A standardised static in vitro digestion method suitable for food - an international consensus

Maillard reaction products in plant-based dairy alternatives and their release during simulated gastrointestinal digestion

Plant-based food products are becoming increasingly popular among consumers. The chemical composition and the processing of plant-based products presumably fuel the Maillard reaction, but the abundance of Maillard reaction products in plant-based food products is rarely investigated. In this study, the concentration of N-ε-carboxymethyllysine (CML), N-ε-carboxyethyllysine (CEL) and methylglyoxal-hydroimidazolone (MG-H1) was analyzed with UPLC-MS/MS in six plant-based dairy alternatives. Total amounts of free and protein-bound glycation compounds ranged from 0.03 to 0.31 mg/100 g food for CML, 0.04-1.28 mg/100 g food for CEL and 0.69-2.84 mg/100 g food for MG-H1. Free glycation compounds were abundant in yogurt and cheese, but not milk alternatives. During simulated gastrointestinal digestion, CML and MG-H1 were released either as modified amino acid or in peptide-bound form, respectively. CEL was released to a significantly lesser extent in peptide-bound form. For CML, de novo formation of up to 400 % during digestion was observed. The results showed that Maillard reaction products are quantitatively important process-induced compounds in plant-based food products which are available after digestion.

Protein-added kefir: biochemical changes in in vitro digestion stages

BACKGROUND

While yogurt is the leading fermented milk product, kefir is at the top of the beverage scale. Milk proteins, on the other hand, show specific functions that positively affect healthy nutrition due to the bioactive components, that they provide the necessary amino acids for growth and development.

RESULTS

In our study, kefir, a functional product enriched with whey proteins, casein and skimmed milk powder, which are the natural components of milk, was produced. Added-protein kefir samples were applied the in vitro digestion protocol, static method. In order to observe different protein behaviors, samples were taken pre-digestion, at 120th minute and at 240th minute of digestion protocol. ACE and Antioxidant capacity determination analyzes were carried out. While ACE inhibition values were in the range of 78.63-90.30% pre-digestion, they changed in the range of 86.97-96.38% after gastrointestinal digestion. It was determined that the ACE inhibition values of the control sample remained at the lowest level at all stages of digestion and that the difference between all of samples was significant (P < 0.05). Antioxidant activity value ranging from 0.3615-0.5512 meq Ascorbic acid/μg before digestion was determined as 1.3796-1.9313 meq Ascorbic acid/μg after gastrointestinal digestion (P < 0.05).

CONCLUSION

Kefir samples containing whey protein stand out with their high potential in terms of both antioxidant activity capacity and ACE inhibition activity at all stages of digestion. Considering their therapeutic effects in fermented products, it is thought that whey proteins among milk proteins will be important alternative sources to enrich the protein content in kefir production. © 2024 Society of Chemical Industry.

A Non-Pharmacological Paradigm Captures the Complexity in the Mechanism of Action of Poliprotect Against Gastroesophageal Reflux Disease and Dyspepsia

When the protective mechanisms of the gastroesophageal mucosa are overwhelmed by injurious factors, the structural and functional mucosal integrity is compromised, resulting in a wide spectrum of disorders. Poliprotect has recently been shown to be non-inferior to standard-dose omeprazole for the treatment of endoscopy-negative patients with heartburn and/or epigastric pain or burning. Here, we provide preclinical data describing the mechanism of action of the Poliprotect formulation, a 100% natural, biodegradable, and environmental friendly medical device according to EU 2017/745 and containing UVCB (unknown or variable composition, complex-reaction products, or biological materials) substances of botanical and mineral origin, according to the REACH and European Chemical Agency definitions. Different in vitro assays demonstrated the capability of Poliprotect to adhere to mucus-secreting gastric cells and concomitantly deliver a local barrier with buffering and antioxidant activity. In studies conducted in accordance with systems biology principles, we evaluated the effects of this barrier on human gastric cells exposed to acidic stress. Biological functions identified via Ingenuity Pathway Analysis highlighted the product's ability to create a microenvironment that supports the mucosal structural and functional integrity, promotes healing, and restores a balanced mucosal inflammatory status. Additionally, transepithelial electrical resistance and an Ussing chamber showed the product's capability of preserving the integrity of the gastric and esophageal epithelial barriers when exposed to an acid solution. Two in vivo models of erosive gastropathy further highlighted its topical protection against ethanol- and drug-induced mucosal injury. Overall, our findings sustain the feasibility of a paradigm shift in therapeutics R&D by depicting a very innovative and desirable mode of interaction with the human body based on the emerging biophysical, rather than the pharmacological properties of these therapeutic agents.

