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Abeer A. Abd El Aty - One of the best experts on this subject based on the ideXlab platform.
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Thermodynamics enhancement of Alternaria tenuissima KM651985 laccase by covalent coupling to polysaccharides and its applications.
International journal of biological macromolecules, 2018Co-Authors: Faten A. Mostafa, Abeer A. Abd El AtyAbstract:Abstract This study full filed in enhancement of catalytic, thermodynamics and storage stability of Alternaria tenuissima KM651985 laccase by conjugation to sodium periodate oxidized starch. The starch conjugated A. tenuissima KM651985 laccase was active over a wide range of temperatures and pHs with the highest activity at 60 °C and 4, respectively. The thermal stability of conjugated A. tenuissima KM651985 laccase was indicated by, high T1/2 values (half life) 1076.16, 382.42 and 191.23 min at 50, 60 and 70 °C, respectively, low Kd (denaturation rate constant) 6.44 × 10−4, 18.13 × 10−4 and 36.25 × 10−4 min−1 at the same temperatures, high D-values (decimal reduction time) 3575.56, 1270.61 and 635.38 min at the same temperatures. Also, the thermal stability of conjugated A. tenuissima KM651985 laccase was emphasized by high ΔHd (enthalpy), high ΔGd (free energy) and low ΔSd (entropy). The conjugated A. tenuissima KM651985 laccase showed high effectiveness in dyes decolorization of Remazol Brilliant Blue R (RBBR) and Malachite Green (MG). Moreover, the addition of conjugated A. tenuissima KM651985 laccase with hemicellulolytic enzymes cocktail improved the saccharification of corn cobs, rice straw, corn cobs leaves and water hyacinth with the highest reducing sugar production 847.44 ± 19.17 mg from corn cops.
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Covalent immobilization of Alternaria tenuissima KM651985 laccase and some applied aspects
Biocatalysis and Agricultural Biotechnology, 2017Co-Authors: Abeer A. Abd El Aty, Faten A. Mostafa, Mohamed E. Hassan, Eman R. Hamed, Mona A. EsawyAbstract:Abstract Alternaria tenuissima KM651985 laccase was immobilized in Ca2+(AlgChG) beads with 93% immobilization yield. Optimum temperature for the free enzyme was 60 °C while the immobilized form showed a broad optimum temperature from 40 to 60 °C. The optimum pH was shifted from 4 to 5 for the free and immobilized enzyme, respectively. The immobilization process improved the enzyme thermal stability to great instant. The immobilized form could be reused for 19 times with 68% loss. Shelf stability reported that free and immobilized enzyme kept 61% and 84% of their original activities for 42 days, respectively. Some kinetic studies were achieved such as km, Vmax, and EA. The catalytic activity of immobilized laccase was also demonstrated by decolorization of two reactive dyes (Congo red dye and Crystal violet dye) and it's efficiently in reversed toxicity of two dyes on wheat seeds germination. Our result recommended A. tenuissima KM651985 laccase to be used in industrial scale.
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Induction and enhancement of the novel marine-derived Alternaria tenuissima KM651985 laccase enzyme using response surface methodology: Application to Azo and Triphenylmethane dyes decolorization -
journal of applied pharmaceutical science, 2016Co-Authors: Abeer A. Abd El Aty, Eman R. Hamed, Ahmed A. El-beih, Ahmed I. El-diwanyAbstract:In our search for a laccase producer from unconventional sources, the marine derived fungus Alternaria tenuissima KM651985 was isolated from decayed wood. It was identified on the basis of morphological and molecular taxonomy and got the Genbank accession number KM651985. Two statistical experimental designs were employed to enhance laccase production. At first, a two level Plackett–Burman design was employed to screen the medium constituents and inducers that significantly affect the enzyme production. Second experiment was important for optimization of the most effective constituents and inducers using central composite design. Applying the above methods revealed that guaiacol (2 mM), copper sulphate (3 mM) and wheat bran (46.82 g/l) were the most effective factors affecting laccase production. A maximal enzyme activity of 91.84 U/ml was more than 6.33-folds the activity obtained using the basal medium. Application of A. tenuissima KM651985 culture medium containing laccase to decolorize two structurally different synthetic dyes was done successfully. This is the first report on the statistical optimization of the marine-derived A. tenuissima KM651985 laccase enzyme and its applications for dyes decolorization.
