scholarly journals Preparation of Cross-Linked Enzyme Aggregates (CLEAs) of an Inulosucrase Mutant for the Enzymatic Synthesis of Inulin-Type Fructooligosaccharides

Catalysts ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 641 ◽  
Author(s):  
Thanapon Charoenwongpaiboon ◽  
Rath Pichyangkura ◽  
Robert A. Field ◽  
Manchumas Hengsakul Prousoontorn
Keyword(s):  
Enzymatic Synthesis ◽  
Biochemical Characterization ◽  
Lactobacillus Reuteri ◽  
Soluble Enzyme ◽  
Optimum Temperature ◽  
Optimum Conditions ◽  
Product Specificity ◽  
Product Characterization ◽  
Optimum Ph ◽  
Probiotic Activity

Fructooligosaccharides are well-known carbohydrate molecules that exhibit good probiotic activity and are widely used as sweeteners. Inulin-type fructooligosaccharides (IFOs) can be synthesized from sucrose using inulosucrase. In this study, cross-linked enzyme aggregates (CLEAs) of Lactobacillus reuteri 121 inulosucrase (R483A-LrInu) were prepared and used as a biocatalyst for IFOs production. Under optimum conditions, R483A-LrInu CLEAs retained 42% of original inulosucrase activity. Biochemical characterization demonstrated that the optimum pH of inulosucrase changed from 5 to 4 after immobilization, while the optimum temperature was unchanged. Furthermore, the pH stability and thermostability of the R483A-LrInu CLEAs was significantly improved. IFOs product characterization indicated that the product specificity of the enzyme was impacted by CLEA generation, producing a narrower range of IFOs than the soluble enzyme. In addition, the R483A-LrInu CLEAs showed operational stability in the batch synthesis of IFOs.

scholarly journals Preparation of Laccase Immobilized Cryogels and Usage for Decolorization

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Murat Uygun
Keyword(s):  
Glycidyl Methacrylate ◽  
Kinetic Properties ◽  
Optimum Temperature ◽  
Optimum Conditions ◽  
Immobilized Laccase ◽  
Optimum Ph ◽  
Edx Analyses ◽  
Swelling Studies ◽  
Laccase Enzyme ◽  
Thermal Stability Of

Poly(methyl methacrylate-co-glycidyl methacrylate) (poly(MMA-co-GMA)) cryogels were synthesized by radical cryopolymerization technique. Then, laccase enzyme was covalently attached to the cryogel and characterized by using swelling studies and SEM and EDX analyses. Kinetic properties and optimum conditions of the immobilized and free laccase were studied and it was found that of the immobilized laccase was lower than that of free laccase. of the immobilized laccase was increased upon immobilization. Optimum pH was found to be 4.0 for each type of laccase, while optimum temperature was shifted to the warmer region after the immobilization. It was also found that thermal stability of the immobilized laccase was higher than that of free laccase. Immobilized laccase could be used for 10 times successive reuse with no significant decrease in its activity. Also, these laccase immobilized cryogels were successfully used for the decolorization of seven different dyes.

scholarly journals Decolorization of textile dyes by partially purified Pleurotus ostreatus laccase

2014 ◽  
Vol 8 (3) ◽  
pp. 64-69
Author(s):  
Shamam saady Abdulredha ◽  
Abdulkareem jasim Hashim ◽  
Abduljabar Abas Ali ◽  
Batool Imran Dheeb
Keyword(s):  
Solid State ◽  
Pleurotus Ostreatus ◽  
Specific Activity ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Textile Dyes ◽  
Optimum Temperature ◽  
Optimum Conditions ◽  
Optimum Ph ◽  
Ph Range

Pleurotus ostreatus produced 2.93 U/mg of laccase in solid state fermentation (SSF) using barley bran as substrate under optimum conditions. The optimum SSF conditions were: pH 6.5; temperature, 25Cº; inoculums size 3.5 mm and moisture content, 1:1.5 w/v. Laccase was partially purified 8.29 fold with specific activity 17.5 U/mg by ion exchange chromatography after curd enzyme concentrated by dialysis against the solid sucrose. Partially purified laccase had an optimum pH of 6.5 and was stable in the pH range from 6.5 to 7.5. The optimum temperature was 45 Cº and it displayed considerable stability within the range 15 to 45 Cº with 1h incubation as well as The ability of partial purified laccase to decolorize of textile dyes showed that the blue H3R dye was completely decolorized in all concentrations within first min while yellow FG and red 3B dyes were decolorized in different percentage.

