scholarly journals Influence of temperature on the enzymic semisynthesis of human insulin by coupling and transpeptidation methods

1986 ◽  
Vol 240 (3) ◽  
pp. 803-810 ◽  
Author(s):  
K Morihara ◽  
Y Ueno ◽  
K Sakina
Keyword(s):  
Human Insulin ◽  
Temperature Effects ◽  
Enzyme Stability ◽  
Product Yield ◽  
Reaction Conditions ◽  
Influence Of Temperature ◽  
Influence Of Temperature On ◽  
The Stability ◽  
Complex Temperature ◽  
Optimal Reaction

The influence of temperature of enzymic semisynthesis of human insulin ester was determined by using coupling and transpeptidation methods with trypsin and Achromobacter lyticus proteinase I as catalysts. The optimal reaction conditions were studied at the selected temperatures of 25, 12 and 4 degrees C. The results showed that the synthesis rates by both methods with trypsin increased as the temperature increased, but the final product yield correspondingly decreased. Therefore the reaction with trypsin should be done below 12 degrees C, preferably at 4 degrees C. This agrees well with the stability of trypsin at these temperatures. When the catalyst was Achromobacter lyticus proteinase I, no such complex temperature effects were observed, and the findings indicated that the reactions should be conducted below 37 degrees C for enzyme stability.

Influence of Temperature and Oxygen Concentration on the Radiation Induced Oxidation of Phenylalanine

1995 ◽  
Vol 50 (9) ◽  
pp. 864-870 ◽  
Author(s):  
P. Krajnik ◽  
R. M. Quint ◽  
S. Solar ◽  
N. Getoff ◽  
G. Sontag
Keyword(s):  
Oxygen Concentration ◽  
Room Temperature ◽  
Degradation Process ◽  
Storage Conditions ◽  
Food Storage ◽  
Reaction Conditions ◽  
Influence Of Temperature ◽  
Influence Of Temperature On ◽  
Radiation Induced ◽  
Induced Changes

AbstractThe formation of tyrosine isomers by γ-radiolysis of neutral aqueous phenylalanine solutions was found to be strongly dependent on oxygen concentration and temperature. Changing the dose rate did not influence the degradation process. In the presence of 0.25 x 10-3 mol dm-3 oxygen at room temperature the yields of o-tyrosine as well as of m- and p-tyrosine drop from G(o-Tyr) = 0.5 and G(m-Tyr) = G(p-Tyr) = 0.4 at a dose of 0.3 kGy to 0.18 and 0.16 at 2.5 kGy, respectively. In solutions containing 1.25 x 10-3 mol dm-3 oxygen the initial yields remain unchanged but decrease at 2.5 kGy only to G(o-Tyr) = 0.3 and G(m-Tyr) = G(p-Tyr) = 0.20. Under the latter reaction conditions also 3,4-dihydroxyphenylalanine was found.Samples irradiated in frozen state did not show remarkable radiolysis of phenylalanine and tyrosine formation. In the range between 5 and 20°C no essential influence of temperature on the phenylalanine radiolysis and tyrosine yields was observable. The obtained results are important for methods using the tyrosine yields as markers for the detection of irradiated food. Storage conditions and irradiation temperature play an essential role on radiation induced changes of food.

scholarly journals The Influence of Temperature on Metabolisms of Phosphorus Accumulating Organisms in Biological Wastewater Treatment Plants in the Presence of Cu(II) Toxicity

2019 ◽  
Vol 9 (6) ◽  
pp. 1126 ◽  
Author(s):  
Chen-Chiang Chou ◽  
Chih-Chi Yang ◽  
Meng-Shan Lu ◽  
Li-Yuan Hu ◽  
Ku-Fan Chen ◽  
...  
Keyword(s):  
Temperature Effects ◽  
Shock Loading ◽  
Wastewater Treatment Plants ◽  
Glycogen Synthesis ◽  
Phosphorus Uptake ◽  
Phosphorus Release ◽  
Biological Wastewater Treatment ◽  
Influence Of Temperature ◽  
Toxic Environment ◽  
Influence Of Temperature On

The purpose of this study was to study how temperature variation affects the tolerance of phosphorus accumulating organisms (PAOs) in a toxic environment. To exclude the interference of glycogen accumulating organisms (GAOs), shock loading experiments were conducted to study the effect of Cu(II) toxicity on the metabolisms of PAOs in 10, 20, and 30 °C conditions. The experimental data showed that the temperature effects on aerobic phosphorus uptake, PHA degradation, and glycogen synthesis were remarkable in the presence of Cu(II). Nevertheless, insignificant effects on anaerobic phosphorus release and PHA synthesis were found. The largest inhibition of PAO metabolism occurred in the low temperature case (10 °C). This study also experimentally demonstrated the loss of PAO metabolic ability in the subsequent aerobic stage, after the anaerobic stage. The presence of Cu(II) toxicity mainly resulted from the inhibition of biochemical reactions in the aerobic stage, and it was irrelevant to the inhibition of previous anaerobic metabolisms.

