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The rich active hydroxyl groups on starch nanocrystals (SNC) surface limits its dispersion and stability in the aqueous phase. To address this issue, ozone modification for 0 (SNC), 0.5 (SNC-1), 1 (SNC-2), 1.5 (SNC-3), and 2 h (SNC-4) as compared to conventionally chemical methods was applied to functionally modify the SNC. The impact of ozone treatment on the structural and surface characteristics of waxy rice starch nanocrystals. The findings revealed that longer ozone treatment durations favored the formation of carbonyl groups in starch molecules. Initially, ozone oxidized the hydroxyl group of the macromolecule. Once the carbonyl groups formed, the cross-linking reaction occurred among starch nanocrystals through condensation reactions, leading to the increasing molecular orderliness. X-ray photoelectron spectroscopy, X-ray diffraction and Small-angle X-ray scattering analyses of SNC-2 supported this finding with a reduced O/C ratio, and implied that surface oxidation did not alter the crystal type but rather enhanced molecular hydration in an aqueous system, leading to increased interfacial thickness and fractal dimension. Additionally, ozone oxidation improved surface properties such as charge and hydrophobicity. Oxidized SNC also exhibited altered gelatinization properties due to surface degradation. This study offers a promising strategy for enhancing SNC surface properties, crucial for food science applications.
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Waxy rice starch (St) was modified by pre-OSA esterification reaction followed by ozone treatment. The molecular structure of this modified product (OSA-OSt) was characterized, and the thermal behaviors and its stabilized Pickering emulsion were evaluated. 1HNMR and XPS results discovered that ozone initially oxidized the hydroxyl groups in the amorphous region of starch (preferentially C2/C3) along with a degree of crosslinking, enhancing the molecular orderliness. This led to an increase in water-holding capability (29.15%) and swelling power (52.8 g/g), and a decrease in solubility (0.35%). TGA, RVA, and DSC indicated that oxidation-induced crosslinking within a brief treatment period enhanced the starch's thermal stability. The structural change enabled the formation of a weak gel structure during the heating process, which displayed high thermal and freeze-thaw stability. The work proves ozone is an effective way of improving the thermal behavior of OSA-starch and its emulsion for subsequent applications in numerous food products.
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Our previous study identified round scad neuroprotective peptides with different characteristics. However, the intrinsic relationship between their structure and bioactivity, as well as their bioavailability, remains unclear. The aim of this study is to elucidate the bioavailability of these peptides and their structure-activity relationship against neuroinflammation. Results showed that the SR and WCP peptides were resistant to gastrointestinal digestion. Additionally, peptides SR, WCP, and WCPF could transport Caco-2 monolayers as intact peptides. The permeability coefficients (Papp) of SR, WCP, and WCPF in Caco-2 monolayer were (1.53 ± 0.01) × 10-5, (2.12 ± 0.01) × 10-5, and (8.86 ± 0.03) × 10-7 cm/s, respectively. Peptides SR, WCP, and WCPF, as promising inhibitors of JAK2 and STAT3, could attenuate the levels of pro-inflammatory cytokines and regulate the NFκB and JAK2/STAT3 signaling pathway in LPS-treated BV-2 cells. WCPF exerted the highest anti-inflammatory activity. Moreover, bioinformatics, molecular docking, and quantum chemistry studies indicated that the bioactivity of SR was attributed to Arg, whereas those of WCP and WCPF were attributed to Trp. This study supports the application of round-scad peptides and deepens the understanding of the structure-activity relationship of neuroprotective peptides.
