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Learning-enabled spectroscopic analysis, promising for automated real-time analysis of chemicals, is facing several challenges. Firstly, a typical machine learning model requires a large number of training samples that physical systems can not provide. Secondly, it requires the testing samples to be in range with the training samples, which often is not the case in the real world. Further, a spectroscopy device is limited by its memory size, computing power, and battery capacity. That requires highly efficient learning models for on-site analysis. In this paper, by analyzing multi-gas mixtures and multi-molecule suspensions, we first show that orders of magnitude reduction of data dimension can be achieved as the number of principal components that need to be retained is the same as the independent constituents in the mixture. From this principle, we designed highly compact models in which the essential principal components can be directly extracted from the interrelations between the individual chemical properties and principal components; and only a few training samples are required. Our model can predict the constituent concentrations that have not been seen in the training dataset and provide estimations of measurement noises. This approach can be extended as an effectively standardized method for principle component extraction.

Shellfish poisonings have posed severe risks to human health globally. The Canadian Shellfish Sanitation Program was established in 1948 to monitor the toxin levels at shellfish harvesting sites along the coast of six provinces in Canada. Domoic acid has been a causal toxin for amnesic shellfish poisoning, and a macro-scale analysis of the temporal and spatial variation of domoic acid along Canada's coast was conducted in this study. We aggregated the toxin levels by week in blue mussel (Mytilus edulis) and soft-shell clam (Mya arenaria) samples, respectively, over a one-year scale. The subsequent application of Functional Principal Component Analysis unveiled that magnitudes of seasonal variation and peaked DA levels around early summer, spring, or mid-fall formed the largest variation in the toxin levels in blue mussels along the coastlines of British Columbia and Prince Edward Island and in soft-shell calms along those of New Brunswick and Nova Scotia. In Quebec, the DA levels were low and varied mostly in terms of the overall magnitude from spring to fall. Downstream correlation analyses in British Columbia further discovered that, at most sites, the strongest correlations were negative between precipitation as well as inorganic nutrients (including nitrate, nitrite, phosphate, and silicate) on one side and DA a few weeks afterward on the other. These findings indicated associations between amnesic shellfish poisoning and environmental stresses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024. Published by Elsevier B.V. All rights reserved.)

Paralytic shellfish toxins (PST) in shellfish products have led to severe risks to human health. To monitor the risk, the Canadian Shellfish Sanitation Program has been collecting longitudinal PST measurements in blue mussel (Mytilus edulis) and soft-shell clam (Mya arenaria) samples in six coastal provinces of Canada. The spatial distributions of major temporal variation patterns were studied via Functional Principal Component Analysis. Seasonal increases in PST contamination were found to vary the most in terms of magnitude along the coastlines, which provides support for location-specific management of the time-sensitive PST contamination. In British Columbia, the first functional principal component (FPC1) indicated the variance among the magnitudes, while FPC2 indicated the seasonality of the PST levels. The temporal variations tended to be positively correlated with the abundance of dianoflagellates Alexandrium spp., and negatively with precipitation and inorganic nutrients. These findings indicate the underlying mechanism of PST variation in various geographical settings. In New Brunswick, Prince Edward, and Nova Scotia, the top FPCs indicated that the PST contamination differed mostly in the seasonal increase of the PST level during summer., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2024. Published by Elsevier Inc. All rights reserved.)

Mechanical failure and chemical degradation of device heterointerfaces can strongly influence the long-term stability of perovskite solar cells (PSCs) under thermal cycling and damp heat conditions. We report chirality-mediated interfaces based on R -/ S -methylbenzyl-ammonium between the perovskite absorber and electron-transport layer to create an elastic yet strong heterointerface with increased mechanical reliability. This interface harnesses enantiomer-controlled entropy to enhance tolerance to thermal cycling-induced fatigue and material degradation, and a heterochiral arrangement of organic cations leads to closer packing of benzene rings, which enhances chemical stability and charge transfer. The encapsulated PSCs showed retentions of 92% of power-conversion efficiency under a thermal cycling test (-40°C to 85°C; 200 cycles over 1200 hours) and 92% under a damp heat test (85% relative humidity; 85°C; 600 hours).

The segmentation of abnormal regions is vital in smart manufacturing. The blurring sauce-packet leakage segmentation task (BSLST) is designed to distinguish the sauce packet and the leakage's foreground and background at the pixel level. However, the existing segmentation system for detecting sauce-packet leakage on intelligent sensors encounters an issue of imaging blurring caused by uneven illumination. This issue adversely affects segmentation performance, thereby hindering the measurements of leakage area and impeding the automated sauce-packet production. To alleviate this issue, we propose the two-stage illumination-aware sauce-packet leakage segmentation (ISLS) method for intelligent sensors. The ISLS comprises two main stages: illumination-aware region enhancement and leakage region segmentation. In the first stage, YOLO-Fastestv2 is employed to capture the Region of Interest (ROI), which reduces redundancy computations. Additionally, we propose image enhancement to relieve the impact of uneven illumination, enhancing the texture details of the ROI. In the second stage, we propose a novel feature extraction network. Specifically, we propose the multi-scale feature fusion module (MFFM) and the Sequential Self-Attention Mechanism (SSAM) to capture discriminative representations of leakage. The multi-level features are fused by the MFFM with a small number of parameters, which capture leakage semantics at different scales. The SSAM realizes the enhancement of valid features and the suppression of invalid features by the adaptive weighting of spatial and channel dimensions. Furthermore, we generate a self-built dataset of sauce packets, including 606 images with various leakage areas. Comprehensive experiments demonstrate that our ISLS method shows better results than several state-of-the-art methods, with additional performance analyses deployed on intelligent sensors to affirm the effectiveness of our proposed method.

