Recent advances on the stability of dietary polyphenols

A study on the qualitative analysis of lotus seedpod oligomeric procyanidins during digestion, absorption and colonic fermentation based on UPLC-Q-Exactive/MS

Polyphenols have potent antioxidant properties, but are easily degraded in the gastrointestinal tract, greatly limiting their application as dietary supplements. Therefore, the composition changes of lotus seedpod oligomeric procyanidins (LSOPC) in the gastrointestinal digestion, colonic fermentation and their absorption in Caco-2 cell monolayer were studied. The extracted LSOPC were identified using UPLC-Q-Exactive/MS, and a total of 47 compounds were identified. After gastrointestinal digestion, succinic acid, protocatechuic acid, p-Hydroxybenzoic acid, azelaic acid, and dihydroxyphenylacetic acid were released. Compared to gastrointestinal digestion, the total phenolic content and antioxidant capacity of LSOPC were significantly higher after colonic fermentation (P < 0.05). In addition, catechin (2.5%) crossed the Caco-2 cell monolayer and entered systemic circulation. Most of the LSOPC were not absorbed but instead entered the colon, where they were degraded to phenolic acids by gut microbiota. At the same time, unabsorbed LSOPC and their metabolites modulated the composition of gut microbiota, decreasing the Firmicutes/Bacteroidetes ratio and promoting the generation of short-chain fatty acids, especially acetic acid. Phenylacetic acid, p-Hydroxyphenylpropionic acid, p-coumaric acid, dihydroxyphenyl-ɤ-valerolactone, and 4-(3,4'-dihydroxyphenyl) valeric acid could not be detected until after colonic fermentation. It is the first time to systematically clarify compositional transformations of LSOPC during gastrointestinal digestion and colonic fermentation, which will pave the way for increasing the economic value of lotus seedpod and provide a theoretical basis for polyphenols as dietary supplements.

Chemical characteristics and bioactivity potential of polysaccharide extracts and purified fractions from Arctic brown macroalgae

Macroalgae growing in the polar regions are exposed to extreme environment conditions and may induce differences in the structural and bioactive properties of their polysaccharides. Six brown macroalgae viz. kelp species - Saccharina latissima, Laminaria digitata, and Alaria esculenta; rockweed Fucus distichus; and filamentous macroalgae - Chorda filum and Chordaria flageliformis, from the Arctic were investigated for polysaccharides and their bioactivity. Among them, C. filum and C. flageliformis are least studied. Crude polysaccharide extracts (CPEs), extracted in water using ultrasonication, were found be dominated by fucoidan and alginate based on their monosaccharide composition analyzed using HPAEC-PAD. The CPEs showed up to 66 % radical scavenging activity in DPPH, ABTS and H2O2 antioxidant assays, while 93 % inhibition activity was observed in α-glucosidase anti-glycemic assay. The CPEs lacked pigments but contained minor amount of polyphenols. Purified polysaccharide fractions (PPFs) were obtained from the CPEs by ion-exchange chromatography. The monosaccharide composition and colorimetric analysis indicated enhanced purity of polysaccharides and absence of polyphenols in the PPFs. However, the antioxidant and antiglycemic activities of PPFs were lower than CPEs. We attributed the higher bioactivities in the crude extracts to synergistic interactions that may stabilize key active constituents.

Exploring the mechanism of flavonoids modification by dimerization strategies and their potential to enhance biological activity

Flavonoid dimers are being focused due to their particular structure that links two units through CC or C-O-C bonds. This paper provides a comprehensive and systematic overview of the reaction mechanism of flavonoid dimerization and discusses their synthesis process and methods to devise an ideal preparation scheme of flavonoid dimers. Given the polyphenolic hydroxyl groups of dimerized flavonoids as well as their unique bridging molecular structures, we preliminarily explored the link between conformation and function, and discovered their several reinforced bioactivities compared to flavonoid monomers, such as hypolipidemic, antidiabetic, and neuroprotective activities as well as other potential. In contrast to monomer, luteolin dimer demonstrated the remarkably higher activity in inhibiting α-amylase, α-glucosidase and the growth of A. niger (IC50: 0.86 μM), which is even comparable to acarbose and amphotericin B. Therefore, dimerization strategy represents a promising method for structural modification of flavonoid to potential applications in food supplements or pharmaceuticals.

Improved uptake of anthocyanins-loaded nanoparticles based on phenolic acid-grafted zein and lecithin

Anthocyanins (ACNs) exhibit various physiological activities but have low bioavailability. This study aimed to improve cellular uptake and permeability of ACNs by utilizing phenolic acids grafted zein and lecithin (ZLAs) as the carrier. With the highest grafting rate achieved in rosmarinic acid (RA)-zein at 39.79 ± 0.40 % using alkali treatment, the grafted zein samples were characterized through spectroscopy, NMR, and analysis of physicochemical properties. Ferulic acid (FA)-ZLAs exhibited the smallest particle size (69.72 ± 0.50 nm) and PDI value of 0.206 ± 0.012. Multi-spectroscopy indicated hydrogen bonding and hydrophobic forces were the major forces to stabilize ACNs. Moreover, carrier binding including electrostatic interaction effectively enhanced processing, thermal degradation, color, and gastrointestinal stability. In Caco-2 monolayers, FA-ZLAs significantly improved cellular transport efficiency, resulting in up to a 1.9-fold enhancement. RA-ZLAs exhibited the strongest antioxidant activity. This work proposes a feasible strategy for stabilizing ACNs and propelling their use in dietary supplements.