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Anti-Inflamatórios , Janus Quinase 2 , Peptídeos , Humanos , Relação Estrutura-Atividade , Peptídeos/química , Peptídeos/farmacologia , Células CACO-2 , Janus Quinase 2/metabolismo , Janus Quinase 2/química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Animais , Camundongos , Proteínas de Peixes/química , Proteínas de Peixes/farmacologia , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/química , Fator de Transcrição STAT3/genética , Simulação de Acoplamento Molecular , NF-kappa B/metabolismo , NF-kappa B/genética , NF-kappa B/químicaRESUMO
The hydrophilicity of gelatin films obviously limits their application. In this work, novel protonated chitin nanofiber was prepared with green methods, surficial deacetylation combined with acidic and mechanical treatment. Composite films with excellent water and oxygen barrier properties were successfully prepared by blending O/W Pickering emulsions stabilized by chitin nanofibers with gelatin substrates. The films were characterized by Fourier-transform infrared, X-ray diffraction, mechanical properties, water and oxygen permeability, moisture content, water solubility, water contact angle and optical properties. The results demonstrated that the amino groups of chitin nanofibers bound to the carboxyl groups of gelatin via electrostatic interactions, which contributing to the excellent mechanical and barrier properties of composite films. The elongation at break of composite film (the concentration of chitin nanofiber was 0.2 wt%) was 2.66 times of gelatin film. And the water vapor and oxygen permeability of composite films lowered to 65.9 % and 52.9 %, respectively. The introduction of O/W Pickering emulsion significantly enhanced the hydrophobicity of gelatin-based film and the chitin nanofibers played a positive role in stabilizing the gelatin chains to a certain extent. This study expands the application fields of gelatin-based films and provides valuable technical route for the preparation of barrier films.
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Quitina , Emulsões , Gelatina , Nanofibras , Oxigênio , Permeabilidade , Água , Gelatina/química , Quitina/química , Nanofibras/química , Emulsões/química , Água/química , Oxigênio/química , Interações Hidrofóbicas e Hidrofílicas , Solubilidade , Espectroscopia de Infravermelho com Transformada de FourierRESUMO
There are numerous studies on the application of soybean whey protein in three-dimensional (3D) printing. In this study, the effects of soybean meal particles (5%, 6%, 7%, 8%, 9%, and 10%) and oil-phase concentrations (70%, 72%, 74%, 76%, and 78%) on the stability and 3D-printing performance of a soybean-meal-based high-internal-phase emulsion were investigated. The results showed that the particle size of the emulsion decreased with increasing soybean meal particle concentration, and that increasing the concentration of the oil phase improved the viscoelasticity of the emulsion. Rheological tests further showed that the higher storage modulus of the emulsion indicated better support and stability. The emulsion with 8% soybean meal-particles and 76% oil-phase concentration exhibited the best printing effect. This study provides an effective solution for the preparation of stabilized high-internal-phase emulsions of soybean meal particles suitable for 3D printing.
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Emulsões , Glycine max , Tamanho da Partícula , Impressão Tridimensional , Reologia , Emulsões/química , Glycine max/química , Viscosidade , Proteínas do Soro do Leite/químicaRESUMO
To investigate the optimal delivery system of quercetin, in this paper, cellulose nanocrystals (CNCs) extracted from rice bran were used to stabilize the Pickering emulsion and Pickering emulsion gels (PEGs) with quercetin. To compare the emulsion properties, stability, antioxidation activity, encapsulation rate, and bioaccessibility of the quercetin, four emulsions of CNC Pickering emulsion (C), CNC Pickering emulsion with quercetin (CQ), CNC Pickering gel emulsion (CG), and CNC Pickering gel emulsions with quercetin (CQG) were prepared. All four emulsions exhibited elastic gel network structure and good stability. The quercetin significantly reduced the particle size, increased the stability, and improved the antioxidant capacity of CQ and CQG. Compared to C and CG, the ABTS+ radical scavenging capacities of CQ and CQG were respectively enhanced by 46.92% and 3.59%. In addition, CQG had a higher encapsulation rate at 94.57% and higher bioaccessibility (16.17) compared to CQ. This study not only indicated that CNC from rice bran could be exploited as an excellent stabilization particle for Pickering emulsions, but also provided a highly stable and bioaccessible delivery system for water-insoluble functional active factors.
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Three pairs of enantiomers (1-3)-the new 12R-aloesol (1a) and two new fatty acids (2 and 3)-and one new natural product (4) together three known compounds (5-7) were isolated from a coral-reef-derived Streptomyces sp. SCSIO 66814. Their structures were determined through extensive spectroscopic analysis, chiral analysis, and single-crystal X-ray diffraction data. Compounds 2 and 3 were presumed to be intermediates for further generating homononactic acid (5) and nonactic acid, and the latter two molecules were able to act as precursors to form macrotetrolides with remarkable biological activity. The isolation of related precursors, compounds 2-5, provided more evidence to support the proposal of a plausible biosynthetic pathway for nonactic acid and its homologs. Additionally, (+)-1 exhibited a weak activity against DPPH radicals.
