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The Poyang Lake Basin (PLB) has a long-standing history of drought, which has been intensified by global warming, posing significant risks to water security and agriculture. However, the specific patterns of drought, particularly seasonal variations, remain poorly understood, making it crucial to investigate these dynamics for effective water management and resilience planning. We employed calibrated SWAT model to simulate monthly soil moisture in five sub-basins to analyze drought characteristics across the PLB over the past six decades. A Multivariate Standardized Drought Index (MSDI) was then developed with simulated Standardized Soil Moisture Index (SSI) and Standardized Precipitation Index (SPI) based on copula functions. We found that (1) The SWAT can simulate monthly streamflow well with NS being 0.76–0.92 for validation data over the sub-basins in the PLB. (2) The MSDI index indicated that there were more drought events during 1960–1979 and 2000–2019, highlighting a cyclical pattern of drought events in the PLB. (3) The Xiushui River Basin encountered the most extreme drought conditions since 2000, indicating the basin faced a high risk of dry conditions. Additionally, our wavelet period analysis showed an increase in drought frequency after the year 2000, with less distinct periodicity. These findings contribute to our understanding of drought dynamics in the Poyang Lake Basin and offer valuable insights for developing sustainable water resource management and climate adaptation strategies in the region.

ABSTRACT Mountains have been recognized as biodiversity hotspots and possess strong elevational gradients. Whether these gradients exhibit similar characteristics in the multidimensional diversity patterns across different mountain ranges is a subject of inquiry. Exploring the elevational patterns of the diversity and phylogenetic information of plant species in the different subtropical mountains is necessary. Here, we compiled the elevational patterns of plant diversity occurring in the eight subtropical mountains of China and focused on the assessment of the patterns and determinants of the multi‐dimensional diversity and phylogenetic structure in different mountains. We also detected the elevational patterns and their relationship between different groups. The results indicate two main patterns of multi‐dimensional diversity: monotonic decrease and hump‐shaped, along with the area effect on the species diversity. There is a strong positive link between the non‐native and native species of species richness, and significant differences in phylogenetic structure's elevational distribution. We did not find the same rule in the mountains that the plant species in the lowlands indicate phylogenetic overdispersion, and the species in the higher elevation regions indicate phylogenetic clustering. We found that the plants' diversity peak is related to the mountains size, and this result showed that we should pay more attention to the conservation of plant communities in the higher elevation regions for the higher mountains. This study suggested that we should take different protective measures for the subtropical mountains: the lowland regions should be paid more attention in Mt. Lushan (LS), Mt. Guanshan (GS), Mt. Huanggang (HG), and Mt. Fanjing (FJ), and the middle‐altitude regions should be of concern for other mountains. This study helps to better understand the elevational gradients of species diversity on different scales and provides supporting scientific basis for biodiversity conservation in the subtropical mountain regions.

The liquid-liquid extraction method using reverse micelles can simultaneously extract lipid and protein of oilseeds, which have become increasingly popular in recent years. However, there are few studies on mass transfer processes and models, which are helpful to better control the extraction process of oils and proteins. In this paper, mass transfer process of peanut protein extracted by bis(2-ethylhexyl) sodium sulfosuccinate (AOT)/isooctane reverse micelles was investigated. The effects of stirring speed (0, 70, 140, and 210 r/min), temperature of extraction (30, 35, 40, 45, and 50 °C), peanut flour particle size (0.355, 0.450, 0.600, and 0.900 mm) and solid-liquid ratio (0.010, 0.0125, 0.015, 0.0175, and 0.020 g/mL) on extraction rate were examined. The results showed that extraction rate increased with temperature rising, particle size reduction as well as solid-liquid ratio increase respectively, while little effect of stirring speed (P > 0.05) was observed. The apparent activation energy of extraction process was calculated as 10.02 kJ/mol and Arrhenius constant (A) was 1.91 by Arrhenius equation. There was a linear relationship between reaction rate constant and the square of the inverse of initial particle radius (1/r02) (P

Vegetation is a fundamental component of terrestrial ecosystems, and accurately assessing the effects of seasonal climate variations, extreme weather events, and land use changes on vegetation dynamics is crucial. The Ganjiang River Basin (GRB), a key region for water conservation and recharge in southeastern China, has experienced significant land use changes and variable climate in the past. However, comprehensive evaluations of how these changes have impacted vegetation remain limited. To address this gap, we used machine learning models (random forest and XGBoost) to assess the impact of seasonal and extreme climate variables, land cover, topography, soil properties, atmospheric CO2, and night-time light intensity on vegetation dynamics. We found that the annual mean NDVI showed a slight increase from 1990 to 1999 but has decreased significantly over the last 8 years. XGBoost was better than the RF model in simulating the NDVI when using all five types of data source (R2 = 0.85; RMSE = 0.04). The most critical factors influencing the NDVI were forest and cropland ratio, followed by soil organic carbon content, elevation, cation exchange capacity, night-time light intensity, and CO2 concentration. Spring minimum temperature was the most important seasonal climate variable. Both linear and nonlinear relationships were identified between these variables and the NDVI, with most variables exhibiting threshold effects. These findings underscore the need to develop and implement effective land management strategies to enhance vegetation health and promote ecological balance in the region.

Monascus, a genus of fungi known for its fermentation capability and production of bioactive compounds, such as Monascus azaphilone pigments and Monacolin K, have received considerable attention because of their potential in biotechnological applications. Understanding the genetic basis of these metabolic pathways is crucial for optimizing the fermentation and enhancing the yield and quality of these products. However, Monascus spp. are not model fungi, and knowledge of their genetics is limited, which is a great challenge in understanding physiological and biochemical phenomena at the genetic level. Since the first application of particle bombardment to explore gene function, it has become feasible to link the phenotypic variation and genomic information on Monascus strains. In recent decades, accurate gene editing assisted by genomic information has provided a solution to analyze the functions of genes involved in the metabolism and development of Monascus spp. at the molecular level. This review summarizes most of the genetic manipulation tools used in Monascus spp. and emphasizes Agrobacterium tumefaciens-mediated transformation and nuclease-guided gene editing, providing comprehensive references for scholars to select suitable genetic manipulation tools to investigate the functions of genes of interest in Monascus spp.

The effects of three dietary oils (rapeseed oil, camellia oil, linseed oil) with different fatty acid compositions on the growth performance, digestion and gut microbiota of SD rats after 8 weeks of feeding were studied. The serum metabolic index and liver histomorphology of rats were measured using an automatic biochemical analyzer and light microscope. Furthermore, 16S rDNA amplicon sequencing technology was used to analyze the gut microbiota. It was found that these differences in fatty acid composition had no significant effect on body fat and liver tissue. However, after digestion, the rapeseed oil group showed lowest triglyceride content (1.22 ± 0.15) and a lower LDL/HDL ratio (0.41 ± 0.02). For gut microbiota distribution, the linseed oil group showed a higher Firmicutes/Bacteroides ratio (6.11 ± 0.54) and a high proportion of Lactobacillus. These data indicate that both the unsaturated fatty acid content and n-3 unsaturated fatty acids collectively had an effect on digestion metabolism, and the influence order may be n-3 unsaturated fatty acids > unsaturated fatty acid content.

