Identification and validation of core microbes for the formation of the characteristic flavor of fermented oysters (Crassostrea gigas).

Self-fermented oyster homogenates were prepared to investigate core microbes and their correlations with flavor formation mechanisms. Five bacterial and four fungal genera were identified. Correlation analysis showed that Saccharomyces cerevisiae, Kazachstania, and L. pentosus were core species for the flavor of fermented products. Four core microbes were selected for inoculation into homogenates. Twelve key aroma compounds with odor activity values >1 were identified by gas chromatography-mass spectrometry. L. plantarum and S. cerevisiae were beneficial for producing key aroma compounds such as 1-octen-3-ol, (E,Z)-2,6-nonadienal, and heptanal. Fermentation with four microbes resulted in significant increases in contents of Asp, Glu, Lys, inosine monophosphate, and guanosine monophosphate, which provided freshness and sweetness. Fermentation with four microbes resulted in high digestibility, antioxidant abilities, and zinc contents. This study has elucidated the mechanism of flavor formation by microbial action and provides a reference for targeted flavor control in fermented oyster products.

Drought-induced circular RNAs in maize roots: separating signal from noise.

Circular RNAs (CircRNAs) play an important role in diverse biological processes; however, their origin and functions, especially in plants, remain largely unclear. Here, we used two maize (Zea mays) inbred lines, as well as 14 of their derivative RILs with different drought sensitivity, to systematically characterize 8,790 circRNAs in maize roots under well-watered (WW) and water-stress (WS) conditions. We found that a diverse set of circRNAs expressed at significantly higher levels under WS. Enhanced expression of circRNAs was associated with longer flanking introns and an enrichment of long interspersed nuclear element (LINE) retrotransposable elements. The epigenetic marks found at the back-splicing junctions of circRNA-producing genes were markedly different from canonical splicing, characterized by increased levels of H3K36me3/H3K4me1, as well as decreased levels of H3K9Ac/H3K27Ac. We found that genes expressing circRNAs are subject to relaxed selection. The significant enrichment of trait-associated sites along their genic regions suggested that genes giving rise to circRNAs were associated with plant survival rate under drought stress, implying that circRNAs play roles in plant drought responses. Furthermore, we found that overexpression of circMED16, one of the drought-responsive circRNAs, enhances drought tolerance in Arabidopsis (Arabidopsis thaliana). Our results provide a framework for understanding the intricate interplay of epigenetic modifications and how they contribute to the fine-tuning of circRNA expression under drought stress.

A Recombinant Alginate Lyase Algt1 with Potential in Preparing Alginate Oligosaccharides at High-Concentration Substrate.

Alginate lyase has been demonstrated as an efficient tool in the preparation of functional oligosaccharides (AOS) from alginate. The high viscosity resulting from the high concentration of alginate poses a limiting factor affecting enzymatic hydrolysis, particularly in the preparation of the fragments with low degrees of polymerization (DP). Herein, a PL7 family alginate lyase Algt from Microbulbifer thermotolerans DSM 19189 was developed and expressed in Pichia pastoris. The recombinant alginate lyase Algt1 was constructed by adopting the structural domain truncation strategy, and the enzymatic activity towards the alginate was improved from 53.9 U/mg to 212.86 U/mg compared to Algt. Algt1 was stable when incubated at 40 °C for 90 min, remaining with approximately 80.9% of initial activity. The analyses of thin-layer chromatography (TLC), fast protein liquid chromatography (FPLC), and electrospray ionization mass spectrometry (ESI-MS) demonstrated that the DP of the minimum identifiable substrate of Algt1 was five, and the main hydrolysis products were AOS with DP 1-4. Additionally, 1-L the enzymatic hydrolysis system demonstrated that Algt1 exhibited an effective degradation at alginate concentrations of up to 20%, with the resulting products of monosaccharides (14.02%), disaccharides (21.10%), trisaccharides (37.08%), and tetrasaccharides (27.80%). These superior properties of Algt1 make it possible to efficiently generate functional AOS with low DP in industrial processing.

Identification and Functional Analysis of Drought-Responsive Long Noncoding RNAs in Maize Roots.

