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Citrus oil (CO) is a commonly used natural flavor with high volatility, which is not conducive to sustained release under food environmental stress. This study constructed novel ß-cyclodextrin/cationic cellulose nanocrystal (ß-CD/C-CNC) complexes via noncovalent interaction, which were used to stabilize CO-loaded Pickering emulsions (PEß-CD/C-CNC). The C-CNC greatly improved the physical stability, droplet dispersion and viscoelasticity of PEß-CD/C-CNC by forming a tight network structure, as verified by rheological behavior. Moreover, C-CNC improved the wettability of ß-CD/C-CNC complexes and enhanced the interaction between adjacent ß-CD/C-CNC complexes. C-CNC also contributed to the interfacial viscoelasticity, hydrated mass, and layer thickness via the interfacial dilational modulus and QCM-D. ß-CD/C-CNC complexes adsorbed on the oil-water interface gave rise to a dense filling layer as a physical barrier, enhancing the sustained-release performance of PEß-CD/C-CNC by limiting diffusion of citrus essential oil into the headspace. This study provides new technical approaches for aroma retention in the food industry.
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Celulosa , Citrus , Preparaciones de Acción Retardada , Emulsiones , Aceites Volátiles , beta-Ciclodextrinas , Emulsiones/química , Citrus/química , beta-Ciclodextrinas/química , Celulosa/química , Aceites Volátiles/química , Preparaciones de Acción Retardada/química , Reología , Viscosidad , Cationes/química , Nanopartículas/químicaRESUMEN
Due to the excellent health benefits of rhamnogalacturonan I (RG-I)-enriched pectin, there has been increasing research interest in its gelling properties. To elucidate its structure-gelation relationship, chemical modifications were used to obtain RG-I-enriched pectin (P11). Then, enzymatic modification was performed to obtain debranched pectins GP11 and AP11, respectively. The effects of RG-I side chains on structural characteristics (especially spatial conformation) and gelling properties were investigated. Among the low-methoxylated pectins (LMPs), AP11, with a loose conformation (Dmax 52 nm) showed the poorest gelling, followed by GP11. In addition to primary structure, spatial conformation (Dmax and Rg) also showed strong correlations (r2 > 0.8) with gelation. We speculate that compact conformation may shorten distance between pectin chains and reduces steric hindrance, contributing to formation of strong gel network. This is particularly important in LMPs with abundant side chains. The results provide novel insights into relationship between spatial conformation and gelling properties of RG-I-enriched pectin.
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Citrus , Geles , Pectinas , Pectinas/química , Geles/química , Citrus/química , Calcio/química , Calcio/metabolismoRESUMEN
To facilitate the application of rhamnogalacturonan-I (RG-I)-enriched pectins (RGPs) as novel, healthy, and gelling food additives, this study compared the structural characteristics and gelling properties of RGPs extracted from citrus peel via four methods (alkali: AK, high-temperature/pressure: TP, citric acid: CA, and enzyme-assisted: EA extractions). AK and CA yielded pectins with the highest RG-I proportions (54.8 % and 51.9 %, respectively) by disrupting the homogalacturonan region; TP and EA increased the RG-I proportions by ~10 %. Among the four methods, AK induced the lowest degree of esterification (DE) (6.7 %) and longer side chains that form strong entanglement, contributing to its highest gel hardness. The relatively low DE (18.5 %) of CA RGP facilitated stable gel formation. Notably, its highly branched RG-I region afforded more intramolecular hydrophobic interactions, making a more highly cross-linked gel network of better gel resilience. In contrast, TP induced the highest DE (57 %) and curved molecular chains; it inhibited Ca2+ binding, entanglement, and intramolecular hydrophobic interactions, and thus no gel formed. EA RGP was associated with the lowest molecular size, rendering it more difficult for Ca2+ to form links, which resulted no gel. These findings offer insights into the relationship among the extraction methods, molecular structures, and gelling properties of RGPs.
