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1.
Molecules ; 28(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36677822

RESUMO

Carbohydrate analysis can be used as a standard analysis for quality control of industries of plants, foods and pharmaceuticals. Quantitative 1H NMR spectroscopy (qNMR) is an excellent alternative to chromatography-based mixture analysis. However, the application of qNMR in sugar analysis has rarely been reported. In this study, the performance of qNMR in sugar analysis was investigated and compared with the results from HPLC analysis. A head-to-head comparison of qNMR (internal and external standard methods) versus HPLC (PMP pre-column derivatization HPLC, HPLC-RID and HPLC-ELSD) based on quantitative analysis of four carbohydrates (fructose, glucose, sucrose and maltose) in Yiqi Fumai lyophilized injection (YQFM) is presented. Both assays showed similar performance characteristics, including linearity range, accuracy, precision and recovery, and analysis times of less than 30 min/sample. After methodological validation, both qNMR and HPLC have good accuracy, precision and stability. Indeed, the qNMR method is simple, sensitive and rapid in quantifying the four sugars. By analysis of variance (ANOVA) for sugar content with HPLC and qNMR methods, we demonstrated that the two analytical methods had no significant difference and could be used interchangeably for the quantitative analysis of carbohydrates.


Assuntos
Carboidratos , Imageamento por Ressonância Magnética , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética/métodos , Açúcares
2.
BMC Microbiol ; 23(1): 32, 2023 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-36707764

RESUMO

BACKGROUND: Interactions between diet, stress and the gut microbiome are of interest as a means to modulate health and performance. Here, in vitro fermentation was used to explore the effects of a sudden change in diet, 21 days sole sustenance on the Meal, Ready-to-Eat (MRE) U.S. military combat ration, on inter-species competition and functional potential of the human gut microbiota. Human fecal samples collected before and after MRE intervention or consuming a habitual diet (HAB) were introduced to nutrient-rich media supplemented with starch for in vitro fermentation under ascending colon conditions. 16S rRNA amplicon and Whole-metagenome sequencing (WMS) were used to measure community composition and functional potential. Specific statistical analyses were implemented to detect changes in relative abundance from taxa, genes and pathways. RESULTS: Differential changes in relative abundance of 11 taxa, Dorea, Lachnospira, Bacteroides fragilis, Akkermansia muciniphila, Bifidobacterium adolescentis, Betaproteobacteria, Enterobacteriaceae, Bacteroides egerthii, Ruminococcus bromii, Prevotella, and Slackia, and nine Carbohydrate-Active Enzymes, specifically GH13_14, over the 24 h fermentation were observed as a function of the diet intervention and correlated to specific taxa of interest. CONCLUSIONS: These findings suggest that consuming MRE for 21 days acutely effects changes in gut microbiota structure in response to carbohydrate but may induce alterations in metabolic capacity. Additionally, these findings demonstrate the potential of starch as a candidate supplemental strategy to functionally modulate specific gut commensals during stress-induced states.


Assuntos
Microbioma Gastrointestinal , Humanos , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética , Dieta , Fezes/microbiologia , Carboidratos , Amido/metabolismo , Suplementos Nutricionais
3.
Proc Natl Acad Sci U S A ; 120(3): e2212474120, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36626556

