The effects of mulberry polyphenols on the digestibility and absorption properties of pork myofibrillar protein in vitro

The fermentation of whey protein and mulberry polyphenols by forming protein-phenolic adducts: Improved digestions

The impacts of forming adduct between whey protein (WP) and mulberry polyphenol (MP) on the digestion and fermentation of WP and MP were investigated using an in vitro model. The results showed that MP increased the in vitro antioxidant capacity of WP digestive products. After forming adduct the total extractable phenolic content of MP dropped from 440.20 mg GAE/g to 21.53 mg GAE/g. The total extractable phenolic content of WP-MP group decreased from 21.53 mg GAE/g to 11.77 mg GAE/g after the oral digestion, then slightly increased to 12.43 after the gastric digestion and continuously increased to 20.43 mg GAE/g after the intestinal digestion. Extractable individual phenolic compounts exhibited the similar tendency, in which cyanidin-3-O-glucoside, cyanidin-3-O-rutinoside, p-coumaric acid, quercetin and kaempferol were still detectable while protocatechuic and neochlorogenic acid increased after intestinal digestion of WP-MP adduct. Incorporation of MP inhibited the oral and gastric digestion but enhanced the intestinal digestion of WP, and the degree of hydrolysis of WP increased 9.70% after intestinal digestion compared to the control. The fermentation of non-dialyzable residue of WP-MP by gut flora decreased the pH value from 7.18 to 4.82 and increased the proliferation of beneficial bacteria and the production of short-chain fatty acids. These findings indicated that WP-MP adduct increased the digestion of WP and the bioaccessibility of MP, could improve the intestinal health and could be used as a new healthy food ingredient.

Effect of cooking treatment on protein digestibility, peptide profile and potential bioactive peptides of beef tripe during in vitro gastrointestinal digestion

The purpose of this study was to understand the effects of cooking treatment on the protein hydrolysis of beef tripe and the release of potentially bioactive peptides using an in vitro gastrointestinal model. The results showed that digestion promoted the hydrolysis of proteins and release of free amino acids in beef tripe, but cooking treatment significantly reduced them. The sample of the cooked beef tripe after gastrointestinal digestion had the highest antioxidant activity. Peptidomic and in silico analyses of gastrointestinal digesta were performed to identify bioactive antioxidant peptide sequences. A total of 14 peptides were identified, which were confirmed with structural characteristics to exhibit antioxidation effects as well as a range of other biological functions, such as angiotensin I-converting enzyme (ACE) and dipeptidyl peptidase IV (DPP-IV) inhibitory activities. These findings indicate that beef tripe and its digestive products have health-promoting potential, which can be utilized in functional food as ingredients.

Sea buckthorn polyphenols on gastrointestinal health and the interactions with gut microbiota

The potential health benefits of sea buckthorn polyphenols (SBP) have been extensively studied, attracting increasing attention from researchers. This paper reviews the composition of SBP, the effects of processing on SBP, its interactions with nutrients, and its protective role in the gastrointestinal tract. Polyphenols influence nutrient absorption and metabolism by regulating the intestinal flora, thereby enhancing bioavailability, protecting the gastrointestinal tract, and altering nutrient structures. Additionally, polyphenols exhibit anti-inflammatory and immunomodulatory effects, promoting intestinal health. The interaction between polyphenols and intestinal flora plays a significant role in gastrointestinal health, supporting the composition and diversity of the gut microbiota. However, further research is needed to emphasize the importance of human trials and to explore the intricate relationship between SBP and gut microbiota, as these insights are crucial for understanding the mechanisms underlying SBP's benefits for the gastrointestinal tract (GIT).

Mechanism of Toona sinensis seed polyphenols inhibiting oxidation and modifying physicochemical and gel properties of pork myofibrillar protein under oxidation system

This research aimed to elucidate how Toona sinensis seed polyphenols (TSSs) inhibited pork myofibrillar protein (MP) oxidation and modified physicochemical and gel properties in the Fenton oxidation system. Our result displayed that TSSs had a lower carbonyl (from 1.38 to 0.59 nmol/mg) and dityrosine contents (from 47.22 to 25.07), and higher free amino content (from 386.99 to 485.00 nmol/mg), followed by ellagic acid (EA) and quercetin-3-O-rhamnoside (QC). Meanwhile, the incorporation of phenolic compounds changed secondary and tertiary structure of proteins and then increased solubility and absolute value of zeta potential, as well as decreased turbidity and average particle size. Molecular docking indicated that MP interacted with EA primarily via hydrogen bonds and hydrophobic interaction, and with QC mostly through hydrogen bonds and electrostatic interaction. Otherwise, the incorporation of EA promoted MP gel to form a honeycomb-like microstructure after oxidation. Therefore, TSSs, EA, and QC could significantly inhibit MP oxidation as well as modify its physicochemical properties, but only EA enhanced its gel properties after oxidation. The results could be useful to improve the comprehensive utilization of plant by-products and provide theoretical references for the role of TSSs in the improvement of meat products.