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Citrus , Geles , Pectinas , Pectinas/química , Pectinas/aislamiento & purificación , Citrus/química , Geles/química , Esterificación , Interacciones Hidrofóbicas e Hidrofílicas , Ácido Cítrico/química , Reología , Frutas/químicaRESUMEN
INTRODUCTION: Galactooligosaccharides (GOS) are lactogenic prebiotics that exert health benefits by stimulating the growth of different Lactobacillus strains in the gastrointestinal (GI) tract. OBJECTIVES: This study aimed to investigate the mechanism of action of different GOS-enriched lactobacilli in intestinal health. METHODS: Piglets and mice were supplemented with GOS to identify specific enrichment of Lactobacillus. The protective effects of individual GOS-enriched lactobacilli were investigated in Salmonella-infected mice. Macrophage depletion and transcriptome analysis were further performed to assess the involvement of macrophages and the underlying mechanisms of individual lactobacilli. An in vitro cell co-culture system was also used to evaluate the anti-adhesive and anti-invasive activities of lactobacilli against Salmonella in epithelial cells. RESULTS: GOS markedly increased the relative abundance of three lactobacilli including L. delbrueckii, L. johnsonii, and L. reuteri in both piglets and mice. Supplementation with GOS further alleviated Salmonella infection in mice. L. delbrueckii (ATCC®BAA 365™), but not L. johnsonii or L. reuteri, enhanced propionate production in the intestinal tract and ameliorated Salmonella-induced intestinal inflammation and barrier dysfunction by suppressing the JAK2-STAT3 signaling and M1 macrophage polarization. L. johnsonii (BNCC 186110), on the other hand, inhibited Salmonella adhesion and invasion of epithelial cells through competitive exclusion. However, L. reuteri (BNCC 186135) failed to protect mice against Salmonella infection. CONCLUSION: GOS-enriched lactobacilli show a differential role in protecting against Salmonella-induced intestinal barrier dysfunction and inflammation. Our results provide novel insights into the mechanism of action of GOS and individual Lactobacillus strains in the control and prevention of intestinal inflammatory disorders.
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Limosilactobacillus reuteri , Probióticos , Salmonelosis Animal , Animales , Ratones , Porcinos , Lactobacillus , Probióticos/farmacología , Intestinos , Inflamación , Salmonelosis Animal/prevención & controlRESUMEN
The amidation of pectin by amino acids has been widely applied due to its safety and excellent gelling properties. This study systematically examined the effects of pH on the gelling properties of lysine-amidated pectin during amidation and gelation. Pectin was amidated over the range of pH 4-10, and the amidated pectin obtained at pH 10 showed the highest degree of amidation (DA, 27.0 %) due to the de-esterification, electrostatic attraction, and the stretching state of pectin. Moreover, it also exhibited the best gelling properties due to its greater numbers of calcium-binding regions (carboxyl groups) and hydrogen bond donors (amide groups). During gelation, the gel strength of CP (Lys 10) at pH 3-10 first increased and then decreased, with the highest gel strength at pH 8, which was due to the deprotonation of carboxyl groups, protonation of amino groups, and ß-elimination. These results show that pH plays a key role in both amidation and gelation, with distinct mechanisms, and would provide a basis for the preparation of amidated pectins with excellent gelling properties. This will facilitate their application in the food industry.
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Citrus , Lisina , Lisina/metabolismo , Pectinas/química , Esterificación , Concentración de Iones de Hidrógeno , Citrus/química , Geles/químicaRESUMEN
Peroxidase-based assays are the most extensively used in bioanalytical sensors because of their simple colorimetric readout and high sensitivity owing to enzymatic signal amplification. To improve the stability, modification, and cost of protein-based enzymes, such as horseradish peroxidase (HRP), various enzyme mimics, such as DNAzymes and nanozymes, have emerged over the last few decades. In this study, we compared the peroxidase activities of HRP, a G-quadruplex (G4)-hemin DNAzyme, and Fe3O4 nanozymes in terms of activity and stability under different conditions. The reactions were much slower at pH 7 than at pH 4. At pH 4, the turnover rate of HRP (375 s-1) was faster than that of G4 DNAzyme (0.14 s-1) and Fe3O4 (6.1 × 10-4 s-1, calculated by surface Fe concentration). When normalized to mass concentrations, the trend was the same. Through observation of the reaction for a long time of 2 h, the changes in the color and UV-vis spectra were also different for these catalysts, indicating different reaction mechanisms among these catalysts. Moreover, different buffers and nanozyme sizes were found to influence the activity of the catalysts. Fe3O4 showed the highest stability compared to HRP and G4 DNAzyme after a catalytic reaction or incubation with H2O2 for a few hours. This study helps to understand the properties of catalysts and the development of novel catalysts with enzyme-mimicking activities for application in various fields.
