scholarly journals Degradation of dyes using crude extract and a thermostable and pH-stable laccase isolated from Pleurotus nebrodensis

2016 ◽  
Vol 36 (4) ◽  
Author(s):  
Xianghe Yuan ◽  
Guoting Tian ◽  
Yongchang Zhao ◽  
Liyan Zhao ◽  
Hexiang Wang ◽  
...  
Keyword(s):  
Crude Extract ◽  
Simple Structure ◽  
Reaction System ◽  
Potential Mechanism ◽  
Duration Of Treatment ◽  
Colour Removal ◽  
Pleurotus Nebrodensis ◽  
Degradation Of Dyes ◽  
Amine Groups ◽  
Short Time

Three laccase isoenzymes (Lac1, Lac2 and Lac3) have been purified to homogeneity from Pleurotus nebrodensis in our previous study. Lac2 was shown to be the dominant isoform, capable of oxidizing the majority of laccase substrates and manifesting good thermostability and pH stability. Hence, Lac2 was selected to decolourize structurally different dyes and the colour removal efficiencies of Lac2 and the crude extract of P. nebrodensis were compared. By monitoring the λmax of the reaction system during the course of biotransformation, clear hypsochromic shifts were observed for most of the dyes examined, illustrating that at least one peak disappeared as a result of laccase treatment. In general, Lac2 was more efficient within a short time (1 h) and the crude extract, in general, could achieve similar or even higher efficiency when the duration of treatment was extended to 24 h. Malachite green (MG) was chosen to study the detoxifying potential of Lac2, because of the relatively simple structure and high toxicity of the dye towards microorganisms. The toxicity of MG towards both bacteria (Bacillus subtilis, Bacillus licheniformis, Pseudomonas fluorescens and Escherichia coli) and fungi (Fusarium graminearum and Trichoderma harzianum) was dramatically decreased and the potential mechanism was estimated by GC–MS as to remove four methyl groups firstly and the two newly formed amine groups would be degraded or polymerized further. The present study facilitates an understanding of the application of P. nebrodensis laccases and furnishes evidence for the safety of their utilization in the treatment of wastewater emanating from textile industries.

Factors affecting colour removal from reactive dye bath by ozonation

2002 ◽  
Vol 45 (12) ◽  
pp. 261-270 ◽  
Author(s):  
I. Kabdaşlı ◽  
T. Ölmez ◽  
O. Tünay
Keyword(s):  
Initial Rate ◽  
Chelating Agent ◽  
Reactive Dye ◽  
Slight Effect ◽  
Colour Removal ◽  
Factors Affecting ◽  
Synthetic Dye ◽  
Ozone Dose ◽  
Short Time

A reactive dye bath sample containing a mixture of dyes was ozonated and colour removal was obtained in a relatively short time of 30 min at 605 mgl-1 of ozone utilisation. The factors affecting ozonation were assessed by comparing the results of dye bath and synthetic samples. Results from dye bath and synthetic dye solution ozonation were found to be significantly different. NaCl and Na2CO3 were determined to have a slight effect only on the initial rate of ozonation. However, the effect of the chelating agent in terms of both time and ozone dose was significant and explained the differences between the results of the dye bath and dye solution ozonation.

Design of an Air-Starter Turbine and Starting Performance Prediction Through the Numerical Analysis

2015 ◽  
Author(s):  
JaeHyeon Park ◽  
Sooyoung Park ◽  
JeHyun Baek
Keyword(s):  
Numerical Analysis ◽  
Simple Structure ◽  
Minimum Length ◽  
Heavy Duty ◽  
Ansys Cfx ◽  
Air Turbine ◽  
Flow Through ◽  
Starting Process ◽  
Short Time ◽  
Shock Loss

To get the required power, a procedure for starting an engine is required. For an engine of the large ship or land-based power plant, two kinds of mechanisms exist: one is to use an electric motor and the other air-starter. As one of the starting methods of heavy-duty engines, the air-starter gives rotating power from the blade lifting force by the compressed air flow through the turbine to rotate the stopped engine. Since the air turbine has a large weight-to-power ratio, simple structure and is spark-free, many heavy-duty engine are equipped with this device for their starting process. In order to get high enough power required to rotate the engine up to sufficient speed in a short time, high instantaneous torque is required. An impulsive supersonic turbine can be applied for this purpose. In this case, an one-stage air turbine with a minimum length convergent-divergent nozzle and transition arc shaped rotor was utilized to reduce shock loss. The performance of the desired turbine is evaluated numerically and compared with experimental results. The spin-down test is performed to estimate the performance of the designed turbine and numerical analysis is performed using the commercial tool ANSYS CFX.