Silkworm pupae, by-product of sericulture industry, is massively discarded. The degradation rate of silkworm pupae protein is critical to further employment, which reduces the impact of waste on the environment. Herein, magnetic Janus mesoporous silica nanoparticles immobilized proteinase K mutant T206M and Mucor circinelloides aspartic protease were employed in the co-degradation. The thermostability of T206M improved by enhancing structural rigidity (t 1/2 by 30 min and T 50 by 5 °C), prompting the degradation efficiency. At 65 °C and pH 7, degradation rate reached the highest of 61.7%, which improved by 26% compared with single free protease degradation. Besides, the immobilized protease is easy to separate and reuse, which maintains 50% activity after 10 recycles. Therefore, immobilized protease co-degradation was first applied to the development and utilization of silkworm pupae resulting in the release of promising antioxidant properties and reduces the environmental impact by utilizing a natural and renewable resource., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

FAPbI 3 stands out as an ideal candidate for the photoabsorbing layer of perovskite solar cells (PSCs), showcasing outstanding photovoltaic properties. Nonetheless, stabilizing photoactive α-FAPbI 3 remains a challenge due to the lower formation energy of the competitive photoinactive δ-phase. In this study, we employ tetraethylphosphonium lead tribromide (TEPPbBr 3 ) single crystals as templates for the epitaxial growth of PbI 2 . The strategic use of TEPPbBr 3 optimizes the evolution of intermediates and the crystallization kinetics of perovskites, leading to high-quality and phase-stable α-FAPbI 3 films. The TEPPbBr 3 -modified perovskite exhibits optimized carrier dynamics, yielding a champion efficiency of 25.13% with a small voltage loss of 0.34 V. Furthermore, the target device maintains 90% of its initial PCE under maximum power point (MPP) tracking over 1000 h. This work establishes a promising pathway through single crystal seed based epitaxial growth for achieving satisfactory crystallization regulation and phase stabilization of α-FAPbI 3 perovskites toward high-efficiency and stable PSCs.

The biofilm of an engineered strain is limited by slow growth and low yield, resulting in an unsatisfactory ability to resist external stress and promote catalytic efficiency. Here, biofilms used as robust living catalysts were manipulated through dual functionalized gene regulation and carrier modification strategies. The results showed that gene overexpression regulates the autoinducer-2 activity, extracellular polymeric substance content and colony behavior of Escherichia coli, and the biofilm yield of csgD overexpressed strains increased by 79.35 % compared to that of the wild type strains (p < 0.05). In addition, the hydrophilicity of polyurethane fibres modified with potassium dichromate increased significantly, and biofilm adhesion increased by 105.80 %. Finally, the isoquercitrin yield in the catalytic reaction of the biofilm reinforced by the csgD overexpression strain and the modified carrier was 247.85 % higher than that of the untreated group. Overall, this study has developed engineered strains biofilm with special functions, providing possibilities for catalytic applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The growing preference for incorporating microbial aspartic proteases in industries is due to their high catalytic function and high degree of substrate selectivity. These properties, however, are attributable to molecular alterations in their structure and a variety of other characteristics. Molecular tools, functional genomics, and genome editing technologies coupled with other biotechnological approaches have aided in improving the potential of industrially important microbial proteases by addressing some of their major limitations, such as: low catalytic efficiency, low conversion rates, low thermostability, and less enzyme yield. However, the native folding within their full domain is dependent on a surrounding structure which challenges their functionality in substrate conversion, mainly due to their mutual interactions in the context of complex systems. Hence, manipulating their structure and controlling their expression systems could potentially produce enzymes with high selectivity and catalytic functions. The proteins produced by microbial aspartic proteases are industrially capable and far-reaching in regulating certain harmful distinctive industrial processes and the benefits of being eco-friendly. This review provides: an update on current trends and gaps in microbial protease biotechnology, exploring the relevant recombinant strategies and molecular technologies widely used in expression platforms for engineering microbial aspartic proteases, as well as their potential industrial and biotechnological applications.

Background: With the requirements of environmental, cost and economic sustainability, new sources of alternative proteins in the livestock industry are receiving increasing attention. Mulberry (Morus alba L.) leaves are a unique feed resource because of their high protein content and large availability. Therefore, mining sustainable protein suitable for the animal husbandry industry in sericulture resources could achieve a win-win situation., Results: The protein content in mulberry leaves is 232.10-386.16 g kg -1 , and the mean value of crude fat content is 43.76 ± 8.48 g kg -1 , which has the advantages of protein content and energy. In addition, the average content of phytic acid in mulberry leaves is only 1.88 ± 0.56 g kg -1 , which means that it is not inhibited in terms of nutrient absorption. Meanwhile, the digestibility of protein was Bean pulp > Sample 8 ≈ Alfalfa ≈ Sample 13 ≈ Cottonseed meal > Fish meal, and the β-turn and particle size of mulberry leaf protein are more conducive to digestion in vitro. Furthermore, the protein of Sample 13 had the richest essential amino acids (252.00 g kg -1 ) and the highest essential amino acid index (EAAI), which was superior to conventional feed protein. In addition, the partial substitution of mulberry leaf protein (15%) significantly increased the EAAI value of conventional feed protein. However, to balance nutrition, it is necessary to combine mulberry leaf protein with other proteins to further broaden its application field., Conclusion: Mulberry leaves are a new source of feed protein, which helps to alleviate the two major problems of mulberry resource surplus and feed protein resource shortage. © 2023 Society of Chemical Industry., (© 2023 Society of Chemical Industry.)

