scholarly journals The Biocatalytic Degradation of Organic Dyes Using Laccase Immobilized Magnetic Nanoparticles

2021 ◽  
Vol 11 (17) ◽  
pp. 8216
Author(s):  
Norah Salem Alsaiari ◽  
Abdelfattah Amari ◽  
Khadijah Mohammedsaleh Katubi ◽  
Fatimah Mohammed Alzahrani ◽  
Hamed N. Harharah ◽  
...  
Keyword(s):  
Organic Dyes ◽  
Dye Degradation ◽  
Storage Period ◽  
Industrial Applications ◽  
Maximum Activity ◽  
Copper Ferrite ◽  
Fe3o4 Nanoparticle ◽  
Immobilized Laccase ◽  
Wide Ph Range ◽  
And Storage

Free laccase has limitations for its use in industrial applications that require laccase immobilization on proper support, to improve its catalytic activity. Herein, the nanoparticles of magnetic iron oxide (Fe3O4) and copper ferrite (CuFe2O4) were successfully used as support for the immobilization of free laccase, using glutaraldehyde as a cross-linker. The immobilization conditions of laccase on the surface of nanoparticles were optimized to reach the maximum activity of the immobilized enzyme. The synthesized free nanoparticles and the nanoparticle-immobilized laccase were characterized using different techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). CuFe2O4 nanoparticles, as support, enhanced laccase activity compared to free laccase and Fe3O4 nanoparticle-immobilized laccase that appeared during the study of pH, temperature, and storage stability on free and immobilized laccase. The CuFe2O4 and Fe3O4 nanoparticle-immobilized laccase showed superior activity in a wide pH range, temperature range, and storage period, up to 20 days at 4.0 °C, when compared to free laccase. Additionally, the synthesized nanobiocatalysts were examined and optimized for the biodegradation of the anionic dye Direct Red 23 (DR23). HPLC analysis was used to confirm the dye degradation. The reusability of immobilized laccases for the biodegradation of DR23 dye was investigated for up to six successive cycles, with a decolorization efficiency over 70.0%, which indicated good reusability and excellent stability.

scholarly journals Horseradish Peroxidase-Carrying Electrospun Nonwoven Fabrics for the Treatment of o-Methoxyphenol

2015 ◽  
Vol 2015 ◽  
pp. 1-6
Author(s):  
Chao Pan ◽  
Ran Ding ◽  
Li Dong ◽  
Jing Wang ◽  
Yucai Hu
Keyword(s):  
Horseradish Peroxidase ◽  
Storage Stability ◽  
Storage Period ◽  
Industrial Applications ◽  
Initial Activity ◽  
Nonwoven Fabrics ◽  
Base Stability ◽  
Phenolic Wastewater ◽  
20 Nm ◽  
And Storage

The carboxyl-functionalized polystyrene (poly(styrene-co-methacrylic acid), PSMAA) nanofibers with average diameters of 250 ± 20 nm was prepared by electrospinning. PSMAA nanofibrous membrane were employed for immobilization of horseradish peroxidase (HRP) enzyme on the fibrous surface by a chemical method. The parameters about immobilizing HRP on the PSMAA nanofibers were studied and the influence on the activity of the HRP is discussed. This study showed that soap-free emulsion method is an ideal technology to modify the polystyrene surface and ultimately achieve enzyme immobilization on electrospun PSMAA nanofibers surfaces. Compared with free HRP, the acid-base stability, thermal stability, and storage stability of HRP were increased after the immobilization. The immobilized HRP maintained about 60% of its initial activity during a 20-day storage period. However, the free HRP maintained only 40% of its initial activity. The removal percentages of o-methoxyphenol (OMP) reached 80.2% after 120 min for immobilized HRP. These results suggest that the proposed scheme for immobilization of HRP has potential in industrial applications for the treatment of phenolic wastewater.

scholarly journals The Influence Mechanism of Temperature and Storage Period on Polarization Properties of Poly (Vinylidene Fluoride–Trifluoroethylene) Ultrathin Films

