scholarly journals Extraction and Characterization of Urease from Durio zibethinus L

2021 ◽  
Vol 7 (2) ◽  
pp. 158-167
Author(s):  
Zusfahair Zusfahair ◽  
Amin Fatoni ◽  
Dian Riana Ningsih ◽  
Mardiyah Kurniasih
Keyword(s):  
Reaction Time ◽  
Metal Ion ◽  
Storage Time ◽  
Incubation Temperature ◽  
Enzymatic Reaction ◽  
Test Analysis ◽  
Germination Time ◽  
Durio Zibethinus ◽  
And Storage

Urease is a biocatalyst that serves to hydrolyze urea into ammonia and carbon dioxide. Since it is an imported product, the price of urea is still high. Urease can be found in grains. One of the grains that has not been explored for its urease content is durian (Durio zibethinus L.) seeds. This study aims to determine the effect of germination time on the activity of urease from durian seeds and its characteristics including the effect of pH, incubation temperature, enzymatic reaction time, addition of EDTA and metals, and storage time on the activity of urease from durian seeds. The first step of this study was seed germination which was carried out in the dark for 0, 3, 5, 7, and 9 days. Durian seed sprouts were extracted by mashing them using a mortar and pestle. They were then homogenized using a stirrer and centrifuged in a cold state. The crude urease extract obtained was then tested for its activity using the Nessler method. The acquired data was tested statistically using ANOVA. The results showed that the activity of urease from durian seeds was optimum at 3-day germination time, pH 7, incubation temperature at 30 °C, and 15-minute enzymatic reaction time with an activity of 163.6 U/mL. Urease is a metalloenzyme with its inhibitor being the Cu2+ and Na+ metal ions and its activator being Ba2+ metal ion. Tukey's test analysis showed that the effect of urease storage time at 4 °C resulted in a stable urease activity for 8 days while at room temperature it decreased its activity significantly to 72.8%.

Preparation and characterization of natural rubber bio-based wood adhesive: effect of total solid content, viscosity, and storage time

2019 ◽  
Vol 77 (5) ◽  
pp. 2737-2747 ◽  
Author(s):  
Siriwat Radabutra ◽  
Pongtanawat Khemthong ◽  
Sayant Saengsuwan ◽  
Sasiwimon Sangya
Keyword(s):  
Natural Rubber ◽  
Storage Time ◽  
Total Solid ◽  
Wood Adhesive ◽  
Solid Content ◽  
Total Solid Content ◽  
Adhesive Effect ◽  
And Storage

scholarly journals MYROSINASE ACTIVITY IN ARMORACIA RUSTICANA

1970 ◽  
Vol 62 ◽  
Author(s):  
Daniela Mucete ◽  
Mariana Poiana ◽  
I. Jianu ◽  
Florina Radu
Keyword(s):  
Reaction Time ◽  
Hplc Analysis ◽  
Enzymatic Reaction ◽  
Maximum Activity ◽  
Spectrophotometric Analysis ◽  
Armoracia Rusticana ◽  
Different Temperatures ◽  
Myrosinase Activity ◽  
Best Parameters

This work is part of a study, which is more complex regarding the activity of sinigrin-myrosinase complex. With the help of this study we are following the optimization and the characterization of myrosinase activity with the help of HPLC chromatography and the comparison of the obtained results by spectrophotometric analysis. At different temperatures conditions, (25°C ÷ 75°C), and reaction time (30 ÷ 390 minutes) were determined sinigrin concentration in extract (CSinExtr) and sinigrin concentration consumed in enzymatic reaction (CSinCons) by HPLC analysis. The appreciation of sinigrin-myrosinase system activity was done by transforming CSinExtr and CSinCons in μg/glucose/g sample*hour. The best parameters, adequate to myrosinase maximum activity, in Armoracia rusticana extracts were the following: pH = 7, temperature of 55°C, and reaction time was of 210 minutes for rubbed out horseradish samples and of 240 minutes for unrubbed horseradish samples.

scholarly journals PEMANFAATAN KITOSAN DARI CANGKANG BEKICOT (Achatina fulica) SEBAGAI PENGAWET IKAN KEMBUNG (Rastrelliger sp) DAN IKAN LELE (Clarias batrachus)

2015 ◽  
Vol 3 (4) ◽  
pp. 51-57
Author(s):  
Sari Wahyu Waryani ◽  
Rika Silvia ◽  
Farida Hanum
Keyword(s):  
Storage Time ◽  
Chitosan Solution ◽  
Clarias Batrachus ◽  
Antimicrobial Compounds ◽  
Optimal Conditions ◽  
Achatina Fulica ◽  
Total Volatile ◽  
And Storage

