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1.
Artigo em Inglês | MEDLINE | ID: mdl-39102145

RESUMO

Submarine groundwater drainage (SGD) changes the elemental composition of the neighboring coastal ocean and impacts the biogeochemical cycles. To examine the seasonal and spatial variability in dissolved organic carbon (DOC) and labile organic compound biochemical compounds like dissolved carbohydrates (TDCHO), dissolved proteins (TDPRO), and dissolved free amino acid (TDFAA) concentrations during the dry and wet periods, groundwater samples were taken at 90 locations (180 samples) along the Indian coast. The mean DOC contents in Indian coastal groundwaters were more significant than the global mean values. DOC, TDCHO, TDPRO, and TDFAA concentrations are higher during wet than dry periods. The DOC and labile organic compound showed a substantial positive association with soil organic carbon, and respective labile compounds in soil, population, and land usage and poor relation with woodland territories, implying that soil organic compounds leaching is a source of DOC and other labile organic compounds into the groundwater. DOC and other labile compounds concentrations were linearly associated with population density, land usage, and sewage production, demonstrating that anthropogenic activities tightly regulate the formation of DOC in groundwater. During the wet and dry periods, total labile organic compounds (TDCHO, TDFAA, and TDPRO) constituted 21% and 10.5% of DOC, respectively. Compared to the wet time, more aromatic compounds accumulated during the dry season but were less bioavailable. SGD DOC flux contributed 2-7% of riverine DOC flux to the coastal ocean. The SGD flux from the Indian subcontinent to the nearby northern Indian Ocean accounts for approximately 2% of the worldwide SGD flux. The effect of DOC flux via SGD on coastal bacterial activity, the plankton food web, and the oxygen minimum zone must be studied.

2.
Int J Biol Macromol ; 277(Pt 3): 134394, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39094858

RESUMO

Microcrystalline cellulose (MCC) is a crucial component in various industries, including pharmaceuticals, culinary, and cosmetics. The growing demand for MCC has spurred research into extraction methods. This study focused on extracting MCC from Ficus benghalensis using acid hydrolysis to convert the alpha-cellulose content of its leaves into MCC. The solvent used in this process was recyclable for further use. The extracted MCC was characterized by its physicochemical properties, including density, yield percentage, and structural characteristics. The yield was approximately 39.68 %, and the density was low at 1.518 g/cm3, making it suitable for filler applications. Fourier transform spectroscopy and UV-visible analysis identified functional groups of cellulose. X-ray diffraction analysis revealed a crystallite size of 1.560 nm and a crystallinity index of 66.43 %, indicating suitability for related applications. ImageJ determined a mean particle size of 36.545 µm, while scanning electron microscopy showed distinct surface orientations. Atomic force microscopy revealed surface roughness, root mean square, ten-point average roughness, skewness, and kurtosis. Elemental analysis indicated high concentrations of carbon (20.1 %) and oxygen (34 %). Based on these physicochemical features, the extracted MCC could be a valuable source for applications such as filler in reinforcement technology and coating material in pharmaceutical products.

3.
Front Immunol ; 15: 1436039, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39148735

RESUMO

Klebsiella pneumoniae is an opportunistic bacterium that frequently colonizes the nasopharynx and gastrointestinal tract and can also cause severe infections when invading other tissues, particularly in immunocompromised individuals. Moreover, K. pneumoniae variants exhibiting a hypermucoviscous (HMV) phenotype are usually associated with hypervirulent strains that can produce invasive infections even in immunocompetent individuals. Major carbohydrate structures displayed on the K. pneumoniae surface are the polysaccharide capsule and the lipopolysaccharide, which presents an O-polysaccharide chain in its outermost part. Various capsular and O-chain structures have been described. Of note, production of a thick capsule is frequently observed in HMV variants. Here we examined the surface sugar epitopes of a collection of HMV and non-HMV K. pneumoniae clinical isolates and their recognition by several Siglecs and galectins, two lectin families of the innate immune system, using bacteria microarrays as main tool. No significant differences among isolates in sialic acid content or recognition by Siglecs were observed. In contrast, analysis of the binding of model lectins with diverse carbohydrate-binding specificities revealed striking differences in the recognition by galactose- and mannose-specific lectins, which correlated with the binding or lack of binding of galectins and pointed to the O-chain as the plausible ligand. Fluorescence microscopy and microarray analyses of galectin-9 binding to entire cells and outer membranes of two representative HMV isolates supported the bacteria microarray results. In addition, Western blot analysis of the binding of galectin-9 to outer membranes unveiled protein bands recognized by this galectin, and fingerprint analysis of these bands identified several proteins containing potential O-glycosylation sites, thus broadening the spectrum of possible galectin ligands on the K. pneumoniae surface. Moreover, Siglecs and galectins apparently target different structures on K. pneumoniae surfaces, thereby behaving as non-redundant complementary tools of the innate immune system.