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ADN Catalítico , G-Cuádruplex , ADN Catalítico/química , Hemina/química , Peroxidasa de Rábano Silvestre/química , Peróxido de Hidrógeno , Peroxidasa , PeroxidasasRESUMEN
(-)-Epigallocatechin (EGC) has good health benefits, but its chemical stability is low. Pectin hydrogels have potential for the encapsulation and delivery of EGC, but they are limited by porous networks and poor mechanical properties. In this study, protein (whey protein isolate and caseinate)-reinforced pectin hydrogel beads (HBPEC-WPI and HBPEC-CAS) were developed to overcome these limitations. The results showed that HBPEC-CAS was a superior delivery system for EGC. HBPEC-CAS had a compact network structure, mainly because of the hydrogen bonds that formed between caseinate and pectin. Moreover, the EGC encapsulation efficiency of HBPEC-CAS (2.4%) reached 92.23 %; HBPEC-CAS (2.4%) could also delay the release of EGC in an aqueous environment, while ensuring its sufficient release in a simulated gastrointestinal environment. Notably, EGC was chemically stabilized in HBPEC-CAS (2.4%) during a 6-day storage period at 37 °C through the inhibition of its epimerization, oxidation, dimerization, and trimerization. The numerous hydroxyl groups in EGC readily interacted with the exposed amino acid residues in caseinate and created more protective sites. This study developed a strategy for protein-reinforced pectin hydrogel development and approaches for the protection of tea polyphenols; the findings offer useful insights for the tea-based food and beverage industry.
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Catequina , Hidrogeles , Hidrogeles/química , Pectinas/química , Caseínas , TéRESUMEN
Citrus fruits are consumed in large quantities worldwide due to their attractive aromas and taste, as well as their high nutritional values and various health-promoting effects, which are due to their abundance of nutrients and bioactives. In addition to water, carbohydrates, vitamins, minerals, and dietary fibers are important nutrients in citrus, providing them with high nutritional values. Citrus fruits are also rich in various bioactives such as flavonoids, essential oils, carotenoids, limonoids, and synephrines, which protect from various ailments, including cancer and inflammatory, digestive, and cardiovascular diseases. The composition and content of nutrients and bioactives differ significantly among citrus varieties, fruit parts, and growth stages. To better understand the nutrient and bioactive profiles of citrus fruits and provide guidance for the utilization of high-value citrus resources, this review systematically summarizes the nutrients and bioactives in citrus fruit, including their contents, structural characteristics, and potential health benefits. We also explore the composition variation in different citrus varieties, fruits parts, and growth stages, as well as their health-promoting effects and applications.
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Citrus , Frutas , Frutas/química , Citrus/química , Nutrientes , Flavonoides/análisis , VitaminasRESUMEN
Flavonoids have been attracting increasing research interest because of their multiple health promoting effects. However, many flavonoids with similar structures are present in foods, often at low concentrations, which increases the difficulty of their separation and identification. Liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (LC-Q-TOF-MS/MS) has become one of the most widely used techniques for flavonoid detection. LC-Q-TOF-MS/MS can achieve highly efficient separation by LC; it also provides structural information regarding flavonoids by Q-TOF-MS/MS. This review presents a comprehensive summary of the scientific principles and detailed methodologies (e.g., qualitative determination, quantitative determination, and data processing) of LC-Q-TOF-MS/MS specifically for food flavonoids. It also discusses the recent applications of LC-Q-TOF-MS/MS in determination of flavonoid types and contents in agricultural products, changes in their structures and contents during food processing, and metabolism in vivo after consumption. Moreover, it proposes necessary technological improvements and potential applications. This review would facilitate the scientific understanding of theory and technique of LC-Q-TOF-MS/MS for flavonoid detection, and promote its applications in food and health industry.
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Flavonoides , Espectrometría de Masas en Tándem , Flavonoides/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/métodos , Cromatografía Liquida , AlimentosRESUMEN
Food bioactives exhibit various health-promoting effects and are widely used in functional foods to maintain human health. After oral intake, bioactives undergo complex biological processes before reaching the target organs to exert their biological effects. However, several factors may reduce their bioavailability. Colloidal systems have attracted special attention due to their great potential to improve bioavailability and bioefficiency. Herein, we focus on the importance of in vivo studies of the biological fates of bioactives delivered by colloidal systems. Increasing evidence demonstrates that the construction, composition, and physicochemical properties of the delivery systems significantly influence the in vivo biological fates of bioactives. These results demonstrate the great potential to control the in vivo behavior of food bioactives by designing specific delivery systems. We also compare in vivo and in vitro models used for biological studies of the fate of food bioactives delivered by colloidal systems. Meanwhile, the significance of the gut microbiota, targeted delivery, and personalized nutrition should be carefully considered. This review provides new insight for further studies of food bioactives delivered by colloidal systems, as well as scientific guidance for the reasonable design of personalized nutrition.