Immobilization and Characterization of Tannase and its Haze-removing

2009 ◽  
Vol 15 (6) ◽  
pp. 545-552 ◽  
Author(s):  
Erzheng Su ◽  
Tao Xia ◽  
Liping Gao ◽  
Qianying Dai ◽  
Zhengzhu Zhang
Keyword(s):  
Kinetic Parameter ◽  
High Activity ◽  
Green Tea ◽  
Storage Stability ◽  
Residual Activity ◽  
Black Tea ◽  
Optimum Temperature ◽  
Oolong Tea ◽  
Optimum Ph

Tannase was effectively immobilized on alginate by the method of crosslinking-entrapment-crosslinking with a high activity recovery of 76.6%. The properties of immobilized tannase were investigated. Its optimum temperature was determined to be 35 ° C, decreasing 10 °C compared with that of free enzyme, whereas the optimum pH of 5.0 did not change. The thermal and pH stabilities of immobilized tannase increased to some degree. The kinetic parameter, Km, for immobilized tannase was estimated to be 11.6 × 10-4 mol/L. Fe2+ and Mn2+ could activate the activity of immobilized tannase. The immobilized tannase was also applied to treat the tea beverage to investigate its haze-removing effect. The content of non-estern catechins in green tea, black tea and oolong tea increased by 52.17%, 12.94% and 8.83%, respectively. The content of estern catechins in green tea, oolong tea and black tea decreased by 20.0%, 16.68% and 5.04%, respectively. The anti-sediment effect of green tea infusion treated with immobilized tannase was significantly increased. The storage stability and reusability of the immobilized tannase were improved greatly, with 72.5% activity retention after stored for 42 days and 86.9% residual activity after repeatedly used for 30 times.

scholarly journals Properties of a new fungal b-galactosidase with potential application in the dairy industry

1999 ◽  
Vol 30 (3) ◽  
pp. 265-271 ◽  
Author(s):  
Rubens Cruz ◽  
Vinícius D'Arcádia Cruz ◽  
Juliana Gisele Belote ◽  
Marcelo de Oliveira Khenayfes ◽  
Claudia Dorta ◽  
...  
Keyword(s):  
Hydrolytic Activity ◽  
Industrial Applications ◽  
Transferase Activity ◽  
Optimum Temperature ◽  
Milk Whey ◽  
Beneficial Effects ◽  
Optimum Ph ◽  
Semi Solid ◽  
Good Productivity ◽  
Hydrolysis Of

<FONT FACE="Symbol">b</font>-Galactosidase or <FONT FACE="Symbol">b</font>-D-galactoside-galactohydrolase (EC. 3.2.1.23) is an important enzyme industrially used for the hydrolysis of lactose from milk and milk whey for several applications. Lately, the importance of this enzyme was enhanced by its galactosyltransferase activity, which is responsible for the synthesis of transgalactosylated oligosaccharides (TOS) that act as functional foods, with several beneficial effects on consumers. Penicillium simplicissimum, a strain isolated from soil, when grown in semi-solid medium showed good productivity of <FONT FACE="Symbol">b</font>-galactosidase with galactosyltransferase activity. The optimum pH for hydrolysis was in the 4.04.6 range and the optimum pH for galactosyltransferase activity was in the 6.07.0 range. The optimum temperature for hydrolysis and transferase activity was 55-60°C and 50°C, respectively, and the enzyme showed high thermostability for the hydrolytic activity. The enzyme showed a potential for several industrial applications such as removal of 67% of the lactose from milk and 84% of the lactose from milk whey when incubated at their original pH (4.5 and 6.34, respectively) under optimum temperature conditions. When incubated with a 40% lactose solution in 150 mM McIlvaine buffer, pH 4.5, at 55°C the enzyme converted 86.5% of the lactose to its component monosaccharides. When incubated with a 60% lactose solution in the same buffer but at pH 6.5 and 50°C, the enzyme can synthetize up to 30.5% TOS, with 39.5% lactose and 30% monosaccharides remaining in the preparation.

scholarly journals Optimal Conditions For Production Acidic D-Xylanase By Aspergillus niger in Submerged Fermentation