Assuntos
Galectinas , Imunidade Inata , Infecções por Klebsiella , Klebsiella pneumoniae , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , Klebsiella pneumoniae/imunologia , Klebsiella pneumoniae/metabolismo , Humanos , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/metabolismo , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico/imunologia , Galectinas/metabolismo , Galectinas/imunologia , Infecções por Klebsiella/imunologia , Infecções por Klebsiella/microbiologia , Cápsulas Bacterianas/imunologia , Cápsulas Bacterianas/metabolismo , Lectinas/metabolismo , Lectinas/imunologia , Ligação Proteica
4.
Angew Chem Int Ed Engl ; : e202409530, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39152096

RESUMO

Going beyond currently reported two electron transformations that formed the core backdrop of asymmetric catalytic site-selective carbohydrate polyol functionalizations, we herein report a seminal demonstration of an enantioconvergent copper catalyzed site-selective etherification of minimally protected saccharides through a single-electron radical pathway. Further, this strategy paves a rare strategy, through which a carboxamide scaffold that is present in some glycomimetics of pharmacological relevance, can be selectively introduced. In light of the burgeoning interest in chiral radical catalysis, and the virtual absence of such stereocontrol broadly in carbohydrate synthesis, our strategy showcased the unknown capability of chiral radical copper catalysis as a contemporary tool to address the formidable site-selectivity challenge on a remarkable palette of naturally occurring saccharides. When reducing sugars were employed, a further dynamic kinetic resolution type glycosylation can be activated by the catalytic system to selectively generate the challenging ß-O-glycosides.

5.
J Plant Physiol ; 303: 154325, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39142140

RESUMO

Potassium (K) deficiency occurs commonly in crop plants. Optimal K nutrition is particularly important when plants are exposed to stress conditions (especially drought and heat) because a cellular demand for K increases. Low K in plant tissues is known to aggravate the effects of drought stress by impairing the osmoregulation process and the photosynthetic carbon metabolism. However, despite numerous publications about the role of K in enhancing tolerance to drought stress in crop plants, our understanding of the major mechanisms underlying the stress-mitigating effects of K is still limited. This paper summarizes and appraises the current knowledge on the major protective effects of K under drought stress, and then proposes a new K-related drought stress-mitigating mechanism, whereby optimal K nutrition may promote partitioning of carbohydrates in stem tissues and subsequent mobilization of these carbohydrates into developing grain under drought stress. The importance of stem reserves of carbohydrates is based on limited photosynthetic capacity during the grain-filling period under drought conditions due to premature leaf senescence as well as due to impaired assimilate transport from leaves to the developing grains. Plants with a high capacity to store large amounts of soluble carbohydrates in stems before anthesis and mobilize them into grain post-anthesis have a high potential to yield well in dry and hot environments. In practice, particular attention needs to be paid to the K nutritional status of plants grown with limited water supply, especially during grain filling. Because K is the mineral nutrient deposited mainly in stem, a special consideration should be given to stems of crop plants in research dealing with the effects of K on yield formation and stress mitigation.

