scholarly journals ACTION OF FORMALDEHYDE ON ENZYMES AND ON CERTAIN PBOTEIDS

1899 ◽  
Vol 4 (1) ◽  
pp. 47-80 ◽  
Author(s):  
C. L. Bliss ◽  
F. G. Novy
Keyword(s):  
Room Temperature ◽  
Dilute Solution ◽  
Cent Solution ◽  
Dilute Solutions ◽  
Moderate Amount ◽  
Strong Concentration ◽  
Preceding Work ◽  
Micro Organisms ◽  
Short Time ◽  
Sufficient Concentration

The following general conclusions may be drawn from the preceding work: Fibrin is altered by formaldehyde and is then less easily digested by pepsin and by trypsin. Papaïn is apparently unable to digest fibrin even when this is exposed to very weak formaldehyde (1:1000) for a very short time. The casein of milk, on contact with formaldehyde, undergoes rapid alteration and is as a result not coagulated by rennet, or but very slowly. Such altered casein, like similar fibrin, is not readily digested by the proteolytic ferments. The longer the formaldehyde acts on casein and on fibrin the more marked is the result. Pepsin is not affected by a one per cent solution of formaldehyde, even when the mixture has stood for four weeks. Even a five per cent solution of formaldehyde acting for three weeks has no effect on pepsin. Contrary results obtained by others are due to an alteration of the fibrin by the formaldehyde. A putrid solution of pepsin in distilled water one month old digests fibrin as readily as a fresh solution. Rennet is not affected even by a four per cent solution of formaldehyde acting for several weeks. The absence of coagulation at times is due to the action of formaldehyde on the casein of the milk and not on the rennet ferment. Papaïn is very quickly altered by formaldehyde, even in very dilute solution. Moreover, it is unable to digest fibrin that has been exposed to the action of a very dilute solution of formaldehyde for a short time. Trypsin is altered by formaldehyde to such an extent that digestion of fibrin will not take place, or but very slowly. The extent to which trypsin is affected by formaldehyde depends largely upon the amount of organic matter present, as well as on the amount of ferment in the solution. Amylopsin is not destroyed by very dilute solutions of formaldehyde, but stronger solutions decrease the activity of the ferment, and if used in sufficient concentration will destroy it completely. Ptyalin, like the diastatic ferment of the pancreas, is not destroyed by dilute solutions of formaldehyde. If the latter is used in rather strong concentration and allowed to act for some time it will destroy the ferment. The action of formaldehyde is more rapid and more marked at a slightly elevated temperature than at ordinary room temperature. Malt diastase, unlike the diastatic ferments of the saliva and pancreatic solution, is not destroyed by formaldehyde when this is used in moderate amount and at ordinary temperature. Unlike pepsin, a solution of malt diastase readily undergoes decomposition on standing even for one or more days. This destruction is undoubtedly due to bacteria since it does not take place when formaldehyde is present. Consequently the favoring action which formaldehyde apparently exerts on diastase really consists in the inhibition of the growth of micro-organisms, and hence the diastase is protected against decomposition.

Knoevenagel Condensations Catalyzed by New Oil Shale Recyclable Catalyst at Room Temperature and Assisted by Ultrasounds Irradiations

2021 ◽  
Vol 37 (6) ◽  
pp. 1295-1301
Author(s):  
Elmustapha Ennesyry ◽  
Fathallaah Bazi ◽  
Bahija Mounir ◽  
M’hammed Elkouali Elkouali ◽  
Hassan Hannache ◽  
...  
Keyword(s):  
Heterogeneous Catalyst ◽  
Catalytic System ◽  
Oil Shale ◽  
Room Temperature ◽  
Knoevenagel Condensation ◽  
Recyclable Catalyst ◽  
Short Time

Functionalized alkenes were successfully synthesized via a clean procedure in a short time by using a new recycled heterogeneous catalyst prepared from Moroccan oil shale, this catalyst is characterized by different technics such XRD, BET-BJH, MEB-EDS, and TGA, before it’s has been used in the Knoevenagel condensation between different aldehydes and active methylenes. The results showed that coupling the catalyst with ultrasound irradiations could improve the catalytic system in this transformation by achieving the products in a very short time, the results showed clearly that this catalyst could be considered as excellent recyclable support in Knoevenagel condensation.