RESUMO

Plants respond to oxygen deprivation by activating the expression of a set of hypoxia-responsive genes (HRGs). The master regulator of this process is a small group of transcription factors belonging to group VII of the ethylene response factors (ERF-VIIs). ERF-VIIs are highly unstable under aerobic conditions due to the continuous oxidation of their characteristic Cys residue at the N terminus by plant cysteine oxidases (PCOs). Under hypoxia, PCOs are inactive and the ERF-VIIs activate transcription of the HRGs required for surviving hypoxia. However, if the plant exposed to hypoxia has limited sugar reserves, the activity of ERF-VIIs is severely dampened. This suggests that oxygen sensing by PCO/ERF-VII is fine-tuned by another sensing pathway, related to sugar or energy availability. Here, we show that oxygen sensing by PCO/ERF-VII is controlled by the energy sensor target of rapamycin (TOR). Inhibition of TOR by genetic or pharmacological approaches leads to a much lower induction of HRGs. We show that two serine residues at the C terminus of RAP2.12, a major ERF-VII, are phosphorylated by TOR and are needed for TOR-dependent activation of transcriptional activity of RAP2.12. Our results demonstrate that oxygen and energy sensing converge in plants to ensure an appropriate transcription of genes, which is essential for surviving hypoxia. When carbohydrate metabolism is inefficient in producing ATP because of hypoxia, the lower ATP content reduces TOR activity, thus attenuating the efficiency of induction of HRGs by the ERF-VIIs. This homeostatic control of the hypoxia-response is required for the plant to survive submergence.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Oxigênio , Fosfatidilinositol 3-Quinases , Trifosfato de Adenosina/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Carboidratos , Cisteína Dioxigenase/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Hipóxia , Oxigênio/metabolismo , Açúcares/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo
4.
Nat Ecol Evol ; 7(1): 127-142, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36604549

RESUMO

Dietary fibre impacts the growth dynamics of human gut microbiota, yet we lack a detailed and quantitative understanding of how these nutrients shape microbial interaction networks and responses to perturbations. By building human gut communities coupled with computational modelling, we dissect the effects of fibres that vary in chemical complexity and each of their constituent sugars on community assembly and response to perturbations. We demonstrate that the degree of chemical complexity across different fibres limits microbial growth and the number of species that can utilize these nutrients. The prevalence of negative interspecies interactions is reduced in the presence of fibres compared with their constituent sugars. Carbohydrate chemical complexity enhances the reproducibility of community assembly and resistance of the community to invasion. We demonstrate that maximizing or minimizing carbohydrate competition between resident and invader species enhances resistance to invasion. In sum, the quantitative effects of carbohydrate chemical complexity on microbial interaction networks could be exploited to inform dietary and bacterial interventions to modulate community resistance to perturbations.


Assuntos
Microbioma Gastrointestinal , Humanos , Reprodutibilidade dos Testes , Microbioma Gastrointestinal/fisiologia , Bactérias , Carboidratos , Açúcares
5.
Sci Rep ; 13(1): 284, 2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36609426

RESUMO

The medicinal use of Persea americana in the treatment of some diseases like hypertension, diabetes, is often with dearth of supporting scientific proof. Thus, we evaluated its ethnomedicinal benefits for possible scientific justification. Thirty healthy Wistar rats were randomly grouped in fives. Alloxan was used to induce diabetes in the rats in groups II to VI. The diabetic rats in group II were treated with glibenclamide, while those in group III were not treated. Also, the diabetic rats in groups IV to VI were treated with the ethanol extracts of the stem bark, leaf, and root of P. americana respectively. The parts of P. americana comparatively possess highest amounts of phenols (250.50 ± 0.68-bark), saponin (436.80 ± 3.76-leaf), flavonoid (382.80 ± 0.67-leaf) and tannins (58.34 ± 0.09-root). The extracts exhibited high reducing property (FRAP and total reducing), as well as high ABTS and DPPH free radical scavenging ability. The enzyme (alpha-glycosidase and alpha-amylase) inhibitory activity of P. americana increases with increasing concentration of the extracts. Administration of methanol extracts of P. americana bark, leaf and root to alloxan-induced diabetic rats resulted in significant (P < 0.05) decreases in AST, ALP, ALT, Total bilirubin, LPO, plasma glucose and significant (P < 0.05) increases in GSH, CAT and SOD. These effects were like that of glibenclamide. The enzyme inhibitory, hepatoprotective, antioxidant and antidiabetic properties of P. americana are some of the benefits derived from its consumption and ethnomedicinal use.