6.
Plants (Basel) ; 13(15)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39124167

RESUMO

In a tropical savanna climate like Thailand, cassava can be planted all year round and harvested at 8 to 12 months after planting (MAP). However, it is not clear how water limitation during the dry season without rain affects carbon assimilation, partitioning, and yield. In this field investigation, six cassava genotypes were planted in the rainy season (August 2021) under continuous irrigation (control) or subjected to drought for 60 days from 3MAP to 5MAP during the dry season (November 2021 to January 2022) with no irrigation and rainfall. After that, the plants were rewatered and continued growing until harvest at 12MAP. After 60 days of stress, there were significant reductions in the mean net photosynthesis rate (Pn), petiole, and root dry weight (DW), and slight reductions in leaf, stem, and tuber DW. The mean starch concentrations were reduced by 42% and 16% in leaves and tubers, respectively, but increased by 12% in stems. At 6MAP after 30 days of rewatering, Pn fully recovered, and stem starch was remobilized resulting in a dramatic increase in the DW of all the organs. Although the mean tuber DW of the drought plants at 6MAP was significantly lower than that of the control, it was significantly higher at 12MAP. Moreover, the mean tuber starch concentration at 12MAP of the drought plants (18.81%) was also significantly higher than that of the controls (16.46%). In the drought treatment, the high-yielding varieties, RY9, RY72, KU50, and CMR38-125-77 were similarly productive in terms of tuber DW and starch concentration while the breeding line CM523-7 produced the lowest tuber biomass and significantly lower starch content. Therefore, for cassava planted in the rainy season in the tropical savanna climate, the exposure to drought during the early growth stage was more beneficial than the continuous irrigation.

7.
Polymers (Basel) ; 16(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39125124

RESUMO

Polymer self-assembly can prepare various shapes and sizes of pores, making it widely used. The complexity and diversity of biomolecules make them a unique class of building blocks for precise assembly. They are particularly suitable for the new generation of biomaterials integrated with life systems as they possess inherent characteristics such as accurate identification, self-organization, and adaptability. Therefore, many excellent methods developed have led to various practical results. At the same time, the development of advanced science and technology has also expanded the application scope of self-assembly of synthetic polymers. By utilizing this technology, materials with unique shapes and properties can be prepared and applied in the field of tissue engineering. Nanomaterials with transparent and conductive properties can be prepared and applied in fields such as electronic displays and smart glass. Multi-dimensional, controllable, and multi-level self-assembly between nanostructures has been achieved through quantitative control of polymer dosage and combination, chemical modification, and composite methods. Here, we list the classic applications of natural- and artificially synthesized polymer self-assembly in the fields of biomedicine and materials, introduce the cutting-edge technologies involved in these applications, and discuss in-depth the advantages, disadvantages, and future development directions of each type of polymer self-assembly.

8.
Nutrients ; 16(15)2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39125337

RESUMO

The ketogenic diet is used worldwide to treat various diseases, especially drug-resistant epilepsies. Medium-chain triglycerides or medium-chain fatty acids, primarily the major ketogenic compound caprylic acid (C8; C8:0), can significantly support ketogenesis. This review examines the effects of concurrent carbohydrate intake on C8-induced ketogenesis. A systematic literature search (PubMed and Web of Science) with subsequent data extraction was performed according to PRISMA guidelines and the Cochrane Handbook. Studies investigating the metabolic response to C8-containing MCT interventions with carbohydrate intake were included. The studies did not include a ketogenic diet. Three intervention groups were created. The quality of the studies was assessed using the RoB II tool, and the meta-analysis was performed using the Cochrane RevMan software. A total of 7 trials, including 4 RCTs, met the inclusion criteria. Ketone production was lower when C8 was combined with carbohydrates compared to MCT intake alone. The lower C8 dose group (11 g) did not show a significantly lower ketogenic effect than the higher dose group (19 g). Forest plot analysis showed heterogeneous data. The data suggest a non-linear relationship between C8, carbohydrate intake and ketone production. Further studies are needed to investigate the influence of different carbohydrates on C8-induced ketogenesis. Limitations include heterogeneous intervention conditions, such as different types of dispersions, caffeine intake, limited number of studies and variability in study design.


Assuntos
Caprilatos , Dieta Cetogênica , Carboidratos da Dieta , Humanos , Caprilatos/administração & dosagem , Dieta Cetogênica/métodos , Carboidratos da Dieta/administração & dosagem , Cetonas/administração & dosagem
9.
Food Res Int ; 192: 114810, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39147505