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Antozoários , Cromonas , Streptomyces , Streptomyces/metabolismo , Streptomyces/química , Cromonas/química , Cromonas/isolamento & purificação , Cromonas/farmacologia , Estereoisomerismo , Antozoários/química , Animais , Cristalografia por Raios X , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/isolamento & purificação , Estrutura MolecularRESUMO
An ethyl acetate extract of a marine actinomycete strain, Nocardiopsis mentallicus SCSIO 53858, isolated from a deep-sea sediment sample in the South China Sea, exhibited anti-quorum-sensing (QS) activity against Chromobacterium violaceum CV026. Guided by the anti-QS activity, a novel active compound was isolated and purified from the extract and was identified as 2,3-dimethoxycinnamic acid (2,3-DCA) through spectral data analysis. At a concentration of 150 µg/mL, 2,3-DCA exhibited robust inhibitory effects on three QS-regulated traits of C. violaceum CV026: violacein production, swarming motility, and biofilm formation, with inhibition rates of 73.9%, 65.9%, and 37.8%, respectively. The quantitative reverse transcription polymerase chain reaction results indicated that 2,3-DCA can disrupt the QS system in C. violaceum CV026 by effectively suppressing the expression of QS-related genes, including cviR, vioA, vioB, and vioE. Molecular docking analysis revealed that 2,3-DCA hinders the QS system by competitively binding to the same binding pocket on the CviR receptor as the natural signal molecule N-hexanoyl-L-homoserine lactone. Collectively, these findings suggest that 2,3-DCA exhibits promising potential as an inhibitor of QS systems, providing a potential solution to the emerging problem of bacterial resistance.
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Antibacterianos , Chromobacterium , Indóis , Simulação de Acoplamento Molecular , Percepção de Quorum , Percepção de Quorum/efeitos dos fármacos , Chromobacterium/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/química , Actinobacteria/química , Cinamatos/farmacologia , Cinamatos/isolamento & purificação , Cinamatos/química , Biofilmes/efeitos dos fármacos , Sedimentos Geológicos/microbiologia , Organismos Aquáticos , ChinaRESUMO
Bafilomycins are macrocyclic polyketides with intriguing structures and therapeutic value. Genomic analysis of Streptomyces sp. SCSIO 66814 revealed a type I polyketide synthase biosynthetic gene cluster (BGC), namely blm, which encoded bafilomycins and featured rich post-modification genes. The One strain many compounds (OSMAC) strategy led to the discovery of six compounds related to the blm BGC from the strain, including two previously undescribed 6,6-spiroketal polyketides, streptospirodienoic acids D (1) and E (2), and four known bafilomycins, bafilomycins P (3), Q (4), D (5), and G (6). The structures of 1 and 2 were determined by extensive spectroscopic analysis, quantum calculation, and biosynthetic analysis. Additionally, the absolute configurations of the 6/5/5 tricyclic ring moiety containing six consecutive chiral carbons in the putative structures of 3 and 4 were corrected through NOE analysis, DP4+ calculation, and single-crystal X-ray diffraction data. Bioinformatic analysis uncovered a plausible biosynthetic pathway for compounds 1-6, indicating that both streptospirodienoic acids and bafilomycins were derived from the same blm BGC. Additionally, sequence analysis revealed that the KR domains of module 2 from blm BGC was B1-type, further supporting the configurations of 1-4. Notably, compounds 3 and 4 displayed significant cytotoxic activities against A-549 human non-small cell lung cancer cells and HCT-116 human colon cancer cells.