Assuntos
Diabetes Mellitus Experimental , Persea , Ratos , Animais , Antioxidantes/farmacologia , Antioxidantes/química , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Persea/química , Ratos Wistar , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Glibureto/farmacologia , Aloxano , Carboidratos
6.
PeerJ ; 11: e14594, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700000

RESUMO

Background: Cyclists often use high-carbohydrate, low-fiber diets to optimize the glycogen stores and to avoid the gastrointestinal distress during both, the trainings and the competitions. The impact of such dietary changes on gut microbiota is not fully known. Methods: We assessed the abundances of Faecalibacterium prausnitzii, Akkermansia muciniphila, Bifidobacterium spp., and Bacteroides spp. and the fecal pH in 14 amateur cyclists during the racing season. Eleven healthy men formed the control group. Results: Despite significant differences in the diet composition and physical endurance levels of amateur cyclists before the competition season (1st term) and control group (carbohydrates: 52.2% ± 4.9% vs 41.9% ± 6.6%; VO2max: 56.1 ± 6.0 vs 39.7 ± 7.7; p < 0.01; respectively), we did not observe any significant differences in studied gut bacteria abundances or fecal pH between the groups. Although the cyclists' carbohydrates consumption (2nd term) have increased throughout the season (4.48 g/kg b.w. ± 1.56 vs 5.18 g/kg b.w. ± 1.99; p < 0.05), the studied gut bacteria counts and fecal pH remained unchanged. It seems that the amateur cyclists' diet with increased carbohydrates intake does not alter the gut microbiota, but further research is needed to assess the potential impact of even higher carbohydrates consumption (over 6 g/kg b.w.).


Assuntos
Atletas , Resistência Física , Masculino , Humanos , Estações do Ano , Verrucomicrobia , Carboidratos
7.
Phys Chem Chem Phys ; 25(4): 3042-3060, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36607620

RESUMO

D-Mannose is a structural component in N-linked glycoproteins from viruses and mammals as well as in polysaccharides from fungi and bacteria. Structural components often consist of D-Manp residues joined via α-(1→2)-, α-(1→3)-, α-(1→4)- or α-(1→6)-linkages. As models for these oligo- and polysaccharides, a series of mannose-containing disaccharides have been investigated with respect to conformation and dynamics. Translational diffusion NMR experiments were performed to deduce rotational correlation times for the molecules, 1D 1H,1H-NOESY and 1D 1H,1H-T-ROESY NMR experiments were carried out to obtain inter-residue proton-proton distances and one-dimensional long-range and 2D J-HMBC experiments were acquired to gain information about conformationally dependent heteronuclear coupling constants across glycosidic linkages. To attain further spectroscopic data, the doubly 13C-isotope labeled α-D-[1,2-13C2]Manp-(1→4)-α-D-Manp-OMe was synthesized thereby facilitating conformational analysis based on 13C,13C coupling constants as interpreted by Karplus-type relationships. Molecular dynamics simulations were carried out for the disaccharides with explicit water as solvent using the additive CHARMM36 and Drude polarizable force fields for carbohydrates, where the latter showed broader population distributions. Both simulations sampled conformational space in such a way that inter-glycosidic proton-proton distances were very well described whereas in some cases deviations were observed between calculated conformationally dependent NMR scalar coupling constants and those determined from experiment, with closely similar root-mean-square differences for the two force fields. However, analyses of dipole moments and radial distribution functions with water of the hydroxyl groups indicate differences in the underlying physical forces dictating the wider conformational sampling with the Drude polarizable versus additive C36 force field and indicate the improved utility of the Drude polarizable model in investigating complex carbohydrates.