Stability and degradation mechanism of (-)-epicatechin in thermal processing

(-)-Epicatechin (EC) is a commonly dietary phytochemical that presents multi-physiological activities on human health. Thermal processing is a common method to extract EC, albeit likely to degrade EC considering its thermal instability. In this study, an 85-min non-durable bathing incubation assay was designed to simulate the state of EC in boiling water while cooking. Monitoring of degradation products was performed using ultra-performance liquid chromatography combined with electrospray ionization quadrupole tandem mass spectrometric detection (UPLC-ESI-TSQ-MS/MS). The results revealed that ca. 65.2 % loss of EC was detected in the first 10 min, and over 99.5 % of EC was degraded within 30 min. A total of 22 degradation products were identified based on retention time, full and tandem MS data were the first to be comprehensively reported. Isomerization, oxidation, hydroxylation, dimerization, and ring cleavage were the main chemical reactions that occurred for EC in boiling aqueous solution.

Computational and in vitro evaluation of sumac-derived ©Rutan compounds towards Sars-CoV-2 Mpro inhibition

The emergence of the SARS-CoV-2 virus caused the COVID-19 outbreak leading to a global pandemic. Natural substances started being screened for their antiviral activity by computational and in-vitro techniques. Here, we evaluated the anti-SARS-CoV-2 main protease (Mpro) efficacy of ©Rutan, which contains five polyphenols (R5, R6, R7, R7', and R8) extracted from sumac Rhus coriaria L. We obtained three fractions after large-scale purification: fraction 1 held R5, fraction 2 consisted of R6, R7 and R7', and fraction 3 held R8. In vitro results showed their anti-Mpro potential: IC50 values of R5 and R8 made 42.52 µM and 5.48 µM, respectively. Further, we studied Mpro-polyphenol interactions by in silico analysis to understand mechanistic extrapolation of Rutan binding nature with Mpro. We extensively incorporated a series of in silico techniques. Initially, for the docking protocol validation, redocking of the co-crystal ligand GC-376* to the binding pocket of Mpro was carried out. The representative docked complexes were subjected to long-range 500 ns molecular dynamics simulations. The binding free energy (BFE in kcal/mol) of components were calculated as follows: R8 (-104.636) > R6 (-93.754) > R7' (-92.113) > R5 (-81.115) > R7 (-67.243). In silico results of R5 and R8 correspond with their in vitro outcomes. Furthermore, the per-residue decomposition analysis showed C145, E166, and Q189 residues as the hotspot residues for components contributing to maximum BFE energies. All five components effectively interact with the catalytic pocket of Mpro and form stable complexes that allow the estimation of their inhibitory activity. Assay kit analyses revealed that Rutan and its components have effective anti-SARS-CoV-2 Mpro inhibitory activity.

Effect of the Type of Herbal Preparations (Powdered Plant Material vs. Dry Ethanolic Extracts) on the Bioaccessibility of Bearberry (Arctostaphylos uva-ursi (L.) Spreng.) Phytochemicals in Simulated Digestion Conditions

The main aim of this study was to determine the potential bioaccessibility of bearberry phytochemicals influenced by the type of herbal preparations. Herbal preparations-powdered plant materials and dry extracts obtained using various ethanol concentrations (0%, 20%, 40%, 60%, 80%, and 100%) were subjected to simulated gastric or gastrointestinal digestion for the evaluation of the bioaccessibility of the phytochemicals. The phytochemical characterization of the plant material, dry extracts, and potentially bioaccessible fractions was performed using high-performance liquid chromatography (HPLC) and spectrophotometric assays. The content of the main compounds, i.e., arbutin, hydroquinone, hyperoside, pentagalloylglucose, and picein, as well as the total phenolic content and in vitro antioxidant activity through the ABTS•+-scavenging activity and Fe3+-reducing power were determined. The bioaccessibility of arbutin, i.e., the main compound in bearberry, was high, in most cases exceeding 95%, and was generally unaffected by the experimental factors; however, the changes in the content of the other compounds, the total phenolic content, and the antioxidant activity were more prominent and influenced by the type of the herbal preparation and the stage of digestion. Given the compromise between the abundance of the bearberry phytochemicals, the antioxidant activity, and the resulting potential bioaccessibility of these phytochemicals, the dry extracts prepared with 40% ethanol seem to be the most promising for phytopharmaceutical purposes and functional food applications.

The current state of knowledge about thermal processing of edible seeds; a special emphasis on their bioactive constituents and antioxidant activity

Thermal processing can alter the biological activity of seed phytochemicals in various ways, thus improving shelf life, bioavailability, oxidative stability, and oil yield; it can also decrease the content of antinutritional compounds, reduce cytotoxic activity and increase the total phenolic content of the seeds. However, this treatment can also inactivate beneficial compounds, including phenolics. This review describes the effect of different thermal processing methods on the content, activity, and bioavailability of chemical compounds from different edible seeds. The outcome is dependent on the method, temperature, time of processing, and type of seeds. Although thermal processing has many benefits, its precise effect on different species requires further clarification to determine how it influences their phytochemical content and biological activity, and identify the optimal conditions for processing.

Stabilization of Picea abies Spruce Bark Extracts within Ice-Templated Porous Dextran Hydrogels

Porous hydrogels have brought more advantages than conventional hydrogels when used as chromatographic materials, controlled release vehicles for drugs and proteins, matrices for immobilization or separation of molecules and cells, or as scaffolds in tissue engineering. Polysaccharide-based porous hydrogels, in particular, can address challenges related to bioavailability, solubility, stability, and targeted delivery of natural antioxidant compounds. Their porous structure enables the facile encapsulation and controlled release of these compounds, enhancing their therapeutic effectiveness. In this context, in the present study, the cryogelation technique has been adopted to prepare novel dextran (Dx)-based porous hydrogels embedding polyphenol-rich natural extract from Picea abies spruce bark (SBE). The entrapment of the SBE within the Dx network was proved by FTIR, SEM, and energy-dispersive X-ray spectroscopy (EDX). SEM analysis showed that entrapment of SBE resulted in denser cryogels with smaller and more uniform pores. Swelling kinetics confirmed that higher concentrations of Dx, EGDGE, and SBE reduced water uptake. The release studies demonstrated the effective stabilization of SBE in the Dx-based cryogels, with minimal release irrespective of the approach selected for SBE incorporation, i.e., during synthesis (~3-4%) or post-synthesis (~15-16%). In addition, the encapsulation of SBE within the Dx network endowed the hydrogels with remarkable antioxidant and antimicrobial properties. These porous biomaterials could have broad applications in areas such as biomedical engineering, food preservation, and environmental protection, where stability, efficacy, and safety are paramount.

