Food stands as a pivotal environmental element that exerts a profound influence on the survival of animals. Faced with food shortages, animals need to develop morphological, physiological, and behavioral strategies to improve their survival adaptability. Animals undergoing fasting tend to mobilize the reserved substances in the body to meet the energy needs for metabolism. In the present investigation, we assessed the influence of prolonged fasting on various physiological parameters related to fat catabolism, carbohydrate metabolism, and protein catabolism in female Japanese quails (Coturnix japonica). The treatment of Japanese quails was divided into four stages: the pre-fasting stage, Phase I (fasting for 1 day), Phase II (fasting for 4 days), and Phase III (fasting for 6-11 days). Compared with the pre-fasting stage, the following indicators changed significantly during prolonged fasting. (1) Fat catabolism: In the liver, the level of lipid droplets and free fatty acids (FFA), the activity of triacylglycerol lipase (TGL), the activity and mRNA level of hydroxymethylglutaryl-CoA synthetase (HMGCS), and the level of β-hydroxybutyric acid (BHBA) in the serum increased significantly, while the activity and mRNA level of carnitine acyltransferase I (CPTI) and carnitine acyltransferase II (CPT-II) decreased significantly. (2) Carbohydrate metabolism: The activity and mRNA levels of the pyruvate carboxylase (PC) and phosphoenolpyruvate carboxykinase (PEPCK) genes, and that of the glucose-6-phosphatase (G6Pase) in the liver increased significantly, while the mRNA level of the hexokinase domain containing 1 (HKDC1) and pyruvate kinase (PK) genes in the liver decreased significantly. (3) Protein catabolism: free amino acid levels in the liver and pectoral muscle increased significantly, whereas the mRNA levels of the asparagine synthetase (ASNS) and glutamate dehydrogenase (GLUD) genes in the liver decreased significantly, while the mRNA level of the nuclear factor-kappa B (NF-kB1 and NF-kB2) in the pectoral muscle increased significantly. Additionally, glucocorticoid levels significantly rose in Phase III compared with Phases I and II. Therefore, for prolonged fasting female Japanese quails, the mobilization of fat, fat decomposition, and generation of ketone bodies increased significantly, and gluconeogenesis in the liver also increased significantly, while glycolysis decreased significantly; protein decomposition, particularly in pectoral muscle, increased significantly. These results indicate that enhanced fat catabolism, protein catabolism, and gluconeogenesis, along with reduced glycolysis, could play an important role in the tolerance of female Japanese quails to prolonged fasting. These mechanisms might be significant for the birds to establish a temporary balance to maintain homeostasis under conditions of restricted exogenous energy supply.

Plant growth promoting rhizobacteria (PGPR) have potential application value in reducing metal accumulation in medicinal plants. The objective of this study was to isolate, characterize and evaluate the effects of endophyte on the growth and metal resistance of Codonopsis pilosula under Cadmium ion (Cd2+) stress. Five endophytic strains were isolated from the root of C. pilosula. Serratia (CPSE11, CPSE12), Enterobacter (CPSE22), Bacillus subtilis (CPSE32), and Microbacterium (CPSE8). Serratia fonticola CPSE11 showed high tolerance to Cd2+. The adsorption of Cd2+ was consistent with the first-order kinetic model, and had a strong correlation with the Langmuir model. The maximum single-layer adsorption capacity (q^m) was 58.47 mg/g (R2 > 0.9). In hydroponic experiments, 107 cfu/mL CPSE11 could effectively alleviate the toxic effect of Cd2+ (0, 5, 10 and 15 mg/L) on C. pilosula. Genomic analysis showed that CPSE11 has genes involved in extracellular polysaccharide (EPS) synthesis, transcription, transport, and metal resistance. These include czcB, cusA/czcA, cusB, and cusC, and genes encoding copper (Cu), silver (Ag), cadmium (Cd), zinc (Zn), and cobalt (Co) efflux pumps. CPSE11 enhances the resistance of C. pilosula to Cd2+ stress by producing siderophores, IAA, ACC, fixing nitrogen and regulating the antioxidant system. CPSE11 alleviates the toxic effect of Cd2+ stress on C. pilosula through EPS fixation, RND-type efflux system and specific translocation of metal tolerance gene family. EPS depend on ABC transporter and Wzx/Wzy pathway to produce. The research will promote the sustainable development of medicinal plants and the application of PGPR in metal stress.

Hydrolysis is the rate-limiting step in the anaerobic digestion of lignocellulose. In the present study, pulp and paper mill sludge (PPMS), a lignocellulose-rich, high-volume waste, which is difficult to be treated by traditional anaerobic digestion, was inoculated with rumen microorganisms for VFAs production. The maximum extent of VFA accumulation was 3839 mg/L after 84 h in the rumen fluid-inoculated digester, versus 2338 mg/L after 96 h in the digester without rumen fluid addition. The amount was 1.64 times higher than that of digester leachate inoculum. During VFAs production, the hydrolysable of lignocellulose and extracellular polymers were promoted by inoculating rumen liquid. High-throughput sequencing results (16S rRNA genes) showed that there was a significant succession of dominant microbial community during in vitro fermentation of PPMS by rumen fluid. Fermentation by rumen fluid is a potentially effective technology to boost VFAs production from a lignocellulose-rich biomass.

Long-term anaerobic conditions in septic tanks exacerbate the release of hazardous gases, such as hydrogen sulfide (H2S), which degrades urban air quality. While traditional iron salt addition effectively inhibits H2S production, its large-scale application imposes economic burdens and challenges for low-carbon emission reduction. To address this issue, this study proposes the use of scrap iron filings (SIFs) as a source of Fe2+ and Fe3+ ions and evaluates their efficacy in sulfide control through a long-term laboratory-scale septic tank reactor. Experimental results demonstrated that the addition of SIFs reduced the average concentration of dissolved sulfides by 45.6 % and gaseous H2S by 92.6 %. Microbial community analysis of septic tank sediments revealed a significant decrease in sulfate-reducing bacteria (SRB) and an increase in sulfur-oxidizing bacteria (SOB), indicating that SIFs influence microbial activity by suppressing sulfide generation while enhancing sulfide oxidation. Furthermore, the addition of SIFs slightly increased the carbon-to-nitrogen (C/N) and carbon-to-phosphorus (C/P) ratios in the effluent, potentially improving subsequent nitrogen and phosphorus removal in wastewater treatment. These findings suggest a promising strategy for reducing hydrogen sulfide emissions and corrosion in septic tanks.

