scholarly journals Imobilisasi Enzim Lipase Dedak Padi (Oryza Sativa L.) Pada Karbon Aktif: Karakterisasi, dan Uji Stabilitas Kerja Enzim Imobil

2017 ◽  
Vol 5 (1) ◽  
pp. 32-36 ◽  
Author(s):  
Firdaus Firdaus ◽  
Seniwati Dali ◽  
Hendra J. Rusman
Keyword(s):  
Thermal Stability ◽  
Oryza Sativa L ◽  
Carbon Matrix ◽  
Enzyme Characterization ◽  
Relative Activity ◽  
Ph Optimum ◽  
Repeated Use ◽  
The Stability ◽  
Matrix Enzyme

This research aims to immobilization; characterize the enzyme of immobilized, test the effectiveness of the enzyme of immobilized. This research begins with the immobilization to process of enzyme lipase using activated carbon matrix, enzyme characterization covering of immobile determination of temperature and pH optimum of the enzyme of immobilized, as well as test the stability of work covering immobilized of enzyme the test thermal stability and repeated use. The results showed that the immobile of enzyme work optimally at 50oC of temperature and pH 6.5 with each activity 0.040 U/mL; research results also showed that the immobile of enzyme has higher thermal stability in comparison with the free enzyme: with the relative activity of 57.50% at the time of 45 minutes of exposure and the exposure time at 47.50% at 75-105 minutes and it can be used as many as six times with the relative activity of 52.5% in 6 times of use.

scholarly journals Immobilization of Isolated Lipase From Moldy Copra(Aspergillus Oryzae)

2011 ◽  
Vol 8 (2) ◽  
pp. 896-902
Author(s):  
Seniwati Dali ◽  
A. B. D. Rauf Patong ◽  
M. Noor Jalaluddin ◽  
Pirman ◽  
Baharuddin Hamzah
Keyword(s):  
Thermal Stability ◽  
Aspergillus Oryzae ◽  
Immobilized Lipase ◽  
Optimum Temperature ◽  
Adsorption Method ◽  
Ph Optimum ◽  
Optimum Ph ◽  
Recovery Technique ◽  
Free Lipase

Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase fromAspergillus oryzae. Lipase was partially purified from the culture supernatant ofAspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum temperature, thermal stability and reusability were carried out. The results showed that free lipase had optimum pH 8,2 and optimum temperature 35 °C while the immobilized lipase had optimum 8,2 and optimum temperature 45 °C. The thermal stability of the immobilized lipase, relative to that of the free lipase, was markedly increased. The immobilized lipase can be reused for at least six times.

SOME OBSERVATIONS ON THE PANCREATIC AMYLASE AND INTESTINAL MALTASE OF THE CHICK

1963 ◽  
Vol 41 (1) ◽  
pp. 2107-2121 ◽  
Author(s):  
B. M. Laws ◽  
J. H. Moore
Keyword(s):  
Small Intestine ◽  
Amylase Activity ◽  
Pancreatic Amylase ◽  
Ph Optimum ◽  
Modified Method ◽  
Mucosal Cells ◽  
Small Intestinal ◽  
The Stability ◽  
Hydrolysis Of

The digestive enzymes amylase and maltase were studied in acetone-dried powders or homogenates of the pancreatic and small intestinal tissues and small intestinal contents obtained from chicks of various ages. The stability of pancreatic amylase, which was relatively low in 0.15 M sodium chloride, was increased markedly by the presence of 0.02 M barbiturate buffer. The pH optimum of pancreatic amylase (chloride-activated) was 7.0 whereas that of intestinal maltase was 6.9. High levels of pancreatic amylase activity were found in the newly-hatched chick but these levels decreased during the following 20 days and then remained constant. The contrast between the high amylase and low maltase activities in the contents of the small intestine suggested that molecules of maltose, formed by the hydrolysis of starch, were absorbed as such by the mucosal cells. It appeared that maltose could be absorbed with equal facility from all sections of the small intestine of the 10-day-old chick but in the older birds maltose absorption seemed to occur more readily from the upper small intestine than from the duodenum and lower small intestine. A modified method for the determination of maltase activity is described.

scholarly journals Determination of the chemical and hydrothermal stability of the Claus catalyst

2021 ◽  
Vol 264 ◽  
pp. 01023
Author(s):  
Farkhod Yusupov ◽  
Murodali Mamanazarov ◽  
Bobomurod Xursandov ◽  
Gulnoza Baimatova
Keyword(s):  
Thermal Stability ◽  
Water Vapor ◽  
Raw Materials ◽  
Hydrothermal Stability ◽  
Catalyst Activation ◽  
Claus Process ◽  
Tio2 Catalyst ◽  
So2 Adsorption ◽  
The Stability

The hydrothermal and thermal stability used in the Claus process are important indicators in their workflow. In this work, the stability of two catalyst samples obtained from local raw materials was studied. The samples were processed with SO2 / O2 oxides and water vapor, and their properties were studied. As a result, SO2 adsorption reduced catalyst activation. The process is reductive; the recovery of catalyst activation by reducing SO2 in the system has been determined. The stability of sulfation of MgO / TiO2 catalyst in comparison with CaO / V2O5 samples was also determined.