Activity Comparison of Acidic Resins in the Production of Valuable Glycerol Acetates

2016 ◽  
Vol 14 (1) ◽  
pp. 309-314 ◽  
Author(s):  
Emine Kaya Ekinci ◽  
Gamze Gündüz ◽  
Nuray Oktar
Keyword(s):  
Exchange Resin ◽  
Heterogeneous Reaction ◽  
Reaction System ◽  
Ion Exchange Resin ◽  
Molar Ratio ◽  
Glycerol Conversion ◽  
Amberlyst 15 ◽  
Time Period ◽  
Short Time ◽  
Activity Comparison

AbstractAcetates of glycerol have been produced in a heterogeneous reaction system using acidic ion-exchange resin catalysts; Amberlyst-15 (A-15), Amberlyst-16 (A-16), Amberlyst-36 (A-36), Amberlite-IR 120 (A-IR 120) and Relite-EXC8D (R-EXC8D). Effect of reaction temperature on glycerol conversion and product (mono, di and tri glycerol acetates) selectivities were investigated via reaction experiments conducted with glycerol to acetic acid initial molar ratio (G/Ac) of 1/6. Increase in glycerol conversion with an increase in temperature was observed for all catalysts. Among the catalysts investigated, R-EXC8D exhibited the highest activity in the temperature range of 95–150°C. Reaction was completed within a 25 minute short time period.

Effects of the Cobalt Ion on the in Vitro Growth of Mouse Fetus Fibroblasts.

1975 ◽  
Vol 61 (4) ◽  
pp. 327-332
Author(s):  
Giovanni Brambilla ◽  
Maria Cristina Boaretto ◽  
Claudia Bolognesi
Keyword(s):  
Plating Efficiency ◽  
Low Doses ◽  
In Vitro Growth ◽  
Duration Of Treatment ◽  
Mouse Fetus ◽  
Established Line ◽  
Embryo Cells ◽  
Short Time ◽  
Higher Doses

The effect of cobalt II (CoCl2.6 H2O) on growth and plating efficiency of an established line of BALB/c mouse embryo cells was examined. The degree of inhibition of cell proliferation was dependent on both cobaltous ion dose and duration of treatment. Plating efficiency was enhanced by low doses and/or short time of exposure, but was reduced by treatment with higher doses or of longer duration.

scholarly journals Extraction and Application of Laccases from Shimeji Mushrooms (Pleurotus ostreatus) Residues in Decolourisation of Reactive Dyes and a Comparative Study Using Commercial Laccase from Aspergillus oryzae

2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
Ricardo Sposina S. Teixeira ◽  
Patrícia Maia Pereira ◽  
Viridiana S. Ferreira-Leitão
Keyword(s):  
Reaction Time ◽  
Comparative Study ◽  
Organic Pollutants ◽  
Aspergillus Oryzae ◽  
Crude Extract ◽  
Pleurotus Ostreatus ◽  
Sulfonic Acid ◽  
Reactive Dyes ◽  
Colour Removal

Oxidases are able to degrade organic pollutants; however, high costs associated with biocatalysts production still hinder their use in environmental biocatalysis. Our study compared the action of a commercial laccase from Aspergillus oryzae and a rich extract from Pleurotus ostreatus cultivation residues in decolourisation of reactive dyes: Drimaren Blue X-3LR (DMBLR), Drimaren Blue X-BLN (DMBBLN), Drimaren Rubinol X-3LR (DMR), and Drimaren Blue C-R (RBBR). The colour removal was evaluated by considering dye concentration, reaction time, absence or presence of the mediator ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), and the source of laccase. The presence of ABTS was essential for decolourisation of DMR (80–90%, 1 h) and RBBR (80–90%, 24 h) with both laccases. The use of ABTS was not necessary in reactions containing DMBLR (85–97%, 1 h) and DMBBLN (63–84%, 24 h). The decolourisation of DMBBLN by commercial laccase showed levels near 60% while the crude extract presented 80% in 24 h.

scholarly journals One-Step and Colorimetric Detection of Fish Freshness Indicator Hypoxanthine Based on the Peroxidase Activity of Xanthine Oxidase Grade I Ammonium Sulfate Suspension

2021 ◽  
Vol 12 ◽  
Author(s):  
Chen Guo ◽  
Shuhan You ◽  
Changmei Li ◽  
Tiantian Chen ◽  
Xiudan Wang
Keyword(s):  
Xanthine Oxidase ◽  
Ammonium Sulfate ◽  
Peroxidase Activity ◽  
Colorimetric Detection ◽  
Reaction System ◽  
Sea Bass ◽  
Fish Samples ◽  
One Step ◽  
Color Reactions ◽  
Short Time

The global food waste problem, especially aquatic product spoilage, stimulates the accurate freshness analysis of food products. However, it still remains a great challenge to realize in-field determination of fish freshness at the time of use. In the present study, a colorimetric enzyme biosensor was developed for one-step detection of hypoxanthine (Hx), which is an important intermediate of adenosine triphosphate decomposition during fish storage. We demonstrate that xanthine oxidase grade I ammonium sulfate suspension (XOD-ASS) possesses peroxidase activity. It can oxidize different peroxidase substrates, including 3,3′,5,5′-tetramethylbenzidine, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, and o-phenylenediamine in the presence of H2O2, producing visible color reactions. Further experiments indicate that XOD-ASS displayed effective peroxidase activity and could be used for H2O2 detection. Based on this, a one-step Hx detection method was established using only XOD-ASS as the catalyst. The method displays a good linear relationship in the range from 20 to 100 μM with a detection limit of 6.93 μM. Additionally, we successfully applied this method in testing Hx accumulation in sea bass fish samples of different storage times. The recovery values range from 97.44 to 102.56%. It is exciting to note that, compared with other methods, our proposed method provides a robust advantage on the economic reaction system, ease of preparation, short time consumption, and moderate reaction temperature. We believe that this method shows good application prospects for on-site fish freshness determination.