Study Objective: Most laparoscopic surgeries under general anesthesia are performed in noisy environments, although the effect of intraoperative noise reduction on postoperative pain remains uncertain. This study aimed to explore whether postoperative pain could be reduced through the intraoperative use of noise-cancelling headphones., Design: This study was conducted as a prospective parallel-group randomized clinical trial., Setting: Operating room and surgery room., Patients: Ninety patients who underwent laparoscopic surgery under general anesthesia., Interventions: In the intervention group, noise-cancelling headphones were used to reduce noise intensity during laparoscopic surgery under general anesthesia., Measurements: The primary outcome was the maximum movement-evoked pain intensity within 24 h post-surgery, measured using a 10-point numeric rating scale. Secondary outcomes included the maximum resting pain score and total opioid consumption during the 24-h period post-surgery. Mean intraoperative noise and the proportion of intraoperative time with noise intensity ≥70 dB were recorded., Main Results: The maximum movement-evoked pain score was significantly lower in the intervention group than in the control group (mean score [SD], 2.7 [1.0] and 4.0[1.0], respectively; P < 0.001). The intervention group required significantly fewer opioids than the control group (mean [SD], 44.2 [12.8] and 51.3[17.5] mg, respectively; P = 0.032). In the control group, but not the intervention group, all postoperative pain scores were significantly associated with the proportion of intraoperative time with noise intensity ≥70 dB, which was an independent risk factor for postoperative pain., Conclusion: During laparoscopic surgery under general anesthesia, intraoperative noise isolation using noise-cancelling headphones is a safe and effective strategy for relieving postoperative pain and decreasing total opioid analgesic consumption., Competing Interests: Declaration of Competing Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as potential conflicts of interest., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Most patients are in a noisy environment during abdominal surgery under general anesthesia. This study included patients who underwent abdominal surgery under general anesthesia and established an animal model to determine whether intraoperative noise affects postoperative pain., Materials and Methods: This prospective study included 200 patients who underwent abdominal surgery under general anesthesia. Intraoperative noise and electroencephalograms were continuously recorded, and the mean level and time proportion of noise intensity of greater than 70 dB were calculated. Maximum postoperative pain was assessed using a numerical rating scale at 0-12 h and 12-24 h after surgery, and postoperative analgesia consumption in patients receiving patient-controlled intravenous analgesia was recorded. Postoperative pain intensity and electroencephalogram amplitude were compared between patients with high-noise exposure (time proportion of noise intensity greater than 70 dB ≥40%) and low-noise exposure (<40%). Mechanical pain sensitivity was tested in two groups of mice with plantar incisions exposed to 40 dB or 70-100 dB., Results: The time proportion of noise intensity greater than 70 dB was identified as an independent risk factor for postoperative pain intensity ( P <0.001). P ain numerical rating scale 0-12 h (4.5±1.5 vs. 3.7±1.3, P =0.001) and 12-24 h (3.9±1.5 vs. 3.2±1.1, P =0.004) after surgery in patients with high-noise exposure was significantly higher than in patients with low-noise exposure. The electroencephalogram amplitude of patients with high-noise exposure was significantly lower than that of patients with low-noise exposure ( P <0.05). In the mouse model, mechanical hyperalgesia in the 70-100 dB group was significantly greater than that in the 40 dB group ( P <0.001)., Conclusion: High-level intraoperative noise exposure aggravates the degree of postoperative pain and analgesic needs of patients undergoing abdominal surgery, which may be related to the impact of noise on the neurophysiological activity of the brain and postoperative hyperalgesia., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)

The vast coastline provides Canada with a flourishing seafood industry including bivalve shellfish production. To sustain a healthy bivalve molluscan shellfish production, the Canadian Shellfish Sanitation Program was established to monitor the health of shellfish harvesting habitats, and fecal coliform bacteria data have been collected at nearly 15,000 marine sample sites across six coastal provinces in Canada since 1979. We applied Functional Principal Component Analysis and subsequent correlation analyses to find annual variation patterns of bacteria levels at sites in each province. The overall magnitude and the seasonality of fecal contamination were modelled by functional principal component one and two, respectively. The amplitude was related to human and warm-blooded animal activities; the seasonality was strongly correlated with river discharge driven by precipitation and snow melt in British Columbia, but such correlation in provinces along the Atlantic coast could not be properly evaluated due to lack of data during winter., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Crown Copyright © 2023. Published by Elsevier Ltd. All rights reserved.)

Meteorus pulchricornis is a preponderant parasitic wasp of various lepidopteran pests. The extensive application of broad-spectrum insecticides usually causes serious threats to the olfactory recognition of nontarget insects such as parasitoid wasps. However, the binding mechanism of odorant-binding proteins (OBPs) to insecticides in parasitoid wasps remains unknown. Herein, we find that the MpulOBP6 protein had a strong binding affinity to three insecticides (phoxim, chlorpyrifos, and chlorfenapyr). Results of computational simulations revealed that the hydrophobic interaction contributed by a mass of nonpolar amino acid residues was the primary driving force in the formation and stabilization of MpulOBP6-insecticide complexes. Among them, four residues (Met75, Val84, Phe121, and Pro122) and two residues (Val84 and Phe111) play an essential role in the binding of MpulOBP6 to phoxim and chlorfenapyr, respectively. Our findings could be instrumental to elucidate the effects of insecticide application toward the olfactory recognition of nontarget insects in the processes of agricultural production.

The formulation in which biochemical enzymes are administered in polymer science plays a key role in retaining their catalytic activity. The one-step synthesis of polymers with highly sequence-controlled enzymes is a strategy employed to provide enzymes with higher catalytic activity and thermostability in material sustainability. Enzyme-catalyzed chain growth polymerization reactions using activated monomers, protein-polymer complexation techniques, covalent and non-covalent interaction, and electrostatic interactions can provide means to develop formulations that maintain the stability of the enzyme during complex material processes. Multifarious applications of catalytic enzymes are usually attributed to their efficiency, pH, and temperature, thus, progressing with a critical structure-controlled synthesis of polymer materials. Due to the obvious economics of manufacturing and environmental sustainability, the green synthesis of enzyme-catalyzed materials has attracted significant interest. Several enzymes from microorganisms and plants via enzyme-mediated material synthesis have provided a viable alternative for the appropriate synthesis of polymers, effectively utilizing the one-step approach. This review analyzes more and deeper strategies and material technologies widely used in multi-enzyme cascade platforms for engineering polymer materials, as well as their potential industrial applications, to provide an update on current trends and gaps in the one-step synthesis of materials using catalytic enzymes.

High-quality perovskite light harvesters and robust organic hole extraction layers are essential for achieving high-performing perovskite solar cells (PSCs). We introduce a phosphonic acid-functionalized fullerene derivative in mixed-cation perovskites as a grain boundary modulator to consolidate the crystal structure, which enhances the tolerance of the film against illumination, heat, and moisture. We also developed a redox-active radical polymer, poly(oxoammonium salt), that can effectively p-dope the hole-transporting material by hole injection and that also mitigates lithium ion diffusion. Power conversion efficiencies of 23.5% for 1-square-centimeter mixed-cation-anion PSCs and 21.4% for 17.1-square-centimeter minimodules were achieved. The PSCs retained 95.5% of their initial efficiencies after 3265 hours at maximum power point tracking under continuous 1-sun illumination at 70° ± 5°C.

