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1.
Heliyon ; 10(13): e33391, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39035547

RESUMO

The integration of industry and education can be literally explained as the role of education in providing intellectual support and production services for the development of industries in a country or region, evolving from an auxiliary role in industrial development to a supporting role in industrial development. The government, enterprises, universities, and intermediaries are all the main bodies of industry education integration, and school enterprise cooperation is the core. The two basic functions of universities, namely "applied scientific research" and "social services", must be highlighted. How to strengthen the cultivation of applied talents and improve the quality of talent cultivation in universities is a problem that universities must face in their transformation. Strengthening school enterprise cooperation and promoting the integration of industry and education is an effective way to solve this problem. The development evaluation of school-enterprise cooperation from the perspective of collaborative education is a multiple-attribute group decision-making (MAGDM) problem. Recently, the Logarithmic TODIM (LogTODIM) and PROMETHEE technique was employed to put forward the MAGDM issues. The probabilistic linguistic term sets (PLTSs) are employed as a technique for characterizing uncertain information during the development evaluation of school-enterprise cooperation from the perspective of collaborative education. In this paper, the probabilistic linguistic LogTODIM-PROMETHEE (PL-LogTODIM-PROMETHEE) technique is constructed to put forward the MAGDM under PLTSs. The MEREC technique is employed to obtain the weight values under PLTSs. Finally, a numerical example for development evaluation of school-enterprise cooperation from the perspective of collaborative education is put forward to validate the LogTODIM-PROMETHEE technique.

2.
Int J Biol Macromol ; 245: 125533, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37355062

RESUMO

Recombinant INANE1 (rINANE1), a recombinant intracellular GDSL-type esterase from Aspergillus niger GZUF36, has high acetate substrate specificity. Here, rINANE1 was successfully immobilized on polydopamine (PDA)-modified magnetic ferric oxide nanoparticles (Fe3O4NPs) by adsorption-precipitation-cross-linking to obtain cross-linked enzyme aggregate (CLEA)-rINANE1-Fe3O4@PDA. Fe3O4, Fe3O4@PDA, and CLEA-rINANE1-Fe3O4@PDA were characterized by scanning electron microscopy, X-ray diffraction, vibrating-sample magnetometry, Fourier transform infrared (FTIR) spectroscopy, and zeta potential analysis. Upon immobilization, CLEA-rINANE1-Fe3O4@PDA, with a protein loading of 72.72 ± 1.01 mg/g, reached optimal activity recovery of 104.40 % ± 1.14 %. FTIR analysis showed that immobilization increased the relative content of ß-folding in rINANE1 by 12.25 % and reduced irregular curl by 4.16 %, rendering the structure more orderly. Specifically, under an alkaline condition (pH 10), CLEA-rINANE1-Fe3O4@PDA performed over 100 % of initial activity. The optimum temperature increased by 5 °C, and over 55 % of the initial activity was observed after 12 h at 55 °C. CLEA-rINANE1-Fe3O4@PDA showed over 40 % of its relative activity, whereas free rINANE1 showed <10 % in acetonitrile. In addition, the relative activity of CLEA-rINANE1-Fe3O4@PDA was retained at about 80 % after eight cycles and maintained at 109 % after 45 days. The PDA-modified magnetic ferrite nanoparticles exhibited excellent stability and recyclability, providing a new avenue for developing industrial biocatalysts.


Assuntos
Enzimas Imobilizadas , Nanopartículas de Magnetita , Enzimas Imobilizadas/química , Estabilidade Enzimática , Esterases/metabolismo , Aspergillus niger/metabolismo , Adsorção , Fenômenos Magnéticos , Concentração de Íons de Hidrogênio , Temperatura , Nanopartículas de Magnetita/química
3.
Food Chem X ; 17: 100570, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36845476

RESUMO

The antioxidant activity of Auricularia polytricha is associated tightly with its polysaccharide concentration, molar mass and architecture. This study aims to explore the differences in structural and physicochemical traits and oxidation resistances between the polysaccharides from fruit body (ABPs) and mycelial (IAPs) of Auricularia polytricha. The results showed that ABPs and IAPs were constituted by glucose, glucuronic acid, galactose and mannose. However, the molecular weight distribution of IAPs (3.22 × 104 Da (52.73%) and 1.95 × 106 Da (24.71%)) was wider than that of ABPs (5.4 × 106 Da (95.77%)). The shear-thinning performance and viscoelastic behavior of both IAPs and ABPs are representative. IAPs are scattered in sheets, with folds and holes, and have a triple helix structure. ABPs are compact in structure and clear in texture. The main functional groups and thermal stability of both polysaccharides were similar. Concerning the in-vitro oxidation resistance, both of the studied polysaccharides exhibited the potent potential to scavenge hydroxyl radicals (IC50 = 3.37 ± 0.32 and 6.56 ± 0.54 mg/mL, respectively) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals (IC50 = 0.89 ± 0.22 and 1.48 ± 0.63 mg/mL, respectively), as well as the moderate reduction power. In addition, IAPs and ABPs were both completely undigested in simulated contexts of saliva, small intestine and stomach, and the two polysaccharide types maintained high DPPH and hydroxyl radical scavenging activities. DDPH scavenging rate during digestion was positively correlated with uronic acid content. To conclude, this study suggests the potential of IAPs as an equivalent alternative to ABPs.