Membranes ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 301
Author(s):  
Xingjia Li ◽  
Zhi Shi ◽  
Xiuli Zhang ◽  
Xiangjian Meng ◽  
Zhiqiang Huang ◽  
...  
Keyword(s):  
Ultrathin Films ◽  
Remanent Polarization ◽  
Vinylidene Fluoride ◽  
Storage Period ◽  
Testing Temperature ◽  
Fatigue Properties ◽  
Inhibition Mechanism ◽  
Poly Vinylidene Fluoride ◽  
High Level ◽  
And Storage

The effect of testing temperature and storage period on the polarization fatigue properties of poly (vinylidene fluoride-trifluoroethylene) (P(VDF–TrFE)) ultrathin film devices were investigated. The experimental results show that, even after stored in air for 150 days, the relative remanent polarization (Pr/Pr(0)) of P(VDF–TrFE) of ultrathin films can keep at a relatively high level of 0.80 at 25 °C and 0.70 at 60 °C. To account for this result, a hydrogen fluoride (HF) formation inhibition mechanism was proposed, which correlated the testing temperature and the storage period with the microstructure of P(VDF–TrFE) molecular chain. Moreover, a theoretical model was constructed to describe the polarization fatigue evolution of P(VDF–TrFE) samples.

scholarly journals Changes in Particle Size, Sedimentation, and Protein Microstructure of Ultra-High-Temperature Skim Milk Considering Plasmin Concentration and Storage Temperature

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2339
Author(s):  
So-Yul Yun ◽  
Jee-Young Imm
Keyword(s):  
Particle Size ◽  
High Temperature ◽  
Storage Temperature ◽  
Whey Proteins ◽  
Skim Milk ◽  
Storage Period ◽  
Sediment Analysis ◽  
Sediment Formation ◽  
And Storage ◽  
Ultra High Temperature

Age gelation is a major quality defect in ultra-high-temperature (UHT) pasteurized milk during extended storage. Changes in plasmin (PL)-induced sedimentation were investigated during storage (23 °C and 37 °C, four weeks) of UHT skim milk treated with PL (2.5, 10, and 15 U/L). The increase in particle size and broadening of the particle size distribution of samples during storage were dependent on the PL concentration, storage period, and storage temperature. Sediment analysis indicated that elevated storage temperature accelerated protein sedimentation. The initial PL concentration was positively correlated with the amount of protein sediment in samples stored at 23 °C for four weeks (r = 0.615; p < 0.01), whereas this correlation was negative in samples stored at 37 °C for the same time (r = −0.358; p < 0.01) due to extensive proteolysis. SDS-PAGE revealed that whey proteins remained soluble over storage at 23 °C for four weeks, but they mostly disappeared from the soluble phase of PL-added samples after two weeks’ storage at 37 °C. Transmission electron micrographs of PL-containing UHT skim milk during storage at different temperatures supported the trend of sediment analysis well. Based on the Fourier transform infrared spectra of UHT skim milk stored at 23 °C for three weeks, PL-induced particle size enlargement was due to protein aggregation and the formation of intermolecular β-sheet structures, which contributed to casein destabilization, leading to sediment formation.

Effects of hybrid, kernel maturity, and storage period on the bacterial community in high-moisture and rehydrated corn grain silages

2020 ◽  
Vol 43 (5) ◽  
pp. 126131 ◽  
Author(s):  
Paula de Almeida Carvalho-Estrada ◽  
Juliana Fernandes ◽  
Érica Benjamim da Silva ◽  
Polyana Tizioto ◽  
Solidete de Fátima Paziani ◽  
...  
Keyword(s):  
Bacterial Community ◽  
Storage Period ◽  
High Moisture ◽  
And Storage ◽  
Corn Grain ◽  
Hybrid Kernel

Impact of initial grain moisture, fumigation, and storage period on physicochemical characteristics of wheat in Pakistan

2022 ◽  
Author(s):  
Muhammad Akhlaq ◽  
Shinawar Waseem Ali ◽  
Ayesha Murtaza ◽  
Muhammad Arshad Javed ◽  
Aftab Ahmad Khan ◽  
...  
Keyword(s):  
Storage Period ◽  
Physicochemical Characteristics ◽  
Grain Moisture ◽  
And Storage

scholarly journals ANTIOXIDANT ENZYME ACTIVITY AND FRESH-CUT ARRACACHA QUALITY

2015 ◽  
Vol 39 (3) ◽  
pp. 276-282
Author(s):  
Hêmina Carla Vilela ◽  
Patrícia de Fátima Pereira Goulart ◽  
Kamila Rezende Dázio de Souza ◽  
Ana Carolina Vilas Boas ◽  
Jane Silva Roda ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Antioxidant Enzymes ◽  
Nutritional Value ◽  
Storage Period ◽  
Antioxidant Enzyme Activity ◽  
Useful Life ◽  
Fresh Cut ◽  
Processing Techniques ◽  
And Storage ◽  
Microbiological Aspects

