Activity measurements, use

Procedures of the beta-galactosidase activity measuring using colour reaction with ONPG and X-Gal without cells permeabilization were developed and the detection limit at the level of 4 ppb has been achieved. The influence of the foreign ions (phosphate, sulphate, carbonate et. al) was studied. 

F. Lisdat, B. Ge, E. Ehrentreich-Forster, R. Reszka, and F.W. Scheller, Superoxide dismutase activity measurement using cytochrome c-modified electrode. Anal. Chem. 71,1359—1365 (1999). 

Toxi-Chromotest is a commercial toxicity assay that is based on the assessment of the inhibition of (3-galactosidase activity, measured using a chromogenic substrate and a colorimeter. A mutant strain of Escherichia coli is revitalized from a lyophilized state prior to the test [39]. The principle of the MetSoil test is similar to that of the Toxi-Chromotest . 

The injected volume corresponding to one bolus is usually quite small, equivalent at the best to the void volume of the column. The principal advantage of the repeated bolus method is that small injection volumes are required. On the other hand, perfused activity measurements using small volumes requires high activity generators. 

The SOD activity measurements using the xanthine-xanthine oxidase nitro blue tetrazolium (NBT) method [45] indicated that a concentration of 0.75 xM of [Mn(OBz)(H-3,5-/-Pr2pz)(L 1)] 1 and 0.8 iM of the related [Mn(OBz)(Ll)] 2 complex exert the same SOD activity as one unit of native SOD. The high SOD activity of the tris(pyrazolyl)borate complexes was attributed to their structural similarities to the MnSOD active site [45],... 

Haemolytic activity was observed in samples during Phaeocystis pouchetii blooms in mesocosms. The activity measured using incubations of whole mesocosm samples mixed with blood suspensions was proportional with the amount of sample added. The haemolytic activity in the mesocosms correlated best with the density of non-motile P. pouchetii but also with the abundance of the larger phototrophs and heterotrophs. The last two were also positively related to P. pouchetii numbers. Biomass during the P. pouchetii bloom was dominated by non-motile P. pouchetii cells and... 

There is the following relation between activity A (Bq) and net count rate n (s ) in the case of activity measurement using the GM counter... 

Kim MJ, Nafzinger AN, Kashuba AD, Kirchheiner J, Bauer S, Gaedigk A, Bertino JS. Effects of fluvastatin and cigarette smoking on CYP2C9 activity measured using the probe S-warfarin. Eur J Clin Pharmacol 62, 431-6. 

Activity measurements using radiation other than electromagnetic have been performed in only a few cases only photon spectrometry is discussed here. 

Although the ionic activities measured using ion microelectrodes are accurate, the intracellular ions are largely bound except for a small space with which they and the cell membrane are in equilibrium. It is into this space that the ion electrodes are inserted. This argument arises from the observation of Carpenter, Hovey, and Bak (1971) that the intracellular conductance of Aply-sia nerve cell bodies is 10% that of sea water. They attribute this to a structuring of water which restricts the ability of the ions to carry electrical current. If this were the case it is difficult to explain the finding that multiple impalements of the same neuron with ion selective microelectrodes yield similar results. ... 

The best results for the dendritic compounds were obtained with a heterodimeric prodrug. Toxicity for prodrug 36, constructed of DOX and CPT, was about 50-fold higher than the activity measured using a combination of two monomeric prodrugs (34a and 35a) when bioactivation was performed. 

These CCMPs were not stable without crosslinking to maintain the active conformation. RNase was modified with HMPA as described above and derivatized with each of the eight commercially available aliphatic di-iffiidoesters. The activities measured using both DFP and PMSF are shown in Figure 1. 

From DSC and activity measurements using glucosidase (GOD), approximately the same results have been obtained (see Fig. 3) [18]. Komori et al. measured die residual activity of the microencapsulated GOD from A. niger in polyurea by interfacial polymerization after keeping the sample at a specified temperature for 10 min. They reported that the thermal stability of GOD was improved by fixation in a capsule [19]. Despite the difierence in the heat treatment method, the trend of the data is the same and the results on the free enzyme were nearly the same (see Fig. 3). Glucosidase fixim A. niger is a protein that contains about 16% saccharide chain [20]. Similar to invertase, it is possibly stabilized by interaction of the PVA-saccharide chain-water. 

Methods. Lipolytic activity measurements using tri- C-oleoylglycerol and methylumbelliferyl esters in enzyme assays, or by measurement of total lipid and free fatty acid (FFA) levels were as described recently Oxygen uptake by aqueous suspensions of wholemeal, bran, etc. correlates very closely (r 0.96 P < 0.001) with FFA content and has been used as a rapid and simple routine method for measuring deterioration of such materials during storage... 

T-labelled compounds (4T-n-heptane, etc.). ) Analysis of T-labelled products. ) Specific activity measurements. ) Use of T-labelled compounds. ... 

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