Faten A. Mostafa - One of the best experts on this subject based on the ideXlab platform.
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Thermodynamics enhancement of Alternaria tenuissima KM651985 laccase by covalent coupling to polysaccharides and its applications.
International journal of biological macromolecules, 2018Co-Authors: Faten A. Mostafa, Abeer A. Abd El AtyAbstract:Abstract This study full filed in enhancement of catalytic, thermodynamics and storage stability of Alternaria tenuissima KM651985 laccase by conjugation to sodium periodate oxidized starch. The starch conjugated A. tenuissima KM651985 laccase was active over a wide range of temperatures and pHs with the highest activity at 60 °C and 4, respectively. The thermal stability of conjugated A. tenuissima KM651985 laccase was indicated by, high T1/2 values (half life) 1076.16, 382.42 and 191.23 min at 50, 60 and 70 °C, respectively, low Kd (denaturation rate constant) 6.44 × 10−4, 18.13 × 10−4 and 36.25 × 10−4 min−1 at the same temperatures, high D-values (decimal reduction time) 3575.56, 1270.61 and 635.38 min at the same temperatures. Also, the thermal stability of conjugated A. tenuissima KM651985 laccase was emphasized by high ΔHd (enthalpy), high ΔGd (free energy) and low ΔSd (entropy). The conjugated A. tenuissima KM651985 laccase showed high effectiveness in dyes decolorization of Remazol Brilliant Blue R (RBBR) and Malachite Green (MG). Moreover, the addition of conjugated A. tenuissima KM651985 laccase with hemicellulolytic enzymes cocktail improved the saccharification of corn cobs, rice straw, corn cobs leaves and water hyacinth with the highest reducing sugar production 847.44 ± 19.17 mg from corn cops.
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Covalent immobilization of Alternaria tenuissima KM651985 laccase and some applied aspects
Biocatalysis and Agricultural Biotechnology, 2017Co-Authors: Abeer A. Abd El Aty, Faten A. Mostafa, Mohamed E. Hassan, Eman R. Hamed, Mona A. EsawyAbstract:Abstract Alternaria tenuissima KM651985 laccase was immobilized in Ca2+(AlgChG) beads with 93% immobilization yield. Optimum temperature for the free enzyme was 60 °C while the immobilized form showed a broad optimum temperature from 40 to 60 °C. The optimum pH was shifted from 4 to 5 for the free and immobilized enzyme, respectively. The immobilization process improved the enzyme thermal stability to great instant. The immobilized form could be reused for 19 times with 68% loss. Shelf stability reported that free and immobilized enzyme kept 61% and 84% of their original activities for 42 days, respectively. Some kinetic studies were achieved such as km, Vmax, and EA. The catalytic activity of immobilized laccase was also demonstrated by decolorization of two reactive dyes (Congo red dye and Crystal violet dye) and it's efficiently in reversed toxicity of two dyes on wheat seeds germination. Our result recommended A. tenuissima KM651985 laccase to be used in industrial scale.
Mona A. Esawy - One of the best experts on this subject based on the ideXlab platform.
