Effects of α-Casein on the Absorption of Blueberry Anthocyanins and Metabolites in Rat Plasma Based on Pharmacokinetic Analysis

Exploring high hydrostatic pressure effects on anthocyanin binding to serum albumin and food-derived transferrins

This study investigated the effects of high hydrostatic pressure (HHP) on the binding interactions of cyanindin-3-O-glucoside (C3G) to bovine serum albumin, human serum albumin (HSA), bovine lactoferrin, and ovotransferrin. Fluorescence quenching revealed that HHP reduced C3G-binding affinity to HSA, while having a largely unaffected role for the other proteins. Notably, pretreating HSA at 500 MPa significantly increased its dissociation constant with C3G from 24.7 to 34.3 μM. Spectroscopic techniques suggested that HSA underwent relatively pronounced tertiary structural alterations after HHP treatments. The C3G-HSA binding mechanisms under pressure were further analyzed through molecular dynamics simulation. The localized structural changes in HSA under pressure might weaken its interaction with C3G, particularly polar interactions such as hydrogen bonds and electrostatic forces, consequently leading to a decreased binding affinity. Overall, the importance of pressure-induced structural alterations in proteins influencing their binding with anthocyanins was highlighted, contributing to optimizing HHP processing for anthocyanin-based products.

Design of a liposome casein hydrogel as an efficient front-end homeostatic anthocyanin loading system

Proteins have been studied and applied to improve the stability of anthocyanins (ACNs), but the changes in the pH microenvironment during the preparation of steady-state systems are often ignored, and more attention is given to the stability of the system after preparation. In this study, we propose the "anthocyanin front-end homeostasis strategy", which involves designing a system can protect anthocyanins under acidic conditions so that more anthocyanin prototypes can be loaded inside the protein. Anthocyanins are encapsulated in liposomes (Lip) at pH 3.0 and combined with casein methacrylate (CSMA) to form Anthocyanin-loaded liposomes/CSMA hydrogel (Lip@ACNs/CSMA), with good physical properties and good blood compatibility. The system increased the hydrogen peroxide scavenging capacity by 1.16 mg Vc equiv./mg ACNs and the cellular antioxidant activity by 17.55 μM quercetin/100 mg ACNs, the photo and thermal storage stability increased by 36.50 % and 30.71 %, the digestive rate increased by 17.50 %, and the biological availability increased by 0.0049 mg/mL. This study designed a liposome casein hydrogel as an efficient front-end homeostatic anthocyanin loading system and provided a new approach for improving the stability of anthocyanins.

Unlocking the health potential of anthocyanins: a structural insight into their varied biological effects

Anthocyanins have become increasingly important to the food industry due to their colorant features and many health-promoting activities. Numerous studies have linked anthocyanins to antioxidant, anti-inflammatory, anticarcinogenic properties, as well as protection against heart disease, certain types of cancer, and a reduced risk of diabetes and cognitive disorders. Anthocyanins from various foods may exhibit distinct biological and health-promoting activities owing to their structural diversity. In this review, we have collected and tabulated the key information from various recent published studies focusing on investigating the chemical structure effect of anthocyanins on their stability, antioxidant activities, in vivo fate, and changes in the gut microbiome. This information should be valuable in comprehending the connection between the molecular structure and biological function of anthocyanins, with the potential to enhance their application as both colorants and functional compounds in the food industry.

Protein and Peptide-Based Nanotechnology for Enhancing Stability, Bioactivity, and Delivery of Anthocyanins

Anthocyanin, a unique natural polyphenol, is abundant in plants and widely utilized in biomedicine, cosmetics, and the food industry due to its excellent antioxidant, anticancer, antiaging, antimicrobial, and anti-inflammatory properties. However, the degradation of anthocyanin in an extreme environment, such as alkali pH, high temperatures, and metal ions, limits its physiochemical stabilities and bioavailabilities. Encapsulation and combining anthocyanin with biomaterials could efficiently stabilize anthocyanin for protection. Promisingly, natural or artificially designed proteins and peptides with favorable stabilities, excellent biocapacity, and wide sources are potential candidates to stabilize anthocyanin. This review focuses on recent progress, strategies, and perspectives on protein and peptide for anthocyanin functionalization and delivery, i.e., formulation technologies, physicochemical stability enhancement, cellular uptake, bioavailabilities, and biological activities development. Interestingly, due to the simplicity and diversity of peptide structure, the interaction mechanisms between peptide and anthocyanin could be illustrated. This work sheds light on the mechanism of protein/peptide-anthocyanin nanoparticle construction and expands on potential applications of anthocyanin in nutrition and biomedicine.

