Endogenous Enzyme Activity and Seafood Quality: Influence of Chilling, Freezing, and Other Environmental Factors

2000 ◽  
pp. 477-514
Keyword(s):  
Enzyme Activity ◽  
Environmental Factors

scholarly journals EFFECT ON 6-BAP CATALASE ACTIVITY IN TOMATO PLANTS UNDER CONDITIONS OF TEMPERATURE STRESS

2015 ◽  
Vol 4 (2) ◽  
pp. 96-99
Author(s):  
Tatyana Stepanovna Kolmykova ◽  
Ekaterina Vladimirovna Klokova ◽  
Elvera Shagidulovna Sharkaeva
Keyword(s):  
Enzyme Activity ◽  
Antioxidant Enzymes ◽  
Environmental Factors ◽  
Catalase Activity ◽  
Low Temperatures ◽  
High Ability ◽  
Tomato Plants ◽  
Resistance To Stress ◽  
Primary Antioxidant ◽  
A Minor

Activity of the antioxidant system is one of the mechanisms for the protection of plants against adverse environmental factors. Catalase - a primary antioxidant enzymes. Her change may serve as an indicator of plant resistance to stress. Studied catalase activity in tomato plants of different varieties under the action of low temperatures and cytokinin 6-BAP preparation. The object of investigation used 24- and 27-day-old tomato plant varieties Podarochnyi, Patrice, Volgogradskyi. Found that under the action of low temperatures, the decrease in positive catalase activity: 10-30% at 10 C and 40-60% at a temperature of 3 C as compared with non-refrigerated plants. Less resistant to hyperthermia were plant varieties Patrice. With increasing length of vegetation at a temperature of 25 C in 27-day-old tomato plants resulted in a minor increase in the activity of the enzyme. After the end of the cooling observed recovery of enzyme activity only at grades Podarochnyi and Patrice. This indicates that the indicated tomato varieties possess a high ability to restore metabolic processes. Using 6-regulator cytokinin BAP increased catalase activity in tomato plants as prolonged or momentary cooling. Especially responsive to the drug were plant varieties Patrice and Volgogradskyi. And 6-BAP helped repair catalase activity in 27-day-old plants in the aftereffect of cold stress. Were more sensitive plant varieties Podarochnyi.

Responses of the phosphatase activity of the lichen Cladina rangiferina to various environmental factors including metals

1979 ◽  
Vol 57 (14) ◽  
pp. 1534-1540 ◽  
Author(s):  
I. Lane ◽  
K. J. Puckett
Keyword(s):  
Enzyme Activity ◽  
Environmental Factors ◽  
Phosphatase Activity ◽  
Enzyme Activities ◽  
Enzyme Concentration ◽  
Acidic Ph ◽  
Nitrophenyl Phosphate ◽  
Cladina Rangiferina ◽  
Reduced Activity ◽  
Menten Constant

The characteristics of phosphatase activity of Cladina rangiferina (L.) Harm, have been studied. Calculations of enzyme activities were based on the liberation of p-nitrophenol from p-nitrophenyl phosphate. The phosphatase activity was found to be linear both with increasing sample size (enzyme concentration) and increasing time, showed highest activity at acidic pH, and had a Michaelis–Menten constant of 8.9 × 10−3 M. The enzyme activity was maximal in the range 61 ± 10 °C, was independent of light, and was completely eliminated by boiling the thalli. Various cations and anions were tested for their effect; uranyl and vanadyl ions inhibited activity by 60% whereas copper, nickel, and silver enhanced activity by 10%. The anions biselenite, cyanide, fluoride, molybdate, phosphate, and vanadate all greatly reduced activity (≥ 50%). Phosphatase activity was demonstrated in other lichen species.

scholarly journals Dynamics of physiologically active cells of pico- and nanophytoplankton in the coastal waters of Black Sea

2016 ◽  
Author(s):  
Ekaterina Solomonova
Keyword(s):  
Flow Cytometry ◽  
Enzyme Activity ◽  
Environmental Factors ◽  
Black Sea ◽  
Coastal Waters ◽  
Seasonal Changes ◽  
Warm Season ◽  
Study Groups ◽  
Living Cells ◽  
Intracellular Enzyme

The dynamics of the abundance and viability index (VI) of pico- and nanophytoplankton in the coastal waters of Black Sea near Sevastopol were investigated by regular monthly monitoring using flow cytometry and fluorescein diacetate vital dye (FDA), as a marker of intracellular enzyme activity. Directed seasonal changes in the fraction of physiologically active cells in the study groups of algae in coastal waters was not identified. It is noted that, in the warm season and during vegetative growth of algae in the composition and pico nano-phytoplankton predominate living cells, the percentage of which varies from 70 to 100 %. Low values of the VI (30 %) picophytoplankton were obtained at individual stations in September, October and December, possibly due to the presence of this kind of cell size group Synechococcus, which are very sensitive to fluctuations of environmental factors. Refs 28. Figs 7.

