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Carex spp. and Artemisia selengensis communities are typical renewal wetland plant communities at cutting slash of Populus deltoides. However, how rhizosphere microorganisms and soil factors interact during natural restoration in plant communities is unknown. Plots containing Carex spp. and Artemisia selengensis in the slash area were investigated, and the P. deltoides plantation area at a lake shore was sampled as a control. The results revealed that the richness and diversity indices of the fungal community in the Carex spp. community were higher than those in the A. selengensis and P. deltoides undergrowth communities. Ascomycota was the dominant phylum in the soil of Carex spp. community whereas Basidiomycota was the dominant phylum in the A. selengensis community. The richness and diversity indices of the rhizosphere bacterial community in the control were higher than those in communities of Carex spp. and A. Selengensis. Proteobacteria and Actinobacteria were the dominant phyla of the rhizosphere bacterial community in the control plot. Soil water content (WC), proportion of clay (CY), and nutrient content, as well as catalase activity (CAT) in the soil of Carex spp. community were the highest, whereas those in the control were the lowest. Conversely, the bulk density (BK) and proportion of gravel in the control plot were the highest. RDA found that the CY, organic matter (OM), ammonium nitrogen (AN) and nitrate nitrogen (NN) content in the soil were the key factors affecting the structure and composition of the rhizosphere microbial community.

To establish and apply the home nutrition care and follow-up management pattern for the treatment of patients with intestinal failure (IF).This retrospective study analyzed patients with IF who received nutrition nursing and follow-up management at the Clinical Nutrition Treatment Center of Jinling Hospital between January 2018 and April 2022. The changes in nutritional indicators and body compositions of patients before and after standardized management were recorded and compared.A total of 65 patients with IF were enrolled, with a mean age of 52.4±15.8 years and BMI of 17.9±2.7 kg/m2. Compared with before the application of home nutrition nursing and follow-up man-agement, nutritional indicators (Albumin, Prealbumin, and Hemoglobin) were improved significantly in IF patients after the standard management (p0.05, all). In addition, the body mass index (BMI), fat-free mass index (FFMI), and skeletal muscle mass index (SMI) were also significantly increased after standard management (p0.05, all).The establishment and application of home nutrition nursing and follow-up pattern could ensure the nutritional support effect and improve the nutritional status and body composition of patients with IF.

The sensing characteristics of irradiated fiber Bragg gratings (FBGs) and Fabry-Perot interferometers (FPIs) were investigated under a 2 MGy dose of gamma radiation. The study found that the pressure sensitivity of FP sensors after irradiation was stable, while the temperature sensitivity of FBG sensors was unstable, and both wavelengths displayed a shift. These findings offer the possibility for the application of FP pressure sensors in the gamma radiation environments, and FBG sensors require further research to be suitable for application in the nuclear radiation environments.

Cellobiose 2-epimerase (CE) is a promising industrial enzyme that can catalyze bioconversion of lactose to its high-value derivatives, namely epilactose and lactulose. A need exists in the dairy industry to catalyze lactose bioconversions at low temperatures to avoid microbial growth. We focused on the discovery of cold-active CE in this study. A genome mining method based on computational prediction was used to screen the potential genes encoding cold-active enzymes. The CE-encoding gene from Roseburia intestinalis, with a predicted high structural flexibility, was expressed heterologously in Escherichia coli. The catalytic property of the recombinant enzyme was extensively studied. The optimum temperature and pH of the enzyme were 45°C and 7.0, respectively. The specific activity of this enzyme to catalyze conversion of lactose to epilactose was measured to be 77.3 ± 1.6 U/mg. The kinetic parameters, including turnover number (kcat), Michaelis constant (Km), and catalytic efficiency (kcat/Km) using lactose as a substrate were 117.0 ± 7.7 s-1, 429.9 ± 57.3 mM, and 0.27 mM-1s-1, respectively. In situ production of epilactose was carried out at 8°C: 20.9% of 68.4 g/L lactose was converted into epilactose in 4 h using 0.02 mg/mL (1.5 U/mL, measured at 45°C) of recombinant enzyme. The enzyme discovered by this in silico method is suitable for low-temperature applications.

Lactose is a natural disaccharide obtained from the milk of most mammals and a waste product of cheese and casein manufacturing. Over the past decades, lactose in whey has increasingly been promoted as an important resource, and an increasing number of significant advances have been made to investigate its healthy and functional properties. Lactose can be biotransformed into many kinds of derivatives, including galacto-oligosaccharides, epilactose, lactulose, lactosucrose, and D-tagatose. Biological efficiency and safety are critical for the enzymatic production of lactose derivatives from lactose. These lactose derivatives show a range of prominent physiological features and effects, such as prebiotic properties, indigestibility, and obesity prevention, which can be utilized in the pharmaceutical, health, and food industries. In this review, we present the properties and physiological effects of lactose derivatives, detailing their biological production by various enzymes and their applications in dairy products, especially directly in the milk industry.