RESUMO

Using green techniques to convert native starches into nanoparticles is an interesting approach to producing stabilizers for Pickering emulsions, aiming at highly stable emulsions in clean label products. Nanoprecipitation was used to prepare the Pickering starch nanoparticles, while ultrasound technique has been used to modulate the size of these nanoparticles at the same time as the emulsion was developed. Thus, the main objective of this study was to evaluate the stabilizing effect of cassava starch nanoparticles (SNP) produced by the nanoprecipitation technique combined with ultrasound treatment carried out in the presence of water and oil (more hydrophobic physicochemical environment), different from previous studies that carry out the mechanical treatment only in the presence of water. The results showed that the increased ultrasound energy input could reduce particle size (117.58 to 55.75 nm) and polydispersity (0.958 to 0.547) in aqueous dispersions. Subsequently, Pickering emulsions stabilized by SNPs showed that increasing emulsification (ultrasonication) time led to smaller droplet sizes and monomodal size distribution. Despite flocculation, long-term ultrasonication (6 and 9 min) caused little variation in the droplet size after 7 days of storage. The cavitation effects favored the interaction between oil droplets through weak attraction forces and particle sharing, favoring the Pickering stabilization against droplet coalescence. Our results show the potential to use only physical modifications to obtain nanoparticles that can produce coalescence-stable emulsions that are environmentally friendly.


Assuntos
Emulsões , Manihot , Nanopartículas , Tamanho da Partícula , Amido , Manihot/química , Amido/química , Emulsões/química , Nanopartículas/química , Água/química , Sonicação/métodos , Floculação
10.
Food Res Int ; 192: 114840, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39147525

RESUMO

Bifidobacterium pseudocatenulatum is a prevalent gut microbe in humans of all ages and plays a crucial role in host health. However, its adaptive evolutionary characteristics remain poorly understood. This study analyzed the genome of 247 B. pseudocatenulatum isolates from Chinese, Vietnamese, Japanese and other region populations using population genomics and functional genomics. Our findings revealed high genetic heterogeneity and regional clustering within B. pseudocatenulatum isolates. Significant differences were observed in genome characteristics, phylogeny, and functional genes. Specifically, Chinese and Vietnamese isolates exhibited a higher abundance of genes involved in the metabolism of plant-derived carbohydrates (GH13, GH43, and GH5 enzyme families), aligning with the predominantly vegetable-, wheat- and fruit-based diets of these populations. Additionally, we found widespread transmission of antibiotic resistance genes (tetO and tetW) through mobile genetic elements, such as genomic islands (GIs), resulting in substantial intra-regional differences. Our findings highlight distinct adaptive evolution in B. pseudocatenulatum driven by gene specialization, possibly in response to regional variations in diet and lifestyle. This study sheds light on bifidobacteria colonization mechanisms in the host gut. IMPORTANCE: Gut microbiota, as a key link in the gut-brain axis, helps to maintain the health of the organism, among which, Bifidobacterium pseudocatenulatum (B. pseudocatenulatum) is an important constituent member of the gut microbiota, which plays an important role in maintaining the balance of gut microbiota. The probiotic properties of B. pseudocatenulatum have been widely elaborated, and in order to excavate its evolutionary features at the genomic level, here we focused on the genetic background and evolutionary mechanism of the B. pseudocatenulatum genomes isolated from the intestinal tracts of different populations. Ultimately, based on the phylogenetic tree, we found that B. pseudocatenulatum has high genetic diversity and regional clustering phenomenon, in which plant-derived carbohydrate metabolism genes (GH13, GH43, GH5) showed significant regional differences, and this genetic differentiation drove the adaptive evolution, which likely shaped by diet and lifestyle.


Assuntos
Bifidobacterium pseudocatenulatum , Microbioma Gastrointestinal , Genoma Bacteriano , Filogenia , Microbioma Gastrointestinal/genética , Humanos , Bifidobacterium pseudocatenulatum/genética , Bifidobacterium pseudocatenulatum/metabolismo , Variação Genética , Genômica , Dieta
11.
Food Res Int ; 192: 114844, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39147527

RESUMO

Non-digestible oligosaccharides (OS) and allulose have beneficial health properties and could reduce the amount of added sugar in baked goods. In this study allulose and various OS [fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), lactosucrose (LOS), isomalto-oligosaccharides (IMO), Promitor 70R (P70R), and xylo-oligosaccharides (XOS)] were added to a wire-cut cookie formulation at concentrations determined to have similar effects on the gelatinization temperature (Tgel) of starch relative to sucrose. Different baking performance attributes of the doughs and cookies were assessed, including: appearance, spread, color, texture, and % moisture loss after baking. The results were correlated to: OS solution and solid properties and OS effects on starch thermal events (gelatinization, pasting, and retrogradation). The Tgel-matching formulation protocol was effective in producing reduced-sugar cookies which had similar appearance, color, and spread attributes compared to the sucrose control; however, cookie texture significantly varied. Cookies containing allulose were the least similar to the control, having darker color, reduced spread, and softer cake-like texture. The only OS cookies that matched the texture of the sucrose control contained LOS, while P70R cookies were the hardest. Cookie texture correlated strongly with the % total moisture loss after baking (r = -0.8763) and was best explained by OS solution viscosity: more viscous OS solutions limited moisture release and resulted in harder cookies. The Tgel of starch also correlated with OS solution viscosity (r = 0.7861) and should be accounted for in reduced sugar applications. The OS recommended as sucrose replacers in cookies based on principal component analysis groupings were: XOS > IMO > LOS > and GOS.