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Policetídeos , Streptomyces , Streptomyces/química , Streptomyces/metabolismo , Streptomyces/genética , Policetídeos/química , Policetídeos/farmacologia , Policetídeos/isolamento & purificação , Humanos , Estereoisomerismo , Ensaios de Seleção de Medicamentos Antitumorais , Estrutura Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Macrolídeos/química , Macrolídeos/farmacologia , Macrolídeos/isolamento & purificação , Macrolídeos/metabolismo , Proliferação de Células/efeitos dos fármacos , Compostos de Espiro/química , Compostos de Espiro/farmacologia , Compostos de Espiro/isolamento & purificação , Relação Estrutura-Atividade , Policetídeo Sintases/metabolismo , Policetídeo Sintases/genética , Linhagem Celular Tumoral , Genoma Bacteriano , Família MultigênicaRESUMO
Seven new phenol derivatives, subversins A-E (1-5), subversic acid A (6) and epi-wortmannine G (7); one new natural product, 4-hydroxy-7-methoxyphthalide (8); and five known compounds (9-13) were isolated from the fungus Aspergillus subversicolor CYH-17 collected from the Haima cold seep. The structures and absolute configurations of these compounds were determined via NMR, MS, optical rotation, electronic circular dichroism (ECD) calculation, X-ray diffraction analysis and comparison with the literature. Compounds 2 and 5 were two pairs of enantiomers. All compounds were tested for their α-glucosidase and acetylcholinesterase (AChE) inhibitory activity, antioxidant activity and antibacterial activity, but no obvious activity was observed among these studied compounds.
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Acetilcolinesterase , Aspergillus , Fenol , Fenóis , FungosRESUMO
This study aimed to find a unique method to assess the textural properties of Niangao (glutinous rice cakes), to determine the relationship between the textural properties of rice cakes and the indicators of glutinous rice, and to identify the key indicators that significantly affect the textural properties of Niangao. The study encompassed the analysis of the chemical composition and pasting characteristics of 22 glutinous rice varieties, revealing the substantial impact of variety on lipid content, straight-chain starch content, and pasting performance. Subsequently, the textural features of the resulting Niangao were subjected to principal component analysis (PCA) to derive a mathematical method for evaluating their textural attributes, with the obtained scores employed in hierarchical cluster analysis (HCA) to identify 12 key textural characteristics. Further analysis using stepwise linear regression (SLR) demonstrated that the regression model incorporating final and peak viscosities of the glutinous rice significantly predicted the composite score of the Niangao's textural properties. This highlights the importance of final and peak viscosities as key indicators for assessing the textural quality of Niangao.
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Frozen staple food, attributed to its favorable taste and convenience, has a promising development potential in the future. Frequent freezing and thawing, however, will affect its quality. This study simulated several freeze-thaw cycles (FTC) that may occur during the cold chain process of frozen oatmeal cooked noodles (FOCN) production to consumption. The quality changes and their mechanisms were elucidated using methods such as differential scanning calorimetry (DSC), low-field nuclear magnetic resonance (LF-NMR), Fourier-transform infrared spectroscopy (FTIR), confocal laser scanning microscopy (CLSM), texture analysis, and sensory evaluation. The freezable water content of the FOCN decreased because of the FTC treatment, and the relative content of total water in FOCN also decreased accordingly. The increase in ß-Turn after FTC induced disorder in the secondary structure of proteins, causing the protein microstructure to become loose and discontinuous, which in turn reduced the water-holding capacity of FOCN. Additionally, FTC reduced the chewiness and sensory score of FOCN. This research will contribute a theoretical foundation for optimizing the cold chain process.
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Brown rice, as a kind of whole-grain food, has attracted significant attention due to its health benefits. This paper aimed to investigate the effect of rice bran content and retrograded time on the physicochemical properties and culinary qualities of brown rice noodles (BRNs). The results indicated that the addition of rice bran altered the pasting properties, gel properties, and texture of the brown rice flours (BRFs). The optimal cooking time and water absorption of BRNs were reduced after the incorporation of rice bran to 14.9% and 41.9%, respectively, while the breaking rate increased from 2.2% to 23.3%. The color of BRNs became darker and yellower, and the overall acceptability by the consumer decreased. The addition of rice bran also led to a decrease in hardness, chewiness and crystallinity. The binding water inside the BRNs decreased, while the free water increased, resulting in a looser structure. This study revealed that the retrograded time of the BRNs also affected its quality. When the retrograded time was 7 h, the cooked BRNs had a lower breaking rate, good hardness, cohesiveness, chewiness, and better overall acceptability by consumers. The structure was compact, the internal binding water content of BRN was higher, and the free water content was lower. This study provides insights into developing nutritionally healthy, high-quality novel rice flour products, and offers a theoretical basis for the industrial production of BRNs.