β-1,3-1,4-Glucanase is an indispensable biocatalyst in barley brewing industry for its crucial effect in reducing the viscosity of mash. However, the unsatisfactory thermostability greatly limited its application performance. In this study, structure-based surface charge engineering was conducted aiming at thermostability improvement of BisGlu16B, a highly active β-1,3-1,4-glucanase from Bispora sp. MEY-1. By applying the enzyme thermal stability system (ETSS), residues D47, D213, and D253 were inferred to be critical sites for thermal properties. Single (D47A, D213A, and D253A) and combination (D47A/D213A/D253A) mutants were generated and compared with BisGlu16B. Among all improved mutants, D47A/D213A/D253A outstanded in thermostability. In comparison with BisGlu16B, its T 50 and T m were respectively increased by 7.0 °C and 4.3 °C, while the t 1/2 at 70 °C was 8.1 times that of the wild type. Furthermore, the catalytic activity of D47A/D213A/D253A also increased by 42.5%, compared with BisGlu16B (42,900 ± 300 U/mg vs. 30,100 ± 800 U/mg). Comparing with BisGlu16B and commercial enzyme treatment groups, under simulated malting conditions, efficiency improvement was observed in decreasement of viscosity (35.5% and 90.7%) and filtration time (30.9% and 34.6%) for D47A/D213A/D253A treatment group. Molecular dynamics simulation showed that mutation sites A47, A213, and A253 increased the protein rigidity by lowering the overall root mean square deviation (RMSD). This study may bring optimization of technology and improvement of producing efficiency to the present brewing industry., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

N-glycosylation alters the properties of different enzymes in different ways. Rhizopus homothallicus was first described as an environmental isolate from desert soil in Guatemala. A new gene encoding glucanase RhGlu16B was identified in R. homothallicus. It had high specific activity (9673 U/mg) when barley glucan was used as a substrate, and β-glucan is hemicellulose that is abundant in nature. RhGlu16B has only one N-glycosylation site in its Ala55-Gly64 loop. It was found that N-glycosylation increased its T m value and catalytic efficiency by 5.1 °C and 59%, respectively. Adding N-glycosylation to the same region of GH16 family glucanases TlGlu16A (from Talaromyces leycettanus) increased its thermostability and catalytic efficiency by 6.4 °C and 38%, respectively. In a verification experiment using GH16 family glucanases BisGlu16B (from Bisporus) in which N-glycosylation was removed, N-glycosylation also appeared to promote thermostability and catalytic efficiency. N-glycosylation reduced the overall root mean square deviation of the enzyme structure, creating rigidity and increasing overall thermostability. This study provided a reference for the molecular modification of GH16 family glucanases and guided the utilization of β-glucan in hemicellulose., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The thermal imaging pedestrian-detection system has excellent performance in different lighting scenarios, but there are problems regarding weak texture, object occlusion, and small objects. Meanwhile, large high-performance models have higher latency on edge devices with limited computing power. To solve the above problems, in this paper, we propose a real-time thermal imaging pedestrian-detection method for edge computing devices. Firstly, we utilize multi-scale mosaic data augmentation to enhance the diversity and texture of objects, which alleviates the impact of complex environments. Then, the parameter-free attention mechanism is introduced into the network to enhance features, which barely increases the computing cost of the network. Finally, we accelerate multi-channel video detection through quantization and multi-threading techniques on edge computing devices. Additionally, we create a high-quality thermal infrared dataset to facilitate the research. The comparative experiments on the self-built dataset, YDTIP, and three public datasets, with other methods show that our method also has certain advantages.

To increase the reuse of food residues, multifrequency countercurrent ultrasonic treatment was used to enhance the extraction yield of defatted mulberry seed protein (DMSP), and sweet-flavored peptides from DMSP hydrolysates (DMSPHs) were obtained for the first time. Here, the DMSP yield was increased by 16.2% (p < 0.05) while the power density was halved compared with single-frequency ultrasonic treatment. According to Fick's second law, a molecular diffusion dynamics model was developed to be suitable for predicting the pretreatment conditions (R 2  = 0.9785). After that, the sweet-flavored peptides were purified and the main amino acid sequences were identified, i.e., FEGGSIE, KDFPEAHSQAT, and GSQPAEGAK. Moreover, the antioxidant activities of DMSPHs prepared with tri-frequency treatment was higher than 60%. The DMSPHs retarded the growth of HepG2 cells in vitro, increased the necrotic quadrant (Q1-UL), and extended the S phase. Therefore, the sweet-flavored peptides prepared from DMSPHs using the multifrequency-ultrasonic treatment have significant biological activities., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Biorefinery of Ramulus mori with lower energy consumption through improved enzyme and pretreatment strategies was reported. Directed evolution and saturation mutagenesis were used for the modification of xylanase, the yield of fermentable sugars and the degree of synergy (DS) were determined for different pretreatment (seawater/non-seawater) and enzyme treatment groups (xylanase/cellulase/co-treatment). The dominant mutant I133A/Q143Y of Bispora sp. xylanase XYL10C&#95;ΔN was obtained with improved specific activity (1860 U/mg), catalytic efficiency (1150 mL/s∙mg) at 40 °C, and thermostability (T 50 increased by 7 °C). With the pretreatment of seawater immersion, the highest yield of fermentable sugars for Ramulus mori at 40 °C reached 199 μmol/g when hydrolyzed with cellulase and I133A/Q143Y, with the highest DS of 2.6; this was 4.5-fold that of the group hydrolyzed by cellulase alone with non-seawater pretreatment. Thus, bioconversion of reducing sugar from Ramulus mori was improved significantly at lower temperatures, which provides an efficient and energy-saving wayfor biofuel production., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Lignocellulosic biorefining for producing biofuels poses technical challenges. It is usually conducted over a long time using heat, making it energy intensive. In this study, we lowered the energy consumption of this process through an optimized enzyme and pretreatment strategy. First, the dominant mutant M137E/N269G of Bispora sp. MEY-1XYL10C&#95;ΔN was obtained by directed evolution with highcatalytic efficiency (970 mL/s∙mg)and specific activity (2090 U/mg)at 37 °C, and thermostability was improved (T 50 increased by5 °C). After pretreatment with seawater immersionfollowing steam explosion,bagasse was co-treated with cellulase and M137E/N269G under mild conditions (37 °C), the resulting highest yield of fermentable sugars reached 219 µmol/g of bagasse,46% higher than that of the non-seawater treatment group, with the highest degree of synergy of 2.0. Pretreatment with seawater following steam explosion and synergistic hydrolysis through high activity xylanase and cellulase helped to achieve low energy degradation of lignocellulosic biomass., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background: Xylanase, an important accessory enzyme that acts in synergy with cellulase, is widely used to degrade lignocellulosic biomass. Thermostable enzymes with good catalytic activity at lower temperatures have great potential for future applications in the feed and fuel industries, which have distinct demands; however, the potential of the enzymes is yet to be researched., Results: In this study, a structure-based semi-rational design strategy was applied to enhance the low-temperature catalytic performance of Bispora sp. MEY-1 XYL10C&#95;∆N wild-type (WT). Screening and comparisons were performed for the WT and mutant strains. Compared to the WT, the mutant M53S/F54L/N207G exhibited higher specific activity (2.9-fold; 2090 vs. 710 U/mg) and catalytic efficiency (2.8-fold; 1530 vs. 550 mL/s mg) at 40 °C, and also showed higher thermostability (the melting temperature and temperature of 50% activity loss after 30 min treatment increased by 7.7 °C and 3.5 °C, respectively). Compared with the cellulase-only treatment, combined treatment with M53S/F54L/N207G and cellulase increased the reducing sugar contents from corn stalk, wheat bran, and corn cob by 1.6-, 1.2-, and 1.4-folds, with 1.9, 1.2, and 1.6 as the highest degrees of synergy, respectively., Conclusions: This study provides useful insights into the underlying mechanism and methods of xylanase modification for industrial utilization. We identified loop2 as a key functional area affecting the low-temperature catalytic efficiency of GH10 xylanase. The thermostable mutant M53S/F54L/N207G was selected for the highest low-temperature catalytic efficiency and reducing sugar yield in synergy with cellulase in the degradation of different types of lignocellulosic biomass., (© 2021. The Author(s).)