Assuntos
Dissacarídeos , Simulação de Dinâmica Molecular , Animais , Dissacarídeos/química , Manose , Glicosídeos/química , Prótons , Carboidratos , Espectroscopia de Ressonância Magnética , Polissacarídeos/química , Água , Mamíferos
8.
Nutrients ; 15(1)2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36615876

RESUMO

Lignin-carbohydrate complexes (LCCs) are emerging as a new and natural product with pharmacological and nutraceutical potential. It is uncertain, however, whether LCCs have a positive effect on the microbiota of the gut based on the current evidence. Here, the LCC extracted from beechwood (BW-LCC) was used as a substrate for in vitro fermentation. The lignin in BW-LCC consisted of guaiacyl (G) and syringyl (S) units, which are mainly linked by ß-O-4 bonds. After 24 h of in vitro fermentation, the pH had evidently declined. The concentrations of acetic acid and propionic acid, the two main short-chain fatty acids (SCFAs), were significantly higher than in the control group (CK). In addition, BW-LCC altered the microbial diversity and composition of gut microbes, including a reduction in the relative abundance of Firmicutes and an increase in the relative abundance of Proteobacteria and Bacteroidetes. The relative abundance of Escherichia coli-Shigella and Bacteroides were the most variable at the genus level. The genes of carbohydrate-active enzymes (CAZymes) also changed significantly with the fermentation and were related to the changes in microbes. Notably, the auxiliary actives (AAs), especially AA1, AA2, and AA3_2, play important roles in lignin degradation and were significantly enriched and concentrated in Proteobacteria. From this study, we are able to provide new perspectives on how gut microbes utilize LCC.


Assuntos
Carboidratos , Lignina , Lignina/química , Lignina/metabolismo , Fermentação , Carboidratos/química , Bactérias/metabolismo , Ácidos Graxos Voláteis/metabolismo , Proteobactérias/metabolismo
9.
Curr Microbiol ; 80(2): 63, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36595115

RESUMO

Improving the biochemical status of Spirulina platensis will enhance the functional properties of this microalgae. The present study investigated the effects of adding NaHCO3 to the culture medium on the growth rate and biochemical composition, particularly the coproduction of proteins, carbohydrates, and photosynthetic pigments of S. platensis. Spirulina platensis was grown in different NaHCO3 concentrations (0-16 g L-1). NaHCO3 positively affected the biomass production. The growth of S. platensis and biochemical compound content increased with an increase in the NaHCO3 concentration. The microalgae biomass grown on NaHCO3 also contained higher amounts of protein (64.20 ± 4.18% w w-1) and photosynthetic pigments (phycocyanin and chlorophyll a, b, and total). Protein productivity was especially enhanced by approximately 6-25% (from 0.006 ± 0.0030 to 0.025 ± 0.0031 mg L-1 day-1) with the addition of NaHCO3 compared to the control. In contrast, the content of carbohydrates and antioxidant compounds (phenolic, polyphenol oxidase, and peroxidase activities) decreased with culture age and an increase in the NaHCO3 concentration. These results suggest that S. platensis uses NaHCO3 as a carbon source for photosynthesis, biomass production, and acts as a metabolic energy carrier toward the synthesis of proteins and photosynthetic pigments, which are more energy-consuming metabolites than carbohydrates. The addition of NaHCO3 to the culture media is a potentially useful strategy toward improving the protein and photosynthetic pigment productivity of S. platensis.


Assuntos
Bicarbonato de Sódio , Spirulina , Bicarbonato de Sódio/farmacologia , Bicarbonato de Sódio/metabolismo , Clorofila A/metabolismo , Clorofila A/farmacologia , Fotossíntese , Carboidratos , Meios de Cultura/metabolismo , Antioxidantes/farmacologia , Biomassa
10.
Nutrients ; 15(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36678253