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One novel diketopiperazine derivative 8R-methoxy-9R-hydroxyl-fumitremorgin C (1), together with twelve known compounds, was separated from the fungus Aspergillus fumigatus CYH-5 collected from Haima cold seep. The structures of the compounds were identified by NMR, MS, optical rotation, hydrolysis reaction and comparing with literatures. Among them, compounds 10 and 11 exhibited inhibitory effect against bacteria. Compound 11 showed inhibitory activity on α-glucosidase and compound 8 displayed acetylcholinesterase (AchE) inhibitory activity.
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Background: Quorum sensing is bacteria's ability to communicate and regulate their behavior based on population density. Anti-quorum sensing agents (anti-QSA) is promising strategy to treat resistant infections, as well as reduce selective pressure that leads to antibiotic resistance of clinically relevant pathogens. This study analyzes the output, hotspots, and trends of research in the field of anti-QSA against clinically relevant pathogens. Methods: The literature on anti-QSA from the Web of Science Core Collection database was retrieved and analyzed. Tools such as CiteSpace and Alluvial Generator were used to visualize and interpret the data. Results: From 1998 to 2023, the number of publications related to anti-QAS research increased rapidly, with a total of 1,743 articles and reviews published in 558 journals. The United States was the largest contributor and the most influential country, with an H-index of 88, higher than other countries. Williams was the most productive author, and Hoiby N was the most cited author. Frontiers in Microbiology was the most prolific and the most cited journal. Burst detection indicated that the main frontier disciplines shifted from MICROBIOLOGY, CLINICAL, MOLECULAR BIOLOGY, and other biomedicine-related fields to FOOD, MATERIALS, NATURAL PRODUCTS, and MULTIDISCIPLINARY. In the whole research history, the strongest burst keyword was cystic-fibrosis patients, and the strongest burst reference was Lee and Zhang (2015). In the latest period (burst until 2023), the strongest burst keyword was silver nanoparticle, and the strongest burst reference was Whiteley et al. (2017). The co-citation network revealed that the most important interest and research direction was anti-biofilm/anti-virulence drug development, and timeline analysis suggested that this direction is also the most active. The key concepts alluvial flow visualization revealed seven terms with the longest time span and lasting until now, namely Escherichia coli, virulence, Pseudomonas aeruginosa, virulence factor, bacterial biofilm, gene expression, quorum sensing. Comprehensive analysis shows that nanomaterials, marine natural products, and artificial intelligence (AI) may become hotspots in the future. Conclusion: This bibliometric study reveals the current status and trends of anti-QSA research and may assist researchers in identifying hot topics and exploring new research directions.
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Utilizing natural hypoglycemic ingredients in staple foods is a safe and effective way to improve diabetes. High Tartary buckwheat noodles have garnered research interest due to their hypoglycemic properties. However, increasing the Tartary buckwheat content poses challenges in noodle processing and affects their edible quality. Effective resting is a critical link to improve the processing performance of noodle and edible quality of noodle. Therefore, research was conducted on ultrasound assisted resting of Tartary buckwheat dough (TBD) to explore its feasibility and mechanism in improving the quality of Tartary buckwheat noodle. The results indicated that ultrasound treatment effectively promoted the migration of weakly-bound water towards strongly-bound water, thereby enhancing the gluten protein network structure and increasing the α-helix and ß-sheet contents significantly (p < 0.05). Furthermore, Texture analysis indicated decreased hardness and adhesion, and increased elasticity and stretching distance in the final noodles. Ultrasound-assisted maturation pre-treatment shortens TBD's dough's resting time and improves noodle quality, according to this study.