2011 ◽  
Vol 5 (3) ◽  
pp. 14-21
Author(s):  
Muhamed Omar Abdulatif ◽  
Hyder H. Assmaeel ◽  
Raghad kadhim Obeid ◽  
Ayat Adnan Abbas
Keyword(s):  
Aspergillus Niger ◽  
Rice Husk ◽  
Enzyme Production ◽  
Inoculum Size ◽  
Optimal Conditions ◽  
Optimum Conditions ◽  
Xylanase Production ◽  
Primary Isolation ◽  
Optimum Ph ◽  
Optimum Period

he Xylanase producing strain Aspergillus niger was isolated from soil on potato dextrose agar in the presence of xylan as its first substrate for primary isolation, and then grown under liquid medium fermentation in the presence of crude xylan (rice husk) to produce D-Xylanase. the optimum conditions were determined as follows: the Optimum pH for xylanase production was found pH 5.0, xylanase was induced by xylan (rice husk) 0.1% and the production was (61.221 U/ml) and nitrogen source Yeast extract recorded highest enzyme production( 89.71 U/ml), and repressed by carbon source xylose the highest enzyme production (88.69 U/ml). The optimum temperature was 40°с for xylanase production was (35.15 U/ml), the optimum period after 7 days of incubation was (52.33 U/ml) ,the optimum substrate concentration 0.1% was (45.95 U/ml), and the optimum inoculum size was 1 x 106 (spore /ml) recorded (57.19 U/ml ).

scholarly journals Characterization of Biosynthetic Enzymes for Ectoine as a Compatible Solute in a Moderately Halophilic Eubacterium, Halomonas elongata

1999 ◽  
Vol 181 (1) ◽  
pp. 91-99 ◽  
Author(s):  
Hisayo Ono ◽  
Kazuhisa Sawada ◽  
Nonpanga Khunajakr ◽  
Tao Tao ◽  
Mihoko Yamamoto ◽  
...  
Keyword(s):  
Molecular Mass ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Apparent Molecular Mass ◽  
Optimum Temperature ◽  
Sds Page ◽  
Halomonas Elongata ◽  
Optimum Ph

ABSTRACT 1,4,5,6-Tetrahydro-2-methyl-4-pyrimidinecarboxylic acid (ectoine) is an excellent osmoprotectant. The biosynthetic pathway of ectoine from aspartic β-semialdehyde (ASA), in Halomonas elongata, was elucidated by purification and characterization of each enzyme involved. 2,4-Diaminobutyrate (DABA) aminotransferase catalyzed reversively the first step of the pathway, conversion of ASA to DABA by transamination with l-glutamate. This enzyme required pyridoxal 5′-phosphate and potassium ions for its activity and stability. The gel filtration estimated an apparent molecular mass of 260 kDa, whereas molecular mass measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was 44 kDa. This enzyme exhibited an optimum pH of 8.6 and an optimum temperature of 25°C and had Km s of 9.1 mM forl-glutamate and 4.5 mM for dl-ASA. DABA acetyltransferase catalyzed acetylation of DABA to γ-N-acetyl-α,γ-diaminobutyric acid (ADABA) with acetyl coenzyme A and exhibited an optimum pH of 8.2 and an optimum temperature of 20°C in the presence of 0.4 M NaCl. The molecular mass was 45 kDa by gel filtration. Ectoine synthase catalyzed circularization of ADABA to ectoine and exhibited an optimum pH of 8.5 to 9.0 and an optimum temperature of 15°C in the presence of 0.5 M NaCl. This enzyme had an apparent molecular mass of 19 kDa by SDS-PAGE and a Km of 8.4 mM in the presence of 0.77 M NaCl. DABA acetyltransferase and ectoine synthase were stabilized in the presence of NaCl (>2 M) and DABA (100 mM) at temperatures below 30°C.