Novel Fermented Plant-Based Functional Beverage: Biological Potential and Impact on the Human Gut Microbiota

Controlled fermentation carried out by selected starters might enhance the safety, nutritional, and biological profiles of non-dairy fermented products. This research aims to study the biological potential and impact on the human gut microbiota of a novel fermented finger millet-based product. Finger millet (Eleusine coracana), suspended in an aqueous sucrose-based solution, was fermented by Weissella confusa 2LABPT05 and Lactiplantibacillus plantarum 299v (1%, 1:1 ratio (v/v)), at 30 °C/200 rpm in an orbital incubator until pH ≈ 4.5-5.0. Microbial growth, phenolic compounds, antioxidant, and antidiabetic activities were evaluated. In vitro digestion followed by in vitro faecal fermentation were used to study the impact of the fermented plant-based functional beverage (PBFB) on the human gut microbiota. Antidiabetic activity (21% vs. 14%) and total phenolics (244 vs. 181 mg of gallic acid equivalents/kg PBFB) increased with fermentation. The digested fermented PBFB contributed to the increase, over the first 6 h, of the Bifidobacterium's 16S rRNA gene copy numbers, concomitant with significant release of the acetic, propionic, and butyric short chain fatty acids, and also lactic acid. The novel PBFB has been shown to have antidiabetic potential and bifidogenic effects, and consequently its consumption might positively impact blood glucose levels and the human gut microbiota.

Current State of Research on Health-Promoting Functional Properties in Berry-Based Foods

PURPOSE OF REVIEW

This review aims to consolidate recent findings on the development and functional validation of berry-based foods while proposing guidelines for future advancements.

RECENT FINDINGS

Current investigations on berry-based functional foods (dairy and bakery products, snacks, etc.) emphasize their potential health benefits, including antioxidant effects, glycemic control, enzyme modulation, among others. Although there is valuable information on the capacity of berry-derived food products to confer health benefits, only 10% of the reviewed publications reached the final validation stage of the formulated product through in vivo assays. The analyzed publications were classified according to the approach used to study the functional potential of the developed berry-based products, considering simple spectrophotometric analysis, in vitro biological studies, and in vivo studies. Guidelines for a successful development of berry-based health enhancing foods were presented. Future research should include functional validation of final food products and confirm their bioactivity through in vivo studies.

Zinc absorption from maize-based meals enriched with edible house crickets: a randomized crossover stable-isotope study in Kenyan pre-school children

Edible insects have been proposed as a novel and sustainable source of protein and other essential nutrients for human consumption but nutrient absorption efficiency is still uncertain. We investigated zinc absorption from house crickets (Acheta domesticus) in a single-center and single-blinded cross-over study with children aged 24-36 months old in Kenya from September-November 2021. For this, children were randomized to consume two different experimental meals labeled with stable isotopes of zinc (Zn) at two different days, separated by a wash-out period of one month. Primary endpoints were the differences in amount of absorbed zinc (AZ) from maize-based meals enriched with intrinsically 67Zn-labeled house crickets (2.61 mg Zn, n = 28) in comparison with meals enriched with 68Zn (low-enriched: 0.90 mg Zn, n = 29); high-enriched: 3.24 mg Zn, n = 28) or with intrinsically 67Zn-labeled low-chitin cricket flour (2.51 mg Zn, n = 25), whereas the secondary endpoints were the differences in fractional zinc absorption. We found that AZ from meals with whole crickets (geometric mean: 0.36 mg; 95%CI: 0.30, 0.43) was 2.6 times higher than from low-enriched maize meals (0.14 mg; 0.11, 0.16; P < 0.001), while it was not different from low-chitin cricket flour meals. Absorbed zinc from both cricket meals was higher than that from high-enriched meals. No severe adverse side events were reported. We conclude that edible house crickets are a good source of well-absorbable zinc, and their increased consumption could contribute to the alleviation of zinc deficiency. This trial was registered at the Pan African Clinical Trials Registry as PACTR202104533831364.