Near-infrared hyperspectral imaging combined with partial least regression (PLSR) models for rapid and non-destructive detection of beef adulterated with pea protein was investigated. The adulteration samples were prepared by mixing pea protein into minced beef with a concentration gradient of 1%~30% (w/w) (interval of 1%), and a total of 93 samples were finally obtained to collect spectral information. After preprocessed by five methods including moving average smoothing (MAS), Gaussian filter smoothing (GFS), baseline correction (BC), Savitzky Golay convolution smoothing (SGCS), and standard normal variable correction (SNV), the spectra were used to construct prediction models by using PLSR algorithm. The regression coefficient (RC), stepwise and successive projections algorithm (SPA) were then used to select optimal wavelength for model optimization. The results showed that the full-band PLSR model constructed by GFS spectra had better prediction performance (R2P=0.87, RMSEP=3.22%, ΔE=1.82, RPD=5.82). The 24 optimal wavelengths including 908.8, 913.7, 918.7, 928.5, 936.8, 945.0, 961.5, 971.3, 994.4, 1017.4, 1033.9, 1099.7, 1135.8, 1167.1, 1196.7, 1211.5, 1453.6, 1549.3, 1607.1, 1633.7, 1660.1, 1678.4, 1683.4 and 1686.7 nm were selected by RC method from the GFS spectra and the original PLSR model optimized with these wavelengths showed better performance (R2P=0.90, RMSEP=2.85%, ΔE=1.13, RPD=6.19). In conclusion, it was possible to use hyperspectral imaging to achieve rapid and non-destructive detection of beef adulterated with pea protein.

IntroductionAs a renewable forest resource, bamboo plays a role in sustainable forest development. However, traditional cutting systems, selection cutting (SeC) and clear-cutting (ClC), result in an unsustainable production of bamboo forests due to labor-consuming or bamboo degradation. Recently, a strip clear-cutting (StC) was theoretically proposed to promote the sustainability of bamboo production, while little is known about its application consequence.MethodsBased on a 6-year experiment, we applied the strip clear-cutting system in a typical running bamboo (Phyllostachys glauca McClure) forest to assess its feasibility and sustainability. Using SeC and ClC as controls, we set three treatments with different strip widths (5 m, 10 m, and 20 m) for strip clear-cutting, simplified as StC-5, StC-10, and StC-20, respectively. Then, we investigated leaf physiological traits, bamboo size and productivity, population features, and economic benefits for all treatments.ResultsThe stands managed by StC had high eco-physiological activities, such as net photosynthetic rate (Pn), photosynthetic nitrogen use efficiency (PNUE), and photosynthetic phosphorus use efficiency (PPUE), and thus grew well, achieved a large diameter at breast height (DBH), and were tall. The stand biomass of StC (8.78 t hm-2 year-1) was 1.19-fold and 1.49-fold greater than that of SeC and ClC, respectively, and StC-10 and StC-20 were significantly higher than SeC or ClC (p< 0.05). The income and profit increased with the increase in stand density and biomass, and StC-20 and StC-10 were significantly higher than SeC or ClC (p< 0.05). Using principal components analysis and subordinate function analysis, we constructed a composite index to indicate the sustainability of bamboo forests. For the sustainability assessment, StC-10 had the highest productive sustainability (0.59 ± 0.06) and the second highest economic sustainability (0.59 ± 0.11) in all cutting treatments. StC-10 had the maximum overall sustainability, with a value of 0.53 ± 0.02, which was significantly higher than that of ClC (p< 0.05).ConclusionThe results verified that StC for Phyllostachys glauca forests is feasible and sustainable as its sustainability index outweighs those of traditional cutting systems (SeC and ClC), and 10 m is the optimum distance for the strip width of StC. Our findings provide a new cutting system for managing other running bamboo forests sustainably.

Global climate change can affect tree growth and carbon sink function by influencing plant carbohydrate synthesis and utilization, while elevation can be used as an ideal setting under natural conditions to simulate climate change effects. The effect of elevation on tree growth may depend on organ type. However, the allocation patterns of nonstructural and structural carbohydrates (NSCs and SCs, respectively) in different tree organs and their response to elevation remain unclear. We selected four dominant tree species, Schima superba, Castanopsis eyrei, Castanopsis fargesii and Michelia maudiae, along an elevation gradient from 609 to 1,207 ​m in subtropical evergreen broad-leaved forests and analyzed leaf, trunk, and fine root NSCs, carbon (C), nitrogen (N) and phosphorus (P) concentrations and the relative abundance of SCs. Leaf NSCs increased initially and then decreased, and trunk NSCs increased with increasing elevation. However, root NSCs decreased with increasing elevation. The relative abundance of SCs in leaves and trunks decreased, while the relative abundance of root SCs increased with increasing elevation. No significant correlations between SCs and NSCs in leaves were detected, while there were negative correlations between SCs and NSCs in trunks, roots, and all organs. Hierarchical partitioning analysis indicated that plant C/N and C/P were the main predictors of changes in SCs and NSCs. Our results suggest that tree organs have divergent responses to elevation and that increasing elevation will inhibit the aboveground part growth and enhance the root growth of trees. A tradeoff between the C distribution used for growth and storage was confirmed along the elevation gradient, which is mainly manifested in the “sink” organs of NSCs. Our results provide insight into tree growth in the context of global climate change scenarios in subtropical forest ecosystems.

Soil C:N:P stoichiometry can regulate plant survival and reflect soil fertility and nutrient utilization. Despite the widespread conversion of old-growth forests to plantations or secondary forests, there is little knowledge about how these conversions affect the relation between leaf and soil stoichiometries. We examined the topography, leaf, and soil stoichiometries of 75 plots (20 m × 20 m) across Chinese fir plantations, secondary forests, and old-growth forests in subtropical China. We found that: (1) There were significant differences in leaf carbon, nitrogen, phosphorus, and their stoichiometry ratios among different stand types (2) stand type significantly affected soil SOC, TP, C:N, C:P, and N:P, except TN and (3) the explanation percentage of leaf stoichiometry on soil stoichiometry doubled with the conversion of old-growth forest to Chinese fir plantation, whereas it was twofold decreased with the conversion of old-growth forest to secondary forest. The explanation percentage of topography on soil stoichiometry decreased onefold at a minimum with the conversion of the old-growth forest to the Chinese fir plantation or the secondary forest. Our results show the shortages of soil nutrients from transforming old-growth forests into plantations or secondary forests and indicate the urgent need to preserve the remaining old-growth forests and increase stand ages by reducing forest disturbances. Therefore, determining the optimal stand type and slope location can effectively promote the accumulation of carbon, nitrogen, and phosphorus nutrients in the topsoil, which is essential for improving the planning and implementation of appropriate forest restoration and ecosystem management strategies.