Ultrasound-assisted glycosylation of ovalbumin and dextran conjugate carrier for anthocyanins and their stability evaluation

Anthocyanins (AC) are vulnerable to degradation when affected by external factors. The present study employed ultrasound-assisted glycosylation of ovalbumin (OVA) and dextran (Dex) to generate conjugate carrier for AC to improve its stability. The results showed that sonication significantly improved the progression of Maillard reaction to OVA. Compared to traditional glycosylation, ultrasound treatment showed a higher degree of grafting, a lower number of free-SH, and smaller particle size and uniform distribution. The SDS-PAGE results indicated covalent interaction. Intrinsic fluorescence (INF), Fourier transform infrared spectroscopy (FTIR), and Circular dichroism (CD) analysis results suggested that ultrasound-assisted glycosylation altered the OVA structure. The scanning electron microscope (SEM) and X-ray diffractometer (XRD) observed that the ultrasound-assisted complex had a more compact and smoother structure and protein unfolding were better. The protein solubility increased significantly after glycosylation. Thermal gravimetric analysis (TGA) and Differential scanning calorimetry (DSC) indicated that the glycosylated conjugates can significantly improve the thermal stability of AC In addition, the AC showed an improved processing and storage stability when conjugated with glycosylated carrier. The glycosylated protein-anthocyanins complex may help provide new ideas and scientific basis for the development of naturally sourced anthocyanins-relevant products in pharmaceutical and food industry applications.

Prunus persica (L.) Batsch blossom soluble dietary fiber synergia polyphenol improving loperamide-induced constipation in mice via regulating stem cell factor/C-kit, NF-κB signaling pathway and gut microbiota

This study aimed to investigate the ameliorating effects of peach blossom soluble dietary fiber (PBSDF) and polyphenol (PBP) combinations on loperamide (Lop)-induced constipation in mice, together with the possible mechanism of action. The results demonstrated that the combined use of PBSDF and PBP could synergistically accelerate the gastrointestinal transit rate and gastric emptying rate, shorten first red fecal defecation time, accelerate the frequency of defecation, regulate the abnormal secretion of gastrointestinal neurotransmitters and pro-inflammatory cytokines, and down-regulate the expressions of AQP3 and AQP8. Western blotting and RT-qPCR analysis confirmed that PBSDF + PBP up-regulated the protein and mRNA expressions of SCF and C-kit in SCF/C-kit signaling pathway, and down-regulated pro-inflammatory mediator expressions in NF-κB signaling pathway. 16S rRNA sequencing showed that the diversity of gut microbiota and the relative abundance of specific strains, including Akkermansia, Bacteroides, Ruminococcus, Lachnospiraceae_NK4A136_group, and Turicibacter, rehabilitated after PBSDF + PBP intervention. These findings suggested that the combination of a certain dose of PBSDF and PBP had a synergistic effect on attenuating Lop-induced constipation, and the synergistic mechanism in improving constipation might associated with the regulating NF-κB and SCF/C-kit signaling pathway, and modulating the specific gut strains on constipation-related systemic types. The present study provided a novel strategy via dietary fiber and polyphenol interactions for the treatment of constipation.

Enzymatic acylation of cyanidin-3-O-glucoside with aromatic and aliphatic acid methyl ester: Structure-stability relationships of acylated derivatives

Anthocyanins are water-soluble pigments, but they tend to be unstable in aqueous solutions. Modification of their molecular structure offers a viable approach to alter their intrinsic properties and enhance stability. Aromatic and aliphatic acid methyl esters were used as acyl donors in the enzymatic acylation of cyanidin-3-O-glucoside (C3G), and their analysis was conducted using ultraperformance liquid chromatography-mass spectrometry (UPLC-MS). The highest conversion rate achieved was 96.41 % for cyanidin-3-O-(6″-feruloyl) glucoside. Comparative evaluations of stability revealed that aromatic acyl group-conjugated C3G exhibited superior stability enhancement compared with aliphatic acyl group derivatives. The stability of aliphatic C3G decreased with increasing carbon chain length. The molecular geometries of different anthocyanins were optimized, and energy level calculations using density functional theory (DFT) identified their sites with antioxidant activities. Computational calculations aligned with the in vitro antioxidant assay results. This study provided theoretical support for stabilizing anthocyanins and broadened the application of acylated anthocyanins as food colorants and nutrient supplements.

Anthocyanins as natural bioactives with anti-hypertensive and atherosclerotic potential: Health benefits and recent advances

BACKGROUND

Hypertension is a highly prevalent chronic metabolic illness affecting individuals of all age groups. Furthermore, it is a significant risk factor for the development of atherosclerosis (AS), as a correlation between hypertension and AS has been observed. However, the effective treatments for either of these disorders appear to be uncommon.

METHODS

A systematic search of articles published in PubMed, Web of Science, ScienceDirect, Scopus, and Google Scholar databases over the last decade was performed using the following keywords: hypertension, AS, anthocyanins, antioxidants, gut microbes, health benefits, and bioactivity.

RESULTS

The available research indicates that anthocyanin consumption can achieve antioxidant effects by inducing the activation of intracellular nuclear factor erythroid 2-related factor (Nrf2) and the expression of antioxidant genes. Moreover, previous reports showed that anthocyanins can enhance the human body's ability to fight against inflammation and cancer through the inhibition of inflammatory factors and the regulation of related signaling pathways. They can also protect the blood vessels and nervous system by regulating the production and function of endothelial nitric oxide synthase (eNOS). Gut microorganisms play an important role in various chronic diseases. Our research has also investigated the role of anthocyanins in the metabolism of the gut microbiota, leading to significant breakthroughs. This study not only presents a unique strategy for reducing the risk of cardiovascular diseases (CVDs) without the need for medicine but also provides insights into the development and utilization of intestinal probiotic dietary supplements.