A legume-enriched diet improves metabolic health in prediabetes mediated through gut microbiome: a randomized controlled trial

Healthy dietary patterns rich in legumes can improve metabolic health, although their additional benefits in conjunction with calorie restriction have not been well-established. We investigated effects of a calorie-restricted, legume-enriched, multicomponent intervention diet compared with a calorie-restricted control diet in 127 Chinese prediabetes participants, living in Singapore. The study was a 16-week, single-blind, parallel-design, randomized controlled trial (n = 63 intervention group (IG), n = 64 control group (CG); mean ± SD age 62.2 ± 6.3 years, BMI 23.8 ± 2.6 kg/m2). Primary outcomes were markers of glycemia and all measurements were taken at 2 or 4-weekly intervals. At the end of 16 weeks, both groups had significantly lower BMI (q(Time) = 1.92 ×10-42, β  = -0.02) compared with baseline, with minimal difference between groups. The IG had significantly greater reductions in LDL cholesterol (q(Treatment×Time) = 0.01, β  = -0.16), total cholesterol (q(Treatment×Time) = 0.02, β  = -0.3) and HbA1c (q(Treatment×Time) = 0.04, β  = -0.004) compared with CG, alongside increases in fiber degrading species in IG, mediated through metabolites such as bile acids and amino acids. A legume-enriched, multicomponent intervention diet can improve metabolic health in a prediabetes population, in addition to benefits obtained from calorie restriction alone, partially mediated through changes in gut microbial composition and function. Trial registration: Clinical Trials NCT04745702.

Functional Plant-Based Beverage Fortified with Hazelnut Cuticle Polyphenols: Antioxidant and Phenolic Content Characterization

In recent decades, there has been growing interest in the fortification of food products with antioxidants and phenolics derived from plant by-products. The present study focused on the production of a plant-based beverage enriched with hazelnut cuticle extract to characterize its antioxidant content, phenolic profile, and organoleptic characteristics. Liquid chromatography-mass spectrometry (LC-MS) enabled the identification of key polyphenols in hazelnut cuticles, including catechin, epicatechin, and quercetin derivatives, guiding the selection of a biocompatible Natural Deep Eutectic Solvent (NADES) composed of choline chloride and lactic acid for efficient extraction. The obtained phytochemical profile of the extract revealed a high concentration of bioactive compounds, with a Total Phenolic Content of 160.88 ± 14.27 mg GAE/g and Antioxidant Power measured by DPPH of 5848.2 ± 11.3 μmol TE/g. The bioaccessibility of phenolics in the fortified hazelnut-based beverage was determined after in vitro digestion, reaching a value of 89.7%, indicating excellent release and stability during digestion. Organoleptic evaluation revealed high sensory acceptability, with aftertaste scoring 3.61 ± 0.4 respect the 3.94 ± 1.3 result of reference milk, on a 5-point scale. In conclusion, this study demonstrates the potential for sustainable valorization of hazelnut cuticles, through their incorporation as NADES extracts in plant-based milk, providing an innovative solution to reduce food waste while catering to consumer demand for nutritionally enriched and eco-friendly products.

2'-Fucosyllactose as a prebiotic modulates the probiotic responses of Bifidobacterium bifidum

2'-Fucosyllactose (2'-FL), one of the most representative oligosaccharides in human milk, is intimately linked to the enrichment of specific Bifidobacterium species. However, the efficacy of 2'-FL in modulating the probiotic responses of bifidobacterium has been rarely researched. Thereinto, three key issues have yet to be reported: the effects of 2'-FL hydrolysis on bifidobacterial growth, the protective effects of 2'-FL on bifidobacterium under gastrointestinal stress and the inhibitory activity of 2'-FL metabolites against Cronobacter spp. This work intended to address these concerns. 2'-FL dramatically accelerated the growth and proliferation of Bifidobacterium bifidum YH17 and Bifidobacterium bifidum BBI01. The glucose in lactose core on 2'-FL was preferable for B. bifidum to achieve substantial increases in biomass while the galactose was not readily available. Additionally, 2'-FL showed unique advantages in ameliorating the resistance of B. bifidum to gastrointestinal challenges. 2'-FL considerably improved the adhesive property of B. bifidum, thus facilitating the competitive elimination of Cronobacter sakazakii ATCC 29544 and Cronobacter muytjensii ATCC 51329 by B. bifidum. The growth inhibition of 2'-FL on the Cronobacter strains was mediated by promoting the secretion of antibacterial substances from B. bifidum. The inhibitory activity hinged on the B. bifidum strains. 2'-FL specifically induced B. bifidum BBI01 to produce some antibacterial substances that were proteinaceous, thermostable and relatively stable even at pH 8.0. These antibacterial substances played a key role in the inhibitory activity and had a synergistic effect with acidification. These observations provide a useful guideline for developing synbiotic supplements to intervene the infant gut microbiota.