To prepare a nutritional supplement using silkworm pupae oil (SPO) as a feedstock, a microfluidic reactor with a smart hydrogel immobilized lipase was first constructed to reduce the relative content of palmitic acid at sn-1,3 and improve the nutritional function. The effects of flow rate, reaction temperature, and substrate molar ratio were investigated. In vitro digestion and pH-stat models were employed to analyze the digestion feature after the modification of SPO, while HPLC-ELSD, zeta potential, DSC, and TGA were used to evaluate the nutritional function. The relative content of "OOO" and "OPO" type triglycerides was increased by 49.48% and 107.67%, and that of palmitic acid at sn-1,3 was decreased by 49.61% in 10 s. After the verification of the in vitro digestion model, the fatty acid release rate of the modified SPO was significantly improved by 22.07%, indicating the nutritional function improvement of SPO. Therefore, the nutritional function of SPO has been improved successfully by the application of a microchannel reactor with photo-immobilized lipase, which could set a reference for the utilization of insect oil resources.

A large number of defective mulberries are discarded each year because mulberries are easy to break. The red pigments from defective mulberries are recognized as the sustainable sources of anthocyanins extracted from nature. Cyanidin-3-O-rutinoside and cyanidin-3-O-glucoside are the main components of mulberry red pigments, accounting for 50% and 40% of the total, respectively. Cyanidin-3-O-glucoside exhibits anticancer, hypoglycemic, and liver and visceral protection properties. Cyanidin-3-O-glucoside can be prepared by enzymatically hydrolyzing the rhamnosidase bond of cyanidin-3-O-rutinoside. To obtain mulberry red pigment with a high purity of cyanidin-3-O-glucoside, immobilized α-L-rhamnosidase was added to the aqueous two-phase system to construct a liquid-liquid-solid three-phase enzyme catalytic system. After optimization, the three-phase system was composed of 27.12% (w/w) ethanol, 18.10% (w/w) ammonium sulfate, 15% (w/w) mulberry juice, 4.24% (w/w) immobilized α-L-rhamnosidase, and 35.54% (w/w) pure water. The three-phase system was employed to enrich and purify cyanidin-3-O-glucoside at pH 5 and 45 °C for 1 h. The purity of cyanidin-3-O-glucoside was increased from 40 to 82.42% with cyanidin-3-O-rutinoside conversion of 60.68%. The immobilized α-L-rhamnosidase could be reused seven times, maintaining a relative activity of over 50%. Overall, the developed system provided an efficient and simple approach for high purity mulberry red pigment production and recycling in the field of sustainable agriculture. Graphical abstract.

α-Linolenic acid (ALA) is recognised to have a regulatory effect on cardiovascular diseases. Due to the low bioavailability of linseed oil (LINO), which is the most common ALA supplement, it is necessary to find a replacement for ALA supplements that is more easily accepted by the human body. The content of ALA in silkworm pupae oil (SPO) is 32.60 ± 0.67%, and SPO can be substituted as a dietary lipid to meet the demand of the human body. In the present study, a pH-stat system was used to investigate the release degree of free fatty acids (FFAs) from SPO and construct a first-order kinetic model. Digestion experiments in vitro with different lipids showed that the maximum release FFA levels were SPO > SO (soybean oil) > LO (lard oil) > MSO (mulberry seed oil) > LINO, and the first-order kinetic apparent rate constants were LINO > SPO > LO > SO > MSO. Triacylglycerol (TAG) and fatty acid composition are the decisive factors in determining the level of lipid digestion. Therefore, the maximum level of FFAs released from SPO (84.34 ± 1.37%) was much higher than that of LINO (49.78 ± 0.52%) when the hydrolysis rates were 0.2114 s -1 and 0.2249 s -1 , respectively. In addition, the smaller emulsion droplet size (609.24 ± 43.46 nm) and weaker surface charge (-17.93 ± 0.42 mV) also resulted in higher levels of SPO under in vitro digestion conditions. Meanwhile, due to low melting and crystallisation temperature, SPO is quickly absorbed by the human body. Overall, SPO can be used as a new alternative for ALA supplements based on its superior digestive properties.

Perovskite solar cells (PSCs) have rapidly developed and achieved power conversion efficiencies of over 20% with diverse technical routes. Particularly, planar-structured PSCs can be fabricated with low-temperature (≤150 °C) solution-based processes, which is energy efficient and compatible with flexible substrates. Here, the efficiency and stability of planar PSCs are enhanced by improving the interface contact between the SnO 2 electron-transport layer (ETL) and the perovskite layer. A biological polymer (heparin potassium, HP) is introduced to regulate the arrangement of SnO 2 nanocrystals, and induce vertically aligned crystal growth of perovskites on top. Correspondingly, SnO 2 -HP-based devices can demonstrate an average efficiency of 23.03% on rigid substrates with enhanced open-circuit voltage (V OC ) of 1.162 V and high reproducibility. Attributed to the strengthened interface binding, the devices obtain high operational stability, retaining 97% of their initial performance (power conversion efficiency, PCE > 22%) after 1000 h operation at their maximum power point under 1 sun illumination. Besides, the HP-modified SnO 2 ETL exhibits promising potential for application in flexible and large-area devices., (© 2020 Wiley-VCH GmbH.)