Assuntos
Oligossacarídeos , Oligossacarídeos/química , Culinária/métodos , Sacarose/química , Amido/química , Cor , Água/química , Frutose/química , Manipulação de Alimentos/métodos , Viscosidade , Temperatura
12.
New Phytol ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39149848

RESUMO

Stomatal closure during drought inhibits carbon uptake and may reduce a tree's defensive capacity. Limited carbon availability during drought may increase a tree's mortality risk, particularly if drought constrains trees' capacity to rapidly produce defenses during biotic attack. We parameterized a new model of conifer defense using physiological data on carbon reserves and chemical defenses before and after a simulated bark beetle attack in mature Pinus edulis under experimental drought. Attack was simulated using inoculations with a consistent bluestain fungus (Ophiostoma sp.) of Ips confusus, the main bark beetle colonizing this tree, to induce a defensive response. Trees with more carbon reserves produced more defenses but measured phloem carbon reserves only accounted for c. 23% of the induced defensive response. Our model predicted universal mortality if local reserves alone supported defense production, suggesting substantial remobilization and transport of stored resin or carbon reserves to the inoculation site. Our results show that de novo terpene synthesis represents only a fraction of the total measured phloem terpenes in P. edulis following fungal inoculation. Without direct attribution of phloem terpene concentrations to available carbon, many studies may be overestimating the scale and importance of de novo terpene synthesis in a tree's induced defense response.

13.
Ann Bot ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39086357

RESUMO

BACKGROUND AND AIMS: Leaf elongation is vital for Poaceae species' productivity, influenced by atmospheric CO2 concentration ([CO2]) and climate-induced water availability changes. Although [CO2] mitigates the effects of drought on reducing transpiration per unit leaf area, it also increases total leaf area and water use. These complex interactions associated with leaf growth pose challenges in anticipating climate change effects. This study aims to assess [CO2] effects on leaf growth response to drought in perennial ryegrass (Lolium perenne), tall fescue (Festuca arundinacea) and wheat (Triticum aestivum). METHODS: Plants were cultivated in growth chambers with [CO2] at 200 or 800 ppm. At leaf six to seven unfolding, half of the plants were subjected to severe drought treatment. Leaf elongation rate (LER) was measured daily, whereas plant transpiration was continuously recorded gravimetrically. Additionally, water-soluble carbohydrate (WSC) content along with water and osmotic potentials in the leaf growing zone were measured at drought onset, mid-drought and leaf growth cessation. KEY RESULTS: Elevated [CO2] mitigated drought impacts on LER and delayed growth cessation across species. A positive correlation between LER and soil relative water content (SRWC) was observed. At the same SRWC, perennial grasses exhibited a higher LER with elevated [CO2], likely due to enhanced stomatal regulation. Despite stomatal closure and WSC accumulation, CO2 did not influence nighttime water potential or osmotic potential. The marked increase in leaf area across species resulted in similar (wheat and tall fescue) or higher (ryegrass) total water use by the experiment's end, under both watered and unwatered conditions. CONCLUSIONS: In conclusion, elevated [CO2] mitigates the adverse effects of drought on leaf elongation in three Poaceae species, due to its impact on plant transpiration. Overall, these findings provide valuable insights into CO2 and drought interactions that may help anticipate plant responses to climate change.

14.
Food Chem ; 460(Pt 2): 140730, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39106810

RESUMO

This study aimed to elucidate the effects of storage temperature on various fruit quality attributes, physiological disorders, and associated metabolites in the 0.5, 3, or 10 °C stored hardy kiwifruit. Peel pitting, which was highest in the 0.5 °C stored fruit, was identified as a chilling injury symptom of hardy kiwifruit. Proline and branched-chain amino acid contents showed higher values at 0.5 °C stored fruit as chilling responses. On the other hand, fruit shriveling and decay were highest in the 10 °C after 5 weeks of storage. The 10 °C storage induced fruit ripening during 3 weeks, but fruit shriveling and decay were severe after 5 weeks of storage. Therefore, storing the 'Autumn Sense' hardy kiwifruit at proper temperatures would be more beneficial, as it alters targeted metabolites and helps reduce the incidence of physiological disorders during cold storage.