Studies of the Nutritional, Environmental Effects and Repressive Nature of Simple Sugars on the Production of endo-β-mannanase by Aspergillus flavus PT7 on Solid State Fermentation

2019 ◽  
pp. 1-12
Author(s):  
Ukponobong E. Anita ◽  
Nsikak U. Stephen ◽  
Abiodun A. Onilude ◽  
Inimfon A. Ibanga
Keyword(s):  
Enzyme Activity ◽  
Environmental Factors ◽  
Aspergillus Flavus ◽  
Nitrogen Sources ◽  
Growth Conditions ◽  
Inoculum Size ◽  
Lag Period ◽  
Production Increase ◽  
Set Up ◽  
Ibadan Nigeria

Aims: The importance of nutritional and environmental factors in the production of microbial enzymes cannot be overemphasized. Hence, endo-β-mannanase production was systematically studied in a step-wise approach of building up on the experimentally observed conditions favouring the production of this enzyme in Aspergillus flavus PT7. Place and Duration of Study: Department of Microbiology, University of Ibadan, Nigeria, between January 2018 and December 2018. Methodology: Thirty-eight (38) fungal isolates obtained were screened for mannolytic ability using standard method. The highest producer of endo-β-mannasase was subjected to various production conditions by adjusting the nutritional and environmental factors in view of optimizing the production of this enzyme in the isolate Aspergillus flavus PT7. Results: Copra meal was the highest inducer of mannanase production in the isolate at enzyme activity of 85.86±3.93 U/gds. Production increased to 94.54±0.42 when all forms of extraneous nitrogen sources were excluded from the production medium. pH 5.0, temperature 30°C, moisture content at 100% v/w and inoculum size of 8.0% v/w led to the increase in production by 44% (enzyme activity of 153.24±5.69 U/gds) in 5 days of incubation. Allowing the production set up additional two (2) days led to production increase with a recorded enzyme activity of 170.34±4.35 U/gds. Production of endo-β-mannanase in A. flavus PT7 was observed to be inductive as the presence of simple sugars like glucose, galactose, arabinose and xylose led to extended lag period in the production of the enzymes by the isolate. Conclusion: Production of endo-β-mannanase by Aspergillus flavus PT7 was successfully optimized in a step-wise and systematic experimental study of the nutritional and environmental growth conditions of the isolate.

scholarly journals β-glucosidase PYK 10 gene expression in Arabidopsis thaliana (L.) Heynh. seedlings under clinorotation and X-radiation

2019 ◽  
Vol 25 ◽  
pp. 166-171
Author(s):  
S. M. Romanchuk
Keyword(s):  
Gene Expression ◽  
Arabidopsis Thaliana ◽  
Endoplasmic Reticulum ◽  
Enzyme Activity ◽  
Environmental Factors ◽  
Plant Protection ◽  
Plant Responses ◽  
Main Components ◽  
Spaceflight Experiments ◽  
Plant Protection System

Aim. Among plants used in spaceflight experiments, species of family Brassicaceae are considered as the most resistant to radiation exposure. It is supposed that ER-bodies, which are derivative of granular endoplasmic reticulum and selectively accumulate an enzyme β-glucosidase, may be responsible for this resistance. We firstly investigated expression of β-glucosidase PYK10 gene in A. thaliana seedlings under slow horizontal clinorotation and Х-radiation of doses 0.5 Gy, 1 Gy, 2 Gy, 4 Gy, 6 Gy, 8 Gy, 10 Gy, and 12 Gy. Methods. Seedlings were grown on agar nutrient medium. PYK 10 expression was determined using a method of real-time PCR. Results. Significant enhancement of PYK 10 expression and increasing a number of ER-bodies in A. thaliana seedlings under the influence of clinorotation and X-radiation in comparison with control was established. An increase in the number of ER-bodies was due to PYK 10 high expression and β-glucosidase synthesis without a rise of enzyme activity under clinorotation, while β-glucosidase activity increased under X-radiation. Plant responses to X-radiation became adaptive during 10 days after radiation, in which β-glucosidase plays a crucial role. Conclusions. Increased PYK 10 expression in A. thaliana seedlings under clinorotation and X-radiation is a part of the internal program of plant protection against the action of environmental factors. ER-bodies containing β-glucosidase may be one of the main components of the plant protection system from the influence of clinorotation and X-radiation. Keywords: Arabidopsis thaliana (L.) Heynh., ER-bodies, β-glucosidase, gene expression, clinorotation, Х-radiation.