Recent Advances, Challenges, and Functional Applications of Natural Phenolic Compounds in the Meat Products Industry

Natural phenolic compounds (NPCs) have been proven to effectively extend the storage time of meat products in recent years. To promote the discovery of more NPCs and their applications, this review examines recent progress in the classification, antioxidant, and antibacterial mechanisms of NPCs used in meat products. These compounds are found in both edible and inedible parts of plants, including fruits, vegetables, and trees. The recycling of agricultural by-products aligns with green agricultural trends and serves as a guideline for developing new sources of natural additives. Studies on the application of NPCs in various livestock and poultry products, either directly mixed into the matrix or indirectly contacted by preparation into bioactive films and packaging materials, has highlighted the great potential of NPCs. The pro-oxidative effects of NPCs on proteins and their interactions with biological macromolecules, such as proteins, provide new ideas for in-depth research on antioxidant and antibacterial mechanisms.

Effects of chrysanthemum extract on physicochemical, sensory, and in vitro digestion of set-type yogurt

Chrysanthemum (Chrysanthemum morifolium Ramat) contains multiple bioactive substances and presents health benefits. In this study, a chrysanthemum extract (CE) was prepared by heat reflux extraction method and a functional yogurt was fabricated containing CE. According to the results of UPLC-MS/MS, 6 phenolic acids and 13 flavonoids were identified from CE compounds. The physicochemical and functional properties of yogurt during storage were investigated. In addition, rheology, microstructure and simulated digestion of yogurt on Day 1 were analyzed. The results demonstrated that the value of pH, total phenolic and flavonoid content, antioxidant capacity, the polyphenols stability in vitro gastric and intestinal digestion condition in the yogurt were enhanced. The syneresis, titratable acidity and the rate of protein hydrolysis in vitro gastric and intestinal digestion condition in the yogurt were reduced with CE addition. Moreover, the changes of protein network and sensory characteristics of yogurt were also occurred with addition of CE. These findings suggest that the integration of CE with yogurt is a promising way to improve the quality and storage ability of yogurt.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-06000-5.

Encapsulation and release of salidroside in myofibrillar protein‑sodium alginate gel: Effects of different M/G ratios of sodium alginate

Myofibrillar protein‑sodium alginate (MP-SA) gels play a pivotal role in the development of functional food gels. Salidroside (SAL) is promising component but suffers from low bioavailability, necessitating effective delivery systems. This study introduces M/G ratio factor into classical theoretical MP-based gel models, and use for the SAL delivery. The findings indicate that SA significantly enhances gel properties and functions. Scanning electron microscopy, liquid chromatography, and low-field nuclear magnetic resonance confirmed that the addition of SA improved microstructure, water retention, and thus reduced SAL loss during processing. Digestion simulations revealed the influence of SA type on SAL release kinetics. Molecular docking showed that SA with lower M/G ratio binds more readily to MP, a key determinant of gel performance. These insights provide a novel theoretical basis for MP-SA gels and offer a new perspective on the delivery of bioactive compounds in functional foods.

Precise evaluation of batch adsorption kinetics of plant total polyphenols based on a flow-injection online spectrophotometric method

Efficient evaluation of adsorption kinetics of plant total polyphenols is essential for the design of adsorption separation of bioactive compounds. The conventional method uses manual sampling with poor reproducibility. Here, we developed a new method for on-line determination of total polyphenol content (TPC) in plant extracts by applying the Folin-Ciocalteu method in flow-injection analysis (FIA). The FIA parameters were optimized and a standard curve with excellent linearity was established. Precise determination of TPC with a satisfactory sample throughput of 20 h-1 was achieved for the adsorption kinetic study. The pseudo-second-order kinetic model was found to better describe the kinetic parameters of the batch adsorption/desorption process. The developed method proved to be accurate compared with the conventional method. The FIA method holds significant promise for studying and monitoring adsorption processes, due to its automatic on-line nature, low consumption of reagents and samples, and the ability to generate large quantities of highly accurate adsorption data.

Whole Flour of Purple Maize as a Functional Ingredient of Gluten-Free Bread: Effect of In Vitro Digestion on Starch and Bioaccessibility of Bioactive Compounds

The growing demand for gluten-free products requires the study of alternatives to produce nutritionally and technologically favorable foods. The aim was to evaluate the content and antioxidant capacity of gluten-free bread enriched with whole flour of purple maize (PM) and how starch and bioaccessibility of antioxidant compounds were modified during in vitro digestion. Gluten-free bread was prepared with the addition of 34%, 50%, and 70% PM, and white maize bread served as control. The content of total polyphenols, anthocyanins, and antioxidant capacity through FRAP and TEAC was measured. Specific volume, crumb texture, and starch digestibility were determined in the breads. Simultaneously, in vitro digestion and dialysis by membrane were performed to evaluate the bioaccessible and potentially bioavailable fraction. Bread with 34% PM had a similar specific volume and crumb texture to the control, but higher content of polyphenols (52.91 mg AG/100 g), anthocyanins (23.13 mg c3-GE/100 g), and antioxidant capacity (3.55 and 5.12 µmol tr/g for FRAP and TEAC, respectively). The PM breads had a higher antioxidant content and capacity and higher slowly digestible and resistant starch than the control. These parameters increased as the PM proportion rose. After digestion, anthocyanins were degraded, polyphenols and antioxidant capacity decreased, but they remained potentially bioavailable, although to a lesser extent. Bread with 34% shows acceptable technological parameters, lower starch digestibility, and contribution of bioactive compounds with antioxidant capacity. This indicates that purple maize flour represents a potential ingredient to produce gluten-free bread with an improved nutritional profile.