CONCLUSION

In this review, different in vitro and in vivo studies have shown that anthocyanins slow down the onset and progression of hypertension and AS through different mechanisms. In addition, gut microbial metabolites also play a crucial role in diseases through the gut-liver axis.

Artichoke By-Product Extracts as a Viable Alternative for Shelf-Life Extension of Breadsticks

The upcycling of agricultural by-products and the extension of the shelf-life of staple foods represent crucial strategies for mitigating the consequences of food losses and enhancing the competitiveness of the agri-food industry, thus facilitating the attainment of higher financial revenues. This is particularly relevant for global artichoke cultivation, where 60-80% of its biomass is discarded annually. The present study investigated the potential of using non-stabilized polyphenol-rich extracts from the main artichoke by-products (bracts, leaves, and stems) to fortify and extend the shelf-life of breadsticks. The incorporation of hydroalcoholic extracts at two addition levels (1000-2000 ppm) resulted in an increased antioxidant capacity and oxidative stability of fortified breadsticks. Rheological tests revealed that the fortification did not affect the dough's workability, with the exception of the leaf extract. While a slight deterioration in texture was observed, the shelf-life of breadsticks was significantly extended, particularly at the highest levels of addition, without any visible alteration in their appearance. The stem extract demonstrated the most promising outcomes, exhibiting a maximum increase of 69% in antioxidant capacity (DPPH) and an extension of the estimated shelf-life by 62% in the resulting breadsticks, prompting the potential for utilizing them to develop nutritious and healthy snacks with extended shelf-life.

Nano-Formulations of Natural Antioxidants for the Treatment of Liver Cancer

Oxidative stress is a key factor in the pathological processes that trigger various chronic liver diseases, and significantly contributes to the development of hepatocarcinogenesis. Natural antioxidants reduce oxidative stress by neutralizing free radicals and play a crucial role in the treatment of free-radical-induced liver diseases. However, their efficacy is often limited by poor bioavailability and metabolic stability. To address these limitations, recent advances have focused on developing nano-drug delivery systems that protect them from degradation and enhance their therapeutic potential. Among the several critical benefits, they showed to be able to improve bioavailability and targeted delivery, thereby reducing off-target effects by specifically directing the antioxidant to the liver tumor site. Moreover, these nanosystems led to sustained release, prolonging the therapeutic effect over time. Some of them also exhibited synergistic effects when combined with other therapeutic agents, allowing for improved overall efficacy. This review aims to discuss recent scientific advances in nano-formulations containing natural antioxidant molecules, highlighting their potential as promising therapeutic approaches for the treatment of liver cancer. The novelty of this review lies in its comprehensive focus on the latest developments in nano-formulations of natural antioxidants for the treatment of liver cancer.

Effects of the dose of administration, co-antioxidants, food matrix, and digestion-related factors on the in vitro bioaccessibility of rosmarinic acid - A model study

This study aimed to determine the effect of the administration dose, combinations with co-antioxidants (vitamin C, caffeic acid, chlorogenic acid, catechin, rutin), and different food matrices (cooked and lyophilized hen eggs, chicken breast, soybean seeds, potatoes) on the potential bioaccessibility of rosmarinic acid (RA) in simulated digestion conditions, depending on the digestion stage (gastric and intestinal) and the contribution of physicochemical and biochemical digestion factors. The in vitro bioaccessibility of RA depended on the digestion stage and conditions. The physicochemical factors were mainly responsible for the bioaccessibility of RA applied alone. The higher RA doses improved its bioaccessibility, especially at the intestinal stage of digestion. Furthermore, the addition of vitamin C and protein-rich food matrices resulted in enhanced intestinal bioaccessibility of RA. In the future, the knowledge of factors influencing the bioaccessibility of RA can help enhance its favorable biological effects and therapeutic potential.

Polysaccharide-polyphenol interactions: a comprehensive review from food processing to digestion and metabolism

Most studies on the beneficial effects of polyphenols on human health have focused on polyphenols extracted using aqueous organic solvents, ignoring the fact that a portion of polyphenols form complexes with polysaccharides. Polysaccharides and polyphenols are interrelated, and their interactions affect the physicochemical property, quality, and nutritional value of foods. In this review, the distribution of bound polyphenols in major food sources is summarized. The effect of food processing on the interaction between polyphenols and cell wall polysaccharides (CWP) is discussed in detail. We also focus on the digestion, absorption, and metabolic behavior of polysaccharide-polyphenol complexes. Different food processing techniques affect the interaction between CWP and polyphenols by altering their structure, solubility, and strength of interactions. The interaction influences the free concentration and extractability of polyphenols in food and modulates their bioaccessibility in the gastrointestinal tract, leading to their major release in the colon. Metabolism of polyphenols by gut microbes significantly enhances the bioavailability of polyphenols. The metabolic pathway and product formation rate of polyphenols and the fermentation characteristics of polysaccharides are affected by the interaction. Furthermore, the interaction exhibits synergistic or antagonistic effects on the stability, solubility, antioxidant and functional activities of polyphenols. In summary, understanding the interactions between polysaccharides and polyphenols and their changes in food processing is of great significance for a comprehensive understanding of the health benefits of polyphenols and the optimization of food processing technology.