The use of methyl green as a histochemical reagent

1965 ◽  
Vol s3-106 (73) ◽  
pp. 3-13
Author(s):  
JOHN R. BAKER ◽  
ELIZABETH G. M. WILLIAMS
Keyword(s):  
Connective Tissue ◽  
Malachite Green ◽  
Helix Aspersa ◽  
Common Snail ◽  
Methyl Green ◽  
Dilute Solution ◽  
Dilute Solutions ◽  
The Common ◽  
Snail Helix Aspersa

The cation of methyl green carriea two poaitive charges, that of malachite green only one; but the two dyes behave towards tissue-constituents in almost exactly the same way. These dyes are not specific for chromatin. They colour certain objects that are devoid of DNA, even when they are used in very dilute solution. The granules of cells called Körnchenzellen in the connective tissue of the common snail, Helix aspersa, are strongly coloured by both dyes from very dilute solutions, and thus provide a striking instance of the unspecificity of these dyes. Malachite green, which is stable and free from contamination by metachromstic impurities, can advantageously replace the methyl green commonly used in mixtures with pyronine. It is suggested that pyronine may have a greater capacity for penetrating into close-textured objects, such ss nucleoli and ribosomes, than methyl and malachite greens.

scholarly journals Growth of Micro-organisms in Two Propofol Products at Room Temperature

2005 ◽  
Vol 25 (2) ◽  
pp. 154-161
Author(s):  
Michiaki YAMAKAGE ◽  
Hiroki YAMAMOTO ◽  
Akiyoshi NAMIKI
Keyword(s):  
Room Temperature ◽  
Micro Organisms

scholarly journals Effect of Roasting and Brewing on the Antioxidant and Antiproliferative Activities of Tartary Buckwheat

Foods ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1331
Author(s):  
Ji-yeon Ryu ◽  
Yoonseong Choi ◽  
Kun-Hwa Hong ◽  
Yong Suk Chung ◽  
Somi Kim Cho
Keyword(s):  
Breast Cancer Cells ◽  
Room Temperature ◽  
Tartary Buckwheat ◽  
Flavonoid Content ◽  
Total Polyphenol ◽  
Antiproliferative Effects ◽  
Long Time ◽  
Short Time ◽  
Antiproliferative Activities

We evaluated the effect of the roasting and brewing conditions of Tartary buckwheat (TB), which is widely used in infusion teas, on its antioxidant and antiproliferative activities in vitro. TB was roasted at 210 °C for 10 min and brewed at a high temperature for a short time (HTST; 85–90 °C, 3 min) or at room temperature for a long time (RTLT; 25–30 °C, 24 h). Roasted TB (RTB) tea brewed at RTLT had the highest total polyphenol content (TPC) and total flavonoid content (TFC) among the four TB teas for different roasting and brewing conditions. Moreover, RTB brewed at RTLT showed the greatest 2,2-diphenyl-1-picrylhydrazyl-, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)-, and alkyl-scavenging activities. The TB tea brewed at RTLT had higher Fe2+-chelating activity than that brewed at HTST, irrespective of roasting. Moreover, RTB tea brewed at RTLT inhibited the proliferation of human pancreatic and breast cancer cells. Overall, RTB-RTLT displayed the largest effect on antioxidant and antiproliferative effects. Finally, rutin was found to possess the most pronounced effect on the antioxidant and antiproliferative activities of the TB teas. These results indicate that the antioxidant and antiproliferative activities of RTB are enhanced by RTLT brewing.