Synthesis of Butanone 1,2 - Propanediol Ketal by Sulfamic Acid as Catalyzed

2013 ◽  
Vol 781-784 ◽  
pp. 276-279
Author(s):  
Yu Hang Zhao ◽  
Li Cui ◽  
Da Zhi Wang ◽  
Tong Kuan Xu ◽  
Yong Peng Li
Keyword(s):  
Reaction Time ◽  
Reaction Temperature ◽  
Raw Materials ◽  
Sulfamic Acid ◽  
Product Yield ◽  
Experimental Results ◽  
Reaction Conditions ◽  
Optimal Reaction

Butanone 1,2-propanediol ketal was synthesized by butanone and 1,2-propanediol as raw materials and sulfamic acid as catalyst. The effects of the mole ratio of raw materials agent, the dosage of the water-carrying agent and catalyst, reaction time on the product yield were discussed separately. Experimental results showed that sulfamic acid was a suitable catalyst for synthesizing of butanone 1,2-propanediol ketal. And the optimal reaction conditions are as follows: the mole ratio of butanone to 1,2-propanediol is 1:1.5, the amount of the catalyst is 2.2%, the water-carrying agent is 25ml, the reaction temperature is 358-378K and reaction time 3h. In this condition, the yield of production could reach 93.8%.

Preparation of aqueous polyaniline-vesicle suspensions with class III peroxidases. Comparison between horseradish peroxidase isoenzyme C and soybean peroxidase

2013 ◽  
Vol 67 (8) ◽  
Author(s):  
Katja Junker ◽  
Ivan Gitsov ◽  
Nick Quade ◽  
Peter Walde
Keyword(s):  
Horseradish Peroxidase ◽  
Enzyme Stability ◽  
Class Iii ◽  
Salt Form ◽  
Reaction Conditions ◽  
Soybean Peroxidase ◽  
Peroxidase Isoenzyme ◽  
Complete Inactivation ◽  
Class Iii Peroxidases ◽  
Optimal Reaction

AbstractAniline was polymerised enzymatically in aqueous solution at pH = 4.3 and 25°C in the presence of submicrometer-sized vesicles formed from sodium bis(2-ethylhexyl)sulphosuccinate (AOT). H2O2 served as oxidant and the enzyme used was either horseradish peroxidase isoenzyme C (HRPC) or soybean peroxidase (SBP), both being class III peroxidases. From previous studies with HRPC, it is known that stable vesicle suspensions containing the emeraldine salt form of polyaniline (PANI-ES) can be obtained within 1–2 days with a 90–95 % yield, provided that optimal reaction conditions are applied. Unfortunately, HRPC becomes inactivated during polymerisation. In the present study, a linear dendritic block copolymer was added to HRPC, resulting in higher operational enzyme stability; the stabilising effect, however, was too small to afford a substantial decrease in the required amount of enzyme. Moreover, replacing HRPC with SBP was of no advantage, although SBP is known to be more stable towards inactivation by H2O2 than HRPC. By contrast, SBP was found to be much slower in oxidising aniline, and complete inactivation of SBP occurred before all the aniline monomers were oxidised, leading to low yields and the formation of over-oxidised products. The same was observed for HRP isoenzyme A2. Reactions without vesicles indicated that peroxidase inactivation was probably caused by PANI-ES.

scholarly journals Temperature effects on Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis

2003 ◽  
Vol 46 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Arlei Maceda ◽  
Celso L Hohmann ◽  
Honório R. dos Santos
Keyword(s):  
Temperature Effects ◽  
Entire Temperature Range ◽  
Temperature Threshold ◽  
Trichogramma Pretiosum ◽  
Degree Days ◽  
Parasitoid Species ◽  
Influence Of Temperature ◽  
Anagasta Kuehniella ◽  
Influence Of Temperature On ◽  
Lepidoptera Pyralidae

