Digestion media

Differential pulse anodic scanning voltammetry has been applied to the determination of lead in soils [119]. Sakharov [120] determined lead in soil polarographically by digesting the sample with sodium carbonate, followed by dissolution in hydrochloric acid. He found that when hydrochloric, sulfuric or nitric acids were used as digestion media instead of sodium carbonate, no lead could be detected in the resulting solution. Lead was determined in the digest by anodic scanning voltammetry [121]. 

Tryptic soya broth (soybean-casein digest medium) for normal media fill run... 

For the multispecies determination of a maximum of four species like inorganic Hg2+, Me-Hg, ethyl-Hg, and phenyl-Hg an automatic system was devised based on the on-line coupling of HPLC with CV-AFS via a postcolumn MW digestion. The digestion medium was K2S208 in HC1. Parameters influencing on-line digestion efficiency and the separation effects were optimized, which allowed for the separation of the four Hg species within 13 min. The absolute LoDs were 0.3 ng for Hg2+, 0.2 ng for Me-Hg, 0.17 ng for ethyl-Hg, and 0.14 ng for phenyl-Hg+ [63]. 

In the digestive tract, genetically modified microorganisms can either carry out a reaction of bioconversion or produce compounds of interest. The bioconversion reaction can lead either to the production of an active product or to the removal of undesirable compounds. The active compound produced in situ can be secreted in the digestive medium [5], be bound to the cells [6,7], or accumulate inside the cells and be released in the digestive environment by cell lysis [8]. 

Probes supply more powerful energy also. In the absence of highly reactive chemicals, the tip can be directly Inserted Into the digestion medium. 

Application field Analytes Sample Digestion medium Digestion time (min) Reference... 

Captex Partially digestible Medium-chain triacylglycerol ABITEC Co. (Columbus, Ohio)... 

In the membrane filtration method, the product samples are put aseptically into a volume of non-inhibitory diluent and then passed through a sterile 0.45 pm membrane filter (Fig. 1). The membrane is rinsed through with additional volumes of diluent, then aseptically cut in half. Half is transferred to a container of soybean casein digest medium (SCDM) and the other to fluid thioglycollate medium (FTM). 

Sterility tests are normally performed by incubating the sample with fluid thioglycollate medium at 30-35° C for 14 days or with soybean-casein digest medium at 20-25° C for 14 days. The sample volume should be as large as that for human dosage. If bacterial growth is observed in either test, the preparation is considered asterile. For PET radiopharmaceuticals, these tests must be started within 24 h after the release of the product. 

C with a digesting medium comprising a mixture of phthalic anhydride and diethylene glycol.37 The resulting polyol-rich products are said to be useful in the preparation of polyurethane and polyisocyanurate foams. 

Doolan and coworkers [18] used three compendial recovery conditions to construct survival curves for naturally contaminated medical devices soybean casein digest medium incubated at 20-25 C, the same incubated at 30-35 C. and fluid ihioglycollatc medium incubated at 30-35 C for 14 days. Three tests for sterility therefore constituted the basis for observing the presence of viable microorganisms in three replicate conditions making up one sample. 

Frieben et al. [2] filled vials with Soybean Casein Digest Medium, sealed them, and then immersed them inverted in a suspension of 10 Escherichia coli... 

A mixture of nitric, sulfuric, and perchloric acids in the ratio of 3 l l(v/v) is a generally useful and very efficient digestion medium for biological materials, but it must be used with caution with samples containing lead. Gorsuch has found that lead is lost when digested in the presence of sulfuric acid by coprecipitation as lead sulfate on other sulfates, usually calcium sulfate. Therefore, a mixture of nitric and perchloric acids is recommended. This mixture must be used with more caution because, in the absence of sulfuric acid, it can be evaporated to near dryness with the danger of explosion. 

Figure 7. Mixed micelles carry the solubilized hydrophobic lipids through the aqueous digest medium into close proximity with the intestinal mucosal cells (enterocytes). Micelles are not absorbed intact, but the various components are taken up by the enterocytes at independent rates. Intracellular esterification of cholesterol by acyl-coenzyme A prevents its transport back to the intestinal lumen. After esterification, cholesterol esters are assembled into chylomicrons and secreted into the lymjiiatic system and, finally, to the blood circulation.

Fig. 5. Renografin density gradient profile of dopamine. Vacuole isolation was performed as described in Fig. 4 with pectin-ase from Aspergillus niger in the cell digestion medium. Gradient fractions were analyzed for dopamine content as described in Fig. 1...

Fig. 6. Distribution of sanguin-arine, thebaine and Ot mannosi-dase on renografin density gradients after limited cell wall hydrolysis. Cell fractionation was carried out as described in Fig. 4 except pectinase was omitted from the digestion medium. The volume of fraction collected is reflected in the width of the bars in the graph. (A) San-guinarine and (B) thebaine content and (C) a-mannosidase activity were determined as described in Fig. 4. Data shown are from the same experiment. In the original protoplasts, the concentrations of sanguinarine and thebaine were 11.6 and 0.013 Mg mg protein, respectively...

In attached growth film) methods, as with aerobic digestion, the microorganisms can be encouraged to grow attached to a support medium such as plastic packing or sand. In anaerobic digestion, the bed is usually fluidized rather than a fixed-bed... 

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