Long noncoding RNAs (lncRNAs) are transcripts with lengths of more than 200 nt and limited protein-coding potential. They were found to play important roles in plant stress responses. In this study, the maize drought-tolerant inbred line AC7643 and drought-sensitive inbred line AC7729/TZSRW, as well as their recombinant inbred lines (RILs) were selected to identify drought-responsive lncRNAs in roots. Compared with non-responsive lncRNAs, drought-responsive lncRNAs had different sequence characteristics in length of genes and number of exons. The ratio of down-regulated lncRNAs induced by drought was significantly higher than that of coding genes; and lncRNAs were more widespread expressed in recombination sites in the RILs. Additionally, by integration of the modifications of DNA 5-methylcytidine (5mC), histones, and RNA N6-methyladenosine (m6A), it was found that the enrichment of histone modifications associated with transcriptional activation in the genes generated lncRNAs was lower that coding genes. The lncRNAs-mRNAs co-expression network, containing 15,340 coding genes and 953 lncRNAs, was constructed to investigate the molecular functions of lncRNAs. There are 13 modules found to be associated with survival rate under drought. We found nine SNPs located in lncRNAs among the modules associated with plant survival under drought. In conclusion, we revealed the characteristics of lncRNAs responding to drought in maize roots based on multiomics studies. These findings enrich our understanding of lncRNAs under drought and shed light on the complex regulatory networks that are orchestrated by the noncoding RNAs in response to drought stress.

TrichomeYOLO: A Neural Network for Automatic Maize Trichome Counting.

Plant trichomes are epidermal structures with a wide variety of functions in plant development and stress responses. Although the functional importance of trichomes has been realized, the tedious and time-consuming manual phenotyping process greatly limits the research progress of trichome gene cloning. Currently, there are no fully automated methods for identifying maize trichomes. We introduce TrichomeYOLO, an automated trichome counting and measuring method that uses a deep convolutional neural network, to identify the density and length of maize trichomes from scanning electron microscopy images. Our network achieved 92.1% identification accuracy on scanning electron microscopy micrographs of maize leaves, which is much better performed than the other 5 currently mainstream object detection models, Faster R-CNN, YOLOv3, YOLOv5, DETR, and Cascade R-CNN. We applied TrichomeYOLO to investigate trichome variations in a natural population of maize and achieved robust trichome identification. Our method and the pretrained model are open access in Github (https://github.com/yaober/trichomecounter). We believe TrichomeYOLO will help make efficient trichome identification and help facilitate researches on maize trichomes.

Novel Peptide from the Hydrolysate of Hybrid Sturgeon (Acipenseridae) Spinal Cord: Isolation, Identification, and Anti-proliferative Effects in Human Cervix Cancer Cells.

Anti-proliferative peptides have recently attracted attention for their excellent bioactivity and biocompatibility. In this paper, five novel anti-proliferative peptides were identified from the hydrolysate of hybrid sturgeon spinal cord (HSSC). In addition, the structure-activity relationship of the novel anti-proliferative peptides was explored. In vitro experiments indicated that the peptide "VDSVLDVVRK" presented the highest inhibition of HeLa cell growth in all samples (IC50 = 2.5 µM). VDSVLDVVRK showed a random coil secondary structure and nanomicelles in the tumor microenvironment. Transmission electron microscopy results confirmed that nanomicelles disassemble as the concentration of VDSVLDVVRK decreases. Furthermore, VDSVLDVVRK could induce HeLa cell apoptosis by increasing the expression of Cyt-c (98.65 ± 1.85%, p < 0.01) and caspase-9 (39.85 ± 1.81%, p < 0.01). In this study, the anti-proliferative mechanism of the HSSC peptide was discussed, which provided a theoretical basis for the research and development of anti-proliferative functional food.

Effects of non-pharmacological interventions on youth with internet addiction: a systematic review and meta-analysis of randomized controlled trials.