This study investigated the effects of ultrasound on the self-assembly behavior of pea protein (PP)-high methoxyl pectin (HMP) complexes at pH 2.0 through transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and intrinsic fluorescence analysis. The emulsion stabilization mechanism of PP-HMP treated with ultrasound (PP-HMP-US) was also elucidated. The results indicated that ultrasound increased the emulsifying activity index (EAI) and emulsifying stability index (ESI) of PP-HMP. Moreover, PP-HMP-US-based emulsions formed small, dispersed oil drops, which were stable during storage. PP-HMP- and PP-HMP-US-based emulsions did not demonstrate any creaming. The TEM results revealed that ultrasound can regulate the self-assembly behavior of PP and HMP to form spherical particles with a core–shell structure. This structure possessed low turbidity, a small particle size, and high absolute zeta potential values. The FTIR and intrinsic fluorescence spectra demonstrated that ultrasound increased the α-helix and β-sheet contents and exposed the tryptophan groups to more hydrophilic environments. Ultrasound also promoted the PP-HMP self-assembly through electrostatic interaction and improved its oil–water interfacial behavior, as indicated by the EAI and ESI values of PP-HMP-US-based emulsions. The current results provide a reference for the development of an innovative emulsifier prepared by ultrasound-treated protein–pectin complexes at low pH.

wetA, one of the conidiation center regulatory genes in many filamentous fungi, plays an important role in promoting asexual spores (conidia) maturation. Our recent research has found that knocking out or overexpressing MrwetA (a homolog of wetA) in Monascus ruber M7 does not affect the development of its asexual spores like other fungi, but both repress the development of its sexual spores (ascospores). However, the mechanism remains unclear. In this study, the function of MrwetA on sexual reproduction and secondary metabolism in M. ruber M7 was confirmed by a complementary experiment. Moreover, the regulatory roles of MrwetA in modulating the expression of genes involved in sexual reproduction, meiosis, and biosynthesis of Monascus pigment and citrinin were analyzed based on the transcriptional data. These results not only contribute to clarifying the regulation of the reproduction and secondary metabolism of Monascus spp., but also to enriching the regulation molecular mechanism of reproduction in filamentous fungi.

Monascus pigments (MPs), a class of secondary metabolites produced by Monascus spp., can be classified into yellow, orange, and red MPs according to their differences in the wavelength of the maximum absorption. However, the biosynthetic sequence and cellular biosynthesis mechanism of different MPs components are still not yet completely clear in Monascus spp. In this study, the subcellular localization of five MPs synthases was investigated using fluorescent protein fusion expression. The results revealed that the proteins encoded by the MPs biosynthetic gene cluster were compartmentalized in various subcellular locations, including the mitochondrial polyketide synthase MrPigA, cytosolic enzymes consisting of the ketoreductase MrPigC, the oxidoreductase MrPigE, and the monooxygenase MrPigN, and the cell-wall-bound oxidoreductase MrPigF. Moreover, the correct localization of MrPigF to the cell wall was crucial for the synthesis of orange MPs. Lastly, we discussed the compartmentalized biosynthetic pathway of MPs. This study will not only be helpful in clarifying the biosynthetic sequence and biosynthesis mechanism of different MPs but also provides new insights into the cellular biosynthesis of secondary metabolites in filamentous fungi.

The mechanisms underlying latitudinal and longitudinal patterns in species diversity remain a central issue in ecology and are vital for effective biodiversity conservation. Few studies have been conducted to synthesize the latitudinal patterns and the underlying mechanisms of multi-dimensional biodiversity in Chinese Nature Reserves, and we will provide comprehensive patterns of species and phylogenetic diversity for plant species along the latitudinal patterns. In this study, we selected 10,458 angiosperm species from 157 China’s nature reserves along the latitudinal gradients to explore the geographical distribution patterns of species richness (SR), phylogenetic diversity (PD), phylogenetic endemism (PE), net relatedness index (NRI) and phylogenetic structure. The results indicated that the angiosperm’s SR, PD, PE and NRI increased along the latitudinal gradients in China. Species diversity was significantly correlated with phylogenetic diversity and phylogenetic endemism. Our findings suggested that the species in the higher latitude regions were significantly phylogenetically clustered, whereas the species in the lower latitude regions indicated phylogenetic overdispersion. Temperature strongly correlated with species diversity, phylogenetic diversity, phylogenetic endemism, and phylogenetic structure for all plants. Our results showed that the determinants of diversity patterns and phylogenetic structure were different among herbs and woody plants. For herbs, the reserve area had the highest explanatory power for phylogenetic endemism. For woody plants, temperatures determine their diversity patterns and phylogenetic structure. This study improves our understanding of the latitudinal and longitudinal gradients of species diversity, and phylogenetic structure and provides support for the improvement of biodiversity conservation in China.

The effect of pH on the occurrence states of peanut protein isolate (PPI) and high methoxyl pectin (HMP), and droplet breakup model of the emulsions under ultrasound were studied. Particle size distribution and scanning electron microscopy results showed that PPI-HMP existed a soluble complex at pH 5.0, had no interaction at pH 7.0, and was co-soluble at pH 9.0. Droplet breakup model results revealed that the characteristics of emulsion stabilised by PPI-HMP treated at pH 5.0 was different from that at pH 7.0 and 9.0. The average diameter of the droplet well satisfied the model. According to rheological properties, interface tension, and microstructure, the formation mechanism and characteristics of emulsion stabilised by PPI-HMP treated at pH 5.0 was different from that at pH 7.0 and pH 9.0. The research provided a reference for constructing emulsions using pH-shifted PPI-HMP under ultrasound.

We investigated the impact of seasons of the year on microbiota and physicochemical indices in industrial-scale fermentation of Sichuan Baoning vinegar. Illumina HiSeq sequencing results showed significant differences (P 0.05), the increase in total acidity was highest in the autumn. Acetic acid content in raw vinegar was highest in the autumn (3472.42 mg/100 mL), and lowest in the summer (2304.01 mg/100 mL). This study provides a theoretical basis for the production of Sichuan bran vinegar with consistent quality and provides insights into the quality control of traditional fermented foods.

Species are changing their elevational distributions in response to climate change, leading to biodiversity loss and changes in community structure. Yet whether native and non-native species have consistent elevational shifts remains to be evaluated. Subtropical mountains are rich in biodiversity, sensitive to climate change, and are experiencing high risks of biological invasion. Hence exploring the changes in species elevational distributions induced by climate change in subtropical mountains is an urgent need. Here, we explored the impact of climate change on the elevational distribution of seed plant species in Jinfo Mountain (Mt. Jinfo), a subtropical mountain in China with rich plant diversity. Notably, we compared the elevational redistributions of native and non-native plants in response to climate change. The results showed that the elevational centroids of native plant species moved downhill, while those of non-native plants shifted upward on average. The upper limit of native plants shifted downward, while the upper limit of non-native plants shifted upward on average. The elevational shifts of non-native plants were dominated by changes in the upper range limits, while those of native plants were affected by the lower limits. These opposite elevational shifts of native vs non-native species led to the increase in the elevational range size of the non-native plants, but decrease in the elevational range size of native plants, especially in high altitudes. The differences in the directions and magnitudes of elevational shifts between the native and non-native plants are mainly due to differences in their climate adaptation. Changes in temperature and precipitation influenced the elevational range shifts of native plants but not of non-native ones. This study provides a new perspective for understanding the elevational redistribution of native and non-native plant species in subtropical mountains, and suggests that climate change has stronger influence on native than non-native species.