scholarly journals Laccase Immobilized Fe3O4-Graphene Oxide Nanobiocatalyst Improves Stability and Immobilization Efficiency in the Green Preparation of Sulfa Drugs

Catalysts ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 459 ◽  
Author(s):  
Shamila Rouhani ◽  
Shohreh Azizi ◽  
Rose W. Kibechu ◽  
Bhekie B Mamba ◽  
Titus A. M. Msagati
Keyword(s):  
Storage Conditions ◽  
Relative Activity ◽  
The Novel ◽  
Original Activity ◽  
Immobilized Laccase ◽  
Time Period ◽  
Repeated Use ◽  
Graphene Nanocomposite ◽  
The Stability ◽  
And Storage

This paper, reports on the novel and green synthesis procedure for sulfonamides that involved the immobilization of Trametes Versicolor laccase onto the Fe3O4–graphene nanocomposite via glutaraldehyde (GA) crosslinking (Lac/Fe3O4/GO). Various parameters, mainly, activation time, GA, and laccase concentration were investigated and optimized. The results showed that the optimal contact time was 4 h, GA concentration was 5% while laccase concentration was 5 mg·mL−1, at which a high enzyme activity recovery was achieved (86%). In terms of the stability of immobilized laccase to temperature and storage conditions, the performance of the nanobiocatalyst was found to significantly exceed that of free laccase. The results have indicated that nearly 70% of relative activity for immobilized laccase remained after the incubation period of 2 h at 55 °C, but only 48% of free laccase remained within the same time period. Moreover, the immobilized laccase retained 88% of its initial activity after storage for 20 days. In case of the free laccase, the activity retained within the same time period was 32%. In addition, the nanobiocatalyst possessed better recycling performance as evidenced from the observation that after eight cycles of repeated use, it retained 85% of its original activity.

SOME OBSERVATIONS ON THE PANCREATIC AMYLASE AND INTESTINAL MALTASE OF THE CHICK

1963 ◽  
Vol 41 (10) ◽  
pp. 2107-2121 ◽  
Author(s):  
B. M. Laws ◽  
J. H. Moore
Keyword(s):  
Small Intestine ◽  
Amylase Activity ◽  
Pancreatic Amylase ◽  
Ph Optimum ◽  
Modified Method ◽  
Mucosal Cells ◽  
Small Intestinal ◽  
The Stability ◽  
Hydrolysis Of

The digestive enzymes amylase and maltase were studied in acetone-dried powders or homogenates of the pancreatic and small intestinal tissues and small intestinal contents obtained from chicks of various ages. The stability of pancreatic amylase, which was relatively low in 0.15 M sodium chloride, was increased markedly by the presence of 0.02 M barbiturate buffer. The pH optimum of pancreatic amylase (chloride-activated) was 7.0 whereas that of intestinal maltase was 6.9. High levels of pancreatic amylase activity were found in the newly-hatched chick but these levels decreased during the following 20 days and then remained constant. The contrast between the high amylase and low maltase activities in the contents of the small intestine suggested that molecules of maltose, formed by the hydrolysis of starch, were absorbed as such by the mucosal cells. It appeared that maltose could be absorbed with equal facility from all sections of the small intestine of the 10-day-old chick but in the older birds maltose absorption seemed to occur more readily from the upper small intestine than from the duodenum and lower small intestine. A modified method for the determination of maltase activity is described.

scholarly journals IMMOBILIZATION OF PAPAIN ON CHITOSAN

2010 ◽  
Vol 8 (3) ◽  
pp. 372-376
Author(s):  
Sari Edi Cahyaningrum ◽  
Narsito Narsito ◽  
Sri Juari Santoso ◽  
Rudiana Agustini
Keyword(s):  
Thermal Stability ◽  
Optimum Temperature ◽  
Ph Optimum ◽  
Optimum Ph ◽  
Thermal Stability Of

In this study, papain was immobilized on chitosan with Mg(II) cosslinked agent. Studies on free and immobilized papain systems for determination of optimum pH, optimum temperatur, thermal stability and reusability were carried out. The results showed that free papain had optimum pH 6.5 and optimum temperature 55 °C while the immobile papain hadoptimum pH 8 and optimum temperature 80 °C. The thermal stability of the immobilized papain, relative to that of the free papain, was markedly increased. The immobilized papain can be reused for at least six times.   Keywords: papain, immobilization, chitosan

Determining the Norton’s Equivalent Model of Distribution System with Distributed Generation (DG) for Stability Analysis

2019 ◽  
Vol 12 (2) ◽  
pp. 190-198
Author(s):  
Sunny Katyara ◽  
Lukasz Staszewski ◽  
Faheem Akhtar Chachar
Keyword(s):  
Distributed Generation ◽  
Normal Condition ◽  
Distribution System ◽  
Distribution Networks ◽  
Equivalent Model ◽  
Stability Factor ◽  
Matlab Simulation ◽  
The Stability ◽  
Stability Issues