The long-term stability of perovskite solar cells (PSCs) remains an issue impeding their commercialization. Generally, polycrystalline perovskite thin films have many defects on the grain boundaries, which affect the optoelectronic performance and stability of the devices under moisture, heat, illumination, and the presence of an electric field condition. The O-donor Lewis base is often employed to regulate the performance of PSCs such as carbonyl and carboxyl compounds. Herein, we have developed a concept of radical molecular modulation using the O-donor group for high-performance perovskite photovoltaic devices. The judiciously designed radical modulators 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), which located at the perovskite grain boundary through interaction with the perovskite surface sites, effectively passivated the surface defects while templating the formation of large grain crystal and high-quality perovskite thin films. Accordingly, the optimized TEMPO-modulated PSCs achieved a power conversion efficiency of 20.73% with superior stability. This work makes an important contribution for exploring the effect of radical in perovskites to improve the performance of PSCs and other optoelectronic devices., (Copyright © 2020 Peng, Zheng, Zhang, You, Li, Zhao, Zhang, Luo, Zeng and Li.)

Developing circular economy is the only way to improve the efficiency of resource utilization. Whole-cell catalysis is an effective method to recycle enzymes, improve catalytic efficiency, and reduce production costs. The enzyme, α-L-rhamnosidase has considerable application prospects in the field of biocatalysis as it can hydrolyze a variety of α-L rhamnoses. In the present study, the genes for α-L-rhamnosidase (rhaB1) and enhanced fluorescent protein (EGFP) were co-expressed using a bi-promoter expression vector pRSFDuet1 and their enzymatic properties were evaluated. To our knowledge, this study has established an effective rhamnosidase-fluorescent indicator and whole-cell catalytic system for the first time. Moreover, we analyzed the change in the activity of the crude rhaB1-EGFP as well as its whole-cell during the biocatalysis process using fluorescence intensity. Recombinant rhaB1-EGFP as a product which contains rhaB1 and EGFP showed higher thermal stability, pH stability, and conversion efficiency than rhaB1, and its optimum temperature for rutin catalysis was ideal for industrial applications. Moreover, under the optimal conditions of a rutin concentration of 0.05 g/L, pH of 6.0, temperature of 40 °C, a yield of 92.5% was obtained. Furthermore, we demonstrated the relationship between the fluorescence intensity and enzyme activity. This study established a highly efficient whole-cell catalytic system whose activity can be evaluated by fluorescence intensity, providing a reference for enzyme recycling., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Xylanase is one of the most extensively used biocatalysts for biomass degradation. However, its low catalytic efficiency and poor thermostability limit its applications. Therefore, improving the properties of xylanases to enable synergistic degradation of lignocellulosic biomass with cellulase is of considerable significance in the field of bioenergy., Results: Using fragment replacement, we improved the catalytic performance and thermostability of a GH10 xylanase, XylE. Of the ten hybrid enzymes obtained, seven showed xylanase activity. Substitution of fragments, M3, M6, M9, and their combinations enhanced the catalytic efficiency (by 2.4- to fourfold) as well as the specific activity (by 1.2- to 3.3-fold) of XylE. The hybrids, XylE-M3, XylE-M3/M6, XylE-M3/M9, and XylE-M3/M6/M9, showed enhanced thermostability, as observed by the increase in the T 50 (3-4.7 °C) and T m (1.1-4.7 °C), and extended t 1/2 (by 1.8-2.3 h). In addition, the synergistic effect of the mutant xylanase and cellulase on the degradation of mulberry bark showed that treatment with both XylE-M3/M6 and cellulase exhibited the highest synergistic effect. In this case, the degree of synergy reached 1.3, and the reducing sugar production and dry matter reduction increased by 148% and 185%, respectively, compared to treatment with only cellulase., Conclusions: This study provides a successful strategy to improve the catalytic properties and thermostability of enzymes. We identified several xylanase candidates for applications in bioenergy and biorefinery. Synergistic degradation experiments elucidated a possible mechanism of cellulase inhibition by xylan and xylo-oligomers., Competing Interests: Competing interestsThe authors declare that they have no competing interests., (© The Author(s) 2019.)

Lipids produced from agricultural and industrial residues using oleaginous microorganisms for use as biofuels are attracting the attention of researchers due to their environmental benefits. However, low efficiencies and high costs limit their application to a certain extent. The present study is the first to use inositol as an enhancer to improve the production and accumulation of lipids during fermentation by the microalga Schizochytrium sp. SR21. The study aimed to maximize the production of lipids and docosahexaenoic acid (DHA) by optimizing the conditions of inositol addition into the fermentation medium. The corresponding key enzyme and metabolite profiles of SR21 were evaluated. The results indicated that the addition of 120 mg L -1 of inositol to the medium at 48 h improved lipid and DHA production by 13.90 and 20.82%, resulting in total concentrations of 22.86 and 8.53 g/L, respectively. Moreover, the ratio of unsaturated fatty acids (UFAs) to saturated fatty acids (SFAs) increased by 23.38% and is consistent with the results of the metabolomic analysis. The activity of enzymes (i.e., PC, G6PDH, NADPH-ME, and ACL) related to fatty acid synthesis in strain SR21 also increased significantly (43.38%, 28.68%, 37.47%, and 19.87%, respectively). Metabolomic analysis also showed that inositol promoted lipid synthesis in SR21 and significantly increased the relative proportion of UFAs by affecting the citrate cycle and SFA and UFA metabolic pathways. Thus, inositol is an ideal enhancer of lipid production and accumulation by oleaginous microorganisms. Graphical abstract.

