scholarly journals Assessment of Propionibacterium Metabolic Activity on Protein Substrate of Sarcoplasmic Fraction in Hydrobionts’ Muscle Tissue

2020 ◽  
Author(s):  
Ekaterina Kramarenko ◽  
Elena Makarevich ◽  
Yana Bahareva ◽  
Daniil Makarevich ◽  
Anastasia Afanaseva
Keyword(s):  
Enzymatic Activity ◽  
Proteolytic Activity ◽  
Muscle Tissue ◽  
Metabolic Activity ◽  
Fish Muscle ◽  
Bacterial Suspension ◽  
Chemical Factors ◽  
Chemical Conditions ◽  
Tyrosine Concentration ◽  
Physical And Chemical

As a result of the conducted scientific researches, the authors analyzed methodical aspects of studying the proteolytic properties of Propionibacterium freudenreichii subsp. shermanii-KM 186 – the representatives of the probiotic group of microorganisms, which allowed not only to evaluate the enzymatic activity of the objects of study but also to discover how physical and chemical factors influence the proteins hydrolysis intensity in sarcoplasmic and myofibrillary fractions of hydrobionts’ muscle tissue. During the experiment which aimed at assessing the possibility of using individual protein fractions of fish muscle tissue as a substrate for proteolysis by Propionibacterium bacteria for the spectrophotometry analysis of their enzymatic activity, it was found that the sarcoplasmic fraction can be used as a substrate for studying the microorganisms’ proteolytic activity. Determination of the information content of tyrosine concentration measuring by spectrophotometry to characterize the proteolytic activity of bacterial suspensions showed that to assess the enzymatic activity of living microorganisms culture it is advisable to use not the absolute values of the bacterial suspension activity, expressed in μmolTYR/ml×min or the tyrosine concentration in the sample (μmol/L), but the change in the tyrosine level in comparison with its primary values. This way of expressing the results will allow us to assess the prevalence of processes (dissimilation/assimilation). In addition, the experiment revealed the characteristic response of the Propionibacterium bacteria’s metabolic activity to changes in the physical and chemical conditions.

Permeability to albumin in isolated coronary venules

1993 ◽  
Vol 265 (2) ◽  
pp. H543-H552 ◽  
Author(s):  
Y. Yuan ◽  
W. M. Chilian ◽  
H. J. Granger ◽  
D. C. Zawieja
Keyword(s):  
Permeability Coefficient ◽  
Filtration Rate ◽  
Intraluminal Pressure ◽  
Apparent Permeability ◽  
Filtration Pressure ◽  
Diffusive Permeability ◽  
Apparent Permeability Coefficient ◽  
Chemical Conditions ◽  
Physical And Chemical ◽  
Intravascular Pressure

This study reports measurements of albumin permeability in isolated coronary venules. The isolated microvessel technique allows the quantification of transmural exchange of macromolecules under tightly controlled physical and chemical conditions. Transvenular exchange of albumin was studied in isolated coronary venules during alterations in filtration rate caused by changes in intravascular pressure. The apparent permeability coefficient of albumin (Pa) at an intraluminal pressure of 11 cmH2O was 3.92 +/- 0.43 x 10(-6) cm/s. Elevating intraluminal pressure to 16 and 21 cmH2O increased Pa to 5.13 +/- 0.57 x 10(-6) and 6.78 +/- 0.66 x 10(-6) cm/s, respectively. Calculation of the true diffusive permeability coefficient of albumin (Pd) at zero filtration rate was 1.54 x 10(-6) cm/s. The product of hydraulic conductance (Lp) and (1 - sigma), where sigma is the solute reflection coefficient, was 3.25 x 10(-7) cm.s-1 x cmH2O-1. At a net filtration pressure of 4-5 cmH2O, diffusion accounts for > 60% of total albumin transport across the venular wall. Transmural albumin flux is very sensitive to filtration rate, rising 6.7% for each cmH2O elevation of net filtration pressure. At 11 cmH2O net filtration pressure, convection accounts for nearly 70% of net albumin extravasation from the venular lumen. We suggest that the isolated coronary venule is a suitable preparation for the study of solute exchange in the heart.

scholarly journals Origin of Life on Mars: Suitability and Opportunities

Life ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 539
Author(s):  
Benton C. Clark ◽  
Vera M. Kolb ◽  
Andrew Steele ◽  
Christopher H. House ◽  
Nina L. Lanza ◽  
...  
Keyword(s):  
Origin Of Life ◽  
Energy Sources ◽  
Early Earth ◽  
Sediment Samples ◽  
Life On Mars ◽  
Eventual Return ◽  
History Of ◽  
Early Mars ◽  
Chemical Conditions ◽  
Physical And Chemical

Although the habitability of early Mars is now well established, its suitability for conditions favorable to an independent origin of life (OoL) has been less certain. With continued exploration, evidence has mounted for a widespread diversity of physical and chemical conditions on Mars that mimic those variously hypothesized as settings in which life first arose on Earth. Mars has also provided water, energy sources, CHNOPS elements, critical catalytic transition metal elements, as well as B, Mg, Ca, Na and K, all of which are elements associated with life as we know it. With its highly favorable sulfur abundance and land/ocean ratio, early wet Mars remains a prime candidate for its own OoL, in many respects superior to Earth. The relatively well-preserved ancient surface of planet Mars helps inform the range of possible analogous conditions during the now-obliterated history of early Earth. Continued exploration of Mars also contributes to the understanding of the opportunities for settings enabling an OoL on exoplanets. Favoring geochemical sediment samples for eventual return to Earth will enhance assessments of the likelihood of a Martian OoL.