Objective: To assess the overall effectiveness of non-pharmacological interventions on internet addiction (IA) in youth. Method: Randomized controlled trials (RCTs) published from their inception to April 1, 2023 were searched in Cochrane, Embase, Medline, Web of Science, China National Knowledge Infrastructure, China Science and Technology Journal Database, Chinese BioMedical Literature Database, and WanFang Data. Two reviewers independently extracted data and evaluated bias using the Cochrane Risk of Bias tool. Results: Sixty-six studies performed from 2007 to 2023, with a total of 4,385 participants, were identified. The NPIs included group counseling, cognitive behavioral therapy, sports intervention, combined interventions, eHealth, educational intervention, positive psychology intervention, sand play intervention, and electrotherapy. The results revealed that NPIs significantly reduced IA levels (standardized mean difference, SMD: -2.01, 95% confidence interval, CI: -2.29 to -1.73, I2 = 93.0%), anxiety levels (SMD: -1.07, 95%CI: -1.41 to -0.73, I2 = 72.4%), depression levels (SMD: -1.11, 95%CI: -1.52 to -0.7, I2 = 84.3%), and SCL-90 (SMD: -0.75, 95%CI: -0.97 to -0.54, I2 = 27.7%). Subgroup analysis stratified by intervention measure showed that cognitive behavioral therapy, group counseling, sports intervention, combined intervention, educational intervention, positive psychology intervention, sandplay intervention, and mobile health were all effective in relieving symptoms of IA except electrotherapy. Conclusion: NPIs appear to be effective in the treatment of IA in youth, which would act as an alternative treatment of IA. Further studies with larger sample sizes and robust designs are needed.

Impact of COVID-19 Pandemic Perception on Job Stress of Construction Workers.

Construction has been regarded as one of the most stressful industries, and the COVID-19 pandemic has deteriorated this situation. This research developed and tested a model of the impact of COVID-19 pandemic perception on job stress of construction workers. Both problem-focused and emotion-focused coping were considered as mediators. Empirical data were collected using a detailed questionnaire from the Chinese construction industry. The results showed that pandemic perception was significantly related to psychological and physical stress. Emotion-focused coping was mainly triggered by pandemic fear and job insecurity, while problem-focused coping was mainly triggered by organizational pandemic response. Furthermore, the effects of pandemic fear and organizational pandemic response on job stress were mediated by problem-focused coping. Finally, the theoretical and practical significance, research limitations, and future research directions of this study are discussed.

Demographic Influences on Perceived Stressors of Construction Workers during the COVID-19 Pandemic.

Construction work is one of the most stressful occupations in the world, and the COVID-19 pandemic has only exacerbated this reality. This research conducted a detailed investigation on the perceived stressors of different demographic groups among construction workers. Empirical data were collected using a structured questionnaire in the Chinese construction industry. The empirical data were processed using both an independent sample t-test and an Analysis of Variance (ANOVA). The findings indicated that male workers reported greater workloads than did females. Married workers experienced more pandemic fear and job insecurity, and they were more sensitive to the poor working environment. Highly-educated workers were inclined to be more satisfied with organizational pandemic responses, and had lower job insecurity and role ambiguity, but they experienced heavier workloads. In addition, the differences in work experience and age were statistically significant with regards to job insecurity. This research contributes to the body of knowledge by giving a comprehensive understanding of demographic influences on perceived stressors among construction workers. It also provides valuable insights to identify sensitive demographic groups and promote their health and wellbeing during and after the pandemic.

Effects of freeze-drying and spray-drying on the physical and chemical properties of Perinereis aibuhitensis hydrolysates: Sensory characteristics and antioxidant activities.

This work was to investigate the impact of drying on the physical, chemical stability and character properties of P. aibuhitensis hydrolysate. Properties including amino acid composition, color stability, molecular weight distribution, powder morphology, etc. were compared between the freeze drying powder (FD) and spray drying powder (SD). They were fractionated with ultra filtration in antioxidant activities test. FD and SD contained amounts of amino acids and umami amino acids. SD exhibited the higher lightness and whiteness. SD had more compounds between 451 Da and 6511 Da. The surface morphology of FD was porous and flaky while SD was microsphere. SD had more volatile flavor substances and higher antioxidant activities on DPPH, hydroxyl, and superoxide radical-scavenging. In summary, results demonstrated that drying methods indeed affected the characteristics of hydrolysate, and the one prepared by spray drying method had the potential to be utilized for antioxidant food development and seafood seasoning.