Central venous catheter (CVC) related bacteremia is an essential cause of hospital infections associated with morbidity, mortality, and healthcare costs. Recent advancements in catheter coatings have demonstrated an effective strategy for preventing microbial colonization and biofilm formation. In this study, CVCs coated with green and facile laccase-manganese phosphate hybrid nanostructures [(Mn3(PO4)2·HNSs] prevented bacterial adhesion by 100%, 80%, 60%, and 58% for Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Escherichia coli, respectively. The modified CVCs inhibited planktonic bacterial growth by up to 95% under static and dynamic flow conditions. Furthermore, the prepared CVCs showed high hemocompatibility, appropriate mechanical properties, and long-term antibacterial performance, meeting the essential requirements of catheterization. The modified catheter offered superior detectability in magnetic resonance imaging (MRI) and computed tomography (CT) scans, a valuable advancement for ongoing patient monitoring. Moreover, in vivo assessment using the mouse catheterization model revealed no inflammatory response associated with the implanted CVCs. Therefore, the prepared laccase@ Mn3(PO4)2·HNSs could be a promising strategy for developing safe and effective antibacterial coatings to combat infections associated with biomedical devices.

Sweet sorghum (Sorghum bicolor Moench) seedling emergence and growth are significantly impeded by physical soil crusts (PSCs) in saline-alkaline soils. Abscisic acid (ABA) is a potent seed priming agent known for modulating plant physiological and metabolic responses under salinity stress. However, the influence of ABA priming on seedling emergence in PSCs remains unclear. This study conducted both pot and field experiment to examine the effects of ABA priming on enhancing seedling emergence under PSC conditions. ABA priming altered the balance of at least 24 endogenous phytohormones, including abscisic acid, jasmonic acid, gibberellins, ethylene, auxins, and cytokinins. Additionally, it reprogrammed starch and sucrose metabolism, resulting in the differential expression of genes encoding key enzymes such as AMY, BAM, and INV, which are crucial for converting complex sugars into readily available energy sources, thereby supporting seedling growth. Furthermore, 52 differentially expressed metabolites (DEMs) of flavonoids were identified in germinating seedlings, including 15 anthocyanins, 3 flavones, 7 flavonols, 6 isoflavones, 7 flavanones, and 14 other flavonoids. Genetic and metabolic co-expression network analysis, along with flavonoid biosynthesis pathway exploration, revealed that the biosynthesis of 17 key DEMs-including liquiritigenin, apigenin, kaempferide, syringetin, phloretin, formononetin, dihydrokaempferol, and xanthohumol-was regulated by 10 differentially expressed genes (DEGs) associated with flavonoid biosynthesis. These DEGs encoded 7 enzymes critical for this pathway, including chalcone synthase, shikimate O-hydroxycinnamoyltransferase, bifunctional dihydroflavonol 4-reductase, naringenin 7-O-methyltransferase, and anthocyanidin reductase. This regulation, along with reduced levels of superoxide anion (O2-) and malondialdehyde and increased antioxidant enzyme activities, suggested that flavonoids played a vital role in mitigating oxidative stress. These findings demonstrate that ABA priming can effectively enhance sweet sorghum seedling emergence in PSCs by accelerating emergence and boosting stress resistance.

Salt stress has become a major threat to peanut yield and quality, and salt stress is particularly detrimental to seedling growth. Combined analysis of the physiology and transcriptomics of salt-tolerant variety (NH5) and salt-sensitive variety (FH23) under 200 mM NaCl stress was conducted to identify the key factors influencing the differences in salt tolerance and to investigate the potential regulatory mechanisms and hub genes associated with salt tolerance in peanuts.

Malondialdehyde (MDA) content and electrolyte leakage rate were significantly increased under prolonged NaCl stress, with the increase in FH23 being even more pronounced. NH5 maintained intracellular osmotic homeostasis by accumulating free proline and soluble protein content. In addition, NH5 exhibited higher antioxidant enzyme activity. The net photosynthetic rate (Pn) of NH5 and FH23 decreased by 64.24% and 94.49% after 96 h of stress. The intercellular CO2 concentration (Ci) of NH5 significantly decreased by 7.82%, while that of FH23 increased by 42.74%. This suggests that non-stomatal limiting factors were the primary cause of the decline in photosynthesis observed in FH23. Transcriptome analysis revealed the presence of 12,612 differentially expressed genes (DEGs) in response to salt stress, with FH23 exhibiting a greater number than NH5. The number of upregulated genes was significantly higher than that of downregulated genes at 24 h of salt stress, whereas the number of downregulated genes exceeded that of upregulated genes at 48 h. Subsequently, Weighted Gene Co-expression Network Analysis (WGCNA) was performed in conjunction with physiological data. Twenty-four hub genes of salt response were identified, which encoded delta-1-pyrroline-5-carboxylate synthase, aldehyde dehydrogenase, SNF1-related protein kinase, magnesium transporter, temperature-induced lipocalin-1, and ERF transcription factors.

A regulatory network for potential salt tolerance in peanuts has been constructed. The findings revealed distinct mechanisms of response to salt tolerance and identified candidate genes for further investigation.

Brucellosis is a zoonosis that affects domestic and wild animals, causing reproductive disorders and significant economic losses in livestock. Brucella melitensis, B. abortus, and B. suis are the main agents of brucellosis in livestock and humans, thereby their control and eradication are crucial. Serological tests based on identification of antibodies against Brucella smooth lipopolysaccharides (sLPS) in the serum of infected animals are traditionally used. This approach shows two main limits: (i) tests can give false positives due to the similarity of Brucella sLPS with the LPS of other Gram-negative bacteria; (ii) antigen production represents a possible risk of zoonoses. In this work, a proteomic approach, starting from B. melitensis Brucellergene, was employed to identify possible Brucella antigenic proteins useful for a more specific and safe serological diagnosis. Four proteins binding to the infected swine serum were identified: (i) "probable sugar-binding periplasmic protein B. abortus str 2308A"; (ii) "peptide ABC transporter substrate-binding protein B. melitensis"; (iii) "GntR family transcriptional regulator B. melitensis"; (iv) "conserved hypothetical protein B. melitensis M28". These proteins could be promising specific antigens for serological investigations in swine. In the near future, these antigenic proteins could be synthesized in vitro and used to produce a safer and more specific diagnostic kit.

This study aimed to compare the structural and biological activities of neutral ginseng residue oligosaccharides (GRO-N) and neutral ginseng polysaccharides (GP-N). Their structures of GRO-N and GP-N were established based on their molecular weight (Mw), monosaccharide composition, Fourier-transform infrared spectroscopy, methylation, and nuclear magnetic resonance analyses. The Mws of GRO-N and GP-N were 1121.0 Da and 12,791.0 Da, respectively. Both had major chain structures comprising α-D-Glcp-(1→, →4)-α-D-Glcp-(1→, and →4)-α/β-D-Glcp, with branch points at →4,6)-α-D-Glcp-(1→. Moreover, the branched chain of GRO-N was α-D-Glcp-(1→ and →6)-α-D-Glcp-(1→. The branched chain of GP-N was α-D-Glcp-(1→ and →4)-α-D-Glcp-(1→. GRO-N, with a lower Mw and more diverse glycosidic bonds, exhibited higher antioxidant, hypoglycemic, and immune activities than GP-N. Cell viability peaked (202.81 ± 4.80 %) at a GRO-N concentration of 200 μg/mL. These findings provide a theoretical basis for further utilization of ginseng residual saccharides.

