Modelling of growth kinetics of isolated Pseudomonas sp. and optimisation of parameters for enhancement of xanthine oxidoreductase production by statistical design of experiments
01 Mar 2019-Journal of Environmental Science and Health Part A-toxic\/hazardous Substances & Environmental Engineering (Taylor & Francis)-Vol. 54, Iss: 1, pp 65-78
TL;DR: The effects of S0, pH and temperature were studied by Box-Behnken experimental design to evaluate the interactive effects of the significant variables influencing XOR production by CEBP1 and validated the second order polynomial model for the enzyme production.
Abstract: This report presents the substrate inhibitory effect of xanthine (XN) on microbial growth and optimisation of effective parameters to achieve high enzyme activity of xanthine oxidoreductase (XOR) t...
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15 May 2020
TL;DR: Overexpression of TSLP and JAK-STAT signaling pathway activation could reverse the effects of miR-142-5p on NASH, which might be a novel latent target for NASH therapy.
Abstract: This study aimed to figure out the underlying mechanism of miR-142-5p in the non-alcoholic steatohepatitis (NASH). Bioinformatics, luciferase assay and Western blot were performed. The NASH mouse model was established through feeding a high fat diet (HFD). Relative expressions of miR-142-5p, thymic stromal lymphopoietin (TSLP), inflammatory factors were detected by qRT-PCR. The injury level of liver was assessed via measurement of serum alanine aminotransferase (ALT) and serum aspartate aminotransferase (AST). H&E staining and Masson's trichrome staining examine the liver fatty degeneration and fibrosis. MiR-142-5p and TSLP were differentially expressed and JAK-STAT signaling pathway was activated in the NASH group. Luciferase assay identified that TSLP was the downstream target of miR-142-5p. Through overexpression of miR-142-5p, ALT and AST in serum were inhibited, pro-inflammatory factors, liver fatty degeneration and fibrosis in liver tissues were decreased, while anti-inflammatory factors were increased. Overexpression of TSLP and JAK-STAT signaling pathway activation could reverse the effects of miR-142-5p on NASH. Taken together, overexpression of miR-142-5p could attenuate NASH progression via inhibiting TSLP and JAK-STAT pathway. MiR-142-5p might be a novel latent target for NASH therapy.
13 citations
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...com 9076 AGING MiRNA reveals a biological function by affecting the expression of a target gene by incompletely binding to a target gene [23]....
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TL;DR: In this article, a novel polymeric nanocomposite modified transducer for quantification of p-Chloro-meta-Xylenol (PCMX) is presented.
9 citations
TL;DR: In this paper , a new design of biosensor based on polymeric nano(bio)composite has been proposed for the selective detection of xanthine to be used in the clinical analysis as well as food quality control.
7 citations
TL;DR: In this paper, the authors proposed a computational approach to calculate specific bacterial growth rate time-averaged over the entire sigmoidal log phase (including the decelerating phase) for incorporating the effect of metabolite-inhibition, in contrast to conventional studies where only the initial part (accelerating) of log phase was considered.
Abstract: A rigorous knowledge of the bacterial growth kinetics is essential for the scaling-up and optimization of biodegradation process conditions in a bioreactor. Although a great deal of literature is available on the modeling of bacterial growth kinetics considering the inhibition at high substrate-loading, the inhibition caused by toxic metabolic byproducts was not accounted in the bacterial growth kinetics. This work primarily aimed at developing a parametric bacterial growth model to account for metabolite inhibition, indicated by a decelerating log-phase growth, which was rarely discussed in the previous studies. An efficient azo-dye degrading bacterium (Bacillus subtilis MN372379) was isolated from the sludge-waste nearby a carpet-dyeing unit. The isolated bacterial strain was used to decolorize the simulated wastewater containing Congo red dye. This study proposed a computational approach to calculate specific bacterial growth rate time-averaged over the entire sigmoidal log phase (including the decelerating phase) for incorporating the effect of metabolite-inhibition, in contrast to the conventional studies where only the initial part (accelerating) of log phase was considered. The nature of metabolite inhibition was also determined and found to be non-competitive. Next, the computed time-averaged specific bacterial growth rate was incorporated into three substrate inhibition models to account for both, the metabolite and substrate inhibitions, and subsequently their kinetic parameters were also determined. Finally, the initial dye concentration and inoculum size were optimized to yield maximum dye utilization rate. This study paves the way for predicting bacterial growth kinetic with improved accuracy to enable a better optimization of bioreactors at the industrial scale.
3 citations
TL;DR: In this paper , a novel isolated phenol-resistant gram-negative bacterium, Pandoraea sp. strain BT102, is encapsulated in biopolymeric calcium alginate beads.
1 citations
References
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TL;DR: The production of acidic α-amylase by a novel acidophilic bacterium Bacillus acidicola TSAS1 was optimized in submerged fermentation using statistical approaches using central composite design of response surface methodology to achieve an overall 2.4 and 2.9-fold increase in enzyme production.
36 citations
TL;DR: The specific xanthine oxidase activity of goats' milk XOR was very much lower than that of bovine XOR, although NADH oxidase activities of XOR from the two sources were similar and the possible physiological significance of the low molybdenum content of the caprine milk enzyme and of its correspondingly low enzyme activity is discussed.