Chemical and quality evaluation of Pacific white shrimp Litopenaeus vannamei: Influence of strains on flesh nutrition.

The Pacific white shrimp, Litopenaeus vannamei, is an important fisheries resource in China. To investigate the differences in nutritional quality among strains, we analyzed and compared the basic muscle nutritional components, amino acid (hydrolyzed and free) compositions, and fatty acid compositions among four L. vannamei strains (Universal, KH-1, Syaqua, and common). The result showed that under an efficiency aquaculture model, all four strains had high protein (21.1%-22.3%) and low fat (0.8%-1.1%). The Universal strain was highest in protein and fat as well as essential amino acid score (147.97). The Syaqua strain had the highest levels of polyunsaturated fatty acids (44.88%). The KH-1 strain had the highest free amino acid content (2.68%), which contributes to the taste. Our findings revealed that strain-specific variability exists in chemical composition of the shrimp L. vannamei under controlled condition, which may provide buying reference for consumers.

Maize DNA Methylation in Response to Drought Stress Is Involved in Target Gene Expression and Alternative Splicing.

DNA methylation is important for plant growth, development, and stress response. To understand DNA methylation dynamics in maize roots under water stress (WS), we reanalyzed DNA methylation sequencing data to profile DNA methylation and the gene expression landscape of two inbred lines with different drought sensitivities, as well as two of their derived recombination inbred lines (RILs). Combined with genotyping-by-sequencing, we found that the inheritance pattern of DNA methylation between RILs and parental lines was sequence-dependent. Increased DNA methylation levels were observed under WS and the methylome of drought-tolerant inbred lines were much more stable than that of the drought-sensitive inbred lines. Distinctive differentially methylated genes were found among diverse genetic backgrounds, suggesting that inbred lines with different drought sensitivities may have responded to stress in varying ways. Gene body DNA methylation showed a negative correlation with gene expression but a positive correlation with exon splicing events. Furthermore, a positive correlation of a varying extent was observed between small interfering RNA (siRNA) and DNA methylation, which at different genic regions. The response of siRNAs under WS was consistent with the differential DNA methylation. Taken together, our data can be useful in deciphering the roles of DNA methylation in plant drought-tolerance variations and in emphasizing its function in alternative splicing.

A natural antisense transcript acts as a negative regulator for the maize drought stress response gene ZmNAC48.

Although plant-specific NAC transcription factors play crucial roles in response to abiotic stress, few reports describe the regulation of NAC genes in maize (Zea mays) by the cis-natural antisense transcripts (cis-NATs). In this study, 521 NAC genes from Gramineae were classified, of which 51 NAC genes contained cis-NATs. ZmNAC48 and cis-NATZmNAC48 co-localized to the same cell nucleus, and both transcripts responded to drought stress. Arabidopsis plants overexpressing ZmNAC48 had improved drought tolerance, lower rate of water loss, enhanced stomatal closure, and higher rates of survival. Transient expression in both maize protoplasts and tobacco leaves indicated that cis-NATZmNAC48 reduced ZmNAC48 expression. Western blotting and ribosome profiling analyses confirmed that cis-NATZmNAC48 lacked protein coding potential. Furthermore, the cis-NAT-derived small-interfering RNAs (nat-siRNAs) generated from the overlapping regions of ZmNAC48 and cis-NATZmNAC48 were detected in maize and transgenic Arabidopsis. Cis-NATZmNAC48 overexpressing maize showed higher water loss rate, increased stomatal opening, and had more dead leaves. Expression of ZmNAC48 and nat-siRNA was decreased in these plants. Taken together, our study indicates that both ZmNAC48 and cis-NATZmNAC48 are involved in plant drought stress responses, and that the double-stranded RNA-dependent mechanism is involved in the interaction between cis-NATZmNAC48 and ZmNAC48. Additionally, cis-NATZmNAC48 may negatively regulate ZmNAC48 to affect stomatal closure of maize.