15.
Front Plant Sci ; 15: 1436152, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39091320

RESUMO

Introduction: Salinity and droughts are severe abiotic stress factors that limit plant growth and development. However, the differences and similarities of non-structural carbohydrates (NSCs) responses patterns of trees under the two stress conditions remain unclear. Methods: We determined and compared the growth, physiology, and NSCs response patterns and tested the relationships between growth and NSCs concentrations (or pool size) of Eucommia ulmoides seedlings planted in field under drought and salt stress with different intensities and durations. Results and discussion: We found that drought and salt stress can inhibit the growth of E. ulmoides, and E. ulmoides tended to enhance its stress resistance by increasing proline concentration and leaf thickness or density but decreasing investment in belowground biomass in short-term stress. During short-term drought and salt stress, the aboveground organs showed different NSCs response characteristics, while belowground organs showed similar change characteristics: the starch (ST) and NSCs concentrations in the coarse roots decreased, while the ST and soluble sugar (SS) concentrations in the fine roots increased to enhance stress resistance and maintain water absorption function. As salt and drought stress prolonged, the belowground organs represented different NSCs response patterns: the concentrations of ST and SS in fine roots decreased as salt stress prolonged; while ST in fine roots could still be converted into SS to maintain water absorption as drought prolonged, resulting in an increase of SS and a decrease of ST. Significant positive relationships were found between growth and the SS and total NSCs concentrations in leaves and branches, however, no significant correlations were found between growth and below-ground organs. Moreover, relationships between growth and NSCs pool size across organs could be contrast. Conclusion: Our results provide important insights into the mechanisms of carbon balance and carbon starvation and the relationship between tree growth and carbon storage under stress, which were of great significance in guiding for the management of artificial forest ecosystem under the context of global change.

16.
Mar Pollut Bull ; 206: 116798, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39116752

RESUMO

The sea surface microlayer (SML), particularly in monsoon-influenced regions, remains largely unexplored. This study aims to determine the concentrations, enrichment, and factors controlling the enrichment processes of surface-active substances (SASs), which include surfactants, dissolved monosaccharides (MCHOs), polysaccharides (PCHOs), total dissolved carbohydrates (TDCHOs), and transparent exopolymer particles (TEPs) around the coastal area of Malaysian Peninsula. The SML samples and underlying water (ULW) from a depth of 1 m were collected during the southwest (August and September 2023) and northeast (November 2023) monsoons. Surfactants, TEPs, and dissolved carbohydrates were measured spectrometrically using methylene blue, the Alcian blue assay, and 2,4,6-Tri(2-pyridyl)-s-triazine (TPTZ), respectively. The results showed that stations influenced by anthropogenic activities were generally enriched with surfactants (Enrichment factor, EF = 1.40 ± 0.91) and carbohydrate species (TDCHOs = 1.38 ± 0.28, MCHOs = 1.54 ± 0.57, PCHOs = 1.85 ± 1.43). However, TEP enrichment was not observed in our study (EF = 0.68 ± 0.24). The SASs in the SML were correlated with their underlying concentrations, implying that transport from underlying water could be a major source of substances in the SML. High carbohydrate concentrations and enrichment were found during the northeast monsoon, implying that rain and runoff water affect concentrations in the SML. Besides, the enrichment of SASs persists at moderate wind speeds and is depleted at high wind speeds.