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Fagopyrum , Fagopyrum/química , Ultrassom , Glutens/metabolismo , Água , HipoglicemiantesRESUMO
The anti-aging effects of two anionic polysaccharides AG (sodium alginate)/SSPS (soluble soybean polysaccharide) and WS (wheat starch) were evaluated, and their different mechanisms were explored. The rheological properties, gelatinization properties and aging properties were characterized. The addition of AG and SSPS changed the gelatinization parameters of WS, decreased the peak viscosity, breakdown viscosity and setback viscosity, and enhanced the fluidity of the gel system. Additionally, the starch molecular orderliness experiment showed that the relative crystallinity of starch gels decreased with the increase in AG and SSPS concentrations, indicating that the rearrangement of amylopectin was disturbed, which inhibited the cross-linking of starch molecules. The water state analysis showed that the hydrophilicity of AG and SSPS and their interactions with starch molecules influenced the relaxation behavior of water protons in the gel system in a concentration-dependent manner. In conclusion, the addition of AG and SSPS could significantly inhibit the aging of WS gels, probably due to the competition effect of AG and SSPS on water and the interaction with starch molecules. The present study results would provide new theoretical insights into WS-based food research.
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Amido , Triticum , Amido/química , Triticum/química , Polissacarídeos/farmacologia , Viscosidade , Géis/química , ÁguaRESUMO
In the present work, a dual-modified waxy rice starch (OOWRS) fabricated with OSA and ozone was successfully used to stabilize the O/W Pickering emulsion. The molecular structure, surface properties, and underlying stabilizing mechanism were systematically investigated. The results showed that oxidation occurring on the surface of OSA-modified waxy rice starch (OSAWRS) resulted in the presence of indentations and cracks. The relative crystallinity of starch was generally decreased with increasing degree of oxidation. Due to the introduction of carbonyl and the variation in surface structure, the hydrophobicity and acidity of OSAWRS were significantly enhanced after the ozone treatment. Remarkably, OOWRS stabilized Pickering emulsion exhibited a feature of typical O/W emulsion, and the 0.5 h and 1 h OOWRS emulsion exhibited a more uniform droplet size as well as a higher surface potential. We also noted that a weak-gel network was formed within the OOWRS emulsion system as the hydrophilic starch chains played a bridging role. Two reasons for the improved stability of the emulsion were the special gel structure and the enhanced electrical repulsion among the droplets. This research provides that ozone-conjugated OSA modification is a promising strategy for improving the emulsion ability of starch-based Pickering emulsions.
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Oryza , Emulsões/química , Oryza/química , Anidridos Succínicos/química , Amilopectina , Amido/química , Propriedades de Superfície , Tamanho da PartículaRESUMO
Modification of organic molecules with fluorine functionalities offers a critical approach to develop new pharmaceuticals. Here, we report a multienzyme strategy for biocatalytic fluoroalkylation using S-adenosyl-l-methionine (SAM)-dependent methyltransferases (MTs) and fluorinated SAM cofactors prepared from ATP and fluorinated l-methionine analogues by an engineered human methionine adenosyltransferase hMAT2AI322A. This work introduces the first example of biocatalytic 3,3-difluoroallylation. Importantly, this strategy can be applied to late-stage site-selective fluoroalkylation of complex molecule vancomycin with conversions up to 99%.
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Metionina , S-Adenosilmetionina , Humanos , Metionina/metabolismo , S-Adenosilmetionina/metabolismo , Metiltransferases/metabolismo , Racemetionina , BiocatáliseRESUMO
Starch staling greatly reduces the cereal products quality, and the staling retardation becomes a focus in current research. The effect of wheat oligopeptide (WOP) on anti-staling properties of wheat starch (WS) was studied. Rheology property indicated that WOP reduced WS viscosity, showing more liquid-like behavior. WOP improved the water holding capacity, inhibited swelling power, and reduced the hardness of WS gels, which decreased from 1200 gf to 800 gf compared with the control after 30 days storage. Meanwhile, the water migration of WS gels were also reduced with WOP incorporation. The relative crystallinity of WS gel with 1% WOP was reduced by 13.3%, and the pore size and the microstructure of gels was improved with WOP. Besides, the short-range order degree reached the lowest value with 1% WOP. In conclusion, this study explained the interaction between WOP and WS, which was beneficial to the application of WOP in WS-based food.