Salt stress has been found to enhance the quality of certain plants, yet its influence on fruit flavor remains largely unexplored. Our study probes the impact of salinity on the nutritional and flavor profile of tomatoes. Tomato plants were exposed to 0, 30, 50, 70, 90, and 110 mM of NaCl. Moderate salinity levels (50-70 mM) were found to boost the nutritional value of tomatoes, with increases in soluble solids, protein, and sugar levels. However, the concentration of key minerals such as K, Mg, and Mn declined with escalating salinity. Furthermore, the number of volatile compounds has increased, and the content of different types (alcohols, aldehydes, esters, etc.) has also significantly increased. Salinity stress also significantly influenced the levels of characteristic volatile compounds, especially hexanal, phenylethyl alcohol, and 6-methyl-5-hepten-2-one. Overall, these results will provide valuable strategies for producing high-quality tomatoes.

The golden apple snail (GAS, Pomacea canaliculata) has invaded mangrove forests. The effect of water contaminated by metabolic activity of GAS feeding on Acanthus ilicifolius (T1), Sonneratia apetala (T2), and without food (CK) on the native mangrove black helmet snail (BHS, Neritina pulligera) was investigated under salinity conditions. The GAS deteriorated saline water quality (2.5‱). DO contents in T1 and T2 approached zero at 9 d. Compared to CK, the contents of COD, total N, NH4+, NO3-, and total P of the contaminated water in T1 increased by 297%, 205%, 262%, 210%, and 518% after 9 d, while these indicators in T2 increased by 74%, 31%, 57%, 326%, and 154%, respectively. The LC50 of the contaminated water in T1 against the BHS reached 22.72%. The weight of the BHS exposed to the 100% contaminated water in T1 and T2 significantly decreased after exposure. The content of GPT of the BHS exposed to the 100%-contaminated water in T1 and T2 increased by 55% and 26%, while the MDA content increased by 38% and 34%. The 100%-contaminated water in T1 led to cell degeneration and incomplete structure in the hepatopancreas tissue of the BHS. The GAS feeding on holly mangroves can compete against native mangrove snails through water deterioration.

The pectic polysaccharide WTRP-A0.2b (43 kDa) has been isolated from Typhonii rhizoma and analyzed in terms of its structural features, anti-tumor activities and mechanism of action. NMR, FT-IR, monosaccharide composition, and enzymology demonstrate that WTRP-A0.2b is composed of rhamnogalacturonan I (RG-I), rhamnogalacturonan II (RG-II) and homogalacturonan (HG) domains with mass ratios of 3.7:1:1.7, respectively. The RG-I domains contain a highly branched structure that is substituted primarily with β-D-1,4-galactan, α-L-1,5-arabinan, and AG-II. The HG domains contain un-esterified and methyl-esterified and/or acetyl-esterified oligogalacturonides with a degree of polymerization of 1-8. In vitro experiments demonstrate that WTRP-A0.2b inhibits proliferation of K562 cells by inducing mitochondrial damage and suppressing glycolysis. This activity promotes mitochondrial permeability, increases production of reactive oxygen species (ROS), boosts extracellular oxygen consumption and adenosine triphosphate (ATP) content, while it decreases uncoupling protein-2 (UCP2) expression and lactic acid content. Our results provide valuable insight for screening natural polysaccharide-based anti-tumor effects of polysaccharides from Typhonii rhizoma.

Human serum albumin (HSA) is the most abundant protein in human plasma playing essential roles in transporting various biomolecules, metal ions, therapeutic agents, and metabolites. Additionally, it is crucial for maintaining oncotic pressure, scavenging free radicals, and preventing protein aggregation. Accurate quantification of HSA is vital for diagnosing various conditions, including hypertension, diabetes mellitus (DM), liver disorders, and renal diseases. While prevalent in clinical laboratories, traditional dye-binding methods have notable limitations: they can be time-consuming, lack sensitivity, and may suffer from interference from other serum components. These methods often require complex sample preparation and do not readily lend themselves to rapid or point-of-care testing (POCT). Consequently, there is a pressing need for innovative techniques that are rapid, cost-effective, and user-friendly. This review explores various dyes utilized for HSA determination, categorized into groups such as sulfonphthaleins, phenolphthaleins, azo dyes, etc., and provides a historical overview of the limitations of these methods. We critically assess the pros and cons of traditional dye-binding assays and emphasize the potential of emerging technologies, including microfluidic systems, smartphone-based detection, and nanopaper sensors, to address these gaps and enhance the efficiency and accessibility of HSA quantification in clinical settings.

This study aimed to investigate the regulatory effects of exogenous hydrogen sulfide (H2S) on seed germination, seedling growth, and reactive oxygen species (ROS) homeostasis in alfalfa under chromium (Cr) ion (III) stress.

The effects of 0-4 mM Cr(III) on the germination and seedling growth of alfalfa were first assessed. Subsequently, following seed NaHS immersion, the influence of H2S on alfalfa seed germination and seedling growth under 2 mM Cr(III) stress was investigated, and the substance contents and enzyme activities associated with ROS metabolism were quantified.

Compared to the control group, alfalfa plant germination was delayed under 2 mM Cr(III) stress for up to 48 h (p < 0.05). At 120 h, the total seedling length was approximately halved, and the root length was roughly one-third of the control. Treatment with 0.02-0.1 mM NaHS alleviated the delay in germination and root growth inhibition caused by 2 mM Cr(III) stress, resulting in an increased ratio of root length to hypocotyl length from 0.57 to 1 above. Additionally, immersion in 0.05 mM NaHS reduced hydrogen peroxide (H2O2) and oxygen-free radicals (O2· -) levels (p < 0.05), boosted glutathione (GSH) levels (p < 0.05), and notably enhanced catalase (CAT), ascorbate peroxidase (APX), and glutathione reductase (GR) activities (p < 0.05) compared to the 2 mM Cr(III) stress treatment group.

Seed immersion in NaHS mitigated the delay in germination and inhibition of root elongation under 2 mM Cr(III) stress. This effect is likely attributed to the regulation of intracellular ROS homeostasis and redox balance through enzymatic and non-enzymatic systems; thus, providing a potential mechanism for combating oxidative stress.

