Site-directed display of zearalenone lactonase on spilt-intein functionalized nanocarrier for green and efficient detoxification of zearalenone.

In this study, we prepared a functional organic-inorganic hybrid nanoflower (InHNF) via split intein moiety in a biomineralization process without using organic solvents. InHNF could specifically bind the target enzymes from crude cell lysates within seconds and site-directedly display them on the surface by forming a peptide bond with enzyme's terminal amino acid residue. This unique feature enabled InHNF to increase the specific activity of zearalenone detoxifying enzyme ZHD518 by 40 âˆ¼ 60% at all tested temperatures and prevented enzyme denaturation even under extreme pH conditions (pH 3-11). Furthermore, it exhibited excellent operational stability, with a residual activity of over 70% after eight reaction cycles. Strikingly, InHNF-ZHD518 achieved above 50% ZEN degradation despite the near inactivation of free ZHD518 in beer sample. Overall, InHNF nanocarriers can achieve environmentally friendly, purification-free, and site-directed immobilization of food enzymes and enhance their catalytic properties, making them suitable for a wide range of industrial applications.

A Gibbs-INLA algorithm for multidimensional graded response model analysis.

In this paper, we propose a novel Gibbs-INLA algorithm for the Bayesian inference of graded response models with ordinal response based on multidimensional item response theory. With the combination of the Gibbs sampling and the integrated nested Laplace approximation (INLA), the new framework avoids the cumbersome tuning which is inevitable in classical Markov chain Monte Carlo (MCMC) algorithm, and has low computing memory, high computational efficiency with much fewer iterations, and still achieve higher estimation accuracy. Therefore, it has the ability to handle large amount of multidimensional response data with different item responses. Simulation studies are conducted to compare with the Metroplis-Hastings Robbins-Monro (MH-RM) algorithm and an application to the study of the IPIP-NEO personality inventory data is given to assess the performance of the new algorithm. Extensions of the proposed algorithm for application on more complicated models and different data types are also discussed.

Undergraduate Students' Profiles of Cognitive Load in Augmented Reality-Assisted Science Learning and Their Relation to Science Learning Self-efficacy and Behavior Patterns.

Research evidence indicated that a specific type of augmented reality-assisted (AR-assisted) science learning design or support might not suit or be effective for all students because students' cognitive load might differ according to their experiences and individual characteristics. Thus, this study aimed to identify undergraduate students' profiles of cognitive load in AR-assisted science learning and to examine the role of their distinct profiles in self-efficacy together with associated behavior patterns in science learning. After ensuring the validity and reliability of each measure, a latent profile analysis confirmed that 365 Chinese undergraduates carried diverse dimensions of cognitive load simultaneously. The latent profile analysis findings revealed four fundamental profiles: Low Engagement, Immersive, Dabbling, and Organized, characterized as carrying various respective cognitive loads. The multivariate analysis of variance findings revealed different levels of the six AR science learning self-efficacy dimensions across profiles. Low Engagement students displayed the lowest self-efficacy among all dimensions. Organized students recorded better conceptual understanding and higher-order cognitive skills than Dabbling ones. Students with the Immersive profile had the highest science learning self-efficacy. The lag sequential analysis results showed significant differences in behavior patterns among profiles. Among them, profiles with social interaction, test, and reviewing feedback behavior had a significantly higher score for self-efficacy than those patterns mainly based on test learning and resource visits. This finding provides a unified consideration of students' diverse profiles and can inform interventions for effective design of AR-assisted science learning to match appropriate strategies to facilitate the science learning effect.

Advances in health-promoting effects of natural polysaccharides: Regulation on Nrf2 antioxidant pathway.

Natural polysaccharides (NPs) possess numerous health-promoting effects, such as liver protection, kidney protection, lung protection, neuroprotection, cardioprotection, gastrointestinal protection, anti-oxidation, anti-diabetic, and anti-aging. Nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidant pathway is an important endogenous antioxidant pathway, which plays crucial roles in maintaining human health as its protection against oxidative stress. Accumulating evidence suggested that Nrf2 antioxidant pathway might be one of key regulatory targets for the health-promoting effects of NPs. However, the information concerning regulation of NPs on Nrf2 antioxidant pathway is scattered, and NPs show different regulatory behaviors in their different health-promoting processes. Therefore, in this article, structural features of NPs having regulation on Nrf2 antioxidant pathway are overviewed. Moreover, regulatory effects of NPs on this pathway for health-promoting effects are summarized. Furthermore, structure-activity relationship of NPs for health-promoting effects by regulating the pathway is preliminarily discussed. Otherwise, the prospects on future work for regulation of NPs on this pathway are proposed. This review is beneficial to well-understanding of underlying mechanisms for health-promoting effects of NPs from the view angle of Nrf2 antioxidant pathway, and provides a theoretical basis for the development and utilization of NPs in promoting human health.