scholarly journals Dynamics of activity of energy supply enzymes of rat brain against the background of exposure to stress factors

2019 ◽  
Vol 17 (1) ◽  
pp. 16-32
Author(s):  
A. M. Rashidova
Keyword(s):  
Enzyme Activity ◽  
Energy Metabolism ◽  
Environmental Factors ◽  
Energy Supply ◽  
The Body ◽  
Stress Factors ◽  
Functional Relations ◽  
Metabolism Enzymes ◽  
The Impact ◽  
The Brain

Aim. The aim of this work was to give a review of own studies of dynamics of the activity of energy metabolism enzymes in the brain during postnatal ontogenesis which characterizes the functional relations within the analysers, the destruction of their functions and the impact of adverse environmental factors on the body as well. Methods. The methods for the determination of the activity of energy metabolism enzymes in the brain of animals under the impact of adverse environmental factors and dysfunction of the analysers have been used. Results. It has been stated that the enzyme activity is regionally different in the tissues and sub cellular fractions of the brain depending on the animal species and the degree of the intensity of the stress factors, age and sex of the animal, circadian rhythms, season andmoreover, the resulting changes in the enzyme activity in most casesare irreversible. Conclusions. The data allow the dynamics of the activity of the energy supply enzymes to be considered as a determinant of cell reaction in response to exposure to adverse environmental factors and disturbance of sensory impulsation, which results in temporary increasing in the protection of intracellular energy metabolism through the development of an adaptive brain response.Key words: ontogenesis, brain, analysers, enzymes, environmental factors.

Reductionist thinking and animal models in neuropsychiatric research

2019 ◽  
Vol 42 ◽  
Author(s):  
Nicole M. Baran
Keyword(s):  
Animal Models ◽  
Mental Disorders ◽  
Environmental Factors ◽  
Neuropsychiatric Disorders ◽  
Model Organisms ◽  
Developmental Genetic ◽  
Term Study ◽  
Genetic And Environmental Factors ◽  
Mechanisms Of Plasticity

AbstractReductionist thinking in neuroscience is manifest in the widespread use of animal models of neuropsychiatric disorders. Broader investigations of diverse behaviors in non-model organisms and longer-term study of the mechanisms of plasticity will yield fundamental insights into the neurobiological, developmental, genetic, and environmental factors contributing to the “massively multifactorial system networks” which go awry in mental disorders.

Morphological and biochemical analyses of changes in rat hepatocytes related to wine and ethanol consumption

1984 ◽  
Vol 42 ◽  
pp. 232-233
Author(s):  
S.M. Geyer ◽  
C.L. Mendenhall ◽  
J.T. Hung ◽  
E.L. Cardell ◽  
R.L. Drake ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Enzyme Activity ◽  
Malic Enzyme ◽  
Smooth Endoplasmic Reticulum ◽  
Rat Hepatocytes ◽  
Mature Male ◽  
Treatment Groups ◽  
Malic Enzyme Activity ◽  
Biochemical Analyses

Thirty-three mature male Holtzman rats were randomly placed in 3 treatment groups: Controls (C); Ethanolics (E); and Wine drinkers (W). The animals were fed synthetic diets (Lieber type) with ethanol or wine substituted isocalorically for carbohydrates in the diet of E and W groups, respectively. W received a volume of wine which provided the same gram quantity of alcohol consumed by E. The animals were sacrificed by decapitation after 6 weeks and the livers processed for quantitative triglycerides (T3), proteins, malic enzyme activity (MEA), light microscopy (LM) and electron microscopy (EM). Morphometric analysis of randomly selected LM and EM micrographs was performed to determine organellar changes in centrilobular (CV) and periportal (PV) regions of the liver. This analysis (Table 1) showed that hepatocytes from E were larger than those in C and W groups. Smooth endoplasmic reticulum decreased in E and increased in W compared to C values.

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