Betalain-Chickpea Protein Particles Produced by Freeze Drying and Spray Drying: Physicochemical Aspects, Storage Stability, and In Vitro Digestion

Beetroots are one of the primary sources of betalains, nitrogenous pigments with anti-inflammatory and antioxidant properties. However, due to their chemical instability, betalains have limited use in food applications. This work investigated whether betalains encapsulated in chickpea protein could be stabilized and delivered in a shelf-stable format. Freeze-dried (CB-FD) and spray-dried (CB-SD) protein-betalain particles encapsulated in chickpea protein isolate (6% w/v) were prepared. The encapsulation method affected particles' morphology, water activity, hygroscopicity, solubility, and color. Particles captured total betalains of 9.30 ± 0.61 and 4.40 ± 0.92 mg/g for CB-SD and CB-FD, respectively. LC-MS identified 12 betacyanins and 6 betaxanthins. The stability of betalains revealed that encapsulation efficiently preserved betalain integrity of over 6 weeks of storage at 4, 22, and 40 °C compared to dry beetroot extract. CB-SD particles were stable with no significant changes, while CB-FD showed slight degradation after 4 weeks due to increased Aw. Antioxidant activity correlated well with betalain concentration. In vitro digestion resulted in only 25% bioaccessibility of betacyanins, while betaxanthins were more stable with 100% recovery. Encapsulation with chickpea protein isolate is an efficient and straightforward strategy for expanding and diversifying applications of phytochemical-rich beetroot extracts for the food industry.

Effect of NaCl on the structure and digestive properties of heat-treated myofibrillar proteins

During meat processing, the quality of food and structure of meat proteins are affected by different processing technologies and addition of raw and auxiliary materials. Different meat products are treated with varying processing temperatures and NaCl content, changing the protein molecular structure. This study aimed to determine impact of heating temperature (40-115 °C) and NaCl concentration (0-0.8 M) on the oxidation, structure, and digestibility of beef myofibrillar proteins. The results revealed that high temperatures and NaCl concentration of 0.4-0.8 M caused the salting-out effect, leading to a decrease in solubility. The oxidative denaturation of proteins leads to increased protein aggregation. Consequently, structural changes of myofibrillar proteins, and the digestive enzymes are unable to recognize specific sites, which reduces the digestibility of the proteins. The findings of this study revealed that heating beef myofibrillar proteins at 85 °C and 0.4 M NaCl substantially improved its digestibility to 85.66 %.

The complex coacervation of gum Arabic and krill protein isolate and their application for Antarctic krill oil encapsulation

Antarctic krill oil (AKO) possesses potent bioactivities but has limited applications in the food industry due to its poor stability, strong off-flavor, and low bioavailability of contained astaxanthin. In this study, Antarctic krill protein isolate (AKPI) was separated from processing by-product of krill and utilized as a novel wall material via complexing it with gum Arabic (GA) to improve the limitations of AKO. The strong complex coacervation reaction between AKPI and GA was occurred at the pH of 3.8 and the ratioAKPI-to-GA of 3:1, while electrostatic interaction and hydrogen-bond interaction were determined to be the main driving forces of such reaction. The ratiowall-to-core was confirmed as 1:0.75 after comprehensively assessing the effect of AKO content on the various properties of AKPI-GA coacervated microcapsules, while the wall material concentration and pH were optimized at 1 % and 3.8, respectively. The obtained solid AKO microcapsules exhibited the encapsulation efficiency of 80.22 %. AKPI-GA coacervated microcapsules extremely masked the odor of AKO and achieved the controlled-release of AKO in the gastrointestinal tract. Meanwhile, the encapsulated AKO displayed higher astaxanthin retention and oxidative stability compared with non-encapsulated AKO during storage.

Pectin-chitosan hydrogels with modified properties for the encapsulation of strawberry phenolic compounds

Pectin-chitosan hydrogels with blends of low (50-190 kDa) and medium (310-395 KDa) molecular weight (MW) chitosan (LC and MC, respectively) were developed, and their characteristics were investigated before and after the encapsulation of an aqueous strawberry extract. The pectin to total chitosan mass ratio, the composition of the strawberry extract and the MW of chitosan greatly affected the interactions between pectin and chitosan at different pH values. More specifically, blends of low and medium MW chitosan improved the stability of the strawberry-gels in acidic conditions compared to their corresponding MC-gels, showed better flow and texture profiles, as well as slower release of phenolic compounds during in vitro digestion compared to the only stable LC-gel. Therefore, by manipulating the length range of chitosan chains would allow the formation of pectin-chitosan hydrogels with improved properties for the development of functional food products.