Ammonia is a critical pollutant in aquatic environments, posing significant risks to aquaculture by accumulating in culture systems due to fish excretion and organic matter decomposition. This study investigated the effects of ammonia toxicity on juvenile largemouth bass (Micropterus salmoides) under varying salinity conditions (0 and 5 psu), focusing on physiological responses and gut microbiota changes. Results indicated that ammonia exposure led to increased mortality, oxidative stress, liver damage, and significant shifts in gut microbial communities, especially under freshwater conditions. Elevated salinity mitigated these effects by reducing the bioavailability of toxic un-ionized ammonia (UIA) and enhancing the fish's physiological resilience, particularly in the kidney and intestine. Ammonia exposure significantly increased the IBR index values in all three organs, with the gills showing the most pronounced stress response, followed by the kidney and intestine. Salinity had a significant mitigating effect by reducing the oxidative stress response in comparison to freshwater conditions. However, in the gills, the protective effect of salinity was not enough to fully counteract the oxidative stress induced by ammonia. Ammonia exposure in freshwater favored pathogenic gut bacteria genera such as Aeromonas, while higher salinity enriched stress-resistant genera like Ralstonia and Klebsiella. These findings contribute to a better understanding of the interaction between salinity and ammonia toxicity, suggesting that moderate salinity increases within the fish's tolerance range could be an effective strategy in aquaculture to reduce ammonia toxicity and promote fish health.

Here, we present an in vitro protocol to assay mRNA translation inhibitors using the fluorescent assembly of split-GFP for translation test (FAST), based on the small fragment GFP11 binding to GFP1-10fast. We detail the expression and purification of the GFP1-10fast protein, DNA template amplification, in vitro GFP11-tagged CspA synthesis, FAST detection of the GFP11-tagged protein, and optional recovery of the fluorescent complex. In vitro synthesis of GFP11 maximizes the molar yield of synthesized proteins, providing enhanced sensitivity to test translation inhibitors. For complete details on the use and execution of this protocol, please refer to Pham et al.1.

This study aimed to extract and characterize polysaccharides from Arthrospira cell residue and evaluate their application in yogurt. Four Arthrospira polysaccharides (APP-50, APP-60, APP-70, and APP-80) were obtained by different ethanol concentrations. With the increase in ethanol concentration, the component peaks of polysaccharide became less and the components were simpler. The results showed that APP-60 had the highest neutral sugar content and the densest spherical structure. APP-50 had the highest protein content, the strongest antioxidant capacity, the porous structure, and the structure was incomplete. The addition of polysaccharides increased the viscosity, storage modulus, loss modulus, and particle size of yogurt, and improved the stability of yogurt during long-term storage. The microstructure of yogurt with added polysaccharides was tighter and more orderly than that of the control yogurt. This study demonstrated that Arthrospira polysaccharides could be used as functional ingredients to enhance the quality and nutritional value of yogurt.

The N-terminal regions of SLC6 transporters are sequentially unrelated, and the majority of such transporters contain only relatively short peptide N-terminal extensions. Currently, it is not clear if a diversity of N-terminal sequences represents diverse functions among the transporters or if there are common functions hidden behind similar, as yet unidentified, structures. Using alignment of amino acid sequences with the hydropathy plot, disorder prediction, and calpain recognition sites, we show that common structural features among the N-termini of some transporters might exist.We previously showed that polymeric neurotransmitter transporter N-termini exhibit very similar profiles of dynamic, time-dependent 465-595-350-750 nm absorbance metachromasia in the Bradford assay. Here we report that under certain mild denaturing conditions, filamentous aggregation of glutathione S-transferase (GST) protein results in similar near-infrared metachromasia. This effect was eliminated by further GST protein denaturation and solubilization. The results suggest that aggregation of partially denatured GST stabilizes Coomassie dye docking sites, producing a near-infrared absorbance shift similar to that observed in the polymeric unstructured N-termini of transporters.

Microbial remediation of organically combined contaminated sites is currently facing technical challenges. White rot fungi possess broad-spectrum degradation capabilities, but most of the studies are conducted on polluted water bodies, and few research focus on the degradation of combined organically contaminated soils. This study aimed to investigate the physiological changes in Trametes versicolor to enhance its simultaneous degradation ability towards benzo(a)pyrene (BaP) and TPH. The results demonstrated that Trametes versicolor, when subjected to liquid fermentation, achieved an 88.08% degradation of individual BaP within 7 days. However, under the combined contamination conditions of BaP and TPH, the BaP degradation rate decreased to 69.25%, while the TPH degradation rate was only 16.95%. Furthermore, the degradation rate of BaP exhibited a significant correlation with the extracellular protein concentration and laccase activities. Conversely, the TPH degradation rate exhibited a significant and positive correlation with the intracellular protein concentration. Solid-state fermentation utilizing fungal agents proved to be the most effective method for removing BaP and TPH, yielding degradation rates of 56.16% and 15.73% respectively within 60 days. Overall, Trametes versicolor demonstrated a commendable capability for degrading combined PAHs-TPH pollutants, thereby providing theoretical insights and technical support for the remediation of organically combined contaminated sites.

The challenge of soil salinization and alkalization, with its significant impact on crop productivity, has raised growing concerns with global population growth and enhanced environmental degradation. Although arbuscular mycorrhizal fungi (AMF) and calcium ions (Ca2+) are known to enhance plant resistance to stress, their combined effects on perennial ryegrass' tolerance to salt and alkali stress and the underlying mechanisms remain poorly understood. This study aimed to elucidate the roles of Arbuscular mycorrhizal (AM) fungus Rhizophagus irregularis and exogenous Ca2+ application in molecular and physiological responses to salt-alkali stress. AM symbiosis and exogenous Ca2+ application enhanced antioxidant enzyme activity and non-enzymatic components, promoting reactive oxygen species (ROS) scavenging and reducing lipid peroxidation while alleviating oxidative damage induced by salt-alkali stress. Furthermore, they enhanced osmotic balance by increasing soluble sugar content (Proportion of contribution of the osmotic adjustment were 34∼38 % in shoots and 30∼37 % in roots) under salt stress and organic acid content (Proportion of contribution of the osmotic adjustment were 32∼36 % in shoots and 37∼42 % in roots) under alkali stress. Changes in organic solute and inorganic cation-anion contents contributed to ion balance, while hormonal regulation played a role in these protective mechanisms. Moreover, the protective mechanisms involved activation of Ca2+-mediated signaling pathways, regulation of salt-alkali stress-related genes (including LpNHX1 and LpSOS1), increased ATPase activity, elevated ATP levels, enhanced Na+ extrusion, improved K+ absorption capacity, and a reduced Na+/K+ ratio, all contributing to the protection of photosynthetic pigments and the enhancement of photosynthetic efficiency. Ultimately, the combined application of exogenous Ca2+ and AMF synergistically alleviated the inhibitory effects of salt-alkali stress on perennial ryegrass growth. This finding suggested that exogenous Ca2+ may participate in the colonization of perennial ryegrass plants by R. irregularis, while AM symbiosis may activate Ca2+ pathways. Consequently, the combined treatment of AM and Ca2+ is beneficial for enhancing plant regulatory mechanisms and increasing crop yield under salt-alkali stress.