The influence of temperature on lifetime attributes of Trichogramma pretiosum Riley and Trichogrammatoidea annulata De Santis (Hymenoptera: Trichogrammatidae) was evaluated at four constant temperatures (15, 20, 25, and 30º C), RH 70 ± 10%, photophase 14 h. Anagasta kuehniella (Lepidoptera: Pyralidae) eggs were used as hosts. Developmental times of both parasitoid species were similar when exposed to 20, 25, or 30º C. T. annulata, however, developed slightly faster than T. pretiosum at 15º C. Emergence rates of both species were above 89%. The temperature threshold for T. pretiosum and T. annulata was 11º C and the number of degree-days required for their development was 126.9 and 122.3, respectively. Parasitization was maximal at 25º C. T. annulata, however, parasitized significantly more hosts than T. pretiosum in the entire temperature range. Temperature had no effect in brood size.T. annulata progeny consisted predominantly of males, except at 15º C, whereas in T.pretiosumitconsisted predominantly of females, except at 30º C. Parental females lived longer than males.

The Influence of Different Stirring Methods on Crystallization Process of Ammonium Persulfate

2013 ◽  
Vol 634-638 ◽  
pp. 1672-1676
Author(s):  
Yu Guang Fan ◽  
He Wei Hua ◽  
Bing Chen ◽  
San Ping Zhou ◽  
Hong Xian Lin
Keyword(s):  
Crystallization Process ◽  
Ammonium Persulfate ◽  
Influence Of Temperature ◽  
Influence Of Temperature On ◽  
Mixing Method ◽  
The Stability

Thorough research is performed on crystallization process of ammonium persulfate，the influence of different mixing method on crystallization process of the ammonium persulfate is discussed in this paper, the influence of temperature on crystallization process is also discussed, and then the optimum mixing method for the crystallization of ammonium persulfate is achieved. All these will do great favor to improve the stability of crystallization process of ammonium persulfate .

The Influence of Temperature on the Lateral Photovoltaic Effect in the Fe3O4/SiO2/n-Si Structure

2020 ◽  
Vol 312 ◽  
pp. 92-97
Author(s):  
Tatiana A. Pisarenko ◽  
Vladimir V. Korobtsov ◽  
Vyacheslav V. Balashev ◽  
Artem A. Dimitriev
Keyword(s):  
Energy Band ◽  
Temperature Effects ◽  
Photovoltaic Effect ◽  
Strong Dependence ◽  
Equivalent Circuits ◽  
Film Resistance ◽  
Temperature Changes ◽  
Influence Of Temperature ◽  
Influence Of Temperature On ◽  
Magnetite Film

We report on the results of a study of the lateral photovoltaic effect in the Fe3O4/SiO2/n-Si(001) structure at temperatures of 300 and 122 K under continuous and pulsed illumination. It is found that when the temperature changes from 300 to 122 K, the LPE sensitivity decreases from 112 to 65 mV/mm. At pulsed illumination, an increase of rise time and a fall time is observed with decreasing temperature. From a consideration of the energy band diagrams and equivalent circuits of the Fe3O4/SiO2/n-Si structure, it is assumed that the detected temperature effects of LPE are due to the strong dependence of the magnetite film resistance on temperature.

Synthesis of Benzaldehyde 1, 2-Propanediol Acetal by Using Ionic Liquid [Hmim]HSO4 as Catalyst

2012 ◽  
Vol 550-553 ◽  
pp. 400-403 ◽  
Author(s):  
Xue Nan Sun ◽  
Li Cui ◽  
Tong Kuan Xu ◽  
Da Zhi Wang
Keyword(s):  
Ionic Liquid ◽  
Reaction Time ◽  
Reaction Temperature ◽  
Raw Materials ◽  
Product Yield ◽  
Experimental Results ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Good Catalyst ◽  
Optimal Reaction

Benzaldehyde 1, 2-propanediol acetal was synthesized from benzaldehyde and 1, 2-propanediol in the presence of ionic liquid [HMIM]HSO4. The effect of the amount of catalyst, reaction time, reaction temperature, and the molar ratio of raw materials agent on the product yield was investigated respectively. Experimental results demonstrate that ionic liquid [HMIM]HSO4is a good catalyst for preparation of benzaldehyde 1, 2-propanediol acetal. Results showed the optimal reaction conditions are as follows: the mole ratio of benzaldehyde to 1, 2-propanediol is 1：1.3, the amount of catalyst is 3.0g, the reaction temperature is 343K, and the reaction time is 4h. The achieved yield of acetal is 78. 7%.

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