Effects of α-casein on the excretion of blueberry anthocyanins via urine and feces: Analysis of their bioavailability

Anthocyanins are bioactive compounds found in blueberries. However, their poor bioavailability restricts their functional activities in vivo, which is a challenging issue in the application of blueberry anthocyanins. Our current study utilized α-casein as a carrier and analyzed its influence on the excretion of blueberry anthocyanins in urine and feces in a rat model to reflect the enhanced bioavailability of blueberry anthocyanins by α-casein in vivo. The results showed that α-casein suppressed the excretive content of blueberry anthocyanins (malvidin-3-O-galacoside (M3G), cyanidin-3-O-glucoside (C3G), and delphinidin-3-O-glucoside (D3G)), increased the content of metabolites in urine (syringic acid, ferulic acid, 4-hydroxybenzoic acid, and vanillic acid), and reduced metabolite content in feces (syringic acid, ferulic acid, and gallic acid), indicating that α-casein was effective in controlling the excretion of blueberry anthocyanins and their metabolites. In summary, these results provided sufficient evidence for the positive effects of α-casein on the bioavailability of blueberry anthocyanins.

Anthocyanins from Aronia melanocarpa Bound to Amylopectin Nanoparticles: Tissue Distribution and In Vivo Oxidative Damage Protection

The in vivo applications of anthocyanins are limited by their instability. Nano-encapsulation using amylopectin nanoparticles (APNPs) stabilizes anthocyanins to deliver them to tissues to ameliorate their physiological functions. Herein, rats are fed four Aronia melanocarpa anthocyanins encapsulated with APNPs, and their subsequent distributions and bioactivity in nine tissues are revealed using UHPLC-MS. Among digestive tissues, the concentration of the APNP-protected cyanidin 3-O-arabinoside in the stomach is 134.54% of that of the free anthocyanin, while among non-digestive tissues, the APNP-protected cyanidin 3-O-glucoside concentration in the lungs improved by 125.49%. Concentration maxima "double peaks" in the liver and kidney arise from different modes of transport. Sustained release of anthocyanins from anthocyanin-APNPs and stable concentration curves suggest controlled delivery, with most APNPs consumed in the digestive system. APNPs did not affect the overall anthocyanin absorption time or tissues. The superoxide dismutase and malondialdehyde concentrations indicate that APNPs enhance the oxidative damage protection in vivo.

Protein-binding approaches for improving bioaccessibility and bioavailability of anthocyanins

Color is an important characteristic of food. Over the last 15 years, more attention has been paid to natural colorants because of the rising demand for clean-label food products. Anthocyanins, which are a group of phytochemicals responsible for the purple, blue or red hues of many plants, offer a market advantage. In addition, anthocyanin-rich foods are associated with protection against cardiovascular disease, thrombosis, diabetes, cancer, microbial-based disorders, neurological disorders, and vision ailments. However, the real health value of anthocyanins, whether as a natural colorant or a functional ingredient, is dependent on the ultimate bioaccessibility and bioavailability in the human body. Many animal and human clinical studies revealed that, after intake of anthocyanin-rich foods or anthocyanin extracts, only trace amounts (< 1% of ingested content) of anthocyanins or their predicted metabolites were detected in plasma after a standard blood draw, which was indicative of low bioavailability of anthocyanins. Protein binding to anthocyanins is a strategy that has recently been reported to enhance the ultimate bioactivity, bioaccessibility, and bioavailability of anthocyanins as compared to anthocyanins delivered without a protein carrier. Therefore, in this review, we address anthocyanin properties in food processing and digestion, anthocyanin-protein complexes used in food matrices, and changes in the bioaccessibility and bioavailability of anthocyanins when bound into anthocyanin-protein complexes in foods. Finally, we summarize the challenges and prospects of this delivery system for anthocyanin pigments.