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Hydroxylated polymethoxyflavones (PMFs) are a unique class of flavonoid compounds mainly found in citrus plants. We investigated the anti-inflammatory effects of one major 5-hydroxy PMF, namely 5-demethylnobiletin (5DN) and its metabolites 5, 3'-didemethylnobiletin (M1), 5, 4'-didemethylnobiletin (M2), and 5, 3', 4'-tridemethylnobiletin (M3) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. The results showed that M2 and M3 produced stronger inhibitory effects on the production of nitric oxide (NO) than their parent compound at non-cytotoxic concentrations. Western blotting and real-time PCR analyses demonstrated that M2 and M3 significantly decreased iNOS and COX-2 gene expression. The results also showed that M1 and M3 induced heme oxygenase-1(HO-1) gene expression. Overall, our results demonstrated that metabolites of 5DN significantly inhibited LPS-induced inflammation in RAW 264.7 macrophage cells and generally possessed more potent anti-inflammatory activity than the parent compound, 5DN.
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The reliable, readily accessible and label-free measurement of aptamer binding remains a challenge in the field. Recent reports have shown large changes in the intrinsic fluorescence of DNA upon the formation of G-quadruplex and i-motif structures. In this work, we examined whether DNA intrinsic fluorescence can be used for studying aptamer binding. First, DNA hybridization resulted in a drop in the fluorescence, which was observed for A30/T30 and a 24-mer random DNA sequence. Next, a series of DNA aptamers were studied. Cortisol and Hg2+ induced fluorescence increases for their respective aptamers. For the cortisol aptamer, the length of the terminal stem needs to be short to produce a fluorescence change. However, caffeine and adenosine failed to produce a fluorescence change, regardless of the stem length. Overall, using the intrinsic fluorescence of DNA may be a reliable and accessible method to study a limited number of aptamers that can produce fluorescence changes.
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Aptámeros de Nucleótidos , G-Cuádruplex , Hidrocortisona , Aptámeros de Nucleótidos/química , ADN , Hibridación de Ácido NucleicoRESUMEN
Carotenoids in plant foods are sources of pro-vitamin A and nutrients with several health benefits, including antioxidant and anticancer activities. However, humans cannot synthesize carotenoids de novo and must obtain them from the diet, typically via plant foods. We review the chemical changes of carotenoids in plant foods from farm to table and nutrition, including nutrient release and degradation during processing and metabolism in vivo. We also describe the influencing factors and proposals corresponding to enhancing the release, retention and utilization of carotenoids, thus benefiting human health. Processing methods influence the release and degradation of carotenoids, and nonthermal processing may optimize processing effects. The carotenoid profile, food matrix, and body status influence the digestion, absorption, and biotransformation of carotenoids in vivo; food design (diet and carotenoid delivery systems) can increase the bioavailability levels of carotenoids in the human body. In this review, the dynamic fate of carotenoids in plant foods is summarized systematically and deeply, focusing on changes in their chemical structure; identifying critical control points and influencing factors to facilitate carotenoid regulation; and suggesting multi-dimensional strategies based on the current state of food processing industries to achieve health benefits for consumers.
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While polyvalent metal ions and heating can both degrade nucleic acids, we herein report that a combination of them leads to stabilization. After incubating 4 mM various metal ions and DNA oligonucleotides at 95 °C for 3 h at pH 6 or 8, metal ions were divided into four groups based on gel electrophoresis results. Mg2+ can stabilize DNA at pH 6 without forming stable nanoparticles at room temperature. Co2+, Cu2+, Cd2+, Mn2+ and Zn2+ all protected the DNA and formed nanoparticles, whereas the nanoparticles formed with Fe2+ and Ni2+ were so stable that they remained even in the presence of EDTA. At pH 8, Ce3+ and Pb2+ showed degraded DNA bands. For Mg2+, better protection was achieved with higher metal and DNA concentrations. By monitoring temperature-programmed fluorescence change, a sudden drop in fluorescence intensity attributable to the lower critical solution temperature (LCST) transition of DNA was found to be around 80 °C for Mg2+, while this transition temperature decreased with increasing Mn2+ concentration. The unexpected thermal stability of DNA enabled by metal ions is useful for extending the application of DNA at high temperatures, forming coordination-driven nanomaterials, and it might offer insights into the origin of life on the early Earth.