RESUMO

As the diet, hormones, amenorrhea, and bone mineral density (BMD) of physique athletes (PA) and gym enthusiasts (GE) are little-explored, we studied those in 69 females (50 PA, 19 GE) and 20 males (11 PA, 9 GE). Energy availability (EA, kcal·kgFFM-1·d-1 in DXA) in female and male PA was ~41.3 and ~37.2, and in GE ~39.4 and ~35.3, respectively. Low EA (LEA) was found in 10% and 26% of female PA and GE, respectively, and in 11% of male GE. In PA, daily protein intake (g/kg body mass) was ~2.9-3.0, whereas carbohydrate and fat intakes were ~3.6-4.3 and ~0.8-1.0, respectively. PA had higher protein and carbohydrate and lower fat intakes than GE (p < 0.05). Estradiol, testosterone, IGF-1, insulin, leptin, TSH, T4, T3, cortisol, or BMD did not differ between PA and GE. Serum IGF-1 and leptin were explained 6% and 7%, respectively, by EA. In non-users of hormonal contraceptives, amenorrhea was found only in PA (27%) and was associated with lower fat percentage, but not EA, BMD, or hormones. In conclusion, off-season dietary intakes, hormone levels, and BMD meet the recommendations in most of the PA and GE. Maintaining too-low body fat during the off-season may predispose to menstrual disturbances.


Assuntos
Amenorreia , Corrida , Humanos , Masculino , Feminino , Amenorreia/etiologia , Densidade Óssea , Leptina , Fator de Crescimento Insulin-Like I , Atletas , Ingestão de Alimentos , Carboidratos
11.
J Int Soc Sports Nutr ; 20(1): 2166366, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36686220

RESUMO

Background: The effects of pre-sleep protein supplementation on endurance athletes remain unclear, particularly whether its potential benefits are due to the timing of protein intake or solely to an increased total protein intake. We assessed the effects of pre-sleep protein supplementation in professional cyclists during a training camp accounting for the influence of protein timing. Methods: Twenty-four professional U23 cyclists (19 ± 1 years, peak oxygen uptake: 79.8 ± 4.9 ml/kg/min) participated in a six-day training camp. Participants were randomized to consume a protein supplement (40 g of casein) before sleep (n = 8) or in the afternoon (n = 8), or an isoenergetic placebo (40 g of carbohydrates) before sleep (n = 8). Indicators of fatigue/recovery (Hooper index, Recovery-Stress Questionnaire for Athletes, countermovement jump), body composition, and performance (1-, 5-, and 20-minute time trials, as well as the estimated critical power) were assessed as study outcomes. Results: The training camp resulted in a significant (p < 0.001) increase in training loads (e.g. training stress score of 659 ± 122 per week during the preceding month versus 1207 ± 122 during the training camp), which induced an increase in fatigue indicators (e.g. time effect for Hooper index p < 0.001) and a decrease in performance (e.g. time effect for critical power p = 0.002). Protein intake was very high in all the participants (>2.5 g/kg on average), with significantly higher levels found in the two protein supplement groups compared to the placebo group (p < 0.001). No significant between-group differences were found for any of the analyzed outcomes (all p > 0.05). Conclusions: Protein supplementation, whether administered before sleep or earlier in the day, exerts no beneficial effects during a short-term strenuous training period in professional cyclists, who naturally consume a high-protein diet.


Assuntos
Desempenho Atlético , Humanos , Suplementos Nutricionais , Carboidratos , Sono , Fadiga , Ciclismo
12.
Biomed Res Int ; 2023: 8150909, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36691472

RESUMO

The global demand for good quality food is going to be increased gradually. Mushrooms are broadly used as healthy nutritious meals. The nutritional values of extracts from four distinct Pleurotus species-Pleurotus ostreatus, Pleurotus sajor-caju, Pleurotus sapidus, and Pleurotus columbinus-were determined in the current study. Firstly, proximate analysis of selected Pleurotus species was performed followed by the Bradford assay to analyze the protein spectrophotometrically; high-performance liquid chromatography (HPLC) was performed for sugar determination while GC-MS was done to determine fatty acids on organic extracts of selected mushrooms. Descriptive statistics were used to calculate the percentages while significance was determined by SPSS statistics. The results depicted that fat, protein, ash, fiber, energy contents, and total carbohydrate were in the range of 0.64-2.02%, 16.07-25.15%, 2.1-9.14%, 6.21-54.12%, 342.20-394.30 kcal/100 g, and 65.66-82.47%, respectively. The protein's maximum concentration was observed in P. ostreatus followed by P. columbinus>P. sajor-caju>P. sapidus, sequentially. Various sugars may or may not be present in selected Pleurotus spps. Among the fatty acids, the prevalence of UFA was more than that of saturated fatty acids among all selected mushrooms. From this study, it is concluded that all four Pleurotus spps. have excellent nutritional composition and can be used as valuable food and a great source of biochemical compounds.