Oil body emulsions (OBEs) affect the final oil yield as an intermediate in the concurrent peanut oil and protein extraction process using an aqueous enzyme extraction (AEE) method. Roasting temperature promotes peanut cell structure breakdown, affecting OBE composition and stability and improving peanut oil and protein extraction rates. Therefore, this study aimed to investigate the effects of pretreatment at different roasting temperatures on peanut oil and protein yield extracted through AEE. The results showed that peanut oil and protein extraction rates peaked at 90 °C, 92.21%, and 77.02%, respectively. The roasting temperature did not change OBE composition but affected its stability. The OBE average particle size increased significantly with increasing temperature, while at 90 °C, the zeta potential peaked, and the interfacial protein concentration hit its lowest, indicating OBE stability was the lowest. Optical microscopy and confocal laser scanning microscopy confirmed the average particle size findings. The oil quality obtained after roasting treatment at 90 °C did not differ significantly from that at 50 °C. The protein composition remained unaffected by the roasting temperature. Conclusively, the 90 °C roasting treatment effectively improved the yield of peanut oil extracted using AEE, providing a theoretical basis for choosing a suitable pretreatment roasting temperature.

In this study, the internal relationships among oil bodies (OBs), the protein–phospholipid interactions in aqueous phase, oil–water interface behavior, and the stability of reconstituted OBs were analyzed from the bulk phase, interface, and macro perspectives, and the stability mechanism of OBs was discussed. OB proteins and phospholipids were combined through hydrophobic and electrostatic interactions, resulting in the stretching of protein conformation. OB proteins and phospholipids act synergistically to increase interface pressure and the rate of increase in interface pressure with relatively stable elastic behavior, which is beneficial to the formation and stability of interfacial films. When OBs were reconstituted by an OB protein–phospholipid complex system, phospholipids bound to OB proteins through hydrophobic and electrostatic interactions. OB proteins and phospholipids uniformly covered the oil droplet surface of reconstituted OBs to form a stable interfacial film, which maintained the stability of OBs. The addition of phospholipids significantly reduced the particle size of OBs prepared by OB proteins in a dose-dependent manner, and particle size decreased with the increase in phospholipid content (p < 0.05). Phospholipids increased the net surface charge, enhanced electrostatic repulsion, and improved the physicochemical stability of reconstituted OBs. The stability mechanism elucidated in this study provides a theoretical basis for the demulsification of peanut OBs.

Root nutrients are required for the growth and development of roots and shoots, which are closely related to soil quality and fruit productivity. In this study, trees of contrasting stand ages, including young, middle-aged, and old trees, were selected in field sites with common management practices in the navel orange (Citrus sinensis) orchards of Southern China. The fine root N decreased with soil depth and the fine root P was higher of old trees (1.82 g kg-1) than young (1.57 g.kg-1) and middle-aged trees (1.37 g. kg-1). Soil organic C, total N, and P generally increased with plant age in the rhizosphere and bulk soils, while reverse trend was found for sucrase and urease activities. Interestingly, acid phosphatase activity was much higher at a lower depth (202 and 82 g.kg-1 OC d-1 for rhizosphere and bulk soils, respectively) than at an upper depth (46 and 43 g.kg-1 OC d-1 for rhizosphere and bulk soils, respectively). In conclusion, root and soil nutrients generally increased with plant growth. Fine root N decreased while fine root P remained unchanged with soil depth due to the content and rhizosphere effect of index at different soil layers related to N and P, respectively.

Bitter peptides in the enzymatic hydrolysates were prepared and purified from wheat gluten using aqueous ethanol solutions and macroporous resin, which has opened a new road for the extraction and separation of bitter peptides. This report contains the release regularity of bitter peptides and the factors affecting the change of bitter intensity during enzymatic hydrolysis, providing a scientific basis for the research on debitterizing method. In this study, the effects of different degrees of hydrolysis (DH) and enzyme active sites on the bitter peptide content and bitter taste thresholds were discussed. The relationship between amino acid composition, molecular weight distribution, surface hydrophobicity and bitter taste thresholds was extensively researched. The results showed the exposure of hydrophobic amino acids and the bitterness intensity of the hydrolysates increased as the DH increased, and the bitterness of wheat gluten hydrolysates (WGHs) hydrolyzed by Alcalase was stronger than that of Trypsin. According to correlation analysis, the proportion of total hydrophobic amino acid is the first factor that affects the sensory properties of bitter peptide, and the release content of bitter peptides and the content of total bitter amino acids are the second, following by the content of peptide in the molecular weight range of 500–1,000 Da and the surface hydrophobicity. The amino acid sequence of bitter peptides from WGHs were identified and predicted using high performance liquid chromatography-mass spectrometry (HPLC-MS/MS) and bioinformatics. It was found that the molecular weight of most of the peptides was below 1,500 Da, and the Q value was higher than 5.86 kJ/mol.

Acetic acid bacteria (AAB) are Gram-negative obligate aerobics in Acetobacteraceae family. Producing acetic acid and brewing vinegars are one of the most important industrial applications of AAB, attributed to their outstanding ability to tolerate the corresponding stresses. Several unique acid resistance (AR) mechanisms in AAB have been revealed previously. However, their overall AR strategies are still less-comprehensively clarified. Consequently, omics analysis was widely performed for a better understanding of this field. Among them, transcriptome has recently obtained more and more attention. However, most currently reported transcriptomic studies were conducted under lab conditions and even in low-acidity environment, which may be unable to completely reflect the conditions that AAB confront under industrialized vinegar-brewing processes. In this study, we performed an RNA-Seq transcriptomic analysis concerning AAB’s AR mechanisms during a continuous and periodical industrial submerged vinegar fermentation process, where a single AAB strain performed the fermentation and the acetic acid concentration fluctuated between ~8% and ~12%, the highest acidity as far we know for transcriptomic studies. Samples were directly taken from the initial (CK), mid, and final stages of the same period of the on-going fermentation. 16S rRNA sequence analysis indicated the participation of Komagataeibacter europaeus in the fermentation. Transcriptomic results demonstrated that more genes were downregulated than upregulated at both mid and final stages. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrich analysis reflected that the upregulated genes mainly carried out tricarboxylic acid cycle and oxidative phosphorylation processes, probably implying a considerable role of acetic acid overoxidation in AR during fermentation. Besides, upregulation of riboflavin biosynthesis pathway and two NAD+-dependent succinate-semialdehyde dehydrogenase-coding genes suggested a critical role of succinate oxidation in AR. Meanwhile, downregulated genes were mainly ribosomal protein-coding ones, reflecting that the adverse impact on ribosomes initiates at the transcription level. However, it is ambiguous whether the downregulation is good for stress responding or it actually reflects the stress. Furthermore, we also assumed that the fermentation stages may have a greater effect on gene expression than acidity. Additionally, it is possible that some physiological alterations would affect the AR to a larger extent than changes in gene expression, which suggests the combination of molecular biology and physiology research will provide deeper insight into the AR mechanisms in AAB.