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Cadmio , Plomo , ADN , Ácido Edético , Iones , Oligonucleótidos , TemperaturaRESUMEN
Foodborne probiotics substantially impact human health. Thus, there is an urgent need for real-time and in situ detection of targeted probiotics. In this paper, a novel nanopopcorn fluorescent probe based on DNA-mediated Au@Ag@silica was designed and shown to display plasma resonance characteristics that generated more hot spots. This led to >18-fold greater fluorescence of indocyanine green dye with strong emission in the near-infrared (NIR-I and NIR-II) regions. Moreover, the new fluorescent probe exhibited high stability and low biotoxicity, having a strong linear relationship (R2 = 0.9615) with Lactobacillus Plantarum concentration over the range of 105-109 cfu/mL; it enabled in vivo tracing of exogenous probiotics. Compared with the traditional inductively coupled mass spectrometry (ICP-MS), the results are consistent (Correlation coefficient = 0.994), but the analysis time is much reduced by 89.6%. It is remarkable that the probe enabled real-time and in situ monitoring of target probiotic behavior in a simple, robust, and effective manner.
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Técnicas Biosensibles , Lactobacillus plantarum , Probióticos , ADN , Sondas de ADN , Colorantes Fluorescentes/química , Humanos , Dióxido de Silicio/químicaRESUMEN
A comprehensive understanding of the relationships between the structure and function is critical for the targeted preparation of functional pectins. In this study, we compared the alleviating effects of five orange pectins (200 mg/kg) extracted using acid (P2), alkali (P10), cellulase (C), acid + cellulase (P2 + C), and alkali + cellulase (P10 + C) on dextran sodium sulfate-induced acute colitis. The physiological and histopathological indicators revealed that the alleviating effects were most significant for P10 + C, followed by P10, P2 + C, P2, and C. P10 + C increased the diversity and relative abundance of Akkermansia, leading to increased generation of colonic short-chain fatty acids as well as mRNA and protein expressions of GPR43, GPR109A, claudin-1, ZO-1, and occludin. Therefore, proinflammatory cytokines were decreased, and anti-inflammatory cytokines were increased. A compact conformation of P10 + C contributed to the alleviation effects on acute colitis. Alkali + cellulase-extracted orange pectin with a compact conformation has potential as adjuvant treatment for intestinal inflammation.
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Citrus sinensis , Colitis , Animales , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/genética , Colon , Citocinas , Sulfato de Dextran , Modelos Animales de Enfermedad , Ratones , Ratones Endogámicos C57BL , PectinasRESUMEN
Natural compounds have tremendous potential to regulate glucose metabolism, but conventional methods for studying their bioactivities are usually labor intensive. Here, hypoglycemic properties in 22 selected food-derived compounds were examined using molecular docking. The results indicated that curcumin is an inhibitor of both α-glucosidase and dipeptidyl-peptidase 4 (DPP-4), which are important for glycemic control. These effects of curcumin were also confirmed by enzymatic determination in vitro. Furthermore, curcumin significantly improved diet-induced hyperglycemia (e.g., fasting plasma glucose levels and glycogen storage in muscle or liver) in mice. This might be attributed to its inhibitory effects on the activities of α-glucosidase and DPP-4 in vivo. Curcumin also upregulated the expression of genes (e.g., glucagon-like peptide 1) related to DPP-4 activity in the small intestine. In conclusion, curcumin is a potential ingredient of functional foods used for diet-induced hyperglycemia management. PRACTICAL APPLICATIONS: Curcumin has been widely used as a colorant in the food industry. Moreover, a growing number of studies have described its diverse biological functions, such as anti-inflammatory, anti-oxidant, and anti-angiogenic activities. Thus, curcumin is regarded as a potential ingredient in functional foods. Our results highlighted the hyperglycemic effect of curcumin, suggesting that curcumin may be included in food products for hyperglycemic patients.
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Curcumina , Inhibidores de la Dipeptidil-Peptidasa IV , Hiperglucemia , Animales , Curcumina/química , Curcumina/farmacología , Inhibidores de la Dipeptidil-Peptidasa IV/farmacología , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Ratones , Simulación del Acoplamiento Molecular , alfa-GlucosidasasRESUMEN
The metabolic fate of dietary compounds is closely related to their biological functions. Pterostilbene (PT) is a methylated stilbene found in many plant foods. Herein, we investigated gastrointestinal biotransformation and tissue distribution of PT in mice fed with 0.05% PT (w/w) for 5 weeks. PT and its major metabolites i.e. PT sulfate (PT-S), pinostilbene, pinostilbene sulfate, hydroxylated PT and hydroxylated PT sulfate were identified and quantified in the mucosa and content of the digestive tissues, blood, urine and vital organs. The results showed PT underwent demethylation, hydroxylation and conjugation in the small intestine, while the conjugated metabolites were largely deconjugated in the colon. Anaerobic fermentation with mouse cecal bacteria demonstrated the microbiota mediated deconjugation and demethylation of PT-S and PT, respectively. In conclusion, oral consumption of PT led to extensive biotransformation in mouse gastrointestinal tract and the metabolites of PT might play important roles in the bioactivity of PT.