Reaching the full potential of solar cells based on photo-absorbers of organic-inorganic hybrid perovskites requires highly efficient charge extraction at the interface between perovskite and charge transporting layer. This demand is generally challenged by the presence of under-coordinated metal or halogen ions, causing surface charge trapping and resultant recombination losses. These problems can be tackled by introducing a small molecule interfacial anchor layer based on dimethylbiguanide (DMBG). Benefitting from interactions between the nitrogen-containing functional groups in DMBG and unsaturated ions in CH 3 NH 3 PbI 3 perovskites, the electron extraction of TiO 2 is dramatically improved in association with reduced Schottky-Read-Hall recombination, as revealed by photoluminescence spectroscopy. As a consequence, the power conversion efficiency of CH 3 NH 3 PbI 3 solar cells is boosted from 17.14 to 19.1 %, showing appreciably reduced hysteresis. The demonstrated molecular strategy based on DMBG enables one to achieve meliorations on key figures of merit in halide perovskite solar cells with improved stability., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A β-1,3-1,4-glucanase-encoding gene, Bisglu16B, was identified in Bispora sp. MEY-1. The deduced BisGlu16B consists of an N-terminal signal peptide, a catalytic module of glycoside hydrolase family 16 (GH16), and a C-terminal serine/proline-rich module. After expression in Pichia pastoris GS115, the purified recombinant BisGlu16B showed maximal activity at pH 4.0 and 55 °C and had broad substrate specificity (β-1,3-/β-1,4-mixed, β-1,3-, β-1,4-, and β-1,6-linked glucan, and β-1,4-mannan). The enzyme possessed high specific activities toward barley β-glucan (34 700 U·mg -1 ), lichenan (23 900 U·mg -1 ), and laminarin (9 000 U·mg -1 ). After removing the C-terminal module, the truncated mutant, BisGlu16B-ΔC, retained similar enzymatic properties to the wild type but displayed significantly enhanced activities (up to 2.5-fold). Functional and structural analyses indicated that the C-terminal module plays a key role in the substrate binding of BisGlu16B. This study provided an excellent candidate glucanase for industrial purposes and revealed the functions of a C-terminal serine/proline-rich region.

Background: Improving the hydrolytic performance of hemicellulases to degrade lignocellulosic biomass is of considerable importance for second-generation biorefinery. Xylanase, as the crucial hemicellulase, must be thermostable and have high activity for its potential use in the bioethanol industry. To obtain excellent xylanase candidates, it is necessary to understand the structure-function relationships to provide a meaningful reference to improve the enzyme properties. This study aimed to investigate the catalytic mechanism of a highly active hyperthermophilic xylanase variant, XYL10C-ΔN, for hemicellulose degradation., Results: By removing the N-terminal 66 amino acids, the variant XYL10C-ΔN showed a 1.8-fold improvement in catalytic efficiency and could hydrolyze corn stover more efficiently in hydrolysis of corn stover; however, it retained similar thermostability to the wild-type XYL10C. Based on the crystal structures of XYL10C-ΔN and its complex with xylobiose, Glu175 located on loop 3 was found to be specific to GH10 xylanases and probably accounts for the excellent enzyme properties by interacting with Lys135 and Met137 on loop 2. Site-saturation mutagenesis confirmed that XYL10C-ΔN with glutamate acid at position 175 had the highest catalytic efficiency, specific activity, and the broadest pH-activity profile. The functional roles of Glu175 were also verified in the mutants of another two GH10 xylanases, XylE and XynE2, which showed increased catalytic efficiencies and wider pH-activity profiles., Conclusions: XYL10C-ΔN, with excellent thermostability, high catalytic efficiency, and great lignocellulose-degrading capability, is a valuable candidate xylanase for the biofuel industry. The mechanism underlying improved activity of XYN10C-ΔN was thus investigated through structural analysis and functional verification, and Glu175 was identified to play the key role in the improved catalytic efficiency. This study revealed the importance of a key residue (Glu175) in XYN10C-ΔN and provides a reference to modify GH10 xylanases for improved catalytic performance.

Traps in the photoactive layer or interface can critically influence photovoltaic device characteristics and stabilities. Here, traps passivation and retardation on device degradation for methylammonium lead trihalide (MAPbI 3 ) perovskite solar cells enabled by a biopolymer heparin sodium (HS) interfacial layer is investigated. The incorporated HS boosts the power conversion efficiency from 17.2 to 20.1% with suppressed hysteresis and Shockley-Read-Hall recombination, which originates primarily from the passivation of traps near the interface between the perovskites and the TiO 2 cathode. The incorporation of an HS interfacial layer also leads to a considerable retardation of device degradation, by which 85% of the initial performance is maintained after 70 d storage in ambient environment. Aided by density functional theory calculations, it is found that the passivation of MAPbI 3 and TiO 2 surfaces by HS occurs through the interactions of the functional groups (COO - , SO 3 - , or Na + ) in HS with undersaturated Pb and I ions in MAPbI 3 and Ti 4+ in TiO 2 . This work demonstrates a highly viable and facile interface strategy using biomaterials to afford high-performance and stable perovskite solar cells., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

To reduce intrinsic defect density in perovskite films, various additives are often added into the precursor solution. In this paper, a novel solution, in which isopropanol (IPA) was added into the precursor solution, was developed for the preparation of normal planar perovskite solar cells (PSCs). A champion power conversion efficiency (PCE) of 19.70 % was achieved with this approach. By adding IPA into the precursor solution, CH 3 NH 3 PbI 3 perovskite showed better crystallization and stability, indicating improved film quality. Because of the improved morphology of perovskite crystal, the PCE of PSCs increased. In addition, the unencapsulated PSCs retained high output for up to 40 days in air at room temperature, indicating the stability of PSCs. These results may provide a new avenue for manufacturing high efficiency and high stability PSCs., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Extremophilic xylanases have attracted great scientific and industrial interest. In this study, a GH10 xylanase-encoding gene, Xyl10E, was cloned from Bispora sp. MEY-1 and expressed in Pichia pastoris GS115. Deduced Xyl10E shares the highest identities of 62% and 57% with characterized family GH10 xylanases from Talaromyces leycettanus and Penicillium canescens (structure 4F8X), respectively. Xyl10E was most active at 93 to 95°C and pH 4.0, retained more than 75% or 48% of the initial activity when heated at 80°C or 90°C for 30 min, respectively, and hardly lost activity at pH 1.0 to 7.0, but was completely inhibited by SDS. Two residues, A160 and A161, located on loop 4, were identified to play roles in catalysis. Mutants A160D/E demonstrated higher affinity to substrate with lower Km values, while mutants A161D/E mainly displayed elevated Vmax values. All of these mutants had significantly improved catalytic efficiency. According to the molecular dynamics simulation, the mutation of A160E was able to affect the important substrate binding site Y204 and then improve the substrate affinity, and the mutation of A161D was capable of forming a hydrogen bond with the substrate to promote the substrate binding or accelerate the product release. This study introduces a highly thermophilic fungal xylanase and reveals the importance of loop 4 for catalytic efficiency.