Microencapsulation of highly concentrated polyphenolic compounds from purple corn pericarp by spray-drying with various biomacromolecules

Colored corn pericarp contains unusually high amounts of industrially valuable phytochemicals, such as anthocyanins, flavanols, flavonoids, and phenolic acids. Polyphenols were extracted in an aqueous solution and spray-dried to produce microencapsulates using four carrier materials, namely, maltodextrin (MD), gum arabic (GA), methylcellulose (MC), and skim milk powder (SMP) at three concentrations (1, 2, and 3 %, respectively). The encapsulates were evaluated for their polyphenolic contents using spectrophotometric techniques and HPLC analyses, and their antioxidant properties were evaluated using four different assays. The physicochemical properties of encapsulates were analyzed by measuring the zeta potential (ZP), particle size distribution, water solubility index (WSI), water absorption index (WAI), and color parameters. Structural and thermal properties were evaluated using Fourier transform infrared spectroscopy (FTIR), optical profilometry, and differential scanning calorimetry (DSC) analyses. Comparative analysis of structural characteristics, particle size distribution, zeta potential, WSI, WAI, and aw of the samples confirmed the successful formulation of encapsulates. The microencapsulates embedded with 1 % concentrations of MD, MC, GA, or SMP retained polyphenolic compounds and exhibited noteworthy antioxidant properties. The samples encapsulated with GA or MD (1 %) demonstrated superior physicochemical, color, and thermal properties. Comprehensive metabolomic analysis confirmed the presence of 38 phytochemicals in extracts validating the spray-drying process.

Bioaccessibility of Rosmarinic Acid and Basil (Ocimum basilicum L.) Co-Compounds in a Simulated Digestion Model-The Influence of the Endogenous Plant Matrix, Dose of Administration and Physicochemical and Biochemical Digestion Environment

The objective of this study is to determine the effect of endogenous plant matrix components, dose and digestion-related factors on the bioaccessibility of rosmarinic acid and basil co-compounds in in vitro digestion conditions. Different forms of administration, i.e., basil raw plant material, dry extract, and isolated rosmarinic acid at various doses, were applied for the digestion experiment. To evaluate the contribution of biochemical and physicochemical digestion factors, samples were subjected to a full digestion process or treated only with a digestion fluid electrolyte composition without using biochemical components (i.e., digestion enzymes and bile salts), and bioaccessibility was monitored at the gastric and intestinal steps of digestion. The results showed that the components of the endogenous raw plant matrix significantly limited the bioaccessibility of rosmarinic acid and basil co-compounds, especially at the gastric stage of digestion. Physicochemical digestion factors were mainly responsible for the bioaccessibility of basil phytochemicals. Higher doses allowed maintenance of bioaccessibility at a relatively similar level, whereas the most negative changes in bioaccessibility were induced by the lowest doses. In conclusion, the determination of the bioaccessibility of bioactive phytochemicals from basil and factors influencing bioaccessibility may help in better prediction of the pro-health potential of this plant.

Wheat Bran Polyphenols Ameliorate DSS-Induced Ulcerative Colitis in Mice by Suppressing MAPK/NF-κB Inflammasome Pathways and Regulating Intestinal Microbiota

Wheat bran (WB) is the primary by-product of wheat processing and contains a high concentration of bioactive substances such as polyphenols. This study analyzed the qualitative and quantitative components of polyphenols in wheat bran and their effects on ulcerative colitis (UC) using the dextran sulfate sodium (DSS)-induced colitis model in mice. The potential mechanism of wheat bran polyphenols (WBP) was also examined. Our findings indicate that the main polyphenol constituents of WBP were phenolic acids, including vanillic acid, ferulic acid, caffeic acid, gallic acid, and protocatechuic acid. Furthermore, WBP exerted remarkable protective effects against experimental colitis. This was achieved by reducing the severity of colitis and improving colon morphology. Additionally, WBP suppressed colonic inflammation via upregulation of the anti-inflammatory cytokine IL-10 and downregulation of pro-inflammatory cytokines (TNF-α, IL-6, IL-1β) in colon tissues. Mechanistically, WBP ameliorated DSS-induced colitis in mice by inhibiting activation of the MAPK/NF-κB pathway. In addition, microbiome analysis results suggested that WBP modulated the alteration of gut microbiota caused by DSS, with an enhancement in the ratio of Firmicutes/Bacteroidetes and adjustments in the number of Helicobacter, Escherichia-Shigella, Akkermansia, Lactobacillus, Lachnospiraceae_NK4A136_group at the genus level. To conclude, the findings showed that WBP has excellent prospects in reducing colonic inflammation in UC mice.

Encapsulation of pomegranate polyphenols by ionic gelation: Strategies for improved retention and controlled release

This study aimed at producing pectin hydrogel beads by ionic gelation proce to carry pomegranate extract (PE) evaluating approaches to increase its retention and protect the polyphenols from environmental conditions that interfere in the stability and color of these compounds, such as the pH of the medium. Several strategies were tested to reduce the mass transfer and consequently increase its retention. The insertion of a filler (gelatinized starch), the employment of different concentrations from the external environment, the adsorption using blank pectin-starch beads, and the electrostatic coating using chitosan were performed. The release of entrapped compounds over time was employed to evaluate the release pattern of PE in water media. Diffusion coefficients calculated from these experiments were then used to estimate the PE release behavior. The encapsulation efficiency (EE) was significantly improved (42 % to 101 %) when equalizing the concentration of the external medium with that from the beads formulation. Furthermore, the increase in the PE concentration was proportional to the rise in the mechanical strength (MS) of the beads which indicates a modification of internal structure due to the presence of polyphenols. The adsorption was efficient in entrapping the active compound, and despite the high PE content observed for all beads (average value of 2960.26 mg of gallic acid equivalent/100 g sample), they had the lowest diffusion coefficient from the release in water media. Finally, the coating was able to reduce the release rate in most of the tests (DAB uncoated = 0.5 DAB coated), however, during the electrostatic deposition a loss of about 32 % of the phenolic compounds in the chitosan solution was observed which led to a reduced EE. Despite the obtention of retarded release, coating studies need to be improved. Some adjustments in the execution of this technique are necessary so that the losses are reduced and the process becomes viable for the use of beads in food.