Lipids and Ca2+ are involved as intermediate messengers in temperature-sensing signaling pathways. Arbuscular mycorrhizal (AM) symbiosis is a mutualistic symbiosis between fungi and terrestrial plants that helps host plants cope with adverse environmental conditions. Nonetheless, the regulatory mechanisms of lipid- and Ca2+-mediated signaling pathways in mycorrhizal plants under cold and heat stress have not been determined. The present work focused on investigating the lipid- and Ca2+-mediated signaling pathways in arbuscular mycorrhizal (AM) and non-mycorrhizal (NM) roots under temperature stress and determining the role of Ca2+ levels in AM symbiosis and temperature stress tolerance in perennial ryegrass (Lolium perenne L.) Compared with NM plants, AM symbiosis increased phosphatidic acid (PA) and Ca2+ signaling in the roots of perennial ryegrass, increasing the expression of genes associated with low temperature (LT) stress, including LpICE1, LpCBF3, LpCOR27, LpCOR47, LpIRI, and LpAFP, and high temperature (HT) stress, including LpHSFC1b, LpHSFC2b, LpsHSP17.8, LpHSP22, LpHSP70, and LpHSP90, under LT and HT conditions. These effects result in modulated antioxidant enzyme activities, reduced lipid peroxidation, and suppressed growth inhibition caused by LT and HT stresses. Furthermore, exogenous Ca2+ application enhanced AM symbiosis, leading to the upregulation of Ca2+ signaling pathway genes in roots and ultimately promoting the growth of perennial ryegrass under LT and HT stresses. These findings shed light on lipid and Ca2+ signal transduction in AM-associated plants under LT and HT stresses, emphasizing that Ca2+ enhances cold and heat tolerance in mycorrhizal plants.

Degradation of polysaccharides is an effective method to improve the physicochemical properties and biological activities. In this study, self-extracting ginseng oligosaccharides (SGOs) and commercial ginseng oligosaccharides (CGOs) were compared with self-extracting ginseng polysaccharides (SGPs) and commercial ginseng polysaccharides (CGPs). The four saccharides were composed of different types and proportions of monosaccharides. And the molecular weight (Mw) size order was SGP > CGP > CGO > SGO. The SGO and CGO had better solubility with smaller particle size, 97.63 ± 0.42 % and 96.23 ± 1.12 %, respectively. Fourier transform infrared, nuclear magnetic resonance, and X-ray diffraction spectroscopy characterized the structures of four saccharides. It was found that the structural features of saccharides did not change after enzymatic hydrolysis. The results of bioactivities showed that SGO and CGO had better antioxidant, hypoglycemic, and hypolipidemic activities. Compared with polysaccharides, oligosaccharides could significantly promote the proliferation and phagocytic ability of RAW 264.7 cells. Oligosaccharides induced RAW 264.7 cells to produce more NO and had better immune activity. Pearson's correlation coefficient analysis confirmed the bioactivities were negatively correlated with the Mw of ginseng saccharides. This study suggests that reducing the Mw of saccharides is an effective strategy to enhance their bioactivities.

N6-methyladenosine (m6A) is a widespread post-transcriptional modification in eukaryotic mRNAs. Proteins with the YTH structural domain act as m6A-binding proteins by recognizing the m6A modification and regulating mRNA through this recognition. In this study, SlYTHDF2, a prototypical m6A -binding protein gene in the YTH family was expressed in various tissues, and subcellular localization analyses indicated that the SlYTHDF2 protein was localized in the nucleus and cytoplasm. SlYTHDF2 knockout lines were obtained using CRISPR/Cas9 technology and showed the senesced leaves prematurely increased endogenous ABA accumulation compared with the wild type. Moreover, we found that dark promoted leaf senescence in SlYTHDF2 knockout lines and exogenous ABA further accelerated leaf senescence under dark conditions. The qRT-PCR analysis revealed significant alterations in the expression of genes associated with the ABA pathway. Relative to the wild type, the CR-slythdf2 plants exhibited reduced levels of photosynthetic pigments, higher accumulation of reactive oxygen species, and increased damage to cell membranes. Additionally, we discovered that SlYTHDF2 interacts with the chloroplast-binding protein SlRBCS3 through yeast two-hybrid and BiFC experiments. Overall, our data suggest the important role of SlYTHDF2 in regulating tomato leaf senescence.

Cordyceps sinensis, a traditionally prized medicinal fungus, contains polysaccharides as one of its main bioactive constituents, known for their significant immunomodulatory properties. In this study, we systematically investigated the composition and structure of Cordyceps sinensis polysaccharide, followed by an evaluation of its therapeutic effect on depression using a chronic restraint stress-induced depression model. The polysaccharide CSWP-2, extracted via hot water, precipitated with ethanol, and purified using DEAE-cellulose column chromatography from Cordyceps sinensis, is primarily composed of glucose, mannose, and galactose, with α-1,4-D-glucan as its major structural component. Behavioral tests, immunological profiling, metabolomics, and gut microbiota analyses indicated a notable ameliorative effect of CSWP-2 on depressive-like symptoms in mice. Furthermore, the action of CSWP-2 may be attributed to the modulation of the gut microbiome's abundance and its metabolic impacts, thereby transmitting signals to the host immune system and exerting immunomodulatory activity, ultimately contributing to its antidepressant effects.

Sipunculus nudus (S. nudus), an edible marine invertebrate, is rich in myofibrillar proteins. However, its extremely low water solubility and relatively firm texture limit its practical applications. This study aimed to investigate the consequences of different ultrasound amplitude treatments on the structure, functional properties, and digestive characteristics of S. nudus salt soluble protein (SSP). The results showed that ultrasound treatment significantly reduced the particle size, surface tension, and the unordered structure of SSP, while having not impact the zeta potential. Additionally, the results of infrared spectroscopy and intrinsic fluorescence spectrum revealed that ultrasound treatment enhanced the hydrogen bonding and hydrophobic interaction within the components of SSP, leading to a more compact and uniformly distributed protein structure. These changes increased the solubility (increased from 12.07 % to 37.59 %) and optimized the functional properties of SSP (foamability and emulsifiability). Further, the results of in vitro digestion simulation revealed that the antioxidant proteopeptides of SSP were mainly produced in the small intestine, with the ABTS+ radical scavenging capacity ranging from 140 to 170 μg Trolox/mL. Additionally, the antioxidant activity of the digestive fluid was enhanced with increasing ultrasound amplitude. This work linked structural changes in denatured proteins to their functional properties and digestive characteristics. This study provided a new direction for developing easily digestible food ingredients.