Background: Since the distribution networks are passive until Distributed Generation (DG) is not being installed into them, the stability issues occur in the distribution system after the integration of DG. Methods: In order to assure the simplicity during the calculations, many approximations have been proposed for finding the system’s parameters i.e. Voltage, active and reactive powers and load angle, more efficiently and accurately. This research presents an algorithm for finding the Norton’s equivalent model of distribution system with DG, considering from receiving end. Norton’s model of distribution system can be determined either from its complete configuration or through an algorithm using system’s voltage and current profiles. The algorithm involves the determination of derivative of apparent power against the current (dS/dIL) of the system. Results: This work also verifies the accuracy of proposed algorithm according to the relative variations in the phase angle of system’s impedance. This research also considers the varying states of distribution system due to switching in and out of DG and therefore Norton’s model needs to be updated accordingly. Conclusion: The efficacy of the proposed algorithm is verified through MATLAB simulation results under two scenarios, (i) normal condition and (ii) faulty condition. During normal condition, the stability factor near to 1 and change in dS/dIL was near to 0 while during fault condition, the stability factor was higher than 1 and the value of dS/dIL was away from 0.

Synthesis and solvatochromic studies of 2- amino-3-phenolazo1-(4-sulfophenyl)-3-methyi-5-pyrozolone and use it for the determination of trace amount of Nickel (II) in blood samples

2016 ◽  
Vol 5 (10) ◽  
pp. 4920
Author(s):  
Amar M. Ali ◽  
Hussain. J. Mohammed*
Keyword(s):  
Stability Constant ◽  
Trace Amount ◽  
Benzenesulfonic Acid ◽  
Determination Method ◽  
Blood Samples ◽  
Determination Of Nickel ◽  
Normal Human ◽  
The Stability ◽  
Normal Human Blood

A new, simple, sensitive and rapid spectrophotometric method is proposed for the determination of trace amount of Nickel (II). The method is based on the formation of a 1:2 complex with 4-(4-((2-hydroxy-6-nitrophenyl) diazenyl) -3-methyl-5-oxo-2, 5-dihydro-1H-pyrazol-1-yl) benzenesulfonic acid (2-ANASP) as a new reagent is developed. The complex has a maximum absorption at 516 nm and εmax of 1. 84 X 105 L. mol-1. cm-1. A linear correlation (0. 25 – 4. 0μg. ml-1) was found between absorbance at λmax and concentration. The accuracy and reproducibility of the determination method for various known amounts of Nickel (II) were tested. The results obtained are both precise (RSD was 1. 2 %) and accurate (relative error was 0. 787 %). The effect of diverse ions on the determination of Nickel (II) to investigate the selectivity of the method were also studied. The stability constant of the product was 0. 399 X 106 L. mol-1. The proposed method was successfully applied to the analysis of diabetes blood and normal human blood. 

Polarographic study of hydrolysis of [8-lysine]vasopressin and its derivatives with blood serum of pregnant women

1980 ◽  
Vol 45 (4) ◽  
pp. 1099-1108 ◽  
Author(s):  
Mikuláš Chavko ◽  
Michal Bartík ◽  
Evžen Kasafírek
Keyword(s):  
Blood Serum ◽  
Pregnant Women ◽  
Degree Of Hydrolysis ◽  
Polarographic Study ◽  
Ph Optimum ◽  
Lysine Vasopressin ◽  
Rate Of Hydrolysis ◽  
Hydrolysis Of ◽  
Vasopressin Analogues

A polarographic study of the hydrolysis of [8-lysine]vasopressin and some hormonogens of the vasopressin series with the blood serum of women in the last week of pregnancy was studied. The dependence of hydrolysis on pH (pH optimum: 7.4-7.50, substrate concentration (Km 1.2 . 10-5M), pH stability and thermal stability were determined. The rate of hydrolysis of individual vasopressin analogues decreases in the order: [8-lysine]vasopressin > Nα-glycyl-prolyl[8-lysine]-vasopressin > Nα-leucyl-[8-lysine]vasopressin > Nα-alanyl-[8-lysine]vasopressin > Nα-phenyl alanyl-[8-lysine]vasopressin > Nα-diglycyl-[8-lysine]vasopressin > Nα-prolyl-[8-lysine]vasopressin > Nα-triglycyl-[8-lysine]vasopressin > Nα-sarcosyl-glycyl-[8-lysine]vasopressin. The degree of hydrolysis gradually increases to a multiple with the length of the pregnancy in consequence of the presence of oxytocine. However, vasopressin is also hydrolysed to a small extent with the enzymes from the blood sera of non-pregnant women. Under similar analytical conditions oxytocin was not hydrolysed with the sera of non-pregnant women and therefore oxytocin is a more suitable substrate than vasopressin for polarographic determination of serum oxytocinase.

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