17.
Front Plant Sci ; 15: 1388881, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39119506

RESUMO

Introduction: Wheat grain filling processes under post-anthesis stress scenarios depend mainly on stem traits and remobilization of stem water-soluble carbohydrates (WSC). Methods: A diverse panel of advanced semi-dwarf spring wheat lines, representing a natural variation in stem traits (WSC content, stem diameter, peduncle length, and stem wall width), was used to identify specific traits that reliably reflect the relationship between WSC and grain yield. The panel was phenotyped under various environmental conditions: well-watered, water-limited, and heat stress in Mexico, and terminal-drought in Israel. Results: Environmental stresses reduced grain yield (from 626 g m-2 under well-watered to 213 g m-2 under heat), lower internode diameter, and peduncle length. However, stem-WSC generally peaked 3-4 weeks after heading under all environmental conditions except heat (where it peaked earlier) and expressed the highest values under water-limited and terminal-drought environments. Increased investment in internode diameter and peduncle length was associated with a higher accumulation of stem WSC, which showed a positive association with yield and kernel weight. Across all environments, there were no apparent trade-offs between increased crop investment in internode diameter, peduncle length, and grain yield. Discussion: Our results showed that selecting for genotypes with higher resource investment in stem structural biomass, WSC accumulation, and remobilization could be a valuable strategy to ameliorate grain size reduction under stress without compromising grain yield potential. Furthermore, easy-to-measure proxies for WSC (stem diameter at specific internodes and length of the last internode, i.e., the peduncle) could significantly increase throughput, potentially at the breeding scale.

18.
Food Chem X ; 23: 101590, 2024 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-39036475

RESUMO

Food processing transforms raw materials into different food forms using physical or chemical techniques. Recently, carbohydrates have gained attention for their diverse biological activities like antioxidant, anticancer, and antimutagenic effects. Selecting suitable processing methods is crucial to preserve the beneficial properties of carbohydrates. This review discusses the impact of non-thermal and thermal processing on the physicochemical and biological traits of carbohydrates, highlighting the need for understanding the mechanisms underlying these changes. Future research will focus on enhancing and safeguarding the biological and functional aspects of carbohydrates through improved processing techniques. The goal is to optimize methods that maintain the beneficial properties of carbohydrates, maximizing their health benefits for consumers.

19.
Angew Chem Int Ed Engl ; : e202410681, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39041709

RESUMO

Flexible acquisition of substrates from nutrient pools is critical for microbes to prevail in competitive environments. To acquire glucose from diverse glycoside and disaccharide substrates, many free-living and symbiotic bacteria have developed, alongside hydrolysis, a non-hydrolytic pathway comprised of four biochemical steps and conferred from a single glycoside utilization gene locus (GUL). Mechanistically, this pathway integrates within the framework of oxidation and reduction at the glucosyl/glucose C3, the eliminative cleavage of the glycosidic bond and the addition of water in two consecutive lyase-catalyzed reactions. Here, based on study of enzymes from the phytopathogen Agrobacterium tumefaciens, we reveal a conserved Mn2+ metallocenter active site in both lyases and identify the structural requirements for specific catalysis to elimination of 3-keto-glucosides and water addition to the resulting 2-hydroxy-3-keto-glycal product, yielding 3-keto-glucose. Extending our search of GUL-encoded putative lyases to the human gut commensal Bacteroides thetaiotaomicron, we discover a Ca2+ metallocenter active site in a putative glycoside hydrolase-like protein and demonstrate its catalytic function in the eliminative cleavage of 3-keto-glucosides of opposite (alpha) anomeric configuration as preferred by the A. tumefaciens enzyme (beta). Findings identify a basic set of GUL-encoded lyases for glucoside metabolism and assign physiological significance to GUL genetic diversity in bacteria.

20.
J Int Soc Sports Nutr ; 21(1): 2366427, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38961627

RESUMO

BACKGROUND: The purpose of the review was to evaluate the literature exploring nutritional habits and practices in female soccer players. METHODS: The PRISMA-ScR Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews were followed. Searches of Web of Science, PubMed and Scopus databases were conducted for studies exploring the nutritional habits and practices of female soccer players. RESULTS: A total of 72 studies were included in the scoping review. Studies on female soccer players mainly focused on daily energy expenditure, daily energy and macronutrient intake and hydration status. A negative energy balance was consistent across studies, and the ingestion of CHO appears below the current recommendations. Female soccer players are predominately in negative energy balance, which may indicate that they are at risk of low energy availability. A high use of nutritional supplements is apparent in female soccer, whilst a large proportion of players commence training dehydrated. CONCLUSIONS: The current findings have implications for practitioners relating to the planning, management, monitoring, and implementation of nutritional intake and training and competition schedules.


Assuntos
Suplementos Nutricionais , Metabolismo Energético , Futebol , Futebol/fisiologia , Humanos , Feminino , Ingestão de Energia , Fenômenos Fisiológicos da Nutrição Esportiva , Comportamento Alimentar , Estado de Hidratação do Organismo/fisiologia
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