Unlocking the potential of fermented beetroot ketchup: Enhancing polyphenol recovery and gut microbiota interactions

The study aimed to evaluate the effect of digestion and gut microbiota interactions on beetroot ketchup formulations, focusing on the release of polyphenols, bioaccessibility, and microbial interactions on gut microbiota with polyphenols. Tested ketchup samples were evaluated using the TNO Gastro-Intestinal Model 1 (TIM-1) simulated upper part of the gastrointestinal tract and the TNO Gastro-Intestinal Model 2 (TIM-2) simulated colon system. The results showed that fermentation of ketchup with Lactobacillus johnsonii K4, increased the release of bioactive compounds during digestion, with higher polyphenol recoveries observed in fermented samples. In particular, a fermented sample has higher recovery percentages for most of the phenolic acids, flavonoids, and betalains. However, some polyphenolic compounds were degraded during fermentation, suggesting a dynamic process of polyphenol metabolism in the gut environment. The study highlights the potential of fermented foods, such as beetroot ketchup, enriched with polyphenols and beneficial bacteria, to promote gut health and overall well-being.

Bioaccessibility of avocado polyhydroxylated fatty alcohols

Avocado-derived polyhydroxylated fatty alcohols (PFAs), such as avocadene and avocadyne, have been recently identified as potent modulators of mitochondrial metabolism which selectively induce leukemia cell death and reverse pathologies associated with diet-induced obesity. However, avocadene and avocadyne bioaccessibility from avocado pulp is not reported; hence, this study aims to investigate if these PFAs are bioaccessible. Dynamic (TNO dynamic intestinal model-1 (TIM-1)) and static in vitro digestion of lyophilized Hass avocado pulp powder shows lipolytic gastrointestinal enzymes led to appreciable bioaccessibility of avocadene (55%) and avocadyne (50%). Furthermore, TIM-1 digestion of a 1:1 ratio of pure avocadene and avocadyne (avocatin B or AvoB) crystals formulated in an oil-in-water microemulsion has on average 15% higher bioaccessibility than the avocado pulp powder demonstrating both dosage forms as potential dietary sources of avocado PFAs. This research provides the impetus for further research on the nutritional significance of dietary long chain fatty alcohols.

Enhanced protection and bioavailability of Lycium barbarum leaf extract through encapsulation in whey protein isolate and bovine serum albumin nanoparticles

To improve the stability and bioavailabilityhe of polyphenolics in Lycium barbarum leaf, this study encapsulated L. barbarum leaf extracts (LLE) within whey protein isolate (WPI) and bovine serum albumin (BSA) nanoparticles (NPs) via self-assembly to enhance polyphenol distribution. The physicochemical properties of nanoparticles were characterized using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermogravimetric (TG), respectively. The nanoparticles also showed good physical stability at various temperatures, different pH and NaCl concentrations. Compared with BSA-LLE NPs, WPI-LLE NPs exhibited strong physical stability with encapsulation efficiency of 70.6 %. The polyphenol nanoparticles demonstrated enhanced stability in the presence of stomach acid during in vitro simulated digestion. Additionally, the nanoparticles enhanced polyphenol stability during simulated gastrointestinal digestion. Following intestinal digestion, compared with LLE, the bioaccessibility of total phenolic increased by 53.67 % (WPI-LLE NPs), with specific enhancement in compounds like kaempferol, rutin, and chlorogenic acid.

Study on gastric digestion behavior of phytase-treated soybean protein: A semi-dynamic digestion method

The digestive characteristics of plant proteins are crucial for their nutritional value and utilization efficiency. In this study, an in vitro semi-dynamic digestion model was employed to investigate the gastric digestion process of soybean protein after treatment with phytase. The results found that phytase treatment reduced the phytate content in soybean proteins (22.83 ± 0.09 to 8.72 ± 0.07 mg/g), shifted its isoelectric point towards the alkaline range by 1 pH unit, and significantly improved its solubility at pH 4.0. Particularly for protein sample treated with phytase after acid precipitation, the formation of aggregates during digestion was weakened, resulting in a significantly higher digestion rate compared to untreated SPI, with digestion being at least 15 min faster than SPI. This study provides a strategy for preparing soybean protein with faster digestion and weaker clot-forming ability during digestion, which offers insights for the application of soybean protein in clinical nutrition products and specialized medical foods.