The N-terminal hydrophobicity modulates a distal structural domain conformation of zearalenone lacton hydrolase and its application in protein engineering.

Zearalenone (ZEN) is one of the most common mycotoxins in maize, wheat, barley, sorghum, rye and other grains. ZEN contamination in feed is an international health issue due to its estrogenicity by competitively binding to estrogen receptors. Enzymatic detoxification of ZEN is superior to physical and chemical methods in terms of safety, environmental impact and preserving nutritional value and palatability, but is hampered by both the currently limited repertoire of detoxifying enzymes and the lack of knowledge about their structure-function relationships. In this study, a ZEN lacton hydrolase candidate (ZHD11C) was identified from thermo-tolerant Fonsecaea multimorphosa CBS 102226, and characterized to be more thermostable than these reported homologues. An intriguing feature of ZHD11C is that the N-terminal hydrophobicity affects its thermal stability and causes conformational change of a domain far from the N-terminal. This finding was successfully applied to enhance the thermostability of the most active ZEN lacton hydrolase ZHD518 through rationally tailoring its N-terminal hydrophobicity. Our results not only provide more insights into the structure-function relationships of ZEN lacton hydrolases, but generate better candidate for bio-decontamination of zearalenone in feed industries.

Recent developments on natural polysaccharides as potential anti-gastric cancer substance: Structural feature and bioactivity.

Gastric cancer (GC) is being a serious threat to human health. Seeking safer and more effective ingredients for anti-GC is of significance. Increasing natural polysaccharides (NPs) have been demonstrated to possess anti-GC activity. However, the information on anti-GC NPs is scattered. For well-understanding the potential of NPs as anti-GC substances, the recent developments on structure, bioactivity and mechanism of anti-GC NPs were comprehensively reviewed in this article. Meanwhile, the structure-activity relationship was discussed. Recent studies indicated that anti-GC NPs could be mainly divided into glucan and heteropolysaccharide, whose structures affected by sources and protocols of extraction and purification. NPs exhibited anti-GC activities in cell and animal experiments as well as clinical trials, and the mechanisms might be anti-proliferation, inducing apoptosis, anti-metastasis and anti-invasion, inducing autophagy, boosting immunity, anti-angiogenesis, reducing drug resistance, anti-angiogenesis, improving antioxidant level and changing metabolites. Moreover, structural features included molecular weight, functional groups, uronic acid and monosaccharide composition, glycosidic linkage type, and degree of branching and conformation might influence the activities. Otherwise, modifications could enhance the anti-GC activity of NPs, and anti-GC NPs could be combinedly used with chemotherapeutic drugs. This review supports the applications of NPs in anti-GC and provides theoretical basis for future study.

Phytochemicals, biological activity, and industrial application of lotus seedpod (Receptaculum Nelumbinis): A review.

Lotus (Nelumbo nucifera Gaertn.) is a well-known food and medicinal plant. Lotus seedpod (Receptaculum Nelumbinis) is the by-products during lotus products processing, which is considered as waste. Numerous studies have been conducted on its phytochemicals, biological activity and industrial application. However, the information on lotus seedpod is scattered and has been rarely summarized. In this review, summaries on preparation and identification of phytochemicals, the biological activities of extracts and phytochemicals, and applications of raw material, extracts and phytochemicals for lotus seedpod were made. Meanwhile, the future study trend was proposed. Recent evidence indicated that lotus seedpods extracts, obtained by non-organic and organic solvents, possessed several activities, which were influenced by extraction solvents and methods. Lotus seedpods were rich in phytochemicals categorized as different chemical groups, such as proanthocyanidins, oligomeric procyanidins, flavonoids, alkaloids, terpenoids, etc. These phytochemicals exhibited various bioactivities, including ameliorating cognitive impairment, antioxidation, antibacterial, anti-glycative, neuroprotection, anti-tyrosinase and other activities. Raw material, extracts and phytochemicals of lotus seedpods could be utilized as sources for biochar and biomass material, in food industry and as dye. This review gives well-understanding on lotus seedpod, and provides theoretical basis for its future research and application.

The complete chloroplast genome of Castanopsis carlesii (Hemsl.) Hay.

Castanopsis carlesii (Hemsl.) Hay. is a widely distributed and dominant tree species with significant ecological and economical values. In this study, the complete chloroplast genome sequence of C. carlesii was reported using the Illumina Hiseq 2500 platform. The complete chloroplast genome was 160,205 bp forming a typical quadripartite structure, with a pair of inverted repeated (IRs) regions of 25,670 bp, a large single copy (LSC) region of 89,849 bp, and a small single copy (SSC) region of 19,016 bp. A total of 124 functional genes were annotated, including 79 protein-coding genes, 37 tRNA genes, and eight rRNA genes. The ML phylogenetic analysis showed that the genus Castanopsis formed a clade except Castanopsis fargesii.