4.
Front Microbiol ; 13: 811275, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35185846

RESUMO

Yellow slurry water is a kind of nutrient-rich wastewater of tofu. Firstly, the medium of yellow slurry was optimized. Then, APP40, APP60, and APP80 were obtained by sedimentation with different concentration of ethanol (40, 60, and 80%). The physicochemical properties and primary structures of the three polysaccharides were studied by high performance anion exchange chromatography (HPAEC), high performance gel filtration chromatography (HPGFC), scanning electron microscope (SEM), atomic force microscope (AFM), and Fourier transform infrared (FT-IR) spectrometer. Finally, the effects of three polysaccharides on antioxidation activity were studied. According to the experimental optimization the results, the biomass and the production of Auricularia polytricha Polysaccharides (APPS) reached the peak, and they were 13.5 ± .655 and 9.42 ± .253 g/L (p < .05). The SEM and the AFM showed that the height of APP80 gradually increased from 31.1 to 46.7 nm and from APP40 to APP80. The particle size of APP80 increased, the pores decrease or even disappear, and the molecules begin to aggregate. The FT-IR spectrum analysis showed that the three polysaccharides possessed key functional groups. The carbohydrate content of APP40, APP60, and APP80 was 20.2, 34.25, and 31.73%. The molecular weights of APP40, APP60, and APP80 are 9.462 × 104, 8.742 × 104, and 8.091 × 104 Da, respectively. The three polysaccharides were composed of rhamnose, galactose, glucose, mannose, and xylose but with different molar ratio. APP80 showed strong reducing ability and scavenging activity of 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals through antioxidant activities evaluated in vitro. This study introduces a way for the effective use of yellow slurry water.

5.
Front Microbiol ; 13: 820539, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35211105

RESUMO

Predicting the number of microorganisms has excellent application in the food industry. It helps in predicting and managing the storage time and food safety. This study aimed to establish a new, simple, and effective model for predicting the number of microorganisms. The dimensional analysis model (DAM) was established based on dimensionless analysis and the Pi theorem. It was then applied to predict the number of Pseudomonas in Niuganba (NGB), a traditional Chinese fermented dry-cured beef, which was prepared and stored at 278 K, 283 K, and 288 K. Finally, the internal and external validation of the DAM was performed using six parameters including R 2, R 2 adj , root mean square error (RMSE), standard error of prediction (%SEP), A f , and B f . High R 2 and R 2 adj and low RMSE and %SEP values indicated that the DAM had high accuracy in predicting the number of microorganisms and the storage time of NGB samples. Both A f and B f values were close to 1. The correlation between the observed and predicted numbers of Pseudomonas was high. The study showed that the DAM was a simple, unified and effective model to predict the number of microorganisms and storage time.

6.
Front Microbiol ; 12: 633489, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776965

RESUMO

In this study, a sn-1, 3 extracellular lipases from Aspergillus niger GZUF36 (PEXANL1) was expressed in Pichia pastoris, characterized, and the predicted structural model was analyzed. The optimized culture conditions of P. pastoris showed that the highest lipase activity of 66.5 ± 1.4 U/mL (P < 0.05) could be attained with 1% methanol and 96 h induction time. The purified PEXANL1 exhibited the highest activity at pH 4.0 and 40°C temperature, and its original activity remained unaltered in the majority of the organic solvents (20% v/v concentration). Triton X-100, Tween 20, Tween 80, and SDS at a concentration of 0.01% (w/v) enhanced, and all the metal ions tested inhibited activity of purified PEXANL. The results of ultrasound-assisted PEXANL1 catalyzed synthesis of 1,3-diaglycerides showed that the content of 1,3-diglycerides was rapidly increased to 36.90% with 25 min of ultrasound duration (P < 0.05) and later decreased to 19.93% with 35 min of ultrasound duration. The modeled structure of PEXANL1 by comparative modeling showed α/ß hydrolase fold. Structural superposition and molecular docking results validated that Ser162, His274, and Asp217 residues of PEXANL1 were involved in the catalysis. Small-angle X-ray scattering analysis indicated the monomer properties of PEXANL1 in solution. The ab initio model of PEXANL1 overlapped with its modeling structure. This work presents a reliable structural model of A. niger lipase based on homology modeling and small-angle X-ray scattering. Besides, the data from this study will benefit the rational design of suitable crystalline lipase variants in the future.

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