Considering an ever-growing global population, which hit 8 billion people in the fall of 2022, it is essential to find solutions to avoid croplands competition between human food and animal feed. Agricultural co-products such as soybean meals have become important components of the circular economy thanks to their use in animal feed. Their implementation was made possible by the addition of exogenous enzymes in the diet of monogastric animals, especially fungal carbohydrate-active enzymes (CAZymes). Here, we describe a time-course production and analysis of Aspergillus terreus secretomes for the identification of CAZymes able to enhance the digestibility of soybean meals. Functional assays revealed that the release of nutrients and the degradation of pectins in soybean meals can be tightly interconnected. Using a comparative proteomics approach, we identified several fungal pectin-degrading enzymes leading to increased assimilable nutrients in the soluble fraction of soybean meals. Our results reinforce the importance of deconstructing pectic polysaccharides in feedstuffs and contribute to sharpen our understanding of the fungal enzymatic interplays involved in pectin hydrolysis.IMPORTANCEIn the present study, we developed a strategy to identify the key fungal enzymatic activities involved in the improvement of soybean meal (SBM) digestibility. Our data unravel the importance of pectin degradation for the release of nutrients from SBM and provide some insights regarding the degradation of rhamnogalacturonan-I (RG-I) by ascomycetes. Indeed, the hydrolysis of pectins and RG-I by human microbiota is well documented in the literature, but our knowledge of the fungal CAZymes at play for the degradation of soybean pectins remains hitherto underexplored. Due to its wide use in animal feed, improving the digestibility of SBM by enzymatic treatments is a current challenge for feed additive suppliers. Since non-starch polysaccharides and pectins have often been reported for their anti-nutritional role in SBM, we believe this study will provide new avenues toward the improvement of enzymatic cocktails for animal nutrition and health.

Here, we report the design and synthesis of a D⋯π⋯A-based fluorescent probe, (E)-4-(4-(dibutylamine)-2-hydroxystyryl)-1-methylquinolin-1-ium (DHMQ), which is nonfluorescent in ∼100% PBS buffer medium due to a twisted intra molecular charge transfer (TICT) phenomenon and it becomes highly fluorescent (∼149 fold) in the presence of human serum albumin (HSA), owing to the restriction of its intramolecular free rotation inside the hydrophobic binding cavity of HSA. The site-selective fluorescence displacement assay and molecular docking studies clearly reveal that DHMQ selectively binds at subdomain IB of HSA. The 3σ/slope method was adopted to determine the limit of detection (LOD) value, which was as low as 2.39 nM in ∼100% PBS medium, indicating its high sensitivity towards HSA. The low dissociation constant value [Kd = (1.066 ± 0.017) μM] suggests a strong complexation between the DHMQ and HSA. Importantly, it has been demonstrated that DHMQ is capable of detecting HSA in real human serum and urine samples and was found to be suitable for live cell imaging of HSA.

This study investigated the hypoglycemic mechanism of guava polysaccharides (GP) through the gut microbiota (GM) and related metabolites. Our findings demonstrated that GP significantly mitigated high-fat diet- and streptozotocin-induced hyperglycemia, insulin resistance, hyperlipidemia, elevated alanine aminotransferase, high hepatic inflammation levels, and prevented pancreatic atrophy and hepatomegaly. Interestingly, the benefits of GP were attributed to alterations in the GM. GP decreased the ratio of Firmicutes to Bacteroidetes, significantly inhibiting deleterious bacteria, including Uncultured_f_Desulfovibrionaceae, Bilophila, and Desulfovibrio, while promoting the proliferation of probiotic Bifidobacterium and Bacteroides. In addition, GP promoted the generation of short-chain fatty acids. Notably, the arachidonic acid (AA) metabolism pathway was enriched in liver metabolites. GP significantly elevated hepatic AA and 15-hydroxyeicosatetraenoic acid, while reducing prostaglandin E2 and 5- and 12-hydroxyeicosatetraenoic acid. This modulation is accompanied by the downregulation of hepatic cyclooxygenase-1, 12-lipoxygenase, P38, and c-Jun N-terminal kinase mRNA expression, and the upregulation of cytochrome P4502J5 and insulin receptor substrate 1/2 mRNA expression. However, GP antibiotic treatment did not induce significant alterations in FBG and AA levels or gene expression. Overall, our findings suggest that the hypoglycemic effect of GP may be intricately linked to alterations in AA metabolism, which depends on the GM.

Dried shiitake mushrooms offer rich nutritional value and unique sensory properties, prompting further investigation. The effects of different drying techniques (hot air drying (HAD), infrared hot air drying (IRHAD), pulsed vacuum drying (PVD), vacuum freeze drying (VFD), and natural drying (ND)) combined with enzymatic hydrolysis on the release of flavor compounds and nutrients from shiitake mushrooms were explored. The combination of HAD with cellulase hydrolysis yielded notably high levels of umami amino acids (5.4723 ± 0.1501 mg/g) and 5'-nucleotides (4.0536 ± 0.0062 mg/g), and superior volatile flavors. Combined with cellulase hydrolysis, IRHAD achieved the highest level of total sugars (6.57 ± 0.34 mg/mL), VFD resulted in the greatest soluble protein content (153.21 ± 0.23 μg/mL), PVD yielded the highest total phenolics content (93.20 ± 0.41 μg GAE/mL), and ND produced the maximum reducing sugar content (5.79 ± 0.13 mg/mL). This study addresses crucial gap in the post-drying processing of shiitake mushrooms, offering valuable insights for further product development of shiitake mushrooms.

The bHLH transcription factors are important plant regulators against abiotic stress and involved in plant growth and development. In this study, SlALC, a gene coding for a prototypical DNA-binding protein in the bHLH family, was isolated, and SlALC-overexpression tomato (SlALC-OE) plants were generated by Agrobacterium-mediated genetic transformation. SlALC transgenic lines manifested higher osmotic stress tolerance than the wild-type plants, estimated by higher relative water content and lower water loss rate, higher chlorophyll, reducing sugar, starch, proline, soluble protein contents, antioxidant enzyme activities, and lower MDA and reactive oxygen species contents in the leaves. In SlALC-OE lines, there were more significant alterations in the expression of genes associated with stress. Furthermore, SlALC-OE fruits were more vulnerable to dehiscence, with higher water content, reduced lignin content, SOD/POD/PAL enzyme activity, and lower phenolic compound concentrations, all of which corresponded to decreased expression of lignin biosynthetic genes. Moreover, the dual luciferase reporter test revealed that SlTAGL1 inhibits SlALC expression. This study revealed that SlALC may play a role in controlling plant tolerance to drought and salt stress, as well as fruit lignification, which influences fruit dehiscence. The findings of this study have established a foundation for tomato tolerance breeding and fruit quality improvement.