Assuntos
Pleurotus , Pleurotus/química , Carboidratos , Valor Nutritivo , Alimentos , Ácidos Graxos
13.
Molecules ; 28(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36677735

RESUMO

In the past 25 years, a number of efforts have been made toward the development of small molecule interleukin-6 (IL-6) signaling inhibitors, but none have been approved to date. Monosaccharides are a diverse class of bioactive compounds, but thus far have been unexplored as a scaffold for small molecule IL-6-signaling inhibitor design. Therefore, in this present communication, we combined a structure-based drug design approach with carbohydrate building blocks to design and synthesize novel IL-6-signaling inhibitors targeting glycoprotein 130 (gp130). Of this series of compounds, LS-TG-2P and LS-TF-3P were the top lead compounds, displaying IC50 values of 6.9 and 16 µM against SUM159 cell lines, respectively, while still retaining preferential activity against the IL-6-signaling pathway. The carbohydrate moiety was found to improve activity, as N-unsubstituted triazole analogues of these compounds were found to be less active in vitro compared to the leads themselves. Thus, LS-TG-2P and LS-TF-3P are promising scaffolds for further development and study as IL-6-signaling inhibitors.


Assuntos
Antineoplásicos , Interleucina-6 , Antineoplásicos/farmacologia , Carboidratos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Interleucina-6/metabolismo , Simulação de Acoplamento Molecular , Estrutura Molecular , Transdução de Sinais , Relação Estrutura-Atividade , Humanos
14.
Medicina (Kaunas) ; 59(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36676731

RESUMO

This cross-sectional observation study investigated the vitamin D (VD) status in Taiwanese pregnant women and the effects of VD supplementation and macronutrient intake on serum 25-hydroxy-vitamin D (25[OH]D) level. Data on VD intake, daily sunlight exposure, and carbohydrate intake were obtained from 125 pregnant women at 30-37 weeks' gestation. Serum 25[OH]D level was measured before delivery in all enrolled women; and the mean 25(OH)D level was 43 nmol/L or 17.2 ng/mL. The 25(OH)D level was significantly correlated with total VD intake of pregnant women (r = 0.239; p = 0.007). The severe VD deficiency group (n = 16; mean of 25(OH)D level = 8.5 ng/mL) had significantly lower total VD intake and supplementation than the groups with VD deficiency (n = 69), insufficiency (n = 32), and sufficiency (n = 8). Those with ≥400 IU/day total VD intake (including VD from food and supplementation) had significantly higher 25(OH)D concentration than those with <400 IU/day total VD intake. Those with 400 IU/day VD supplementation could significantly increase serum 25(OH)D concentrations for pregnant women. Among 85 pregnant women with carbohydrate intake of ≥300 g/day, serum 25(OH)D levels were negatively correlated with carbohydrate intake (p = 0.031). In conclusion, VD deficiency was highly prevalent in Taiwanese pregnant women. VD supplementation was the most effective method for increasing 25(OH)D concentration in pregnant women. Higher carbohydrate intake might reduce 25(OH)D levels.


Assuntos
Gestantes , Deficiência de Vitamina D , Feminino , Humanos , Gravidez , Estudos Transversais , Suplementos Nutricionais , Vitamina D/uso terapêutico , Deficiência de Vitamina D/complicações , Vitaminas , Carboidratos
15.
Funct Plant Biol ; 50(1): 1-16, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36592984

RESUMO

Non-invasive techniques are needed to enable an integrated understanding of plant metabolic responses to environmental stresses. Raman spectroscopy is one such technique, allowing non-destructive chemical characterisation of samples in situ and in vivo and resolving the chemical composition of plant material at scales from microns to metres. Here, we review Raman band assignments of pigments, structural and non-structural carbohydrates, lipids, proteins and secondary metabolites in plant material and consider opportunities this technology raises for studies in vascular plant physiology.