Effect of inulin on structural, physicochemical, and in vitro gastrointestinal tract release properties of core-shell hydrogel beads as a delivery system for vitamin B12

In this study, core-shell hydrogel beads were developed as a controlled-release delivery system for vitamin B12. Vitamin B12-loaded microgels (MG) were prepared using gellan gum (GG). Core-shell hydrogel beads were produced by incorporating MG into pea protein isolate (PPI) and sodium alginate (AL) matrix filled/coated with different concentrations (0 %, 1 %, 3 %, 5 %, and 10 %) of inulin (IN). Based on XRD analysis, MG was successfully incorporated into core-shell hydrogel beads. In FE-SEM and FT-IR analyses, the smoother surface and denser structure of the beads were observed as IN concentration increased due to hydrogen bonds between IN and the beads. The encapsulation efficiency increased from 68.64 % to 82.36 % as IN concentration increased from 0 % to 10 %, respectively. After exposure to simulated oral and gastric conditions, core-shell hydrogel beads exhibited a lower cumulative release than MG, and a more sustained release was observed as IN concentration increased in simulated intestinal conditions.

Oil/water interface behavior of hesperidin methylchalcone and its application in nano-emulsions

The behavior of hesperidin methylchalcone (HMC) at the oil/water interface was examined through experimental and molecular simulation methods, and a nano-emulsions based on HMC was subsequently fabricated. The findings indicated that HMC spontaneously aggregated at the oil-water interface, leading to a reduction in interfacial tension and an increase in interfacial thickness. Furthermore, its glycoside and benzene ring showed tendencies to interact with water and medium-chain triglyceride, respectively. The HMC addition amount (w), homogenization times (n) and homogenization pressure (p) significantly influenced the formation of the nano-emulsions. The nano-emulsion with an oil-droplet size of 277.26 ± 13.62 nm was obtained at w = 1.0 %, p = 200 bar, and n = 6. When compared to the Tween 20 nano-emulsion, the HMC nano-emulsion demonstrated superior storage stability, antioxidant activity, and lutein bioaccessibility. It could achieve the slow release of HMC. These findings not only broaden the application range of HMC but also contribute to the advancement of functional nano-emulsions.

Effect of Pre-Emulsified Flaxseed Oil Containing Rutin on the Quality of Nemipterus virgatus Surimi Gel: Gelatinization Properties, Storage Stability, and Protein Digestibility

Rinsing during surimi protein processing can result in the loss of essential nutrients, such as fats and minerals. Therefore, supplementing functional fats in a stable form can make up for the fat loss of surimi during the rinsing process. This research aimed to investigate the effects of incorporating pre-emulsified flaxseed oil with different concentrations of rutin (0, 0.5, 1.5, 2.5, and 3.5%, dissolved in flaxseed oil, w/v) to Nemipterus virgatus surimi on the gelatinization properties, lipid oxidation, and in vitro static simulated digestion characteristics of surimi gels. The results indicated that the addition of 1.5% rutin significantly improved the water-holding capacity and decreased the cooking loss rate of surimi gel (p < 0.05). The results of optical microscopy and scanning electron microscopy showed that the addition of 1.5% rutin promoted a denser network structure of surimi gel. Furthermore, the incorporation of rutin effectively slowed lipid oxidation in pre-emulsified flaxseed oil surimi gel. Compared with the gel group containing only pre-emulsified flaxseed oil, the addition of rutin significantly reduced the levels of volatile base nitrogen (TVB-N) and thiobarbituric acid reactive substances (TBARSs) in the gel and also mitigated the decline in acidity (p < 0.05). Moreover, the addition of rutin significantly inhibited the decrease in pH of surimi gel during storage (p < 0.05). In vitro static simulated digestion demonstrated that the addition of 1.5% rutin enhanced the protein digestibility from 71.2% to 77.2% of the surimi gel. Therefore, adding pre-emulsified oil containing an appropriate amount of rutin to surimi can not only compensate for the fat loss during the surimi rinsing process but also effectively improve the quality characteristics of surimi gels. This research will provide a theoretical basis for the effective addition of functional lipids in surimi products and the development of nutritious and healthy surimi products.