An alkali-soluble β-glucan (AHEP-A-b, 20 kDa) purified from Hericium erinaceus fruiting bodies, was structurally characterized and examined for antioxidant activity. Methylation analysis and NMR spectroscopy show that the backbone of AHEP-A-b is composed of (1→6)-linked-D-β-glucopyran residues, branched at O-3 of glucopyranose (Glcp) residues with [→3)-β-D-Glcp-(1→] oligosaccharides or single unit of β-Glcp. Periodate oxidation analysis and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) indicate that the degree of polymerization (DP) of [→3)-β-D-Glcp-(1→] side chains is 2 to 8. Functionally, AHEP-A-b is a relatively strong antioxidant as demonstrated by using 2, 2'-azino-bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) free radical (ABTS·+), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, and hydroxyl radicals scavenging assays. The present study lays the foundation for further studies into structure-activity relationships of polysaccharides from H. erinaceus.

The growing demand for effective alternatives to red blood cells (RBCs) has spurred significant research into hemoglobin (Hb)-based oxygen carriers (HBOCs). Accurate characterization of HBOCs-including Hb content, encapsulation efficiency, and yield-is crucial for ensuring effective oxygen delivery, economic viability, and the prevention of adverse effects caused by free Hb. However, the choice of quantification methods for HBOCs is often driven more by tradition than by a thorough assessment of available options. This study meticulously compares various UV-vis spectroscopy-based methods for Hb quantification, focusing on their efficacy in measuring Hb extracted from bovine RBCs across different concentration levels. The findings identify the sodium lauryl sulfate Hb method as the preferred choice due to its specificity, ease of use, cost-effectiveness, and safety, particularly when compared to cyanmethemoglobin-based methods. Additionally, the study discusses the suitability of these methods for HBOC characterization, emphasizing the importance of considering carrier components and potential interferences by analyzing the absorbance spectrum before selecting a method. Overall, this study provides valuable insights into the selection of accurate and reliable Hb quantification methods, which are essential for rigorous HBOC characterization and advancements in medical research.

Polyphenol oxidase (PPO) is an industrially important enzyme associated with browning reactions. In the present study, a set of ten new dihydropyridine [2,3-d] pyrimidines (TD-Hid-1-10) were synthesized and was found to be proven characteristically by 1H NMR, 13C NMR, IR, elemental analysis, and assessed as possible PPO inhibitors. PPO was purified from banana using three-phase partitioning, achieving an 18.65-fold purification and 136.47% activity recovery. Enzyme kinetics revealed that the compounds TD-Hid-6 and TD-Hid-7 are to be the most potent inhibitors, exhibiting mixed-type inhibition profile with IC50 values of 1.14 µM, 5.29 µM respectively against purified PPO enzyme. Electronic structure calculations at the B3LYP/PBE0 level of theories using def-2 SVP, def2-TZVP basis sets with various molecular descriptors characterized the electronic behavior of studied derivatives TD-Hid-1-10. Molecular electrostatic potential (MEP) and reduced density gradient analyses of RDG-NCI provided insights into charge distributions and weak intermolecular interactions. Docking study simulations predicted binding poses within crucial amino acid sequence in the 2y9x enzyme's active site, which is typically similar in sequence to the PPO form is not allowed. Ligands were analysed in terms of binding energies, inhibitor concentrations (mM) and various molecular interactions such as H-bonds, H-carbon, π-carbon, π-sigma, π-sigma, π-π T-shaped, π-π stacked, π-alkyl, Van der Waals and Cu interactions. The lowest binding energy (-7.83 kcal/mol) and the highest inhibitory effect (1.83 mM) were shown by the ligand Td-Hid-6, which forms H-bonds with Met280 and Asn260, exhibits π-sigma interactions with His61 and π-alkyl interactions with Val283. Other ligands also showed different interactions with various amino acids; for example, the Td-Hid-1 ligand formed H-bonds with His244 and showed π-sigma interactions with His244 and Val283.

Peanut is an economically important crop, but it is susceptible to Cr contamination. In this study, we used peanut as experimental material to investigate the effects of exogenous P, Se interacting with Cr on the nutrient growth and antioxidant system of peanut seedlings by simulating Cr (0 μM, 50 μM, and 100 μM) stress environment. The results showed that exogenous P, Se supply could mitigate irreversible damage to peanut seedlings by altering the distribution of Cr in roots and aboveground, changing root conformation, and repairing damaged cells to promote growth. When the Cr concentration is 100 μM, it exhibits the highest toxicity. Compared to the control group P and Se (0 MM), the treatment with simultaneous addition of P + Se (0.5 + 6.0) resulted in a significant increase in root length and root tip number by 248.7% and 127.4%, respectively. Additionally, there was a 46.9% increase in chlorophyll content, a 190.2% increase in total surface area of the seedlings, and a respective increase of 149.1% and 180.3% in soluble protein content in the shoot and roots. In addition, by restricting the absorption of Cr and reducing the synthesis of superoxide dismutase SOD (Superoxide dismutase), CAT (Catalase), POD (Peroxidase), and MDA (Malonaldehyde), it effectively alleviates the oxidative stress on the antioxidant system. Therefore, the exogenous addition of P (0.5 MM) and Se (6.0 MM) prevented the optimal concentration of chromium toxicity to peanuts. Our research provides strong evidence that the exogenous combination of P and Se reduces the risk of peanut poisoning by Cr, while also exploring the optimal concentration of exogenous P and Se under laboratory conditions, providing a basis for further field experiments.

Cadmium, a hazardous environmental contaminant, is associated with metabolic disease development. The dose with the lowest observable adverse effect level (LOAEL) has not been studied, focusing on its effect on the pancreas. We aimed to evaluate the pancreatic redox balance and heat shock protein (HSP) expression in islets of Langerhans of male Wistar rats chronically exposed to Cd LOAEL doses, linked to their survival. Male Wistar rats were separated into control and cadmium groups (drinking water with 32.5 ppm CdCl2). At 2, 3, and 4 months, glucose, insulin, and cadmium were measured in serum; cadmium and insulin were quantified in isolated islets of Langerhans; and redox balance was analyzed in the pancreas. Immunoreactivity analysis of p-HSF1, HSP70, HSP90, caspase 3 and 9, and cell survival was performed. The results showed that cadmium exposure causes a serum increase and accumulation of the metal in the pancreas and islets of Langerhans, hyperglycemia, and hyperinsulinemia, associated with high insulin production. Cd-exposed groups presented high levels of reactive oxygen species and lipid peroxidation. An augment in MT and GSH concentrations with the increased enzymatic activity of the glutathione system, catalase, and superoxide dismutase maintained a favorable redox environment. Additionally, islets of Langerhans showed a high immunoreactivity of HSPs and minimal immunoreactivity to caspase associated with a high survival rate of Langerhans islet cells. In conclusion, antioxidative and HSP pancreatic defense avoids cell death associated with Cd accumulation in chronic conditions; however, this could provoke oversynthesis and insulin release, which is a sign of insulin resistance.