scholarly journals Surgical Orthodontics: A Case Report

2017 ◽  
Vol 16 (2) ◽  
Author(s):  
Wael Mohamed ◽  
Rozita Hassan ◽  
Shaifulizan Ab. Rahman
Keyword(s):  
Case Report ◽  
Orthodontic Treatment ◽  
Tooth Movement ◽  
Treatment Time ◽  
Duration Of Treatment ◽  
Orthodontic Patients ◽  
Chain Complete ◽  
Anchorage Loss ◽  
Short Time ◽  
New Surgical Technique

Introduction: Duration of treatment is one of the things orthodontic patients complaint about most and challenging orthodontist to shorten treatment time. A new surgical technique was introduced to accelerate tooth movement during orthodontic treatment through combining surgical and orthodontic treatment by doing surgical reduction of the bone mass in the path of desired tooth movement prior to start orthodontic alignment of the teeth. This case report showed treatment of 21 years old male patient complaint of teeth malalignment and he requested to finish treatment in short time. Upper right first premolar and lower left second premolar were extracted, all the bones in the desired path of tooth movement was removed and the dentoalveolar distraction procedure was performed using Nickel Titanium closing coil spring and power chain. Complete teeth alignment was achieved in two months period and the anchorage teeth were able to withstand the retraction forces with minimal anchorage loss.

scholarly journals Evaluation of Ilizarov technique in the treatment of open fractures of tibia

2020 ◽  
Vol 7 (11) ◽  
pp. 3570
Author(s):  
Debdulal Debnath ◽  
Jihadul Islam ◽  
Nazmul Huda ◽  
M. A. A. Shameem
Keyword(s):  
Operation Time ◽  
Sports Injury ◽  
Deep Infection ◽  
Open Fractures ◽  
Type I ◽  
Ilizarov Technique ◽  
Duration Of Treatment ◽  
Non Union ◽  
Medical College ◽  
Short Time

Background: Now a day, open fracture of tibia is a common occurrence in the orthopedic treatment arena. Fundamentally, open fractures of tibia are classified into type I, II, IIIA, IIIB and IIIC. The aim of this study was to evaluate the Ilizarov technique in the treatment of open fractures of tibia.Methods: This was an observational prospective study conducted in the Department of Orthopedic Surgery, Northern International Medical College& Hospital, Dhaka, Bangladesh during the period from January 2017 to December 2017. Thirty-six (36) patients with tibial fractures were selected as the study population. This study was approved by the ethical committee of the respective medical college.Results: Out of total 36 participants, 65% were males and 35% were female. In analyzing mode of injuries, we found the highest 80.56% participants were from road accidents followed by 11.11% from sports injury and rest only 8.33% from general falls. The duration of treatment with the fixator was 12-23 weeks (average 16 weeks). In our study total 36 cases were debrided on the same day and stabilized with Ilizarov ring faxator after a period of 5 to 12 days from the date of injury. The operation time ranged from 90 minutes to 120 minutes (Mean 102±4 minutes).  Conclusions: In this study no case developed deep infection, non-union or unacceptable mal-union. The construct through Ilizarov is stable and enables the patient to bear weight on the affected limb a short time after the surgery, even in cases of comminuted fractures.

scholarly journals Alpha amylase inhibitory activitv of some plant extracts with hyporrlycemic activity

2004 ◽  
Vol 72 (1) ◽  
pp. 25-33 ◽  
Author(s):  
Rawand S. Abu Soud ◽  
lmad I. Hamdan ◽  
Fatma U. Afifi
Keyword(s):  
Cinnamic Acid ◽  
Plant Extracts ◽  
Crude Extract ◽  
Inhibitory Activity ◽  
Folk Medicine ◽  
Aloe Vera ◽  
Hypoglycemic Activity ◽  
Alpha Amylase ◽  
Potential Mechanism ◽  
Cinnamic Acid Derivatives

Thirteen plant species which are claimed to have anti-diabetic activity (based on folk medicine and/or scientific reports) were tested for alpha amylase inhibitory activity. Two of the screened plants exhibited significant (more than 80%) alpha amylase inhibitory activity. lC50 of these plants was estimated based on the dried crude extract and found to be 0.08, and 0.2 mg/ml for Aloe vera and Paronychia argentea respectively. In A. vera the activity was most likely due to cinnamic acid derivatives. In P. argentea the activity was attributed to flavonoid components. These findings support the hypoglycemic activity of these species and give insight about the potential mechanism of their hypoglycemic activity.

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