The Effect of β-Glucan on the Release and Antiradical Activity of Phenolic Compounds from Apples in Simulated Digestion

Beneficial activities of phenolic compounds in the gastrointestinal tract, such as antiradical activity, are affected by the food matrix. The aim of this study was to investigate the influence of one constituent of the food matrix (dietary fiber β-glucan) on the release and antiradical activity of phenolic compounds from apples in gastrointestinal digestion. Simulated digestion in vitro was conducted on whole apples without or with added β-glucan. Antiradical activity was determined with the DPPH method. The total amount of released phenolic compounds in the stomach (563 mg kg-1 fresh weight (fw), 85%) decreased in the intestine (314 mg kg-1 fw, 47%) (p < 0.05). The presence of β-glucan decreased the release of phenolic compounds to 80 and 74% in the stomach and to 44 and 40% in the small intestine when there were lower and higher β-glucan amounts, respectively. A statistical analysis showed differences between release in digestion without or with β-glucan. B-glucan adsorbed up to 24 (stomach) and 32 mg g-1 (small intestine) of the phenolics. Phenolic compounds scavenged more free radicals in the small intestine than in the stomach, and β-glucan decreased this activity, but not significantly. The interaction between β-glucan and phenolic compounds should be considered when explaining the beneficial effects in the stomach and small intestine.

Physicochemical Characterization, Storage Stability Behavior, and Intestinal Bioaccessibility of Clove Extract Encapsulated Using Varying Combinations of Gum Arabic and Maltodextrin

Clove (Syzygium aromaticum, L.) is a rich source of polyphenols and antioxidants, but its intense flavor, poor solubility, and instability may limit its widespread and efficient use in industrial applications. In a series of laboratory-scale experiments, gum Arabic (GA) and maltodextrin (MD) were used as coating agents in various proportions (ranging from 0MD:100GA to 100MD:0GA) for encapsulation of clove extract using a freeze-drying method. The encapsulates were assessed for the physicochemical properties, storage stability behavior, and intestinal bioaccessibility of phenolics using an in vitro gastrointestinal digestion test. The freeze-dried encapsulates were characterized as having low water activity (<0.3, which is a critical threshold to ensure chemical and microbiological stability), high water solubility (>90%), solid (product) recovery (mean 93.1 ± 1.77%), and encapsulation efficiency (91.4-94.9%). Hygroscopicity increased as the GA:MD proportion increased in the encapsulation formulations. Encapsulation was effective in protecting bioactive components of clove extract during storage at room (up to 40 days) or high temperature (60 °C for 7 days) and minimized the loss of antioxidant activity during storage, as compared to the clove extract in a non-encapsulated form. All encapsulation formulations were characterized by a negative zeta potential (from -22.1 to -29.7 mV) and a polydispersity index ranging from 0.47 to 0.68, classifying the formulations as having a mid-range polydisperse particle size distribution. The FTIR analysis demonstrated that the freeze-drying encapsulation process resulted in no evident chemical interaction between coating and core materials. Intestinal bioaccessibility of total phenolics after the in vitro-simulated gastrointestinal digestion was greater in the encapsulated clove extract compared to the non-encapsulated clove extract. In conclusion, the encapsulation process was effective in protecting the bioactivity of the polyphenol-rich clove extract during storage and improved the phenolic bioaccessibility, potentially supporting the application of the encapsulated clove extract for use in functional food development.

Oatmeal and wheat flour as the sources of thyroid peroxidase and proinflammatory enzymes modulators in the prevention of thyroid diseases

Polyphenolic plant compounds possess nutritional and pro-healthy potential, reducing the risk of auto-inflammatory and neoplastic diseases. However, their interference with the progression of thyroid gland dysfunctions has remained largely unaddressed. For this purpose, we combined the analyses of phenolic content and antioxidative activity with the thyroid peroxidase (TPO), lipoxygenase (LOX), xanthine oxidase (XO) and cyclooxygenase-2 (COX-2) activity assays, isobolographic approach and the estimation of thyroid cancer cells' proliferation and motility in vitro. Bioaccessible oatmeal (OM) and wheat flour (WF) compounds activated TPO while inhibiting LOX and XO's in vitro activity. OM extracts also inhibited COX-2 activity. Isobolographic and combination index studies revealed cooperation of compounds from OM and WF. However, the relatively strong inhibitory activity of bioaccessible OM compounds on LOX activity correlated with their mildly cytostatic and relatively distinct pro-invasive effects in the thyroid cancer model in vitro. Collectively, the application of OM and WF products for the prophylactics of inflammatory thyroid diseases should be considered with care, especially in the context of the oncological status of the patient.