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Covalent immobilization of Alternaria tenuissima KM651985 laccase and some applied aspects
Biocatalysis and Agricultural Biotechnology, 2017Co-Authors: Abeer A. Abd El Aty, Faten A. Mostafa, Mohamed E. Hassan, Eman R. Hamed, Mona A. EsawyAbstract:Abstract Alternaria tenuissima KM651985 laccase was immobilized in Ca2+(AlgChG) beads with 93% immobilization yield. Optimum temperature for the free enzyme was 60 °C while the immobilized form showed a broad optimum temperature from 40 to 60 °C. The optimum pH was shifted from 4 to 5 for the free and immobilized enzyme, respectively. The immobilization process improved the enzyme thermal stability to great instant. The immobilized form could be reused for 19 times with 68% loss. Shelf stability reported that free and immobilized enzyme kept 61% and 84% of their original activities for 42 days, respectively. Some kinetic studies were achieved such as km, Vmax, and EA. The catalytic activity of immobilized laccase was also demonstrated by decolorization of two reactive dyes (Congo red dye and Crystal violet dye) and it's efficiently in reversed toxicity of two dyes on wheat seeds germination. Our result recommended A. tenuissima KM651985 laccase to be used in industrial scale.
Cheng Wang - One of the best experts on this subject based on the ideXlab platform.
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metabolic profiling on Alternaria toxins and components of xinjiang jujubes incubated with pathogenic Alternaria alternata and Alternaria tenuissima via orbitrap high resolution mass spectrometry
Journal of Agricultural and Food Chemistry, 2017Co-Authors: Yingying Fan, Yanglan Tan, Ye Tian, Na Liu, Lan Wang, Duoyong Zhao, Cheng WangAbstract:Xinjiang jujubes (Zizyphus rhamnaceae) are important agro-economical foods with the highest planting area and yields in China; however, black spot disease and contaminated Alternaria toxins have unfortunately caused a decline or loss of jujube nutritional quality in recent years. In this study, we used ultrahigh-performance liquid chromatography coupled to Orbitrap high-resolution mass spectrometry to profile both Alternaria toxins and components in three representative Xinjiang jujubes, Hami Huang, Hetian Jun, and Ruoqiang Hui. Before liquid chromatography–mass spectrometry analysis, jujubes were inoculated with two main pathogens of Alternaria alternata (Aa) and Alternaria tenuissima (At). Different combinations of jujube varieties with pathogenic isolates display different metabolic profiles, as expected. Moreover, four major Alternaria toxins, alternariol, alternariol monomethyl ether, altenuene, and tenuazonic acid, were detected in all samples. The inoculation of both pathogens significantly decreas...
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Metabolic Profiling on Alternaria Toxins and Components of Xinjiang Jujubes Incubated with Pathogenic Alternaria alternata and Alternaria tenuissima via Orbitrap High-Resolution Mass Spectrometry
2017Co-Authors: Yingying Fan, Yanglan Tan, Ye Tian, Na Liu, Lan Wang, Duoyong Zhao, Cheng WangAbstract:Xinjiang jujubes (Zizyphus rhamnaceae) are important agro-economical foods with the highest planting area and yields in China; however, black spot disease and contaminated Alternaria toxins have unfortunately caused a decline or loss of jujube nutritional quality in recent years. In this study, we used ultrahigh-performance liquid chromatography coupled to Orbitrap high-resolution mass spectrometry to profile both Alternaria toxins and components in three representative Xinjiang jujubes, Hami Huang, Hetian Jun, and Ruoqiang Hui. Before liquid chromatography–mass spectrometry analysis, jujubes were inoculated with two main pathogens of Alternaria alternata (Aa) and Alternaria tenuissima (At). Different combinations of jujube varieties with pathogenic isolates display different metabolic profiles, as expected. Moreover, four major Alternaria toxins, alternariol, alternariol monomethyl ether, altenuene, and tenuazonic acid, were detected in all samples. The inoculation of both pathogens significantly decreased the levels of nutrients and metabolites in jujube, including four saponins, three organic acids, and three alkaloids, whereas it increased the level of several glycerol phosphates. The flavonoid profiles are diverse. Lastly, inoculation of Aa changes more metabolites in jujubes than At. Our data provide insights to better understand the detrimental contamination of Alternaria pathogens in Xinjiang jujubes and improve food safety of jujubes
Mohamed Z. M. Salem - One of the best experts on this subject based on the ideXlab platform.