The efforts that should be made to maintain the quality of fish is by using antimicrobial compounds, one of which is chitosan. In this research, characterization of chitosan from shell snail (Achatina fulica) has a water content of 5.07%, ash content of 1.8% and the degree of deacetylation (DD) 75.13%. The use of chitosan in this study was to determine the optimal conditions on chitosan concentration and storage time of mackerel (Rastrelliger sp) and catfish (Clarias batrachus) from the microbiological and organoleptic aspects. This research used a variation of the concentration of chitosan was 1%, 1.5%, 2% and 2.5% dissolved in 1% acetic acid. Observations were do with variation the storage time 10 hours, 15 hours, 20 hours and 25 hours and the provision of chitosan solution by soaking and spraying with the observation parameters Total Volatile Base (TVB), organoleptic and pH of fish. Based on the analysis, the results showed that the maximum concentration of chitosan on mackerel (Rastrelliger sp) and catfish (Clarias batrachus) is 1,5% and treatment by means of immersion is the best treatment. The use of chitosan solution on mackerel (Rastrelliger sp) survived 20 hours while catfish (Clarias batrachus) survived 15 hours.

scholarly journals Characterization of Tifton 85 bermudagrass haylage with different layers of polyethylene film and storage time

2018 ◽  
Vol 31 (8) ◽  
pp. 1197-1204
Author(s):  
Caroline Daiane Nath ◽  
Marcela Abbado Neres ◽  
Kácia Carine Scheidt ◽  
Luciano dos Santos Bersot ◽  
Samantha Mariana Monteiro Sunahara ◽  
...  
Keyword(s):  
Storage Time ◽  
Polyethylene Film ◽  
And Storage

scholarly journals SINTESIS DAN KARAKTERISASI SIFAT OPTIK POLIMER FILM PVA-TCA-MB

2017 ◽  
Vol 3 (2) ◽  
pp. 257
Author(s):  
Jannatin `Ardhuha ◽  
Ni Nyoman Sri Putu Verawati ◽  
Muhammad Taufik ◽  
Syahrial Ayub
Keyword(s):  
Thin Film ◽  
Methylene Blue ◽  
Absorption Spectrum ◽  
Optical Property ◽  
Polyvinyl Alcohol ◽  
Trichloroacetic Acid ◽  
Storage Time ◽  
Purple Colour ◽  
And Storage

Polyvinyl alcohol (PVA) based film polymers that contain trichloroacetic acid (TCA) and methylene blue (MB) dye has been synthesized. The synthesis aimed to obtain material that can be applied as film dosimeter. Six PVA-TCA-MB thin film samples have been synthsized by varying PVA grades and TCA composition. Characterization of optical property of the resulted polymer was undertaken by measuring samples absorption within wavelength range of 200 nm to 700 nm.  Absorption spectrum of samples showed an optimum between 547-644 nm that corresponds to purple colour and characteristic to MB absoption. Further analysis showed the influence of TCA concentration and storage periode of the polymer. Optimization of syntesis by evaluating synthesis condition, heating and storage time is yet to be done in order to obtain polymer that can be used as dosimeter with reproducible optical property.

Retardation of Surface Adsorption of Trace Metals by Competitive Complexation

1979 ◽  
Vol 33 (1) ◽  
pp. 37-40 ◽  
Author(s):  
William C. Hoyle ◽  
Annette Atkinson
Keyword(s):  
Trace Metals ◽  
Metal Ion ◽  
Storage Time ◽  
Chelating Agents ◽  
Surface Adsorption ◽  
Lead And Cadmium ◽  
Wide Range ◽  
Buffer Composition ◽  
Competitive Complexation ◽  
And Storage

The storage of samples containing trace metals has resulted in the adsorption of certain metals onto the surface of the container. The effect of the adsorption of trace amounts of lead and cadmium on subsequent analyses using atomic absorption spectroscopy was studied. The effects on adsorption by factors such as pH, container composition, buffer composition, metal concentration, and storage time were studied. Significant adsorption of trace amounts of lead and cadmium occurred rapidly onto both Pyrex and polyethylene containers in alkaline solution. Minimization of this adsorptive interference was attempted through the use of organic chelating agents. EDTA and thenoyltrifluoroacetone were utilized to provide retardation of the adsorption via a competitive complexation for the metal ion with the container surface. The presence of thenoyltrifluoroacetone and EDTA, in the otherwise identical solutions, successfully prevented the adsorption onto the surface of the container over a wide range of pH. In addition, the EDTA was also capable of rapidly desorbing lead which had been adsorbed for as long as 40 days on Pyrex and polyethylene surfaces.

Computer Simulation of Amperometric Biosensor Response to Mixtures of Compounds

2002 ◽  
Vol 7 (2) ◽  
pp. 3-14 ◽  
Author(s):  
R. Baronas ◽  
J. Christensen ◽  
F. Ivanauskas ◽  
J. Kulys
Keyword(s):  
Computer Simulation ◽  
Enzymatic Reaction ◽  
Diffusion Equations ◽  
Response Data ◽  
Finite Difference Technique ◽  
Stationary Diffusion ◽  
Biosensor Array ◽  
Menten Kinetic ◽  
Biosensor Response

A mathematical model of amperometric biosensors has been developed. The model bases on non-stationary diffusion equations containing a non-linear term related to Michaelis-Menten kinetic of the enzymatic reaction. The model describes the biosensor response to mixtures of multiple compounds in two regimes of analysis: batch and flow injection. Using computer simulation, large amount of biosensor response data were synthesised for calibration of a biosensor array to be used for characterization of wastewater. The computer simulation was carried out using the finite difference technique.

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