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.

scholarly journals Lipase-catalyzed transesterification of rendering plant fat – Short Communication

2010 ◽  
Vol 56 (No. 3) ◽  
pp. 122-125 ◽  
Author(s):  
A. Prošková ◽  
Z. Kopicová ◽  
J. Kučera ◽  
L. Škarková
Keyword(s):  
Short Communication ◽  
Immobilized Enzyme ◽  
Immobilized Lipase ◽  
Covalent Bond ◽  
Novozym 435 ◽  
Optimum Temperature ◽  
Optimum Conditions ◽  
Soluble Lipase ◽  
Good Accordance ◽  
Higher Temperature

Soluble lipase (Lipozyme CALB L) was immobilized by covalent bond to chitosan pellets prepared from Aspergillus niger mycelium. This immobilized enzyme was compared with commercial immobilized lipase of the same origin (Novozym 435). Novozym 435 is also lipase CALB L commercially immobilized by sorption on poly-(methyl acrylate). Novozym 435 shows much higher conversion of rendering plant fat in methanol under optimum conditions, having, at the same time, lower optimum temperature and lower stability at higher temperature. Lipozyme CALB L immobilized on chitosan leads to a low conversion, regardless its higher thermal stability. Novozym 435 gives conversion of about 50% of theoretical value, which is in good accordance with basically catalyzed transesterification of rendering plant fat described elsewhere. Lipozyme CALB L immobilized on chitosan gives conversion of about 10% of theoretical value only. The use of Novozym 435 in two-step system (enzyme-acid) seems to be more convenient compared with traditional two-step system (base-acid)

scholarly journals Heterologous Expression of a Thermostable α-Glucosidase from Geobacillus sp. Strain HTA-462 by Escherichia coli and Its Potential Application for Isomaltose–Oligosaccharide Synthesis

Molecules ◽  
2019 ◽  
Vol 24 (7) ◽  
pp. 1413
Author(s):  
Fan Zhang ◽  
Weiyang Wang ◽  
Fatoumata Binta Maci Bah ◽  
Chengcheng Song ◽  
Yifa Zhou ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Enzymatic Synthesis ◽  
Bacillus Stearothermophilus ◽  
Maximal Activity ◽  
Oligosaccharide Synthesis ◽  
Optimum Temperature ◽  
Divalent Ions ◽  
Food Ingredients ◽  
Shake Flasks ◽  
Maltose Syrup

Isomaltose–oligosaccharides (IMOs), as food ingredients with prebiotic functionality, can be prepared via enzymatic synthesis using α-glucosidase. In the present study, the α-glucosidase (GSJ) from Geobacillus sp. strain HTA-462 was cloned and expressed in Escherichia coli BL21 (DE3). Recombinant GSJ was purified and biochemically characterized. The optimum temperature condition of the recombinant enzyme was 65 °C, and the half-life was 84 h at 60 °C, whereas the enzyme was active over the range of pH 6.0–10.0 with maximal activity at pH 7.0. The α-glucosidase activity in shake flasks reached 107.9 U/mL and using 4-Nitrophenyl β-D-glucopyranoside (pNPG) as substrate, the Km and Vmax values were 2.321 mM and 306.3 U/mg, respectively. The divalent ions Mn2+ and Ca2+ could improve GSJ activity by 32.1% and 13.8%. Moreover, the hydrolysis ability of recombinant α-glucosidase was almost the same as that of the commercial α-glucosidase (Bacillus stearothermophilus). In terms of the transglycosylation reaction, with 30% maltose syrup under the condition of 60 °C and pH 7.0, IMOs were synthesized with a conversion rate of 37%. These studies lay the basis for the industrial application of recombinant α-glucosidase.

Influence of Environmental Factors on Smallflower Morningglory (Jacquemontia tamnifolia) Germination and Growth

Weed Science ◽  
1987 ◽  
Vol 35 (4) ◽  
pp. 519-523 ◽  
Author(s):  
David R. Shaw ◽  
H. Randy Smith ◽  
A. Wayne Cole ◽  
Charles E. Snipes
Keyword(s):  
Environmental Factors ◽  
Optimum Temperature ◽  
Full Sunlight ◽  
Optimum Ph ◽  
Germination And Growth

The optimum pH for germination of smallflower morningglory (Jacquemontia tamnifolia(L.) Griseb. # IAQTA] seed was 8.0. A scarification time of 25 to 60 s using a drum scarifier with medium grit provided the best germination, and the optimum temperature for germination was 35 to 40C. However, the optimum temperature for growth was 25 to 35C, with reductions in growth occurring above or below this range. Emergence after 14 days was 81 and 49% at planting depths of 1.5 and 10 cm, respectively. Shade levels of 30 to 92% reduced smallflower morningglory growth by 38 to 87% compared to plants grown in full sunlight.

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