A fundamental question in developmental biology is how to regulate grain size to improve crop yields. Despite this, little is still known about the genetics and molecular mechanisms regulating grain size in crops. Here, we provide evidence that a putative protein kinase-like (OsLCD3) interacts with the S-adenosyl-L-methionine synthetase 1 (OsSAMS1) and determines the size and weight of grains. OsLCD3 mutation (lcd3) significantly increased grain size and weight by promoting cell expansion in spikelet hull, whereas its overexpression caused negative effects, suggesting that grain size was negatively regulated by OsLCD3. Importantly, lcd3 and OsSAMS1 overexpression (SAM1OE) led to large and heavy grains, with increased ethylene and decreased polyamines production. Based on genetic analyses, it appears that OsLCD3 and OsSAMS1 control rice grain size in part by ethylene/polyamine homeostasis. The results of this study provide a genetic and molecular understanding of how the OsLCD3-OsSAMS1 regulatory module regulates grain size, suggesting that ethylene/polyamine homeostasis is an appropriate target for improving grain size and weight.

MutT proteins belong to the Nudix hydrolase superfamily that includes a diverse group of Mg2+ requiring enzymes. These proteins use a generalized substrate, nucleoside diphosphate linked to a chemical group X (NDP-X), to produce nucleoside monophosphate (NMP) and the moiety X linked with phosphate (XP). E. coli MutT (EcoMutT) and mycobacterial MutT1 (MsmMutT1) belong to the Nudix hydrolase superfamily that utilize 8-oxo-(d)GTP (referring to both 8-oxo-GTP or 8-oxo-dGTP). However, predominant products of their activities are different. While EcoMutT produces 8-oxo-(d)GMP, MsmMutT1 gives rise to 8-oxo-(d)GDP. Here, we show that the altered cleavage specificities of the two proteins are largely a consequence of the variation at the equivalent of Gly37 (G37) in EcoMutT to Lys (K65) in the MsmMutT1. Remarkably, mutations of G37K (EcoMutT) and K65G (MsmMutT1) switch their cleavage specificities to produce 8-oxo-(d)GDP, and 8-oxo-(d)GMP, respectively. Further, a time course analysis using 8-oxo-GTP suggests that MsmMutT1(K65G) hydrolyses 8-oxo-(d)GTP to 8-oxo-(d)GMP in a two-step reaction via 8-oxo-(d)GDP intermediate. Expectedly, unlike EcoMutT (G37K) and MsmMutT1, EcoMutT and MsmMutT1 (K65G) rescue an E. coli ΔmutT strain, better by decreasing A to C mutations.

The extract of Dendrobium huoshanense, a traditional Chinese medicinal and food homologous plant belonging to the family Orchidaceae, was previously reported to have hypoglycemic and antioxidant effects. In this study, the direct effects of polysaccharide (DHP) and non-polysaccharide (NDHP) components of D. huoshanense, as well as its water extract (DHWE) were compared with that of metformin (an antidiabetic drug) on the gut microbiota (collected from fecal flora) of rats with streptozotocin-induced type 1 diabetes (T1D) using an in vitro fermentation method. The results showed that DHWE, DHP, and NDHP reduced pH and increased bacterial proliferation and short-chain fatty acid (SCFA) content in fermentation broth. DHWE, DHP, NDHP and metformin promoted the production of acetic and propionic acid, acetic acid, propionic acid and butyric acid, and propionic acid, respectively. DHWE, DHP, and NDHP reduced the abundance of Proteobacteria (subdominant pathogenic bacteria) and increased the abundance of Firmicutes (dominant beneficial gut bacteria). NDHP also reduced the abundance of Bacteroidetes (beneficial and conditional pathogenic). Metformin increased the abundance of Proteobacteria and reduced the abundance of Firmicutes and Bacteroidetes. At the genus level, NDHP promoted the proliferation of Megamonas and Megasphaera and decreased harmful bacteria (e.g., Klebsiella), and DHP increased the abundance of Prevotellaceae (opportunistic and usually harmless). By contrast, metformin increased the abundance of harmful bacteria (e.g., Citrobacter) and reduced the abundance of beneficial bacteria (e.g., Oscillospira). Our study indicates that DHWE, DHP, and NDHP are potentially more beneficial than metformin on the gut microbiota of T1D rats in vitro.

Pollen, as the male gametophyte, carries half of plant genetic information and is an important source of germplasm. The cryopreservation of pollen can not only preserve germplasm, but also solve the problem of time and space barrier in crossbreeding. So it is of great significance to explore the mechanism of pollen viability maintenance after cryopreservation. In this paper, 10 cultivars of Paeonia lactiflora with different fresh pollen viability that did not change after cryopreservation were taken as objects and the effects of pollen inclusions such as soluble sugar, starch, soluble protein, free amino acids, and proline were explored. The results showed that: (1) The contents of pollen inclusions in the fresh pollen of 10 cultivars were different. After cryopreservation, the contents of starch and free amino acids significantly decreased in 10 cultivars, and the soluble sugar, soluble protein, and proline varied with cultivars. (2) Correlation analysis showed that fresh pollen viability was significantly positively correlated with the soluble sugar (R-values of 0.630) and starch content (R-values of 0.694) in fresh pollen. But after cryopreservation pollen viability was only significantly positively correlated with the starch content (R-values of 0.725). These results suggest that the effects of pollen inclusions on pollen vitality are different before and after cryopreservation. The fresh pollen with higher soluble sugar and starch is more vital. But after cryopreservation, the pollen with high starch content has higher viability. The maintenance of stable pollen viability after cryopreservation appears to be related to starch content or starch metabolism, which requires further to study for a final determination.

Polymerized guluronates (polyG)-specific alginate lyase with lower polymerized mannuronates (polyM)-degrading activity, superior stability, and clear action mode is a powerful biotechnology tool for the preparation of AOSs rich in M blocks. In this study, we expressed and characterized a polyG-specific alginate lyase OUC-FaAly7 from Formosa agariphila KMM3901. OUC-FaAly7 belonging to polysaccharide lyase (PL) family 7 had highest activity (2743.7 ± 20.3 U/μmol) at 45 °C and pH 6.0. Surprisingly, its specific activity against polyG reached 8560.2 ± 76.7 U/μmol, whereas its polyM-degrading activity was nearly 0 within 10 min reaction. Suggesting that OUC-FaAly7 was a strict polyG-specific alginate lyase. Importantly, OUC-FaAly7 showed a wide range of temperature adaptations and remarkable temperature and pH stability. Its relative activity between 20 °C and 45 °C reached >90 % of the maximum activity. The minimum identifiable substrate of OUC-FaAly7 was guluronate tetrasaccharide (G4). Action process and mode showed that it was a novel alginate lyase digesting guluronate hexaose (G6), guluronate heptaose (G7), and polymerized guluronates, with the preferential generation of unsaturated guluronate pentasaccharide (UG5), although which could be further degraded into unsaturated guluronate disaccharide (UG3) and trisaccharide (UG2). This study contributes to illustrating the catalytic properties, substrate recognition, and action mode of novel polyG-specific alginate lyases.