scholarly journals FACTORS INVOLVED IN THE USE OF ORGANIC SOLVENTS AS PRECIPITATING AND DRYING AGENTS OF IMMUNE SERA

1932 ◽  
Vol 16 (2) ◽  
pp. 243-256 ◽  
Author(s):  
Malcolm H. Merrill ◽  
Moyer S. Fleisher

1. In concentrations of 70 to 75 per cent the organic solvents methyl, ethyl, and propyl alcohols, and acetone cause complete precipitation of serum proteins and produce maximum loss in solubility. We have referred to this concentration range as the critical concentration. 2. As the concentration of the solvents is increased from about 75 per cent precipitation continues complete but loss in solubility progressively decreases until at all concentrations above about 87 per cent the precipitates formed at room temperature are completely soluble. 3. The degree of resolubility of the precipitates formed even in these high concentrations of the organic solvent decreases as the temperature is raised and as the duration of exposure is increased. 4. At 5°C. the precipitates formed in all concentrations of these organic solvents are completely resoluble. Also these solvents exert maximum precipitating effect at lower temperature. 5. Maximum precipitating effect by these organic solvents occurs at about pH 6.0 precipitation becoming progressively less as the pH value is altered either way from this point. 6. The more concentrated the serum, the greater the proportion of protein present that will be precipitated by any given concentrations of organic solvent. 7. A method for preparing dry immune sera has been given. Such dried sera have been extracted with a number of organic compounds without loss in solubility or antibody activity.

2011 ◽  
Vol 308-310 ◽  
pp. 436-441
Author(s):  
Zheng Yu Zhang ◽  
Hong Xu ◽  
Chun Ling Zheng

Cationic dye is a special dye for polyacrylonitrile, but it is very difficult in dying through the core. In practice, the price of special leveling agent for polyacrylonitrile fiber is high, and uniform staining is poor. By mixing a number of organic solvents in the dye bath, we can improve the structure of fibers and its deep-dyed. In this paper, we use n-propanol, isopropanol and benzyl alcohol as organic solvent, by adjusting the pH value and the appropriate temperature, and with special depth and leveling agent for dyeing soaping fastness contrast, to find economically viable process conditions.


Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 722
Author(s):  
Shuji Yomo

In this study, a 2-pack isocyanate curing waterborne paint (without organic solvents) encapsulating dibutyltin dilaurate (hereinafter, DBTL) in nonionic surfactant micelles with an hydrophilic–lipophilic balance of 13–14 in advance releases DBTL when the micelles are collapsed at 80 °C or higher, whereby the curing progresses rapidly. On the other hand, the viscosity levels of the paint before and after being left at 40 °C for 1 h are almost the same. Organic solvents are mandatory for waterborne paints to provide paint and film properties, but they might collapse the micelles when they are formulated in the paint. In this study, we investigate whether the abovementioned paint containing organic solvents can develop switching functionality in terms of maintaining the storage stability at 40 °C and expressing a catalytic function at 80 °C to progress the curing. As a result, we find that if the solubility of the organic solvent in water at 20 °C is at least 10 g/100 mL and the boiling point is ≤200 °C, both curing and storage stability can be achieved.


1957 ◽  
Vol 24 (2) ◽  
pp. 235-241 ◽  
Author(s):  
P. S. Robertson

Some of the factors influencing the concentration of carbon dioxide found in New Zealand Cheddar cheese have been investigated.1. Cheeses made with the use of commercial starters (containing betacocci) are characterized by a rapid increase in their carbon dioxide content during the 2 weeks following manufacture.2. Cheeses made with the use of single strain starters do not change in carbon dioxide content in the first 2 weeks following manufacture, but may ultimately contain as much carbon dioxide as commercial starter cheeses.3. High concentrations of carbon dioxide within a cheese result in an open texture, especially when the carbon dioxide is formed shortly after manufacture.4. The loss of carbon dioxide to the atmosphere is demonstrated by the existence of a carbon dioxide concentration gradient within the cheese.5. Storage of cheese at a lower temperature than is usual results in retarded carbon dioxide formation.


1981 ◽  
Vol 59 (19) ◽  
pp. 2921-2925 ◽  
Author(s):  
J. Bryan Jones ◽  
Diana H. Pliura

The esterolytic activity of native chymotrypsin (CT) immobilized on ionically neutral porous glass beads has been studied in the presence of up to 20% (v/v) of the organic solvents methanol, ethanol, 2-propanol, tert-butyl alcohol, dioxane, and DMSO. In marked contrast to the variations observed with native CT, inhibition of CT immobilized on glass (CT–glass) was independent of the nature of the organic solvent. The overall activity, as indicated by kc(app)/km(app), decreased by 35–50% as the concentration of all solvents surveyed was increased up to 20%. In general, high organic solvent concentration accelerated the rate of protein release from the insoluble catalyst. For practical applications in aqueous organic solvents CT–glass conjugates are inferior to those of the enzyme attached to Sephadex.