Metal-free phosphonation of heteroarene N-oxides with trialkyl phosphite at room temperature

2017 ◽  
Vol 15 (15) ◽  
pp. 3165-3169 ◽  
Author(s):  
Ming-Tao Chen ◽  
Xia You ◽  
Li-Gang Bai ◽  
Qun-Li Luo
Keyword(s):  
Room Temperature ◽  
Trialkyl Phosphite ◽  
Metal Free ◽  
Mild Conditions ◽  
Short Time

Heteroarene N-oxides were successfully converted to heteroarylphosphonates in a very short time under mild conditions through in situ activation with CBrCl3.

Susceptibility of Chromium?Based Alloys of Transition Elements

1960 ◽  
Vol 13 (2) ◽  
pp. 451 ◽  
Author(s):  
WM Lomer
Keyword(s):  
Magnetic Properties ◽  
Transition Metals ◽  
Specific Heat ◽  
Room Temperature ◽  
Spin Moment ◽  
Transition Elements ◽  
Dilute Solutions ◽  
Spin Orientation ◽  
Local Moments ◽  
The Matrix

The magnetic properties of chromium�based alloys with the transition metals are very varied. Below room temperature it is believed that chromium is antiferrcmagnetic and in this paper we investigate briefly the nature of the influence of this antiferrcmagnetic matrix on the properties of dilute solutions of atoms carrying weIl�defined local moments of their own. It is shown that various anomalies in the susceptibility-temperature relations can be rationalized in terms of a model involving small spin orientation forces arising from the antiferromagnetism. Alloying with vanadium appears to reduce the spin moment on the chromium atoms, but to introduce no localized spins itself. The temperature.independent contribution of cobalt in solution is interpreted in terms of local spins locked by the antiferromagnetism of the matrix. The :results so far obtained suggest that careful specific heat measurements in the range 0--100 OK may disclose very significant anomalies in many of. these alloys.

scholarly journals Mycobacterium tuberculosis Chaperonin 10 Is Secreted in the Macrophage Phagosome: Is Secretion Due to Dissociation and Adoption of a Partially Helical Structure at the Membrane?

2003 ◽  
Vol 185 (14) ◽  
pp. 4256-4267 ◽  
Author(s):  
Gianluca Fossati ◽  
Gaetano Izzo ◽  
Emanuele Rizzi ◽  
Emanuela Gancia ◽  
Daniela Modena ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Organic Solvent ◽  
Room Temperature ◽  
Helical Structure ◽  
Bound State ◽  
Solvent Mixtures ◽  
Dilute Solutions ◽  
Chaperonin 10 ◽  
Β Sheet ◽  
Mycobacterial Protein

ABSTRACT To confirm that Mycobacterium tuberculosis chaperonin 10 (Cpn10) is secreted outside the live bacillus, infected macrophages were examined by electron microscopy. This revealed that the mycobacterial protein accumulates both in the wall of the bacterium and in the matrix of the phagosomes in which ingested mycobacteria survive within infected macrophages. To understand the structural implications underlying this secretion, a structural study of M. tuberculosis Cpn10 was performed under conditions that are generally believed to mimic the membrane environment. It was found that in buffer-organic solvent mixtures, the mycobacterial protein forms two main species, namely, a partially helical monomer that prevails in dilute solutions at room temperature and a dimer that folds into a β-sheet-dominated structure and prevails in either concentrated protein solutions at room temperature or in dilute solutions at low temperature. A partially helical monomer was also found and was completely associated with negatively charged detergents in a micelle-bound state. Remarkably, zwitterionic lipids had no effect on the protein structure. By using N- and C-truncated forms of the protein, the C- and N-terminal sequences were identified as possessing an amphiphilic helical character and as selectively associating with acidic detergent micelles. When the study was extended to other chaperonins, it was found that human Cpn10 is also monomeric and partially helical in dilute organic solvent-buffer mixtures. In contrast, Escherichia coli Cpn10 is mostly dimeric and predominately β-sheet in both dilute and concentrated solutions. Interestingly, human Cpn10 also crosses biological membranes, whereas the E. coli homologue is strictly cytosolic. These results suggest that dissociation to partially helical monomers and interaction with acidic lipids may be two important steps in the mechanism of secretion of M. tuberculosis Cpn10 to the external environment.