The microbial community plays an important role on the solid-state fermentation (SSF) of Chinese cereal vinegar, where acetic acid bacteria (AAB) and lactic acid bacteria (LAB) are the dominant bacteria. In this study, the top-down (in situ) and bottom-up (in vitro) approaches were employed to reveal the interaction of AAB and LAB in SSF of Shanxi aged vinegar (SAV). The results of high-throughput sequencing indicates that Acetobacter pasteurianus and Lactobacillus helveticus are the predominant species of AAB and LAB, respectively, and they showed negative interrelationship during the fermentation. A. pasteurianus CGMCC 3089 and L. helveticus CGMCC 12062, both of which were isolated from fermentation of SAV, showed no nutritional competition when they were co-cultured in vitro. However, the growth and metabolism of L. helveticus CGMCC 12062 were inhibited during SSF due to the presence of A. pasteurianus CGMCC 3089, indicating an amensalism phenomenon between these two species. The transcriptomic results shows that there are 831 differentially expressed genes (|log2 (Fold Change)| > 1 and, p ≤ 0.05) in L. helveticus CGMCC 12062 under co-culture condition comparing to its mono-culture, which are mainly classified into Gene Ontology classification of molecular function, biological process, and cell composition. Of those 831 differentially expressed genes, 202 genes are up-regulated and 629 genes are down-regulated. The down-regulated genes were enriched in KEGG pathways of sugar, amino acid, purine, and pyrimidine metabolism. The transcriptomic results for A. pasteurianus CGMCC 3089 under co-culture condition reveals 529 differentially expressed genes with 393 up-regulated and 136 down-regulated, and the genes within KEGG pathways of sugar, amino acid, purine, and pyrimidine metabolism are up-regulated. Results indicate an amensalism relationship in co-culture of A. pasteurianus and L. helveticus. Therefore, this work gives a whole insight on the interaction between the predominant species in SSF of cereal vinegar from nutrient utilization, endogenous factors inhibition and the regulation of gene transcription.

γ-aminobutyric acid (GABA) is an important inhibitory neurotransmitter in the human body, but its content decreases with age. So it is suitable to supplement the body's GABA from diet. Hongqu wine is popular because of the addition of Monascus strains in the saccharification process, which makes the wine rich in functional ingredients such as GABA, and monacolin K. In this study, the fermentation parameters of Hongqu wine were optimised to maximise the GABA content through response surface methodology (RSM). The optimal conditions were as follows: 500 g of steamed rice was mixed with 115.4% of boiled water containing 10 g of sodium glutamate and adjusted to pH 3.8 with lactic acid, and then 32% of Hongqu seed inoculum was added. After 5 days of fermentation at 28 °C, 1.5 g of activated yeast was inoculated for ethanol fermentation at 30 °C for 5 days. Finally, the average content of GABA in Hongqu wine amounted to 710.24 mg L-1, which is close to the value predicted by RSM model (692.44 mg L-1), indicating the statistical fit is good. This provided technical support and theoretical guidance for the production of Hongqu wine rich in GABA by two-stage fermentation.

The aqueous enzymatic method is a form of green oil extraction technology with limited industrial application, owing to the need for the demulsification of the oil body intermediate product. Existing demulsification methods have problems, including low demulsification rates and high costs, such that new methods are needed. The free fatty acids produced by lipid hydrolysis can affect the stability of peanut oil body (POB) at a certain concentration. After screening even-carbon fatty acids with carbon chain lengths below ten, caproic acid was selected for the demulsification of POB using response surface methodology and a Box–Behnken design. Under the optimal conditions (caproic acid concentration, 0.22%; solid-to-liquid ratio, 1:4.7 (w/v); time, 61 min; and temperature, 79 °C), a demulsification rate of 97.87% was achieved. Caproic acid not only adjusted the reaction system pH to cause the aggregation of the POB interfacial proteins, but also decreased the interfacial tension and viscoelasticity of the interfacial film with an increasing caproic acid concentration to realize POB demulsification. Compared to pressed oil and soxhlet-extracted oil, the acid value and peroxide value of the caproic acid demulsified oil were increased, while the unsaturated fatty acid content and oxidation induction time were decreased. However, the tocopherol and tocotrienol contents were higher than those of the soxhlet-extracted oil. This study provides a new method for the demulsification of POB.

Coconut water (CW) is a popular and healthful beverage, and ensuring its quality is crucial for consumer satisfaction. This study aimed to explore the potential of near-infrared spectroscopy (NIRS) and chemometric methods for analyzing CW quality and distinguishing samples based on postharvest storage time, cultivar, and maturity. CW from nuts of Wenye No. 2 and Wenye No. 4 cultivars in China, with varying postharvest storage time and maturities, were subjected to NIRS analysis. Partial least squares regression (PLSR) models were developed to predict reducing sugar and soluble sugar contents, revealing moderate applicability but lacking accuracy, with the residual prediction deviation (RPD) values ranging from 1.54 to 1.83. Models for TSS, pH, and TSS/pH exhibited poor performance with RPD values below 1.4, indicating limited predictability. However, the study achieved a total correct classification rate exceeding 95% through orthogonal partial least squares discriminant analysis (OPLS-DA) models, effectively discriminating CW samples based on postharvest storage time, cultivar, and maturity. These findings highlight the potential of NIRS combined with appropriate chemometric methods as a valuable tool for analyzing CW quality and efficiently distinguishing samples. NIRS and chemometric techniques enhance quality control in coconut water, ensuring consumer satisfaction and product integrity.

Monascus spp. are traditional medicinal and edible filamentous fungi in China, and can produce various secondary metabolites, such as Monascus pigments (MPs) and citrinin (CIT). Genetic modification methods, such as gene knock-out, complementation, and overexpression, have been used extensively to investigate the function of related genes in Monascus spp.. However, the resistance selection genes that can have been used for genetic modification in Monascus spp. are limited, and the gene replacement frequency (GRF) is usually

The biosynthesis of penicillin G (PG) is compartmentalized, and the transportation of the end and intermediate products, and substrates (precursors) such as L-cysteine (L-Cys), L-valine (L-Val) and phenylacetic acid (PAA) requires traversing membrane barriers. However, the transportation system of PAA as a side chain of PG are unclear yet. To discover ABC transporters (ABCTs) involved in the transportation of PAA, the expression levels of 38 ABCT genes in the genome of Monascus ruber M7, culturing with and without PAA, were examined, and found that one abct gene, namely abct31, was considerably up-regulated with PAA, indicating that abct31 may be relative with PAA transportation. Furthermore the disruption of abct31 was carried out, and the effects of two PG substrate's amino acids (L-Cys and L-Val), PAA and some other weak acids on the morphologies and production of secondary metabolites (SMs) of Δabct31 and M. ruber M7, were performed through feeding experiments. The results revealed that L-Cys, L-Val and PAA substantially impacted the morphologies and SMs production of Δabct31 and M. ruber M7. The UPLC-MS/MS analysis findings demonstrated that Δabct31 did not interrupt the synthesis of PG in M. ruber M7. According to the results, it suggests that abct31 is involved in the resistance and detoxification of the weak acids, including the PAA in M. ruber M7.