Polyphenolic Compounds in Extracts from Roasted Grapevine Canes: An Investigation for a Circular Approach to Increase Sustainability in the Viticulture Sectors

In this study, we compared the polyphenolic composition of the roasted grapevine wood chips of four Vitis vinifera cultivars-namely, Sorbara, Grasparossa, Malbo Gentile, and Spergola. These waste byproducts have the potential as infusion chips for the aging of alcoholic beverages and vinegars, contributing to an enriched sensory profile. Roasting amplifies aromatic nuances and triggers the depletion of crucial bioactive compounds, including polyphenols. We investigated the extent of polyphenolic loss in the ethanolic extract of roasted grapevine chips to repurpose this waste byproduct and assess its potential. We assessed the levels of trans-resveratrol, trans-ε-viniferin, trans-piceatannol, and the main resveratrol trimer. Our findings indicated a significant decrease in polyphenol content as the roasting temperature increased, from 16.85-21.12 mg GAE/g for grapevine chips roasted at 120 °C to 3.10-7.77 mg GAE/g for those roasted at 240 °C. This study also highlights notable genotypic differences in polyphenolic content. Among the red grape cultivars analyzed, Sorbara exhibited the highest levels (7.77-21.12 mg/GAEg), whereas the white grape cultivar Spergola showed the lowest polyphenolic content (3.10-16.85 mg/GAEg). These findings not only contribute to the scientific understanding of polyphenol stability but also hold practical implications for the enhancement of aged beverages, as well as advancing sustainable practices in the viticulture industries.

Bioavailability and Antioxidant Activity of Rambutan (Nephelium lappaceum) Peel Polyphenols during in Vitro Simulated Gastrointestinal Digestion, Caco-2 Monolayer Cell Model Application, and Colonic Fermentation

The bioavailability of rambutan peel polyphenols (RPPs) was studied via in vitro simulated digestion, a Caco-2 monolayer cell model, and colonic fermentation. Total phenolic content of RPPs decreased with the progress of the simulated digestion. A total of 38 phenolic compounds were identified during the digestion and colonic fermentation, of which 12 new metabolites were found during colonic fermentation. The possible biotransformation pathways were inferred. Geraniin was transformed into corilagin, ellagic acid, and gallic acid during the digestion and colonic fermentation. Ellagic acid could be further transformed into urolithin under the action of intestinal microbiota. The transformation of ellagitannins could be beneficial to transport on Caco-2 monolayer cell. The antioxidant capacity of RPPs increased with the progress of gastrointestinal digestion. Furthermore, RPPs could increase the yield of short-chain fatty acids, decrease the pH value, promote the growth of beneficial bacteria, and inhibit the growth of pathogenic Escherichia coli/Shigella during colonic fermentation.

Ultrasound-Assisted Encapsulation of Phytochemicals for Food Applications: A Review

The use of phytochemicals as natural food additives is a topic of interest for both academic and food industry communities. However, many of these substances are sensitive to environmental conditions. For this reason, encapsulation is usually performed prior to incorporation into food products. In this sense, ultrasound-assisted encapsulation is an emerging technique that has been gaining attention in this field, bringing important advantages for the production of functional food products. This review article covered applications published in the last five years (from 2019 to 2023) on the use of ultrasound to encapsulate phytochemicals for further incorporation into food. The ultrasound mechanisms for encapsulation, its parameters, such as reactor configuration, frequency, and power, and the use of ultrasound technology, along with conventional encapsulation techniques, were all discussed. Additionally, the main challenges of existing methods and future possibilities were discussed. In general, ultrasound-assisted encapsulation has been considered a great tool for the production of smaller capsules with a lower polydispersity index. Encapsulated materials also present a higher bioavailability. However, there is still room for further developments regarding process scale-up for industrial applications. Future studies should also focus on incorporating produced capsules in model food products to further assess their stability and sensory properties.

Fabrication and Characterization of Complex Coacervation: The Integration of Sesame Protein Isolate-Polysaccharides

The exceptional biocompatibility of emulsion systems that rely on stabilizing protein-polysaccharide particles presents extensive possibilities for the transportation of bioactive carriers, making them highly promising for various biological applications. The current work aimed to explore the phenomenon of complex coacervation between sesame protein isolate (SPI) and four distinct polysaccharides, namely, Arabic gum (GA), carrageenan (CAR), sodium carboxymethyl cellulose (CMC), and sodium alginate (SA). The study objective was achieved by fabricating emulsions through the blending of these polymers with oil at their maximum turbidity level (φ = 0.6), followed by the measurement of their rheological properties. The turbidity, ζ-potential, and particle size were among the techno-parameters analyzed to assess the emulsion stability. The microstructural characterization of the emulsions was conducted using both transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Furthermore, the functional properties were examined using Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The SPI incorporated with SA, CMC, and CAR reached the maximum turbidity (0.2% w/v) at a ratio of 4:1, corresponding to the pH values of 4.5, 3, or 3.5, respectively. The SPI-GA mixture exhibited the maximum turbidity at a ratio of 10:1 and pH 4.5. Results from the FTIR and XRD analyses provided evidence of complex formation between SPI and the four polysaccharides, with the electrostatic and hydrogen bond interactions facilitating the binding of SPI to these polysaccharides. SPI was bound to the four polysaccharides through electrostatic and hydrogen bond interactions. The SPI-CMC and SPI-SA emulsions were more stable after two weeks of storage.

Post pH-driven encapsulation of polyphenols in next-generation foods: principles, formation and applications

To meet the needs of a growing global population (∼10 billion by 2050), there is an urgent demand for sustainable, healthy, delicious, and affordable next-generation foods. Natural polyphenols, which are abundant in edible plants, have emerged as promising food additives due to their potential health benefits. However, incorporating polyphenols into food products presents various challenges, including issues related to crystallization, low water-solubility, limited bioavailability, and chemical instability. pH-driven or pH-shifting approaches have been proposed to incorporate polyphenols into the delivery systems. Nevertheless, it is unclear whether they can be generally used for the encapsulation of polyphenols into next-generation foods. Here, we highlight a post pH-driven (PPD) approach as a viable solution. The PPD approach inherits several advantages, such as simplicity, speed, and environmental friendliness, as it eliminates the need for heat, organic solvents, and complex equipment. Moreover, the PPD approach can be widely applied to different polyphenols and food systems, enhancing its versatility while also potentially contributing to reducing food waste. This review article aims to accelerate the implementation of the PPD approach in the development of polyphenol-fortified next-generation foods by providing a comprehensive understanding of its fundamental principles, encapsulation techniques, and potential applications in plant-based foods.