Efficient hydrolysis of pectic materials to sugars requires the synergistic action of endo- and exo-polygalacturonases. Two novel polygalacturonases (exo-TePG28a and endo-TePG28b) were identified in Talaromyces leycettanus JCM12802, overexpressed in Pichia pastoris, and characterized in this report. The specific activities of TePG28a and TePG28b towards polygalacturonic acid were 280±9 and 25,900±502U/mg, respectively. Both enzymes exhibited optimal activities at pH 3.5 and retained highly stable over a broad pH range of 2.0-7.0. Distinct from most fungal polygalacturonases that have low temperature optima, TePG28a and TePG28b were optimally active at 70°C. When treated the grape juice with the enzyme combination (the unit ratio of TePG28a:TePG28b was 1:4), higher pectin-degrading efficiency (up to 140%) was achieved, and light transmittance was improved from 14% to 82%. These favorable enzymatic properties make TePG28a and TePG28b attractive for the applications in the juice industry., (Copyright © 2017. Published by Elsevier Ltd.)

Thermophilic xylanases with high catalytic efficiency are of great interest in the biofuel, food and feed industries. This study identified a GH11 xylanase gene, Tlxyn11B, in Talaromyces leycettanus JCM12802. Recombinant TlXyn11B produced in Pichia pastoris is distinguished by high specific activity (8259 ± 32 U/mg with beechwood xylan as substrate) and excellent pH stability (from 1.0 to 10.5). The beechwood xylan hydrolysates consisted mainly of xylobiose, xylotriose and xylotetraose, thus TlXyn11B could be used for the production of prebiotic xylooligosaccharide. By using the structure-based rational approach, the N-terminal sequence of TlXyn11B was modified for thermostability improvement. Mutants S3F and S3F/D35V/I/Q/M had elevated T m values of 60.01 to 67.84 °C, with S3F/D35I the greatest. Homology modeling and molecular dynamics (MD) simulation analysis revealed that the substituted F3 and I35 formed a sandwich structure with S45 and T47, which may enhance the overall structure rigidity with lowered RMSD values. This study verifies the efficiency of rational approach in thermostability improvement and provides a xylanase candidate of GH11 with great commercialization potential.

A xylanase gene of GH 10, Tlxyn10A, was cloned from Talaromyces leycettanus JCM12802 and expressed in Pichia pastoris. Purified recombinant TlXyn10A was acidic and hyperthermophilic, and retained stable over the pH range of 2.0-6.0 and at 90°C. Sequence analysis of TlXyn10A identified seven residues probably involved in substrate contacting. Three mutants (TlXyn10A&#95;P, &#95;N and &#95;C) were then constructed by substituting some or all of the residues with corresponding ones of hyperthermal Xyl10C from Bispora sp. MEY-1. TlXyn10A&#95;P with mutations at subsites +2 to +4 exhibited improved specific activity (by 0.44-fold) and pH stability (2.0-10.0). Molecular dynamics simulation analysis indicated that mutations E229I and F232E probably weaken the substrate affinity at subsites +3 to +4, and G149D may introduce a new hydrogen bond. These modifications altogether account for the improved performance of TlXyn10A&#95;P. Moreover, TlXyn10A&#95;P was able to hydrolyze wheat straw persistently, and has the application potentials in various industries., (Copyright © 2016. Published by Elsevier Ltd.)

Background: β-Glucanase is one of the most extensively used biocatalysts in biofuel, food and animal feed industries. However, the poor thermostability and low catalytic efficiency of most reported β-glucanases limit their applications. Currently, two strategies are used to overcome these bottlenecks, i.e., mining for novel enzymes from extremophiles and engineering existing enzymes., Results: A novel endo-β-1,3-1,4-glucanase of GH16 (Tlglu16A) from the thermophilic fungus Talaromyces leycettanus JCM12802 was produced in Pichia pastoris and characterized. For potential industrial applications, recombinant TlGlu16A exhibits favorable enzymatic properties over most reported glucanases, i.e., remarkable stability over a wide pH range from 1.0 to 10.0 and superior activity on glucan substrates (up to 15,197 U/mg). The only weakness of TlGlu16A is the thermolability at 65 °C and higher. To improve the thermostability, the enzyme thermal stability system was then used to engineer TlGlu16A through optimization of residual charge-charge interactions. Eleven mutants were constructed and compared to the wild-type TlGlu16A. Four mutants, H58D, E134R, D235G and D296K, showed longer half-life time at 80 °C (31, 7, 25, 22 vs. 0.5 min), and two mutants, D235G and D296K, had greater specific activities (158.2 and 122.2 %, respectively) and catalytic efficiencies (k cat/K m, 170 and 114 %, respectively)., Conclusions: The engineered TlGlu16A has great application potentials from the perspectives of enzyme yield and properties. Its thermostability and activity were apparently improved in the engineered enzymes through charge optimization. This study spans the genetic, functional and structural fields, and provides a combination of gene mining and protein engineering approaches for the systematic improvement of enzyme performance.

A xylanase gene of glycoside hydrolase family 10, GtXyn10, was cloned from Gloeophyllum trabeum CBS 900.73 and expressed in Pichia pastoris GS115. Purified recombinant GtXyn10 exhibited significant activities to xylan (100.0%), lichenan (11.2%), glucan (15.2%) and p-nitrophenol-β-cellobiose (18.6%), demonstrated the maximum xylanase and glucanase activities at pH 4.5-5.0 and 75°C, retained stability over the pH range of 2.0-7.5 and at 70°C, and was resistant to pepsin and trypsin, most metal ions and SDS. Multiple sequence alignment and modeled-structure analysis identified a unique Gly48 in GtXyn10, and site-directed mutagenesis of Gly48 to Lys improved the temperature optimum up to 80°C. Under simulated mashing conditions, GtXyn10 (80U) reduced the mash viscosity by 12.8% and improved the filtration rate by 31.3%. All these properties above make GtXyn10 attractive for potential applications in the feed and brewing industries., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In this study we investigated the antimicrobial activity of magnolol on Staphylococcus aureus. The minimal inhibitory concentrations of magnolol against 31 S. aureus strains ranged from 4-32 microg/mL. In addition, hemolysin assays, Western blotting, and real-time RT-PCR were performed to investigate the effect of magnolol on alpha-toxin secretion by both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA). The results indicated that sub-inhibitory concentrations of magnolol dose-dependently inhibited the transcription of hla (the gene encoding alpha-toxin) in S. aureus, resulting in a reduction of alpha-toxin secretion and, thus, hemolytic activities.