Vinegar is an acid condiment shared all over the world. According to the raw materials, vinegar can be mainly divided into fruit and cereal ones, both of which possess unique aroma and flavor characteristics and corresponding volatile organic compounds (VOCs). Many studies about vinegar VOCs' (VVOCs) sorts, analytical methods, and forming mechanisms have been done. In this review, the main categories of vinegar and their distribution in the world are briefly introduced, then VVOCs' analytical and identified methods, types, and forming processes are summarized. Additionally, the VVOCs' research directions are discussed and prospected. According to the searched literatures, this study is the first to systematically review the analytical methods, sorts, and formation mechanisms of VVOCs, which will make the readers better understand the vinegar's aromas and flavors and their producing mechanisms.

The changes in physicochemical properties of salt-soluble proteins and gel prepared with chicken breast muscles during −1.5oC (ice-temperature) and 4oC (refrigerated temperature) storage were investigated. Compared with the samples of 4oC stored group, the decrease in solubility, the content of total sulfhydryl and available sulfhydryl groups of SSP from chicken breast muscles at −1.5oC storage was effectively delayed, and the increase of both surface hydrophobicity and content of disulfide bond was obviously inhibited. The gel prepared with −1.5oC stored samples had much higher holding capacity of water, lower cooking loss, better springiness, and more uniform three-dimensional network structures with smaller-sized pores than those from 4°C stored-samples. Additionally, great changes in the proportions of non-flowing water and free water ratio were observed during 4oC storage. In short, the ice-temperature storage used for chicken meat preservation was better than refrigerated storage.

Effects of inulin with short and long-chain on pasting, texture and rheological properties of sweet potato starch (SPS) were investigated. Subsequently, the interaction mechanism between inulin and SPS was discussed. Both short and long-chain inulin could decrease all the viscosity parameters and raise the pasting temperature (GT) of SPS-inulin mixes. With the increase of inulin addition, the hardness and gumminess of SPS gel decreased, while tan δ and temperature of G’ Max rose. Inulin could inhibit SPS granule swelling, and made SPS granules concentrate in the smaller ones. Inulin also remarkably lowered the content of leached amylose (p

Acetic acid bacteria (AAB) are a group of Gram-negative, strictly aerobic bacteria, including 19 reported genera until 2021, which are widely found on the surface of flowers and fruits, or in traditionally fermented products. Many AAB strains have the great abilities to incompletely oxidize a large variety of carbohydrates, alcohols and related compounds to the corresponding products mainly including acetic acid, gluconic acid, gulonic acid, galactonic acid, sorbose, dihydroxyacetone and miglitol via the membrane-binding dehydrogenases, which is termed as AAB oxidative fermentation (AOF). Up to now, at least 86 AOF products have been reported in the literatures, but no any monograph or review of them has been published. In this review, at first, we briefly introduce the classification progress of AAB due to the rapid changes of AAB classification in recent years, then systematically describe the enzymes involved in AOF and classify the AOF products. Finally, we summarize the application of molecular biology technologies in AOF researches.

To regulate the degradation of transgenic DNA and lay theoretical foundations for the rational utilization of genetically modified (GM) products, variations in copy numbers and structural characteristics of DNA from GM soybean event GTS 40-3-2 during soybean protein concentrate (SPC) preparation were evaluated. Results showed that defatting and the first ethanol extraction were key procedures inducing DNA degradation. After these two procedures, copy numbers of the lectin and cp4 epsps targets decreased by more than 4 × 108, occupying 36.88–49.30% of the total copy numbers from raw soybean. Atomic force microscopy images visually revealed the degradation of DNA that thinned and shortened during SPC preparation. Circular dichroism spectra suggested a lower helicity of DNA from defatted soybean kernel flour and a conformation transition of DNA from B-type to A-type after ethanol extraction. The fluorescence intensity of DNA decreased during SPC preparation, verifying the DNA damage along this preparation chain.

Soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) are the core components that mediate vesicle fusion, and they play an important role in secondary metabolism of filamentous fungi. However, in Monascus spp., one of the traditional medicinal and edible filamentous fungi, the members and function of SNAREs remain unknown. Here, twenty SNAREs in M. ruber M7 were systematically identified based on the gene structure, amino acid structure and phylogenetic analysis and were classified into four subfamilies. We also compared the expression profiles of twenty MrSNAREs in M. ruber M7 and its deletion mutants, ΔmrpigA and ΔpksCT, which could not produce Monascus pigment and citrinin, respectively. The results indicated that these MrSNAREs showed distinct expression patterns in the three strains. Compared to M. ruber M7, the expression levels of Mrtlg2, Mrbet1, Mrgos1 and Mrsec22 remained higher in ΔmrpigA but lower in ΔpksCT, which could be reason to consider them as potential candidate genes involved in secondary metabolism for further functional characterization. Further, the significant upregulation of Mrpep12 and Mrvtil in ΔpksCT is worthy of attention for further research. Our results provide systematic identification and expression profiling of the SNARE family in Monascus and imply that the functions of MrSNAREs are specific to different secondary metabolic processes.

Peanut protein isolate was hydrolyzed by trypsin. The resulting peanut peptide fractions (PPF) were then divided into three molecular weight components by ultrafiltration (PPF1, MW >5 kDa; PPF2, 3 kDa < MW

Edible bilayer films prepared using an additional of zein (Z) layer casted on the corn-wheat (CW) starch films were prepared and characterized in terms of colour, thickness, water content, optical, water vapour permeability (WVP), mechanical properties and antioxidative capacity. Results showed that the colour, thickness, water content, elongation at break (E), and antioxidative capacity increased with the increasing of zein addition, but WVP and tensile strength (TS) decreased. In comparison with biaxially oriented polypropylene polyethylene composite films (BOPP-PE), CW10/Z3 and CW8/Z3 even showed better antioxidative capacity and elongation at break (E). The surface and cross-section micrographs were imaged by scanning electron microscopy (SEM) and atomic force microscopy (AFM). On both of SEM and AFM images, CW10/Z1 and CW10/Z2 films exhibited smoother surface and more compacted structure than other films. Besides, CW10/Z3 and CW8/Z3 of SEM images showed the better cross-section. Therefore, CW/Z edible bilayer films could be potentially used as a new inner package material for oil bag in instant food to improve the development of food industry. Keywords: Bilayer films, Corn-wheat starch, Zein, Antioxidative capacity, Surface and cross-sectional morphology

Hostplant limitation is a key focus of the spatial interaction between a phytophagous butterfly and a hostplant. The possible drivers related to the hostplants are species richness, abundance, or availability, but no consensus has been reached. In this study, we investigated the butterfly–hostplant interaction using the case of the forest canopy butterfly T. aureus in Asia, whose narrow distribution is assumed to be limited by its exclusive hostplant, Magnoliaceae, in tropic and subtropic regions. We recorded the Magnoliaceae species, as well as plant and butterfly individuals in transect, and we collected tree traits and topography variables. The results confirm that this butterfly is limited by the hostplants of their larval stage. The hostplants occurred exclusively in the middle-mountain region, with preference only for primeval forests. The hostplant resource was superior in the middle-mountain region, particularly concentrating in primeval forests. The hostplant’s abundance, together with altitude and habitat types, was critical to this butterfly’s occurrence, while those hostplant trees with an exposed crown, which are demanded by this butterfly in its oviposition, were the best drivers of positive butterfly–hostplant interactions. Therefore, the hostplant’s limitation was mainly determined by the availability of the hostplant. This case study supports the hypothesis that the limitation on this butterfly’s occurrence was driven by the hostplant’s availability, and it suggests that protecting high-quality forests is a valuable activity and essential in the conservation of canopy butterflies.