Dendrobium as a new natural source of bioactive for the prevention and treatment of digestive tract diseases: A comprehensive review with future perspectives

BACKGROUND

The incidence of diseases related to the digestive tract is on the rise, with many types of complex etiologies. Dendrobium nobile Lindl. is a famous Traditional Chinese Medicine (TCM) rich in many bioactives proven to be beneficial in several health diseases related to inflammation and oxidative stress.

PURPOSE

At present, despite the availability of various therapeutic clinical drugs used for the treatment of digestive tract diseases, resistance emergence and existence of several side effects warrant for the developing of novel drugs for improved effects on digestive tract diseases.

METHODS

"Orchidaceae", "Dendrobium", "inflammation", "digestive tract", and "polysaccharide" were used as search terms to screen the literature. The therapeutic use of Dendrobium related to digestive tract diseases relative to known polysaccharides and other bioactive compounds were derived from online databases, including Web of Science, PubMed, Elsevier, Science Direct, and China National Knowledge Infrastructure, as well as relevant information on the known pharmacological actions of the listed phytochemicals.

RESULTS

To better capitalize upon Dendrobium for preventing and treating diseases related to digestive tract, this review summarizes bioactives in Dendrobium reported of potential in digestive tract diseases management and their underlying action mechanisms. Studies revealed that Dendrobium encompasses diverse classes including polysaccharides, phenolics, alkaloids, bibenzyls, coumarins, phenanthrene and steroids, with polysaccharide as the major class. Dendrobium exerts various health effects on a variety of disease related to the digestive tract. Action mechanisms involve antioxidant, anti-inflammatory, anti-apoptotic, antioxidant, anticancer, alongside the regulation of some key signaling pathways.

CONCLUSION

Overall, Dendrobium appears as a promising TCM source of bioactives that has the potential to be further developed into nutraceuticals for digestive tract diseases compared to current drug treatments. This review highlights for Dendrobium potential effects with future perspectives for needed future research to maximize the use of bioactive compounds from Dendrobium for digestive tract disease treatment. A compile of Dendrobium bioactives is also presented alongside methods for their extraction and enrichment for potential incorporation in nutraceuticals.

Optimization of Phytochemical-Rich Citrus maxima Albedo Extract Using Response Surface Methodology

In the present study, response surface methodology (RSM) and Box-Behnken design (BBD) were employed to optimize the conditions for the extraction of C. maxima albedo from agricultural waste, to obtain notable phytochemicals. Ethanol concentration, extraction temperature, and extraction time were included as key factors contributing to the extraction. The results showed that the optimum extraction condition for C. maxima albedo was 50% (v/v) aqueous ethanol at 30 °C for 4 h, which provided total phenolic contents and total flavonoid contents at 15.79 mg of gallic equivalent/g dry weight (DW) and 4.50 mg of quercetin equivalent/g DW, respectively. Considerable amounts of hesperidin and naringenin at 161.03 and 3430.41 µg/g DW, respectively, were detected in the optimized extract using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). The extract was later subjected to a test for its enzyme-inhibitory activities against key enzymes relevant to Alzheimer's disease (AD), obesity, and diabetes as well as for its mutagenicity potential. Among enzyme inhibitory activities, the extract showed the highest inhibitory strength against β-secretase (BACE-1), which is a drug target for AD treatment. The extract was also devoid of mutagenicity properties. Overall, this study demonstrated a simple and optimal extraction procedure for C. maxima albedo with a significant quantity of phytochemicals, health benefits, and genome safety.

Physicochemical Properties, Antioxidant Capacity, and Bioavailability of Laurus nobilis L. Leaf Polyphenolic Extracts Microencapsulated by Spray Drying

Laurel (Laurus nobilis L.) leaves are a rich source of polyphenols with the potential for use in functional foods, where the main obstacle is their low stability and bioavailability, which can be improved by spray drying (SD). This research examined the influence of SD parameters, including inlet temperature (120, 150, and 180 °C), carrier type (β-cyclodextrin (β-CD); β-CD + maltodextrin (MD) 50:50; β-CD + gum arabic (GA) 50:50), and sample:carrier ratio (1:1, 1:2 and 1:3) on the physicochemical properties, encapsulation efficiency, polyphenolic profile, antioxidant capacity and bioaccessibility of laurel leaf polyphenols. The highest encapsulation efficiency was achieved at a sample:carrier ratio 1:2 and the temperature of 180 °C by using either of the applied carriers. However, the application of β-CD + MD 50:50 ensured optimal solubility (55.10%), hygroscopicity (15.32%), and antioxidant capacity (ORAC 157.92 μmol Trolox equivalents per g of powder), while optimal moisture content (3.22%) was determined only by temperature, demanding conditions above 150 °C. A total of 29 polyphenols (dominantly flavonols) were identified in the obtained powders. SD encapsulation increased the bioaccessibility of laurel flavonols in comparison to the non-encapsulated extract by ~50% in the gastric and ~10% in the intestinal phase, especially for those powders produced with carrier mixtures.

Prospects for the application of traditional Chinese medicine network pharmacology in food science research

There has always been a particular difficulty with in-depth research on the mechanisms of food nutrition and bioactivity. The main function of food is to meet the nutritional needs of the human body, rather than to exert a therapeutic effect. Its relatively modest biological activity makes it difficult to study from the perspective of general pharmacological models. With the popularity of functional foods and the concept of dietary therapy, and the development of information and multi-omics technology in food research, research into these mechanisms is moving towards a more microscopic future. Network pharmacology has accumulated nearly 20 years of research experience in traditional Chinese medicine (TCM), and there has been no shortage of work from this perspective on the medicinal functions of food. Given the similarity between the concept of 'multi-component-multi-target' properties of food and TCM, we think that network pharmacology is applicable to the study of the complex mechanisms of food. Here we review the development of network pharmacology, summarize its application to 'medicine and food homology', and propose a methodology based on food characteristics for the first time, demonstrating its feasibility for food research. © 2023 Society of Chemical Industry.