The Influence of Test Temperature on the Ratchetting Behavior of Type 304 Stainless Steel

1989 ◽  
Vol 111 (4) ◽  
pp. 378-383 ◽  
Author(s):  
M. B. Ruggles ◽  
E. Krempl
Keyword(s):  
Stress Level ◽  
Driving Force ◽  
Room Temperature ◽  
Maximum Stress ◽  
Elevated Temperatures ◽  
304 Stainless Steel ◽  
Short Time ◽  
Independent Behavior ◽  
Type 304 ◽  
Type 304 Stainless Steel

The zero-to-tension ratchetting behavior was investigated under uniaxial loading at room temperature and at 550, 600, and 650°C. In History I the maximum stress level of ratchetting was equal to the stress reached in a tensile test at one percent strain. For History II the maximum stress level was established as the stress reached after a 2100 s relaxation at one percent strain. Significant ratchetting was observed for History I at room temperature but not at the elevated temperatures. The accumulated ratchet strain increases with decreasing stress rate. Independent of the stress rates used insignificant ratchet strain was observed at room temperature for History II. This observation is explained in the context of the viscoplasticity theory based on overstress by the exhaustion of the viscous contribution to the stress during relaxation. The viscous part of the stress is the driving force for the ratchetting in History I. Strain aging is presumably responsible for the lack of short-time inelastic deformation resulting in a nearly rate-independent behavior at the elevated temperatures.

Isoprene and Rubber. XIX. The Molecular Size of Rubber and Balata

1930 ◽  
Vol 3 (3) ◽  
pp. 519-521 ◽  
Author(s):  
H. Staudinger ◽  
H. F. Bondy
Keyword(s):  
Molecular Weight ◽  
Organic Solvent ◽  
Average Molecular Weight ◽  
Molecular Size ◽  
Dilute Solution ◽  
Decomposition Products ◽  
Viscosity Measurements ◽  
Gutta Percha ◽  
Preceding Work

Abstract It was shown in the preceding work that a very dilute solution of balata in an organic solvent contains macromolecules in solution and not micelles. The same is true of rubber. On the basis of these findings it is possible to calculate the molecular weight of rubber and balata from viscosity measurements by means of the formula developed in a previous work: M=η8p/c. Km. The supposition is made that the molecules of rubber and balata have the form of threads and double threads, respectively. Also it is necessary to determine the constant KKm, and this may be calculated in the case of low molecular products, where the average molecular weight can be determined as well as the viscosity of the solutions. Such semi-colloidal decomposition products were obtained by heating rubber or gutta-percha in either tetralin or xylene. As shown by the following table the four samples thus obtained gave the constant: 0.3×10−3,5

Misting-free diamond surface created by sheet electron beam irradiation

2001 ◽  
Vol 16 (2) ◽  
pp. 553-557 ◽  
Author(s):  
Kazuya Oguri ◽  
Nobuhiro Iwataka ◽  
Akira Tonegawa ◽  
Yoichi Hirose ◽  
Kazuo Takayama ◽  
...  
Keyword(s):  
Electron Beam ◽  
Size Distribution ◽  
Room Temperature ◽  
Electron Beam Irradiation ◽  
Diamond Surface ◽  
Beam Irradiation ◽  
Duration Time ◽  
Clear Vision ◽  
Sheet Electron Beam ◽  
Short Time

We developed a diamond surface that does not mist near the room temperature under a saturated humidity atmosphere, by sheet electron beam irradiation (SEBI) treatment. SEBI treatment decreased the time to clear vision of the diamond surface. Following SEBI treatment for 1.91 s (= 0.72 MGy) to a diamond surface, the time to clear vision was less than 2 s. The effective duration time was a few hours. Based on the results of the size distribution of the drops on the misting-free diamond surface following blowing for 3 s, we proposed an explanation for the short time to clear vision of the diamond surface treated by SEBI.

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