Assuntos
Análise Espectral Raman , Vibração , Análise Espectral Raman/métodos , Proteínas/química , Carboidratos , Plantas
16.
Chem Commun (Camb) ; 59(9): 1213-1216, 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36629520

RESUMO

A lot of attention has been focused on the functionalization of carbohydrate ligands on specific sizes and shapes of gold nanoparticles (AuNPs), where ultrasmall fluorescent AuNPs have not been well explored for direct imaging. Herein, we have engineered fluorescent gold nanoclusters with sulfated oligo-iduronic acid ligands (I34), which strongly bind to the HB-EGF receptor over FGF2, and regulate EGF receptor-mediated cancer cell homing in both two- and three-dimensional (2D and 3D) cell culture systems. These results offer a new practical and direct imaging tool for carbohydrate research.


Assuntos
Nanopartículas Metálicas , Neoplasias , Ouro/farmacologia , Proteínas de Transporte , Corantes , Receptores ErbB , Carboidratos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico
17.
J Exp Biol ; 226(3)2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36655788

RESUMO

Migration allows animals to track favorable environments and avoid harmful conditions. However, migration is energetically costly, so migrating animals must prepare themselves by increasing their energy stores. Despite the importance of locust migratory swarms, we still understand little about the physiology of locust migration. During long-distance flight, locusts rely on lipid oxidation, despite the fact that lipids are relatively rare in their leaf-based diets. Therefore, locusts and other insect herbivores synthesize and store lipid from ingested carbohydrates, which are also important for initial flight. These data suggest that diets high in carbohydrate should increase lipid stores and the capacity for migratory flight in locusts. As predicted, locust lipid stores and flight performance increased with an increase in the relative carbohydrate content in their food. However, locust flight termination was not associated with complete lipid depletion. We propose potential testable mechanisms that might explain how macronutrient consumption can affect flight endurance.


Assuntos
Gafanhotos , Animais , Gafanhotos/fisiologia , Dieta , Carboidratos , Lipídeos , Voo Animal/fisiologia
18.
Clin Nutr ESPEN ; 53: 33-42, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36657928

RESUMO

BACKGROUND AND AIMS: Previous studies have reported a high prevalence of mental disorders among military organizations. Depression and anxiety are among the most important mental disorders, and depression, suicidal ideation, and violence have been found to be negatively associated with happiness and social support. Therefore, improving mood and increasing happiness can reduce the prevalence of mental disorders in military centers. Diet can improve happiness through specific molecular mechanisms and change our mood by affecting the chemical composition of the brain. Therefore, the present study examined the relationship between the quality and quantity of macronutrients in soldiers' diets with their mood and happiness. METHODS: In the current cross-sectional study, 300 healthy soldiers were selected. Food intake data was collected using 168-item semi-quantitative food frequency questionnaire during the last year of their military training 2-year period. Then, we calculated the quality and quantity of macronutrients. Mood was assessed using the Profile of Mood States (POMS) questionnaire and happiness with the Oxford Happiness Questionnaire (OHQ). RESULTS: The mean ± standard deviation of participants' age was 23.70 ± 1.76 years. A significant relationship was observed between mood score and carbohydrate quantity (OR: 0.32, 95% CI: 0.12-0.88, P-value for trend = 0.03). This suggests that increasing carbohydrate intake improved the participants' mood. No association was found between mood score with protein quantity (OR: 2.15, 95% CI: 0.80-5.75; P-value for trend = 0.12), and gram of fat intake (OR: 1.95, 95% CI: 0.74-5.13; P-value for trend = 0.15). None of the indicators related to macronutrient quality were significantly associated with happiness and mood scores in young soldiers (P ≥ 0.05). CONCLUSIONS: Findings presented in this study showed that increased carbohydrate intake was significantly associated with better mood. However, mood is not related to the amount of proteins and fats and none of the parameters of macronutrient quality. Also, there was no significant relationship between the quantity and quality of macronutrients with happiness score.