The present study aimed to characterize melanin pigment extracted from Gluconobacter oxydans FBFS 97. After 14 days of culture at 28 °C in GY (glucose and yeast extract) liquid-state medium, G. oxydans FBFS97 produce the maximum melanin, up to about 12–15 mg/L. The physicochemical characteristics of the extracted melanin showed an ability to dissolve in 1 mol/L NaOH or 1 mol/L KOH, and insolubility in water and most organic solvents, such as chloroform and petroleum ether. The extracted melanin was confirmed to be exact melanin by ultraviolet-visible spectrophotometry, Fourier-transform infrared spectroscopy, thin-layer chromatography, elemental analysis, and scanning electron microscopy. The UV-visible spectrum of G. oxydans FBFS97 exhibited a maximum absorption peak at 230 nm. Extracted melanin demonstrated significant free radical-scavenging activity by DPPH and ABTS methods. The IC50 value of the extracted melanin for scavenging 50% DPPH radicals was 36.94 μg/mL, and the IC50 value of antioxidant activity for ABTS was 4.06 μg/mL. Hence, G. oxydans FBFS97 has the potential to be a new candidate for melanin production.

The detailed investigation of food-grade emulsions, which possess considerable structural and functional advantages, remains ongoing to enhance our understanding of these dispersion systems and to expand their application scope. This work reviews the applications of food-grade emulsions on the dispersed phase, interface structure, and macroscopic scales; further, it discusses the corresponding factors of influence, the selection and design of food dispersion systems, and the expansion of their application scope. Specifically, applications on the dispersed-phase scale mainly include delivery by soft matter carriers and auxiliary extraction/separation, while applications on the scale of the interface structure involve biphasic systems for enzymatic catalysis and systems that can influence substance digestion/absorption, washing, and disinfection. Future research on these scales should therefore focus on surface-active substances, real interface structure compositions, and the design of interface layers with antioxidant properties. By contrast, applications on the macroscopic scale mainly include the design of soft materials for structured food, in addition to various material applications and other emerging uses. In this case, future research should focus on the interactions between emulsion systems and food ingredients, the effects of food process engineering, safety, nutrition, and metabolism. Considering the ongoing research in this field, we believe that this review will be useful for researchers aiming to explore the applications of food-grade emulsions.

Monascus-type azaphilone pigments (MonAzPs) are produced in multi-thousand ton quantities each year and used as food colorants and nutraceuticals in East Asia. Several groups, including ours, described MonAzPs biosynthesis as a highly complex pathway with many branch points, affording more than 110 MonAzP congeners in a small group of fungi in the Eurotiales order. MonAzPs biosynthetic gene clusters (BGCs) are also very complex and mosaic-like, with some genes involved in more than one pathway, while other genes playing no apparent role in MonAzPs production. Due to this complexity, MonAzPs BGCs have been delimited differently in various fungi. Since most of these predictions rely primarily on bioinformatic analyses, it is possible that genes immediately outside the currently predicted BGC borders are also involved, especially those whose function cannot be predicted from sequence similarities alone. Conversely, some peripheral genes presumed to be part of the BGC may in fact lay outside the boundaries. This study uses a combination of computational and transcriptional analyses to predict the extent of the MonAzPs BGC in Monascus ruber M7. Gene knockouts and analysis of MonAzPs production of the mutants are then used to validate the prediction, revealing that the BGC consists of 16 genes, extending from mrpigA to mrpigP. We further predict that two strains of Talaromyces marneffei, ATCC 18224 and PM1, encode an orthologous but non-syntenic MonAzPs BGC with 14 genes. This work highlights the need to use comprehensive, integrated approaches for the more precise determination of secondary metabolite BGC boundaries.

Cocultivation is an emerging and potential way to investigate microbial interaction in the laboratory. Extensive researches has been carried out over the years, but some microorganism cocultivation are not easy to implement in the laboratory, especially the fungus-fungus (FF) cocultivation, owing to the obstacles such as fungal different growth rate, limited growing space, hyphae intertwining, and difficulty of sample separation, etc. In this research, a double-sided petri dish (DSPD) was designed and carried out as a tool to study FF cocultivation in the laboratory. A natural FF cocultivation of Monascus spp. and Aspergillus niger inspired from black-skin-red-koji (BSRK), were studied. By using DSPD, the aforementioned obstacles in the FF cocultivation study were overcome through co-culturing Monascus spp. and A. niger on each side of DSPD. The characteristics of monocultured and co-cultured Monascus spp. and A. niger were compared and analyzed, including colonial and microscopic morphologies, and main secondary metabolites (SMs) of Monascus spp. analyzed by high performance liquid chromatography. And a novel SM was found to be produced by Monascus ruber M7 when co-cultured with A. niger CBS 513.88. Since the above mentioned obstacles, were overcome, we obtained good quality of transcriptome data for further analysis. These results indicate that DSPD might be an efficient tool for investigation of microbial interaction, in particular, for FF interaction.

To lay a theoretical basis for the preparation of peanut protein-based adhesives and promote the sustainable development of the adhesive industry, properties of peanut protein isolate (PPI), arachin and conarachin-based adhesives modified by urea and epichlorohydrin (ECH) were investigated under different urea concentrations. When the urea concentration was 2 mol l−1, the wet shear strength of the PPI-based adhesive was 1.24 MPa with the best water resistance. With the increase of urea concentration from 0 to 4 mol l−1, the apparent viscosity of the PPI-based adhesive increased from 3.87 to 136.80 Pa s and the solid content increased from 18.11% to 31.11%. Compared with conarachin-based adhesive, the properties of arachin-based adhesive were improved more obviously during the combined modification. Scanning electron microscopy images illustrated that when the urea concentration was 2 mol l−1, the surface of the PPI-based adhesive was more compact and smoother, which was beneficial to the improvement of water resistance and related to the structure changes of arachin and conarachin components. Fourier-transform infrared spectroscopy results indicated that different urea concentrations caused the change of ester and ether bonds in the PPI-based adhesive, which was mainly related to arachin component. Thermogravimetry results suggested that when the urea concentration was 2 mol l−1, the decomposition temperature of protein skeleton in the PPI-based adhesive reached a maximum of 314°C exhibiting the highest thermal stability. The improvement of the thermal stability of conarachin was greater than that of arachin during the combined modification.