Development of alginate hydrogel/gum Arabic/gelatin based composite capsules and their application as oral delivery carriers for antioxidant.

We have designed microcapsules-immobilized composite capsules and evaluated the oral delivery efficacy. The composite capsules were developed by encapsulating Perinereis aibuhitensis extract (PaE), a model substance possessing antioxidant activity, loaded gum Arabic/gelatin microcapsules in calcium alginate (CA) hydrogel (PaE:CA/GA/GE-CCs). In vitro antioxidant assay showed the obtained composite capsules were able to protect PaE from gastric acid, since O2- scavenging rate of encapsulated PaE was about 1.8 folds as that of free PaE after 5 h incubation in simulated gastrointestinal fluid. Moreover, in vivo study showed that after the treatment of oral administration for 30 days, the mice of PaE:CA/GA/GE-CCs group suffered significantly lower oxidative stress level than those of other groups, illustrated as higher SOD and catalase activity, as well as lower malondialdehyde content in liver cells. The results demonstrated the composite capsules could concentrate PaE in small intestine, and enhance the absorption efficiency and in vivo efficacy.

Genome-Wide Association Study of 13 Traits in Maize Seedlings under Low Phosphorus Stress.

CORE IDEAS: Low P stress is a global issue for grain production. Significant phenotypic differences were detected among 13 traits in 356 maize lines under P-sufficient and P-deficient conditions. Significant single nucleotide polymorphisms (SNPs) and low-P stress-responsive genes were identified for 13 maize root traits based on a genome-wide association study. Hap5, harboring 12 favorable SNPs, could enhance strong root systems and P absorption under low-P stress. Phosphorus is an essential macronutrient required for normal plant growth and development. Determining the genetic basis of root traits will enhance our understanding of maize's (Zea mays L.) tolerance to low-P stress. Here, we identified significant phenotypic differences for 13 traits in maize seedlings subjected to P-sufficient and P-deficient conditions. Six extremely sensitive and seven low-P stress tolerant inbreds were selected from 356 inbred lines of maize. No significant differences were observed between temperate and tropical-subtropical groups with respect to trait ratios associated with the adaptation to low-P stress. The broad-sense heritability of these traits ranged from relatively moderate (0.59) to high (0.90). Through genome-wide association mapping with 541,575 informative single nucleotide polymorphisms (SNPs), 551, 1140 and 1157 significant SNPs were detected for the 13 traits in 2012, 2016 and both years combined, respectively, along with 23 shared candidate genes, seven of which overlapped with reported quantitative trait loci and genes for low-P stress. Five haplotypes located in candidate gene GRMZM2G009544 were identified; among these, Hap5, harboring 12 favorable SNP alleles, showed significantly greater values for the root traits studied than the other four haplotypes under both experimental conditions. The candidate genes and favorable haplotypes and alleles identified here provide promising resources for genetic studies and molecular breeding for improving tolerance to abiotic stress in maize.

An efficient mercapto-functionalized organic-inorganic hybrid sorbent for selective separation and preconcentration of antimony(iii) in water samples.

This work reported on the application of mercapto-functionalized silica-supported organic-inorganic hybrid sorbent as a solid phase extraction (SPE) extractant for effective separation and preconcentration of Sb(iii) species in real water samples. The influences of pH, sorbent amounts, flow rates and the concentration of eluent on the adsorption and desorption of Sb(iii) species had been evaluated. The recovery of Sb(iii) species at pH 5 with 100 mg mercapto-functionalized hybrid sorbent at the flow rate of 5.0 mL min-1 was greater than 95% without interference from all of metal ions tested. The trapped Sb(iii) species by extractant was then eluted with 5% HCl solution at the flow rate of 5.0 mL min-1. The proposed procedure permitted large enrichment factors of about 200 and higher for 10 µg L-1 of Sb(iii) species. The merits of analytical figures for the determination of Sb(iii) species were as follows: detection limit (3σ, n = 11), 2 ng L-1; precision, 1.6% (n = 11) for 10 µg L-1 of Sb(iii) species; the linear calibration curve presented in the concentration range of 1.0-200.0 µg L-1. The validity of the proposed procedure was checked by the analysis of standard reference materials. Excellent agreement between the analytical results and the certified values (t-test at 95% confidence level) was found. The mercapto-functionalized hybrid sorbent as a SPE extractant was applied to the determination of Sb(iii) species in various water samples with satisfactory results.

