical properties ranging from an elastomer to a thermoset. It is derived from glycerol and sebacic acid, both of which are naturally occurring metabolites and have been used for biomedical applications regulated by the FDA. In addition, PGSA is light-sensitive and can be crosslinked under exposure of UV and visible light. Due to its great biocompatibility and excellent mechanical properties, PGSA can be used for various applications in tissue engineering and regenerative medicine (e.g. cardiac, nerve, and muscle tissues).
Bacterial glycerol stocks are important for long-term storage of plasmids. Although you can store your plasmid DNA at -20C, many labs also create bacterial glycerol stocks of their plasmids. This way, when you want to make more plasmid DNA, the plasmid will already be in your desired bacterial strain and you will not need to obtain more competent cells and retransform. 041b061a72