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Evaluation of the Antifungal Activity of Treated Acacia saligna Wood with Paraloid B-72/TiO2 Nanocomposites Against the Growth of Alternaria tenuissima, Trichoderma harzianum, and Fusarium culmorum
Bioresources, 2017Co-Authors: Mohamed Z. M. Salem, Maisa M. A. Mansour, Wael S. Mohamed, Hayssam M. Ali, Ashraf A. HatamlehAbstract:Acacia saligna wood was impregnated with 5% and 10% concentrations of Paraloid B-72/TiO2 nanocomposites using a soaking technique and evaluated for their antifungal activity against the growth of three molds in vitro, namely, Alternaria tenuissima, Trichoderma harzianum, and Fusarium culmorum. The Titanium (Ti) element peak of 0.14% and 0.23%, was found in the A. saligna wood treated with Paraloid B-72/TiO2 nanocomposites at 5% and 10%, respectively. Consolidant polymer Paraloid B-72 mixed with TiO2 nanocomposites at 5% and 10% showed antifungal activity against the three studied molds, while the linear growth of the studied molds reached the maximum in the control and Paraloid B-72 treatments. The results concluded that using synthesized Paraloid B-72/TiO2 nanocomposite could be considered as a new agent in the wood preservation field by prevention of mold fungal growth over the wood surfaces.
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evaluation of the antifungal activity of treated acacia saligna wood with paraloid b 72 tio2 nanocomposites against the growth of Alternaria tenuissima trichoderma harzianum and fusarium culmorum
Bioresources, 2017Co-Authors: Mohamed Z. M. Salem, Maisa M. A. Mansour, Wael S. Mohamed, Hayssam M. Ali, Ashraf A. HatamlehAbstract:Acacia saligna wood was impregnated with 5% and 10% concentrations of Paraloid B-72/TiO2 nanocomposites using a soaking technique and evaluated for their antifungal activity against the growth of three molds in vitro, namely, Alternaria tenuissima, Trichoderma harzianum, and Fusarium culmorum. The Titanium (Ti) element peak of 0.14% and 0.23%, was found in the A. saligna wood treated with Paraloid B-72/TiO2 nanocomposites at 5% and 10%, respectively. Consolidant polymer Paraloid B-72 mixed with TiO2 nanocomposites at 5% and 10% showed antifungal activity against the three studied molds, while the linear growth of the studied molds reached the maximum in the control and Paraloid B-72 treatments. The results concluded that using synthesized Paraloid B-72/TiO2 nanocomposite could be considered as a new agent in the wood preservation field by prevention of mold fungal growth over the wood surfaces.
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Comparative Evaluation of Some Woody Tree Methanolic Extracts and Paraloid B-72 against Phytopathogenic Mold Fungi Alternaria tenuissima and Fusarium culmorum
BioResources, 2015Co-Authors: Maisa M. A. Mansour, Ahmed Abdel-megeed, Ramadan A. Nasser, Mohamed Z. M. SalemAbstract:Natural compounds from certain timber trees are highly valued and recommended to protect wood and wood products against mold fungi. This study highlighted the use of some natural extracts and Paraloid B-72 against the growth of two mold fungi, namely Alternaria tenuissima and Fusarium culmorum. From the in vitro experiment, the methanol extracts of Callistemon viminalis bark were effective against the growth of F. culmorum, as were Magnolia grandiflora leaves against A. tenuissima. Environmental scanning electron microscopy (ESEM) and electron dispersive X-ray spectroscopy (EDX) analysis of treated Acacia saligna wood with the two fungi and Paraloid B-72 demonstrated the clear hyphal growth of F. culmorum and A. tenuissima and changes in elemental chemical composition. After three months, no fungal growth on the wood surface treated with the methanol extract of M. pomifera bark was found. After three months of treating wood with Paraloid B-72 at 5% and 10%, the mold growth was visible. Almost all of the wood treated with methanol extracts showed growth of the A. tenuissima hypha, as well as some contamination by other microorganisms, except for the wood treated with the methanol extract of M. pomifera bark.