2020 ◽  
Vol 24 (3 Part A) ◽  
pp. 1785-1793
Author(s):  
Dongli Ma ◽  
Yuanyuan Chen ◽  
Yong Lai ◽  
Zanpei Zhang ◽  
Ximei Li ◽  
...  

Nerium indicum is an ornamental plant that is widely distributed in tropical and subtropical regions wordwide. It has toxic and medicinal properties which is closely related to the bioactive ingredients contained in Nerium indicum. In our research, the leaves of Nerium indicum was used as raw materials to study the chemical constituents and their effects. The chemical constituents of the leaves were analyzed by FT-IR and GC-MS with alcohol, benzene and acetone as organic solvents. A total of 73 compounds were obtained by acetone organic solvent, 25 compounds were extracted from benzene and 146 compounds were obtained from alcohol. Rich bioactive and bioenergy components were found in all three kinds of extract, suggesting that Nerium indicum leaves are of great significance for the diverse resourcing of bio-utilization including biomedicine, bioenergy, aroma, food additives.


2019 ◽  
Vol 57 (2) ◽  
pp. 28-34
Author(s):  
Lilia I. Mukhamedyarova ◽  
◽  
Sergey G. Bezryadin ◽  
Elena Yu. Klukvina ◽  
Vladimir V. Chevela ◽  
...  

The system of zirconium (IV) – dl-tartaric acid for metal: ligand 1: 1, 1: 2 and 1: 3 ratios in aqueous solution has been studied by means of using potentiometric titration method in combination with mathematical modeling. The comparison of Bjerrum functions from pH for zirconium(IV) systems: d-tartaric acid and zirconium (IV): dl-tartaric acid, has revealed the following features in the behavior of the curves: the degree of titration for the complexes at a fixed pH value for systems with dl-tartaric acid is more than for d-acid. The CPESSP software complex has calculated the composition, stability constants and molar fractions of zirconium(IV) tartrate accumulation. It has been also found that at a ratio of 1: 1 for Zr (IV) and ligand (H4Tart) ions in the system under study ZrHTart+ is formed, which is tetramerized into Zr4Tart40 and, further, tetranuclear particles of varying degrees of deprotonization are formed, as well as mononuclear forms. In a strongly alkaline pH environment > 10, Bjerrum curves for d- and dl-tartaric acids overlap each other and correspond to hydroxocomplexes of varying degrees of titration. For the 1: 2 ratio, the composition of the complexes for the zirconium(IV) – dl-H4T system is slightly different; compared to the zirconium(IV) – dH4T system, differences are clearly observed for both low and high concentrations. Based on these data, a complex formation scheme in the Zr(IV) – dl-tartaric acid system has been proposed for all the ratios studied. The characteristics of stereoselective diastereomer formation have been calculated. It has been revealed that in the medium of racemic tartrate, ddd- and lll-Zr(H2Tart)2(HTart)3-forms, as well as Zr(H2Tart)(НTart)24-Zr(HTart)35- are formed on a stereoselective basis.


1999 ◽  
Vol 65 (6) ◽  
pp. 2631-2635 ◽  
Author(s):  
Sonja Isken ◽  
Antoine Derks ◽  
Petra F. G. Wolffs ◽  
Jan A. M. de Bont

ABSTRACT Solvent-tolerant microorganisms are useful in biotransformations with whole cells in two-phase solvent-water systems. The results presented here describe the effects that organic solvents have on the growth of these organisms. The maximal growth rate of Pseudomonas putida S12, 0.8 h−1, was not affected by toluene in batch cultures, but in chemostat cultures the solvent decreased the maximal growth rate by nearly 50%. Toluene, ethylbenzene, propylbenzene, xylene, hexane, and cyclohexane reduced the biomass yield, and this effect depended on the concentration of the solvent in the bacterial membrane and not on its chemical structure. The dose response to solvents in terms of yield was linear up to an approximately 200 mM concentration of solvent in the bacterial membrane, both in the wild type and in a mutant lacking an active efflux system for toluene. Above this critical concentration the yield of the wild type remained constant at 0.2 g of protein/g of glucose with increasing concentrations of toluene. The reduction of the yield in the presence of solvents is due to a maintenance higher by a factor of three or four as well as to a decrease of the maximum growth yield by 33%. Therefore, energy-consuming adaptation processes as well as the uncoupling effect of the solvents reduce the yield of the tolerant cells.


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