Effects of HMW-GS Ax1 or Dx2 absence on the glutenin polymerization and gluten micro structure of wheat (Triticum aestivum L.).

Wheat (Triticum aestivum L.) dough strength and extensibility are mainly determined by the polymerization of glutenin. The number of high-molecular-weight glutenin subunits (HMW-GS) differs in various wheat varieties due to the silencing of some genes. The effects of Ax1 or Dx2 subunit absence on glutenin polymerization, dough mixing properties and gluten micro structure were investigated with two groups of near-isogenic lines. The results showed that Ax1 or Dx2 absence decreased the accumulation rate of glutenin polymers and thus delayed the rapid increase period for glutenin polymerization by at least ten days, which led to lower percentage of polymeric protein in mature grain. Ax1 or Dx2 absence significantly decreased the dough development time and dough stability, but increased the uniformity of micro structure. Lacunarity, derived from quantitative analysis of gluten network, is suggested as a new indicator for wheat quality.

Preparation and antithrombotic activity identification of Perinereis aibuhitensis extract: a high temperature and wide pH range stable biological agent.

In this work, a thermal and wide pH range (from 1 to 13) stable biological agent was extracted from Perinereis aibuhitensis (P. aibuhitensis), and the antithrombotic activity of this P. aibuhitensis extract (PaE) was investigated. In vitro antithrombotic activity test indicated that PaE could significantly extend the clotting time of recalcified rabbit blood: the clotting time of the 10 mg mL-1, 20 mg mL-1 and 40 mg mL-1 PaE groups increased by 24.24%, 68.64% and 130.76%, respectively. Further platelet poor plasma (PPP) coagulation study proved that PaE could obviously inhibit the intrinsic coagulation pathway and slightly inhibit the extrinsic coagulation pathway. Moreover, PaE could effectively inhibit fibrinogen turning into fibrin induced by thrombin. More importantly, PaE exhibited thermal stability, since P. aibuhitensis was boiled in the PaE preparation process, as well as tolerance to strong acid and alkali, since its fibrinogen inhibition activity was retained after treatment with a wide range of pH value conditions. Finally, the antithrombotic activity ingredients in PaE were preliminarily identified, the results of which indicated that the ingredients were ethanol insoluble, insensitive to papain and pepsin, and could be degraded by H2O2. Additionally, we demonstrated that PaE at a concentration of not more than 20 mg mL-1, the concentration at which PaE showed high anticoagulant activity, exhibited favorable biocompatibility via in vitro hemolysis rate test and MTT assay. In summary, the results evidenced that this conveniently prepared and stable PaE was a safe and effective antithrombotic agent, and had the potential to be utilized for antithrombotic food development.

Influence of high-molecular-weight glutenin subunit composition at Glu-A1 and Glu-D1 loci on secondary and micro structures of gluten in wheat (Triticum aestivum L.).

As one of critical gluten proteins, high-molecular-weight glutenin subunits (HMW-GS) mainly affect the rheological behaviour of wheat dough. The influence of HMW-GS variations at the Glu-A1 and Glu-D1 loci on both secondary and micro structures of gluten and rheological properties of wheat dough was investigated in this study. Results showed that the Amide I bands of the three near-isogenic lines (NILs) shifted slightly, but the secondary structures differed significantly. The micro structure of gluten in NIL 4 (Ax null) showed bigger apertures and less connection, compared to that in Xinong 1330 (Ax1). The micro structure of gluten in NIL 5 (Dx5+Dy10) showed more compact than that in Xinong 1330 (Dx2+Dy12). Correlation analysis demonstrated that the content of ß-sheets and disulfide bonds in gluten has a significant relationship with dough properties. The secondary structures of native gluten are suggested to be used as predictors of wheat quality.