Modeling the optimal condition for drying rumen contents using a solar greenhouse dryer

Two possible modes of action of exo-D-galacturonanase from carrot (E.C. 3.2.1.67) were investigated; this enzyme catalyses the sequential hydrolytic cleavage of pectants and oligogalacturonans by a terminal action from the nonreducing end of the molecule. The experiments indicate that the investigated exo-D-galacturonanase degrades these substrates by a predominantly multi-chain mechanism. Distribution of degradation products of oligomeric substrates (hexa- and pentagalacturonide) under an optimal condition for the action of the enzyme (pH and temperature) indicates that a multi-chain enzyme attack with a prevalent simple collision is involved. Results of the enzyme degradation kinetics are in a good agreement with the above-mentioned presumption.

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Expression and characterization of an α-glucosidase from Thermoanaerobacter ethanolicus JW200 with potential for industrial application

Biologia ◽

10.2478/s11756-009-0197-1 ◽

2009 ◽

Vol 64 (6) ◽

Cited By ~ 9

Author(s):

Yue-Hong Wang ◽

Yu Jiang ◽

Zuo-Ying Duan ◽

Wei-Lan Shao ◽

Hua-Zhong Li

Keyword(s):

Escherichia Coli ◽

Heat Shock ◽

Optimal Condition ◽

Industrial Application ◽

Conversion Rate ◽

Hydrolytic Activity ◽

Thermoanaerobacter Ethanolicus ◽

Transglycosylation Activity

AbstractIn this study, a new α-glucosidase gene from Thermoanaerobacter ethanolicus JW200 was cloned and expressed in Escherichia coli by a novel heat-shock vector pHsh. The recombinant α-glucosidase exhibited its maximum hydrolytic activity at 70°C and pH 5.0∼5.5. With p-nitrophenyl-α-D-glucoside as a substrate and under the optimal condition (70°C, pH 5.5), K m and V max of the enzyme was 1.72 mM and 39 U/mg, respectively. The purified α-glucosidase could hydrolyze oligosaccharides with both α-1,4 and α-1,6 linkages. The enzyme also had strong transglycosylation activity when maltose was used as sugar donor. The transglucosylation products towards maltose are isomaltose, maltotriose, panose, isomaltotriose and tetrasaccharides. The enzyme could convert 400 g/L maltose to oligosaccharides with a conversion rate of 52%, and 83% of the oligosaccharides formed were prebiotic isomaltooligosaccharides (containing isomaltose, panose and isomaltotriose).

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A Response Surface Methodology (RSM) Approach for Optimizing the Attenuation of Human IgE-Reactivity to β-Lactoglobulin (β-Lg) by Hydrostatic High Pressure Processing

Foods ◽

10.3390/foods10081741 ◽

2021 ◽

Vol 10 (8) ◽

pp. 1741

Author(s):

Xin Sun ◽

Jialing Vivien Chua ◽

Quynh Anh Le ◽

Francisco Trujillo ◽

Mi-Hwa Oh ◽

...

Keyword(s):

Response Surface Methodology ◽

Optimal Condition ◽

Response Surface ◽

High Pressure Processing ◽

Molecular Structures ◽

Holding Time ◽

P Value ◽

Molecular Change ◽

Ige Reactivity ◽

Β Lactoglobulin

The response surface methodology (RSM) and central composite design (CCD) technique were used to optimize the three key process parameters (i.e., pressure, temperature and holding time) of the high-hydrostatic-pressure (HHP) processing either standalone or combined with moderate thermal processing to modulate molecular structures of β-lactoglobulin (β-Lg) and α-lactalbumin (α-La) with reduced human IgE-reactivity. The RSM model derived for HHP-induced molecular changes of β-Lg determined immunochemically showed that temperature (temp), pressure (p2) and the interaction between temperature and time (t) had statistically significant effects (p < 0.05). The optimal condition defined as minimum (β-Lg specific) IgG-binding derived from the model was 505 MPa at 56 °C with a holding time of 102 min (R2 of 0.81 and p-value of 0.01). The validation carried at the optimal condition and its surrounding region showed that the model to be underestimating the β-Lg structure modification. The molecular change of β-Lg was directly correlated with HHP-induced dimerization in this study, which followed a quadratic equation. The β-Lg dimers also resulted in the undetectable human IgE-binding.

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Optimal regularity of stable solutions to nonlinear equations involving the p-Laplacian

Advances in Calculus of Variations ◽

10.1515/acv-2020-0055 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Xavier Cabré ◽

Pietro Miraglio ◽

Manel Sanchón

Keyword(s):

Dirichlet Problem ◽

Optimal Condition ◽

Bounded Domain ◽

Laplace Operator ◽

Nonlinear Equations ◽

Open Problem ◽

Optimal Range ◽

Optimal Regularity ◽

Smooth Bounded Domain ◽

Stable Solutions

AbstractWe consider the equation {-\Delta_{p}u=f(u)} in a smooth bounded domain of {\mathbb{R}^{n}}, where {\Delta_{p}} is the p-Laplace operator. Explicit examples of unbounded stable energy solutions are known if {n\geq p+\frac{4p}{p-1}}. Instead, when {n<p+\frac{4p}{p-1}}, stable solutions have been proved to be bounded only in the radial case or under strong assumptions on f. In this article we solve a long-standing open problem: we prove an interior {C^{\alpha}} bound for stable solutions which holds for every nonnegative {f\in C^{1}} whenever {p\geq 2} and the optimal condition {n<p+\frac{4p}{p-1}} holds. When {p\in(1,2)}, we obtain the same result under the nonsharp assumption {n<5p}. These interior estimates lead to the boundedness of stable and extremal solutions to the associated Dirichlet problem when the domain is strictly convex. Our work extends to the p-Laplacian some of the recent results of Figalli, Ros-Oton, Serra, and the first author for the classical Laplacian, which have established the regularity of stable solutions when {p=2} in the optimal range {n<10}.

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