Health-Promoting Properties and Potential Application in the Food Industry of Citrus medica L. and Citrus × clementina Hort. Ex Tan. Essential Oils and Their Main Constituents

Citrus is an important genus in the Rutaceae family, with high medicinal and economic value, and includes important crops such as lemons, orange, grapefruits, limes, etc. The Citrus species is rich sources of carbohydrates, vitamins, dietary fibre, and phytochemicals, mainly including limonoids, flavonoids, terpenes, and carotenoids. Citrus essential oils (EOs) consist of several biologically active compounds mainly belonging to the monoterpenes and sesquiterpenes classes. These compounds have demonstrated several health-promoting properties such as antimicrobial, antioxidant, anti-inflammatory, and anti-cancer properties. Citrus EOs are obtained mainly from peels, but also from leaves and flowers, and are widely used as flavouring ingredients in food, cosmetics, and pharmaceutical products. This review focused on the composition and biological properties of the EOs of Citrus medica L. and Citrus clementina Hort. Ex Tan and their main constituents, limonene, γ-terpinene, myrcene, linalool, and sabinene. The potential applications in the food industry have been also described. All the articles available in English or with an abstract in English were extracted from different databases such as PubMed, SciFinder, Google Scholar, Web of Science, Scopus, and Science Direct.

Ultrasound-assisted development and characterization of novel polyphenol-loaded pullulan/trehalose composite films for fruit preservation

A novel food packaging film was developed by incorporating a tea polyphenols-loaded pullulan/trehalose (TP@Pul/Tre) into a composite film with ultrasound-assisted treatment of dual-frequency (20/35 kHz, 40 W/L) for 15 min to assess the physicochemical and mechanical properties of a composite film. The optimized ultrasound-assisted significantly increases elongation at break, tensile strength, and improves the composite film's UV/water/oxygen barrier properties. Structure analysis using attenuated total reflectance-Fourier transform infrared, X-ray diffraction and thermal stability revealed that these improvements were achieved through ultrasound-enhanced H-bonds, more ordered molecular arrangements, and good intermolecular compatibility. Besides, the ultrasound-assisted TP@Pul/Tre film has proven to have good antibacterial performance against Escherichia coli and Staphylococcus aureus, with approximately 100 % lethality at 4 h and 8 h, respectively. Moreover, the ultrasound-assisted TP@Pul/Tre film effectively delayed moisture loss, oxidative browning, decay, and deterioration in fresh-cut apples and pears, thereby extending their shelf life. Thus, ultrasound has proved to be an effective tool for improving the quality of food packaging films, with a wide range of applications.

Whole grain benefit: synergistic effect of oat phenolic compounds and β-glucan on hyperlipidemia via gut microbiota in high-fat-diet mice

Increasing evidence has confirmed that whole grain oats are effective in regulating hyperlipidemia. However, which specific ingredient is crucial remains unclear. This study focused on which whole grain components, oat phenolic compounds (OPC) or oat β-glucan (OBG), can regulate lipid metabolism and gut microbiota. The experiment unveiled that OPC and/or OBG not only reduced the body weight and fasting blood glucose (FBG) but also regulated serum and hepatic lipid levels in high-fat-diet (HFD) fed mice. There was no significant difference in the regulatory effects of OPC and OBG (p > 0.05). The combination of OPC and OBG (OPC + OBG) significantly decreased the body weight (p < 0.01) and reduced the blood glucose (p < 0.01) and lipid profile levels (p < 0.01). The real-time quantitative PCR (RT-qPCR) study revealed that OPC + OBG significantly altered mRNA expression related to lipid metabolism. Histopathological analysis showed that OPC + OBG improved liver lipid deposition as well as liver oxidative stress (p < 0.05). In addition, OPC + OBG combination regulated the gut microbiota community phenotype and increased probiotics. OPC + OBG significantly increased the abundance of Bacteroidetes and reduced the abundance of Firmicutes (p < 0.05) compared with the OPC and OBG fed mice. In conclusion, OPC + OBG has a synergistic effect in alleviating hyperlipidemia via lipid metabolism and gut microbiota composition. This finding also provided a potential justification for the advantages of whole grains in preventing hyperlipidemia.

Recent advances in the biosynthesis, bioavailability, toxicology, pharmacology, and controlled release of citrus neohesperidin

Neohesperidin (hesperetin 7-O-neohesperidoside), a well-known flavanone glycoside widely found in citrus fruits, exhibits a variety of biological activities, with potential applications ranging from food ingredients to therapeutics. The purpose of this manuscript is to provide a comprehensive overview of the chemical, biosynthesis, and pharmacokinetics profiles of neohesperidin, as well as the therapeutic effects and mechanisms of neohesperidin against potential diseases. This literature review covers a wide range of pharmacological responses elicited by Neohesperidin, including neuroprotective, anti-inflammatory, antidiabetic, antimicrobial, and anticancer activities, with a focus on the mechanisms of those pharmacological responses. Additionally, the mechanistic pathways underlying the compound's osteoporosis, antiulcer, cardioprotective, and hepatoprotective effects have been outlined. This review includes detailed illustrations of the biosynthesis, biopharmacokinetics, toxicology, and controlled release of neohesperidine. Neohesperidin demonstrated a broad range of therapeutic and biological activities in the treatment of a variety of complex disorders, including neurodegenerative, hepato-cardiac, cancer, diabetes, obesity, infectious, allergic, and inflammatory diseases. Neohesperidin is a promising therapeutic candidate for the management of various etiologically complex diseases. However, further in vivo and in vitro studies on mechanistic potential are required before clinical trials to confirm the safety, bioavailability, and toxicity profiles of neohesperidin.