Assuntos
Felicidade , Militares , Humanos , Adolescente , Adulto Jovem , Adulto , Estudos Transversais , Nutrientes , Carboidratos
19.
J Am Chem Soc ; 145(3): 1668-1677, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36640106

RESUMO

Multivalent interactions between carbohydrates and proteins enable a broad range of selective chemical processes of critical biological importance. Such interactions can extend from the macromolecular scale (1-10 nm) up to much larger scales across a cell or tissue, placing substantial demands on chemically patterned materials aiming to leverage similar interactions in vitro. Here, we show that diyne amphiphiles with carbohydrate headgroups can be assembled on highly oriented pyrolytic graphite (HOPG) to generate nanometer-resolution carbohydrate patterns, with individual linear carbohydrate assemblies up to nearly 1 µm, and microscale geometric patterns. These are then photopolymerized and covalently transferred to the surfaces of hydrogels. This strategy suspends carbohydrate patterns on a relatively rigid polydiacetylene (persistence length ∼ 16 nm), exposed at the top surface of the hydrogel above the bulk pore structure. Transferred patterns of appropriate carbohydrates (e.g., N-acetyl-d-glucosamine, GlcNAc) enable selective, multivalent interactions (KD ∼ 40 nM) with wheat germ agglutinin (WGA), a model lectin that exhibits multivalent binding with appropriately spaced GlcNAc moieties. WGA binding affinity can be further improved (KD ∼ 10 nM) using diacetylenes that shift the polymer backbone closer to the displayed carbohydrate, suggesting that this strategy can be used to modulate carbohydrate presentation at interfaces. Conversely, GlcNAc-patterned surfaces do not induce specific binding of concanavalin A, and surfaces patterned with glucuronic acid, or with simple carboxylic acid or hydroxyl groups, do not induce WGA binding. More broadly, this approach may have utility in designing synthetic glycan-mimetic interfaces with features from molecular to mesoscopic scales, including soft scaffolds for cells.


Assuntos
Hidrogéis , Lectinas , Lectinas/metabolismo , Carboidratos/química , Aglutininas do Germe de Trigo/química , Concanavalina A
20.
Int J Biol Macromol ; 229: 861-872, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36587642

RESUMO

To develop a characteristic "Lignin-first" strategy, the oxy-organosolv delignification processes under mild conditions were comprehensively investigated. Results showed that lignin yield could achieve about 50 % under the optimum process conditions of ethanol concentration 80 %, temperature 90 °C, liquid to wheat straw ratio 25:1 for powdery-scale substrates, which was 65.0 % higher than that for rod-scale substrates under the same conditions. The lignin structural and carbohydrate component results demonstrated the employment of oxygen induced great quantities of lignin dissolving out on the premise of little carbohydrate component (<1 %) and lignin structural (mainly ß-O-4 units) changes. Moreover, based on the molecular weight and polydiversity comparison results, the aqueous oxygen could transfer homogeneously in mild organosolv system and result in lignin degradation uniformly. Besides, the employment of oxygen assisted in not only extending the massive lignin removal stage to 30 min and 50 min for P-OEEL and R-OEEL respectively, but also boost the delignification rate with comparison to P-EL and R-EL. Lastly, the excellent anti-oxidant properties of lignin from oxy-organosolv process were demonstrated by scavenging DPPH and ABTS radicals. The economic calculations showed that the cost for lignin production were about 1.58USD/g lignin from powdery-scale wheat straw, providing a competitive route for high-value utilize waste biomass.


Assuntos
Lignina , Triticum , Lignina/química , Triticum/química , Solventes/química , Etanol/química , Carboidratos , Hidrólise
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