Abstract: Xanthine oxidoreductase (XOR) was purified from goats' milk. The u.v.–visible absorption spectrum was essentially identical to those of the corresponding bovine and human milk enzymes and showed an A280/A450 ratio of 5·20±0·12, indicating a high degree of purity. Like bovine and human milk XORs, enzyme purified from goats' milk showed a single band on SDS-PAGE corresponding to a subunit with approximate Mr 150000. On Western blotting, mouse monoclonal anti-human XOR antibody cross-reacted with purified caprine and bovine XORs. The specific xanthine oxidase activity of goats' milk XOR, however, was very much lower than that of bovine XOR, although NADH oxidase activities of XOR from the two sources were similar. In these respects, the caprine milk XOR mirrors the human milk enzyme, in which case the kinetic effects have previously been attributed to relatively low molybdenum content. The molybdenum content of goats' milk XOR also was shown to be relatively low, with 0·09 atoms Mo per subunit, compared with 0·55 atoms Mo per subunit for the bovine enzyme. A parallel purification of human milk XOR showed 0·03 atoms Mo per subunit. The possible physiological significance of the low molybdenum content of the caprine milk enzyme and of its correspondingly low enzymic activity is discussed.
35 citations
"Modelling of growth kinetics of iso..." refers background in this paper
...[2,10,41] Thus molecular weight of the subunits of xanthine oxidizing enzyme were nearly same even though source of enzyme varied....
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TL;DR: In this article, a novel nanobiocomposite for immobilization of xanthine oxidase (XO) was developed by incorporating functionalized MWCNT in nanogold doped poly(o-phenylenediamine) (PPD) (Au-PPD).
Abstract: A novel nanobiocomposite for immobilization of xanthine oxidase (XO) was developed by incorporating functionalized MWCNT in nanogold doped poly(o-phenylenediamine) (PPD) (Au–PPD) film on glassy carbon electrode (GCE) for selective and sensitive detection of xanthine in real samples e.g. blood, urine, fish. Stable colloid of o-phenylenediamine (OPD) and HAuCl4 in acidic environment was electropolymerized on working electrode (GCE) to form an ultrathin film of AuNP–PPD which possessed permselectivity and no interference against electroactive species such as ascorbic acid and uric acid. Spectrophotometric and microscopic analysis confirmed the doping behaviour of AuNP. Electrodeposition of carboxylated MWCNT onto the Au–PPD film increased conductivity, sensitivity and also facilitated a microenvironment to entrap XO enzyme by covalent bonding, enhancing storage stability. The conductive nature of the electrode after every step of modification was investigated by electrochemical impedance spectroscopy. High Imax/Kmap value was achieved by the XO/fMWCNT/Au–PPD modified electrode. Oxidation of xanthine on this modified electrode was diffusion-controlled involving two electrons in the rate-determining step with a transfer coefficient (α) of about 0.596. Differential pulse voltammetric study of XO/fMWCNT/Au–PPD/GCE exhibited good analytical characteristics e.g. low detection limit (12 nM) (S/N = 3), a wide linear range of 0.01–300 μM (R2 = 0.994), good sensitivity (14.03 μA μM−1 cm−2), fast response (6 s) at anodic potential of +0.625 V vs. Ag/AgCl (pH 7.0). It retained 91% of its initial activity even after 210 times of use over a period of 4 months when stored at 4 °C. The applicability of the xanthine biosensor was tested by performing reproducibility, repeatability and interference study on real samples.
33 citations
"Modelling of growth kinetics of iso..." refers background in this paper
...Quantification of XN and HX is useful to detect freshness of fish/meat derivatives in food processing industries.([4]) XOR...
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TL;DR: Medium development for high level expression of human interferon gamma from Pichia pastoris was performed with the aid of statistical and nonlinear modeling techniques and Plackett-Burman screening revealed that medium components, gluconate, glycine, KH2PO4 and histidine, have a considerable impact on hIFN-γ production.
Abstract: Medium development for high level expression of human interferon gamma (hIFN-γ) from Pichia pastoris (GS115) was performed with the aid of statistical and nonlinear modeling techniques. In the initial screening, gluconate and glycine were found to be key carbon and nitrogen sources, showing significant effect on production of hIFN-γ. Plackett-Burman screening revealed that medium components., gluconate, glycine, KH2PO4 and histidine, have a considerable impact on hIFN-γ production. Optimization was further proceeded with Box-Behnken design followed by artificial neural network linked genetic algorithm (ANN-GA). The maximum production of hIFN-γ was found to be 28.48mg/L using Box-Behnken optimization (R2=0.98), whereas the ANN-GA based optimization had displayed a better production rate of 30.99mg/L (R2=0.98), with optimal concentration of gluconate=50 g/L, glycine=10.185 g/L, KH2PO4=35.912 g/L and histidine 0.264 g/L. The validation was carried out in batch bioreactor and unstructured kinetic models were adapted. The Luedeking-Piret (L-P) model showed production of hIFN-γ was mixed growth associated with the maximum production rate of 40mg/L of hIFN-γ production.
33 citations
TL;DR: The EPR features of the redox-active centers of P. putida XDH are very similar to those of eukaryotic XDHs/xanthine oxidases, suggesting that the environment of each center and their functionality are analogous in these enzymes.
30 citations
"Modelling of growth kinetics of iso..." refers background in this paper
...putida 86 was induced by hypoxanthine.([8]) Effect of pH, temperature on the specific growth rate of the selected isolated strain in shake flask bioreactor...
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