scholarly journals The Effect of High Temperature on α-Amylase Enzyme Activity in the Germination of Several Rice Varieties (Oryza sativa L.)

2021 ◽  
Vol 3 (2) ◽  
pp. 50-54
Author(s):  
Afrima Sari

High temperatures can affect plant morphophysiological changes and enzyme denaturation that can interfere with the germination process. This research aims to study the effect of temperature changes on the α-amylase enzyme activity of several rice varieties germination. The research applies Factorial Experiment in Completely Random Design, where the first factor is four levels of rice varieties, Anak Daro, Batang Piaman, Cisokan, and Inpari 30. The second factor is temperature level, 28 0C, 32 0C, 36 0C, 40 0C, 44 0C and 48 0C. Results showed that the activity of the α -amylase enzymes of the four varieties increased when the temperature increased to reach the optimal temperature, and denaturation began to occur above that temperature.  The highest enzyme activity of α-amylase of Anak Daro, Cisokan and Inpari 30 varieties at 48 0C is 0,14 micromol, 0,365 micromol dan 0,191 micromol. In contrast the optimum enzyme activity of α-amylase of Batang Piaman variety at a temperature of 40 0C is 0,237 micromol and when the temperature rises to 48 0C a decrease in the activity of the α-amylation enzyme is 0,138 micromol. The variation in the activity of α-amylase enzymes in the four varieties is probably due to genetic differences and sucrose content. The Batang Piaman and Cisokan varieties can only germinate up to 36 0C, while the Daro and Inpari 30 varieties can germinate up to 40 0C.

2019 ◽  
Vol 2 (1) ◽  
pp. 33-42
Author(s):  
Afrima Sari

The growth and initial development of the plant greatly determines the survival of the plant at the next stage. This initial phase is also the most sensitive phase of abiotic stress. The level of viability and vigor to produce normal sprouts can explain the success of germination. The aim of this research is to study the temperature change to viabilily and vigor in four rice varieties. Research started from January to February 2018 at Seed Technology and Plant Physiology Laboratory Andalas University and Chemistry Laboratory University Of Padang. This research applies Factorial Experiment in Completely Random Design, where the first factor is four levels of rice varieties, Anak Daro, Batang Piaman, Cisokan and Inpari 30. The second factor is temperature level, 28 0C, 32 0C, 36 0C, 40 0C, 44 0C and 48 0C. Viability and vigor decrease when temperature increase. The optimum temperature for rice germination is 28-32 0 C for Anak Daro, 28-36 0 C for Cisokan, at 28 0 C for Batang Piaman and Inpari 30. Anak Daro and Inpari 30 can germinate until 40 0C. The highest vigor index value at 28 0 C in Cisokan and Inpari 30 (89,33 %). At 28-32 0C Cisokan, Batang Piaman and Inpari 30 has been able to germinate on the second day after planting, but Anak Daro can normal germinate on the third day after planting.


2020 ◽  
Vol 27 (6) ◽  
pp. 551-556
Author(s):  
Nidhya N. Joghee ◽  
Gurunathan Jayaraman ◽  
Masilamani Selladurai

Background: Nε-acetyl L-α lysine is an unusual acetylated di-amino acid synthesized and accumulated by certain halophiles under osmotic stress. Osmolytes are generally known to protect proteins and other cellular components under various stress conditions. Objective: The structural and functional stability imparted by Nε-acetyl L-lysine on proteins were unknown and hence was studied and compared to other commonly known bacterial osmolytes - ectoine, proline, glycine betaine, trehalose and sucrose. Methods: Effects of osmolytes on the temperature and pH profiles, pH stability and thermodynamic stability of the model enzyme, α-amylase were analyzed. Results: At physiological pH, all the osmolytes under study increased the optimal temperature for enzyme activity and improved the thermodynamic stability of the enzyme. At acidic conditions (pH 3.0), Nε-acetyl L-α lysine and ectoine improved both the catalytic and thermodynamic stability of the enzyme; it was reflected in the increase in residual enzyme activity after incubation of the enzyme at pH 3.0 for 15 min by 60% and 63.5% and the midpoint temperature of unfolding transition by 11°C and 10°C respectively. Conclusion: Such significant protective effects on both activity and stability of α-amylase imparted by addition of Nε-acetyl L-α lysine and ectoine at acidic conditions make these osmolytes interesting candidates for biotechnological applications.