The arracacha is an alternative of fresh-cut product; however it can be easily degraded after the processing techniques. The objective of this work was to evaluate the useful life of fresh-cut arracacha submitted to two types of cuts and storage, as well as to evaluate the activity of antioxidant enzymes. The roots were selected, sanitized and submitted to two cut types: cubed and grated. Then they were evaluated at 3 times: 0, 3 and 7 days. The cutting in cubes provided higher quality and lower SOD, CAT and APX activity. However, the grated product presented higher PG activity and lower PPO activity. The microbiological safety and the nutritional value were maintained in both cuts during the whole storage period. The useful life, regarding the physicochemical, nutritional and microbiological aspects, can be established at 7 days under refrigeration for fresh-cut arracacha.

Lithium iron phosphate (LiFePO4) as an effective activator for degradation of organic dyes in water in the presence of persulfate

RSC Advances ◽  
2015 ◽  
Vol 5 (115) ◽  
pp. 94694-94701 ◽  
Author(s):  
Xue-ming Lin ◽  
Yong-wen Ma ◽  
Yan Wang ◽  
Jin-quan Wan ◽  
Ze-yu Guan
Keyword(s):  
Lithium Iron Phosphate ◽  
Organic Dyes ◽  
Dye Degradation ◽  
Iron Phosphate ◽  
Sulfate Radicals ◽  
Effective Activator

LiFePO4 was synthesized and successfully applied for activation of persulfate to produce sulfate radicals for dye degradation.

EFFECTS OF AGING, FREEZING RATE, AND STORAGE PERIOD ON PALATABILITY OF BROILERS

1945 ◽  
Vol 10 (1) ◽  
pp. 16-27 ◽  
Author(s):  
GEORGE FRANKLIN STEWART ◽  
HELEN LOUISE HANSON ◽  
BELLE LOWE ◽  
JOSEPH J. AUSTIN
Keyword(s):  
Storage Period ◽  
Freezing Rate ◽  
Effects Of Aging ◽  
And Storage

scholarly journals Microbiological Quality Analysis and Shelf Life Evaluation of Dahi Available in Kashmir

2020 ◽  
pp. 1-8
Author(s):  
Farhat Anjum ◽  
◽  
Rukhsana Rahman ◽  
Murtaza Gani ◽  
◽  
...  
Keyword(s):  
Microbiological Quality ◽  
Storage Period ◽  
Quality Analysis ◽  
Refrigerated Storage ◽  
Overall Acceptability ◽  
Titrable Acidity ◽  
Life Evaluation ◽  
Sensorial Attributes ◽  
Hedonic Scale ◽  
And Storage

Four commercially produced dahi samples were stored under 0°C, 10 °C and 20 °C temperatures subjected to microbiological examination, pH, titrable acidity and sensory attributes at various temperatures for a period of seven days. The results indicated an increase in microbial activity parameters and titrable acidity with increase in temperature and storage period. pH of dahi samples decreased with an increase in temperature and storage period indicating increase in acidity. The studies for microbiological studies shows increase in TPC along with the increase in days of storage. Similar case was found in Yeast and mould as well as in Coliform count. The TPC at refrigerated storage was observed as (1.69±0.58)106 to (5.0±0.68)106 while as at 20°C temperature it was observed as (1.5±0.35)106 to (4.5±0.12)10. Similarly the Yeast and mould count at refrigerated storage was observed as (1.0±0.92)106 while as at 20 °C temperature it was observed as ( 1.5±0.36)106 .The different samples of dahi were analysed for various sensorial attributes for their acceptance by using 9 point hedonic scale. The scores obtained with respect to colour, flavour, taste and aroma show good results and overall acceptability. Overall acceptability was also found to decrease significantly (p <.05) with increase in days of storage under refrigerated conditions. The results of the storage studies indicated the significant (p < .05) decrease in pH with the days of storage under different temperature conditions.

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