Anthocyanins: Metabolic Digestion, Bioavailability, Therapeutic Effects, Current Pharmaceutical/Industrial Use, and Innovation Potential

In this work, various concepts and features of anthocyanins have been comprehensively reviewed, taking the benefits of the scientific publications released mainly within the last five years. Within the paper, common topics such as anthocyanin chemistry and occurrence, including the biosynthesis of anthocyanins emphasizing the anthocyanin formation pathway, anthocyanin chemistry, and factors influencing the anthocyanins' stability, are covered in detail. By evaluating the recent in vitro and human experimental studies on the absorption and bioavailability of anthocyanins present in typical food and beverages, this review elucidates the significant variations in biokinetic parameters based on the model, anthocyanin source, and dose, allowing us to make basic assumptions about their bioavailability. Additionally, special attention is paid to other topics, such as the therapeutic effects of anthocyanins. Reviewing the recent in vitro, in vivo, and epidemiological studies on the therapeutic potential of anthocyanins against various diseases permits a demonstration of the promising efficacy of different anthocyanin sources at various levels, including the neuroprotective, cardioprotective, antidiabetic, antiobesity, and anticancer effects. Additionally, the studies on using plant-based anthocyanins as coloring food mediums are extensively investigated in this paper, revealing the successful use of anthocyanins in coloring various products, such as dietary and bakery products, mixes, juices, candies, beverages, ice cream, and jams. Lastly, the successful application of anthocyanins as prebiotic ingredients, the innovation potential of anthocyanins in industry, and sustainable sources of anthocyanins, including a quantitative research literature and database analysis, is performed.

Advances in dietary proteins binding with co-existed anthocyanins in foods: Driving forces, structure-affinity relationship, and functional and nutritional properties

Anthocyanins, which are the labile flavonoid pigments widely distributed in many fruits, vegetables, cereal grains, and flowers, are receiving intensive interest for their potential health benefits. Proteins are important food components from abundant sources and present high binding affinity for small dietary compounds, e.g., anthocyanins. Protein-anthocyanin interactions might occur during food processing, ingestion, digestion, and bioutilization, leading to significant changes in the structure and properties of proteins and anthocyanins. Current knowledge of protein-anthocyanin interactions and their contributions to functions and bioactivities of anthocyanin-containing foods were reviewed. Binding characterization of dietary protein-anthocyanins complexes is outlined. Advances in understanding the structure-affinity relationship of dietary protein-anthocyanin interaction are critically discussed. The associated properties of protein-anthocyanin complexes are considered in an evaluation of functional and nutritional values.

Variability in the Beneficial Effects of Phenolic Compounds: A Review

When analysing the beneficial effects of phenolic compounds, several factors that exert a clear influence should be taken into account. The content of phenolic compounds in foods is highly variable, directly affecting individual dietary intake. Once ingested, these compounds have a greater or lesser bioaccessibility, defined as the amount available for absorption in the intestine after digestion, and a certain bioavailability, defined as the proportion of the molecule that is available after digestion, absorption and metabolism. Among the external factors that modify the content of phenolic compounds in food are the variety, the cultivation technique and the climate. Regarding functional foods, it is important to take into account the role of the selected food matrix, such as dairy matrices, liquid or solid matrices. It is also essential to consider the interactions between phenolic compounds as well as the interplay that occurs between these and several other components of the diet (macro- and micronutrients) at absorption, metabolism and mechanism of action levels. Furthermore, there is a great inter-individual variability in terms of phase II metabolism of these compounds, composition of the microbiota, and metabolic state or metabotype to which the subject belongs. All these factors introduce variability in the responses observed after ingestion of foods or nutraceuticals containing phenolic compounds.