2018 ◽  
Vol 77 (6) ◽  
pp. 375-381
Author(s):  
K. M. Popov

Abstract. Influence of air temperature on the consumption of fuel and energy resources (FER) on train traction is due to a number of physical laws. The extent of this effect is specified in the Rules for Traction Settlement (RTS). At the same time, when rationing FER consumption for train traction, a specialized methodical base is used, which involves a different approach to accounting for the effect of temperature on FER consumption for train traction. At the same time in different documents of this base, the effects of low temperature on the absolute and specific consumption of fuel and energy resources on train traction are taken into account in a different way, which is due to the lack of consensus among specialists on the way this factor is taken into account. Specialists of JSC “VNIIZhT” carried out an analysis of a significant amount of driver’s routes data, results of which showed that the dependence of the specific flow rate on temperature, on the basis of which the corresponding influence coefficient is determined, needs to be periodically updated. In addition, when technically standardizing the consumption of fuel and energy resources (for the locomotive crew work site), the temperature effect coefficients need to be calculated for a specific work area and direction of motion on it, while using the average network coefficient values will lead to errors. When calculating additional flow of fuel and energy from the effect of temperature for electric multiple units (EMU), the equations of regression dependencies should be used, obtained by statistical processing of data on temperature changes and specific consumption of fuel and energy resources for EMU and determined for each series of EMU when working on a particular suburban area.


Author(s):  
Yiqun Huang ◽  
Pawan Singh Takhar ◽  
Juming Tang ◽  
Barry G Swanson

Rheological behaviors of high acyl (HA) gellan are not well understood partially because of its relatively late commercialization compared to low acyl gellan. The objective of this study was to investigate the effect of temperature (5-30 °C), calcium (0, 1 and 10 mM) and gellan concentrations (0.0044-0.1000% w/v) on the flow behaviors of high acyl gellan aqueous solutions using rheological tests. Gellan solutions with 0 or 1 mM added Ca++ exhibited shear thinning behavior at gellan concentrations above 0.0125%. The influence of temperature on apparent viscosity (shear rate, 100 s-1) of gellan solutions can be described with an Arrhenius relationship. The apparent viscosity of gellan solution at low concentrations was more sensitive to temperature changes. The addition of Ca++ led to a decrease in flow resistance for a dilute gellan solution (<0.0125%), but an increased resistance for a relatively concentrated gellan solution (>0.0125%).


2021 ◽  
Vol 58 (1) ◽  
pp. 43-48
Author(s):  
Dalibha Pathak ◽  
Umesh Ch. Kalita

Sixteen genotypes of rice (including one check) were evaluated on 18 quantitative traits during sali (August), 2018 in a randomized block design with three replications at Instruction cum Research Farm, Department of Plant Breeding and Genetics, Assam Agricultural University, Jorhat to study the nature and magnitude of variability, heritability and genetic advance under delayed sown condition. The analysis of variance for 18 quantitative traits revealed the presence of significant differences for grain yield and its component characters. The highest genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) was observed for chaffs per panicle followed by grains per panicle, spikelet sterility (%), spikelets per panicle, grain yield (kg/ha). A high heritability coupled with high genetic advance was observed for plant height (cm), spikelets per panicle, spikelet sterility (%), chaffs per panicle, grains per panicle, grain yield (g/hill), grain yield (kg/ha), biological yield (kg/ha), straw weight (kg/ha) and harvest index (%) indicating that selection might be effective for improvement of these characters under delayed sown condition with low input. From the findings of this investigation, one genotype viz., Gandhari emerged as the outstanding genotype which yielded 4170 kg/ha and could be directly used for cultivation in delayed sown situation with low inputs. Some other promising genotypes that yielded higher than the check Manoharsali under delayed sown condition were JR 29, JR 16, Basundhara and JR 60 and could be utilized as potential parental material in the hybridization programmes designed to develop suitable rice varieties for delayed sown situation.


2021 ◽  
Vol 66 (1) ◽  
pp. 72-79
Author(s):  
Thuoc Doan Van ◽  
Hung Nguyen Phuc

The effect of physical parameters such as temperature and pH on the production, activity, and stability of α-amylase from Bacillus subtilis V37 was investigated. The results indicated that the optimum culture conditions for enzyme activity were pH 7.0 and 35 oC. The optimum pH and temperature for enzyme activity were 6.0 and 70 oC. The crude enzyme was found to be stable in the pH range of 5.0 to 7.0. The enzyme was stable for 1 h at a temperature from 30 to 80 oC; nearly 100% of enzyme activity remained at temperatures of 30 - 40 oC, and about 34% of original activity remained at a temperature of 80 oC. These features demonstrated that α-amylase from B. subtilis V37 can be applied in many areas such as the food, fermentation, and animal feed industries.


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