Rhodiola species are edible medicinal plants, which have been traditionally used in both Asia and Europe as an adaptogen, a tonic, an anti-depressant and anti-inflammatory supplement. However, whether it presents a therapeutic effect on colitis or not remains unknown. The aim of this study is to investigate the protective effect of a Rhodiola crenulata extract (RCE) on mice with DSS-induced colitis. RCE significantly alleviated the pathological abnormalities in colitic mice, including the correspondingly increased colon length, ameliorated colonic injury and reduced pro-inflammatory factors. The protective effect was similar to that of the positive control, 5-aminosalicylic acid. The DSS-induced epithelial apoptosis and maintained intestinal barrier function were attenuated by RCE through the upregulation of the level of tight junction proteins such as ZO-1 and occludin. Notably, RCE prevented gut dysbiosis in colitic mice by restoring the microbial richness and diversity, and decreasing the abundance of Proteobacteria phylum and opportunistic pathogenic Parasutterella and Staphylococcus, as well as increasing the abundance of beneficial microbes in Lactobacillus and Bifidobacterium, which were closely correlated with its protective effect against colitis. Meanwhile, chemical characterization of RCE was performed by UPLC-HR-MS to explain its material basis. A total of 63 compounds were identified, while the content of two bioactive ingredients (salidroside, 1.81%; rosavin, 0.034%) was determined.

The sensing characteristics of Fabry-Perot interferometers (FPIs) and fiber Bragg gratings (FBGs) after irradiation were studied, in which pressure sensitivity of FPI was stable while temperature sensitivity curves of the irradiated FBG did not coincide.

Lactulose and epilactose are nondigestible disaccharides, which can be interconverted from lactose directly by using cellobiose 2-epimerase as catalyst. The characteristics of cellobiose 2-epimerase and its application in enzymatic production of lactulose and epilactose are discussed in this chapter.

A novel three-dimensional (3D) force sensor based on an ultrasensitive all-fiber extrinsic Fabry–Perot (FP) strain sensor and a paperclip-shaped elastomer is proposed and demonstrated. Three FP strain sensors, fabricated by a 157 nm laser micromachining system, are respectively bonded on the three induction beams of the elastomer for sensing their strain variations induced by different direction forces ( F x , F y , F z ). The measured forces are calculated by the combination of a 3 × 3 calibration matrix and the least squares iterative method. Finite element simulation analysis and experimental results both show the 3D force sensor has perfect linearity with better than 0.999 and low crosstalk. Moreover, the experimental results indicate it exhibits a high-repeatability precision of 3D force measurement with less than 0.8%. The 3D force sensor based on the FP strain sensors is reported for the first time, and it offers an extreme potential suitable for 3D force measurements in the field of structural health monitoring and robotic.

Computational tools for enzyme engineering can readily be used in a broad range of food industrial applications. However, there are too many choices when the enzymologists try to solve their own problems computationally, especially when their studies need to be carried out with a combination of tools. The correct choice of methods requires a broad understanding of the knowledge framework. Therefore, we present a comprehensive overview of the current computational tools and basic principles for enzyme design. The tools can be classified into several groups, including bioinformatics approaches and the calculation methods based on static systems and dynamics systems. In addition, we also provide some successful examples in the food industrial applications to show that the modern tools can dramatically reduce the experimental effort and can help us better understand the catalytic mechanism of food enzymes.

Directed evolution using random mutation in vast sequence space leads to the low probability of obtaining target proteins. Emerging engineering strategies with computational tools are developed for more trustable outcomes. We used some semi-rational design methods to modify an industrial enzyme, namely cellobiose 2-epimerase (CE). A mutant was selected for its better thermostability and isomerization activity. The tradeoffs between thermostability, epimerization activity and isomerization activity of the CE mutants were different. To investigate the computational prediction performance of protein stability upon point mutations, molecular dynamics (MD) simulation analyses were conducted. The root mean square deviation (RMSD) and hydrogen bond analyses reproduced the correct trends in stability changes of the wild-type and mutated CEs with relatively high accuracy (correlation coefficients r ~ 0.5–0.8). The simulation temperature and time are important factors that influence the prediction performance. Our result shows that thermostability predictors calculated from MD simulation do better in predicting the thermostability changes of the mutated enzymes than the predictors using static-state information of the enzymes.