Further Studies upon Chemical Factors Affecting the Breeding of Anopheles in Trinidad

1934 ◽  
Vol 25 (4) ◽  
pp. 491-494 ◽  
Author(s):  
P. A. Buxton
Keyword(s):  
Analytical Study ◽  
Chemical Constituents ◽  
Physical Factors ◽  
Factors Affecting ◽  
Early Stages ◽  
Freshwater Biology ◽  
Chemical Technique ◽  
Chemical Factors ◽  
Physical And Chemical

During the last decade, entomologists have made progress in understanding the environment in which certain insects live; in particular, we begin to understand the effect of certain physical and chemical factors, which make up a part of the environment. With this gain in knowledge, it is sometimes possible to forecast outbreaks of insects and of diseases conveyed by them, and one can sometimes say that a particular alteration of the environment will result in loss or gain. But so far as mosquitos are concerned, one must admit that though much work has been devoted to the analytical study of the water in which the early stages are passed, the results are disappointing. A consideration of the published work suggests several reasons for this. Investigation into the ecology of the mosquito has had a vogue, and much of it has been done by workers who were isolated and whose knowledge of chemical technique and freshwater biology was limited. Apart from that, the inherent difficulties are great, for the worker must hunt for the limiting chemical and physical factors among a host of others which are doubtless unimportant, and there are few clues to indicate which of the chemical constituents of the water affects the mosquito. The data are therefore voluminous and it is difficult to reduce them to order and present them so that they can be readily understood.

Menadione nicotinamide bisulphite as a source of vitamin K and niacin activities for the growing pig

2000 ◽  
Vol 71 (1) ◽  
pp. 111-117 ◽  
Author(s):  
M. Marchetti ◽  
M. Tassinari ◽  
S. Marchetti
Keyword(s):  
Vitamin K ◽  
Control Diet ◽  
Live Weight ◽  
Organic Salt ◽  
Free Form ◽  
Food Supplementation ◽  
Sodium Bisulphite ◽  
Chemical Factors ◽  
And Control ◽  
Physical And Chemical

AbstractWhen compared with other menadione derivatives such as menadione sodium bisulphite (MSB), menadione nicotinamide bisulphite (MNB), an organic salt combining menadione and nicotinamide, shows better stability towards physical and chemical factors once it is added to pre-mixes or foods. The present work evaluates the bioavailability of the two vitamins present in this compound and toxicity in the pig. To assess vitamin bioavailability, pigs were given small amounts of food containing MNB or equivalent amounts of MSB and nicotinamide in the free form. Menadione and nicotinamide concentrations in blood samples drawn at set times after the diets were given did not reveal any significant differences between the two modes of administration. Haematic levels of both vitamins in animals receiving MNB, or MSB and nicotinamide, were after 2, 4, 8 and 12 h higher (P < 0·001) than those of untreated animals. The tolerance level to MNB was evaluated in pigs given diets containing graded amounts of MNB (100, 500, 2500 mg/kg) for 28 days. No significant (P > 0·05) differences were recorded in live weight, food intake and gain/food ratio in pigs given these diets when compared with those given an unsupplemented diet. Haemoglobin and bilirubin levels did not differ between animals given various amounts of MNB and control animals. Plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in pigs given 100 mg/kg of MNB did not show significant differences when compared with those observed in pigs given an unsupplemented control diet. In pigs on the diets supplemented with 500 and 2500 mg/kg of MNB there was a significant increase in the two enzymatic activities as compared with controls (P < 0·001 and P < 0·01). In the case of ALT this had disappeared by 28 weeks. MNB is a good source of vitamin K for the pig and does not appear to have any adverse effects, even when administered at levels higher than those normally used in pig food supplementation.

The Qualitative and Quantitative Distribution of Plankton in the Strait of Georgia in Relation to Certain Oceanographic Factors

1957 ◽  
Vol 14 (4) ◽  
pp. 521-552 ◽  
Author(s):  
Joseph Eugène Henri Légaré
Keyword(s):  
Salinity Gradient ◽  
General Distribution ◽  
Fraser River ◽  
Strait Of Georgia ◽  
Quantitative Distribution ◽  
Qualitative And Quantitative ◽  
Chemical Factors ◽  
Physical And Chemical ◽  
Plankton Communities ◽  
Made In

In order to gain some picture of the seasonal variations in the plankton communities two cruises were made in the Strait of Georgia, one in June 1955, and the other in November 1955; 165 plankton collections were taken, also surface temperatures.The correlation of these data have resulted in a number of conclusions concerning the distribution of plankton in the Strait of Georgia. The chief factor affecting the general distribution of plankton is the salinity gradient. The inflow of fresh water from the Fraser River forms zones of varying properties, and leads to the development of different plankton communities. The extent to which physical and chemical factors may determine the presence or absence of certain organisms from the zones described is discussed.

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