Peanut oil body (POB), which is rich in unsaturated fatty acids and bioactive substances, is widely used in cosmetics, food, and medicine. Compared with synthetic emulsifiers, peanut oil bodies have health advantages as natural emulsions. The physicochemical properties of oil bodies affect their food processing applications. To improve peanut oil body yield, cell-wall-breaking enzymes were screened for aqueous enzymatic extraction. The optimum conditions were as follows: enzymatic hydrolysis time, 2 h; material-to-liquid ratio, 1 : 5 (m/v); enzyme concentration, 2% (v/m); and temperature, 50°C. Oil body stability was closely related to pH. With increasing pH, the average particle size and zeta-potential of the oil bodies increased, indicating aggregation, as confirmed by microstructure analysis. At pH 11, exogenous proteins at the oil body interface were eluted, leaving endogenous proteins, which led to a decreased interfacial protein content and oil body aggregation. Therefore, oil body stability decreased under alkaline pH conditions, but no demulsification occurred.

To evaluate DNA fragmentation and GMO quantification during soya bean protein concentrate and isolate preparation, genetically modified soya bean event GTS 40-3-2 (Roundup ReadyTM soya bean, RRS) was blended with conventional soya beans at mass percentages of 0.9%, 2%, 3%, 5% and 10%. Qualitative PCR and real-time PCR were used to monitor the taxon-specific lectin and exogenous cp4 epsps target levels in all of the main products and by-products, which has practical significance for RRS labelling threshold and traceability. Along the preparation chain, the majority of DNA was distributed in main products, and the DNA degradation was noticed. From a holistic perspective, the lectin target degraded more than cp4 epsps target during both of the two soya bean proteins preparations. Therefore, the transgenic contents in the final protein products were higher than the actual mass percentages of RRS in raw materials. Our results are beneficial to the improvement of GMO labelling legislation and the protection of consumer rights.

It is well known that many organisms can perceive the magnetic field (MF), including the geomagnetic field, but how to feel MF is unclear. Recently, a study has claimed that a biological compass, namely a complex of the magnetic receptor (MagR) and blue light (BL) receptor (cryptochrome), has been found in Homo sapiens, Drosophila melanogaster, and Danaus plexippus, which may bring some new ideas to explore the mechanism of biomagnetism. Monascus spp. are edible filamentous fungi that can produce abundant beneficial secondary metabolites and have been used to produce food colorants for nearly 2000 years in the world, especially in China, Japan, and Korea. In this work, we firstly treated M. ruber M7 by BL (500 lux,465–467 nm), MF (5, 10, 30 mT), and the combination of MF and BL (MF-BL), respectively. The results revealed that, compared with the control (CK, neither BL nor MF), the MF alone had no effect on the growth and morphological characteristics of M7, but BL made the colonial diameters only 66.7% of CK’s and inhibited the formation of cleistothecia. Under MF-BL, the colony diameters were still 66.7% of CK’s, but the colonial growth and cleistothecia production inhibited by BL were partially restored. Then, we have found that the magR gene widely exists in the genomes of animals, plants, and microorganisms, and we have also discovered a magR gene in the M7 genome, hereinafter referred to mr-magR. Finally, the full-length cDNA of mr-magR was successfully cloned and expressed in Escherichia coli BL21 (DE3), and the Mr-MagR protein was purified by a Ni+-NTA column and identified by Western blot. These results have laid a foundation for further investigation on the relationship between Mr-MagR and BL receptor(s) that might exist in M7. According to a literature search, it is the first time to report magR in filamentous fungi.

Eurotium cristatum as the dominant fungi species of Fuzhuan brick tea in China, can produce multitudinous secondary metabolites (SMs) with various bioactivities. Polyketides are a very important class of SMs found in E. cristatum and have gained extensive attention in recent years due to their remarkable diversity of structures and multiple functions. Therefore, it is necessary to explore the polyketides produced by E. cristatum at the genomic level to enhance its application value. In this paper, 12 polyketide synthase (PKS) genes were found in the whole genome of E. cristatum E1 isolated from Fuzhuan brick tea. In addition, the qRT-PCR results further demonstrated that these genes were expressed. Moreover, metabolic analysis demonstrated E. cristatum E1 can produce a variety of polyketides, including citreorosein, emodin, physcion, isoaspergin, dihydroauroglaucin, iso-dihydroauroglaucin, aspergin, flavoglaucin and auroglaucin. Furthermore, based on genomic analysis, the putative secondary metabolites clusters for emodin and flavoglaucin were proposed. The results reported here will lay a good basis for systematically mining SMs resources of E. cristatum and broadening its application fields.

Monascus pigments (MPs) have been used as food colorants for several centuries in Asian countries and are currently used around the world via Asian catering. The MPs biosynthetic pathway has been well-illustrated; however, the functions of a few genes including mrpigH in the MPs gene cluster of M. ruber M7 are still unclear. In the current study, mrpigH was disrupted in Δmrlig4ΔmrpyrG, a highly efficient gene modification system, using mrpyrG as a selection marker, and ΔmrpigHΔmrlig4ΔmrpyrG::mrpyrG and ΔmrpigHΔmrlig4ΔmrpyrG have been obtained. Subsequently, their morphologies, biomasses, MPs and citrinin (CIT) production were analyzed, respectively. These results have revealed that the deletion of mrpigH has significant effects on the morphology and growth of M. ruber M7. Moreover, compared with M. ruber M7, the yields of MPs and CIT were drastically increased and decreased in mrpigH mutants, respectively.

Abstract:: The aim of this study was to detect the size changes of reverse micelles after extraction of peanut protein and their forward extraction rates. Factors that affect the size of reverse micelles and the extraction of peanut protein were also investigated. The size of reverse micelles and the size changes were measured according to the theory of dynamic light scattering under different conditions such as different sodium bis (2-ethylhexyl) sulfosuccinate (AOT) concentrations, pH values, ion concentrations, and salt species. With the increase of AOT surfactant concentrations in a certain range, the size of empty and full reverse micelles increased and the forward extraction rate decreased. The effect of pH on empty reverse micelles was not significant. However, the effect of pH on the full reverse micelle size and forward extraction rate were significant. Its forward extraction rate increased to the maximum 39.6% at pH 7.5. The increase of the salt concentration of a buffer solution in a certain range decreased the size of empty and full reverse micelles and reduced the forward extraction rate of peanut protein. Ionic species had important effects on reverse micelles and peanut protein extraction. An increase in the amount of buffer solution enlarged the empty reverse micelle size in 0.03%‒0.11% (V/V). However, it did not translate to a larger reverse micelle size. The size of the empty reverse micelles containing K2SO4 reached 24.1 nm with a 0.19% (V/V) buffer solution added. The sizes of the full reverse micelles were larger than those of the empty reverse micelles after forward extraction. However, maximum sizes were achieved with the addition of a 0.03% (V/V) buffer solution. The amount of 0.03% (V/V) buffer solution added was appropriate for extracting peanut protein.Supported by National Natural Science Foundation of China (21176058, 31171790, 21376064, 31201293), and Innovation Scientists and Technicians Troop Construction Projects of Zhengzhou City (ISTTCPZZC). Keywords:: Reverse micelle, Size, Forward extraction, Peanut protein