Cellobiose 2-epimerase (CE) is a promising industrial enzyme that can be utilized in the dairy industry. More thermostable CEs from different microorganisms are still needed for a higher lactulose productivity. This study demonstrated the feasibility to use molecular dynamics (MD) simulation as the preliminary computational filter for thermostable enzymes screening. Sequence information of eleven uncharacterized CEs were chosen to be analyzed by MD simulations. The CE from Dictyoglomus thermophilum (Dith-CE) was determined experimentally to be one of the most thermostable CEs with the highest epimerization (160 ± 6.5 U mg−1) and isomerization activities (3.52 ± 0.23 U mg−1) among all the reported CEs. This enzyme shows the highest isomerization activity at 85 °C and pH 7.0. The kinetic parameters (kcat and Km) of isomerization activity of this CE are 3.98 ± 0.3 s−1 and 235.2 ± 11.2 mM, respectively. These results suggest that the CE from Dith-CE is a promising lactulose-producing enzyme.

A temperature-insensitive fiber-optic tip sensors array is proposed for multipoint refractive index measurement using optical carrier based on microwave reflection (OCMR). The tip sensors array is made of a series of cleaved fiber end-faces and is spatially multiplexed by physically connecting with a fiber-optic splitter with different lengths of short delay fiber. A sensors array with eight sensing tips is demonstrated for multipoint refractive index measurement. Experimental results show that it can offer a high refractive-index resolution of 3.60 × 10−6 RIU and a low temperature-refractive index cross sensitivity of 3.74 × 10−7 RIU/°C. Such a sensors array not only possesses excellent sensing performances, but also can be integrated into a chip for biochemical sensing applications.

This work proposes an ultrasensitive, temperature-insensitive, all-fiber inline Fabry–Perot (FP) strain sensor for aerodynamic coefficients measurements of a hypervelocity ballistic correlation model 2 in a Φ 1 hypersonic wind tunnel. The FP sensors fabricated using 157 nm laser micromachining system are structurally simple, small-sized, and high-temperature resistance. 16 FP sensors are installed on a six-force balance, which is mounted inside the model, to sense the aerodynamic forces and moments of the model, and then the model’s aerodynamic coefficients are calculated based on aerodynamic theory according to the test data. A new temperature-compensated method is proposed to improve measurement accuracy of aerodynamic coefficients via eliminating temperature-induced measurement errors. Experimental results show, at high temperatures, the FP sensors based on the balance (FP balance) exhibits a high-repeatability precision of the aerodynamic coefficients measurement of less than 1%, and match well with the results of the traditional method using foil-resistive strain sensors. This enhanced-sensitivity FP sensor is currently the most promising alternative to foil-resistive strain sensors for aerodynamic tests among kinds of fiber-optic strain sensors to the best of our knowledge. The FP balance satisfies the requirements of practical application of aerodynamic characteristic tests, and opens up another test system of the field.

Background/Aims: MicroRNA-142-3p (miR-142-3p) is dysregulated in many malignancies and may function as a tumor suppressor or oncogene in tumorigenesis and tumor development. However, few studies have investigated the clinical significance and biological function of miR-142-3p in hepatocellular carcinoma (HCC). Methods: The expression levels of taurine upregulated gene 1 (TUG1), miR-142-3p, and zinc finger E-box-binding homeobox 1 (ZEB1) were evaluated in HCC tissues and cell lines by quantitative real-time PCR. MTT and colony formation assays were used to detect cell proliferation ability, transwell assays were used to assess cell migration and invasion, and luciferase reporter assays were used to examine the interaction between the long noncoding RNA TUG1 and miR-142-3p. Tumor formation was evaluated through in vivo experiments. Results: miR-142-3p was significantly downregulated in HCC tissues, but TUG1 was upregulated in HCC tissues. Knockdown of TUG1 and upregulation of miR-142-3p inhibited cell proliferation, cell migration, cell invasion, and the epithelial-mesenchymal transition (EMT). miR-142-3p was found to be a prognostic factor of HCC, and the mechanism by which TUG1 upregulated ZEB1 was via direct binding to miR-142-3p. In vivo assays showed that TUG1 knockdown suppressed cell proliferation and the EMT in nude mice. Conclusion: The results of this study suggest that the TUG1/miR-142-3p/ ZEB1 axis contributes to the formation of malignant behaviors in HCC.

3-Hydroxypropionaldehyde (3-HPA) is a potential valuable chemical and new broad-spectrum antimicrobial substance. In order to improve the conversion of 3-HPA/glycerol, our work studied the two-step process from glycerol to 3-HPA, and investigated the influence of cell harvest time, glycerol concentration, biomass concentration, pH and temperature on the production of 3-HPA by Lactobacillus reuteri CG001, respectively. The results showed that molar conversion yield of 3-HPA/glycerol reached 97.9% under the condition that 200 mmol·L −1 glycerol was converted by 25.3 g·L −1 resting cell for 1 h at 30°C. The cells could not be reused directly because the L. reuteri almost lost its bioconversion activity completely, but the ability of glycerol conversion could gradually recover if the fresh medium was added to the deactivated cell for 4 h.