Impact of Nanoplastics on the Functional Profile of Microalgae Species Used as Food Supplements: Insights from Comparative In Vitro and Ex Vivo Digestion Studies

The widespread use of plastics in the food industry raises concerns about plastic migration and health risks. The degradation of primary polymers like polystyrene (PS) and polyethylene (PE) can generate nanoplastics (NPs), increasing food biohazard. This study assessed the impact of PS, PE, and PS + PE NPs on Chlorella vulgaris (CV) and Haematococcus pluvialis (HP) before and after in vitro and ex vivo digestion, focusing on particle size, polydispersity index, and surface charge. The modulation of total phenolic content (TPC) induced by NP contamination was also evaluated. Results demonstrated that NP behavior varied with the microalgae medium and persisted postdigestion, posing health risks. Significant size increases were noted for PS + PE in the CV and HP. TPC increased significantly with NP exposure, especially PS + PE. These findings underline the need for regulatory measures to ensure food safety in cases of plastic contamination and to address the behavior and toxicity of NPs.

Study on the Effect of Radish Sprouts on Short-Chain Fatty Acids and Gut Microbial Diversity in Healthy Individuals

This study aimed to assess the impact of radish sprouts on the gut microbiota of healthy individuals. Radish sprout additives, subjected to short-term storage and steam treatment, were used to intervene in an in vitro culture of human gut microbiota. The influence of radish sprouts on the gut microbiota was evaluated by monitoring short-chain fatty acid (SCFA) content and proportion in the fermentation broth, and microbial diversity was assessed using 16S rDNA amplicon sequencing. The results indicated that the gut microbiota produced a substantial amount of SCFA within 48 h of fermentation, with a right-skewed distribution across all groups. The addition of both digestates enhanced Firmicutes diversity, while Bacteroidetes and Proteobacteria diversity remained stable between the control and fresh sprout groups. The 30 s steam treatment group showed an increase in Bacteroidetes and a decrease in Proteobacteria diversity. The abundance of Bacilli, Bacillaceae, and Bacillus was significantly higher in both the fresh and steam-treated groups compared to the control. Both fresh and steam-treated radish sprout digestates enriched gut microbiota diversity, with steam treatment showing superior effects. These findings suggest that radish sprout consumption may positively influence gut microbiota, with steam treatment potentially enhancing these benefits.

Optimization of sulforaphane bioavailability from a glucoraphanin-rich broccoli seed extract in a model of dynamic gastric digestion and absorption by Caco-2 cell monolayers

Broccoli is recognized for its health benefits, attributed to the high concentrations of glucoraphanin (GR). GR must be hydrolyzed by myrosinase (Myr) to form the bioactive sulforaphane (SF). The primary challenge in delivering SF in the upper gastrointestinal (GI) tract- is improving hydrolysis of GR to SF. Here, we optimized the formulation and delivery methods to improve GR conversion and SF bioavailability. We investigated whether the combination of GR-rich broccoli seed extract powder (BSE[GR]) with Myr-rich mustard seed powder (MSP[Myr]), ± ascorbic acid (AA, a co-factor of Myr), delivered as free powder or encapsulated powder, can: (i) facilitate GR hydrolysis to SF during dynamic in vitro gastric digestion and static in vitro small intestinal digestion, and (ii) increase SF bioavailability in Caco-2 cell monolayers, a model of human intestinal epithelium. Addition of exogenous Myr increased the conversion of GR to SF in free powder during small intestinal digestion, but not during gastric digestion, where Myr activity was inhibited by the acidic environment. Capsule delivery of BSE[GR]/MSP[Myr] (w/w ratio 4 : 1) resulted in a 2.5-fold higher conversion efficiency compared to free powder delivery (72.1% compared to 29.3%, respectively). AA combined with MSP[Myr] further enhanced the conversion efficiency in small intestinal digestion and the bioavailability of SF in Caco-2 cell monolayers. Bioavailability of GR as SF, SF metabolites, and GR was 74.8% in Caco-2 cell monolayers following 30 min gastric digestion and 60 min small intestinal digestion. This study highlights strategies to optimize GR bioconversion in the upper GI tract leading to enhanced SF bioavailability.

Relationship between dietary fiber physicochemical properties and feedstuff fermentation characteristics and their effects on nutrient utilization, energy metabolism, and gut microbiota in growing pigs

BACKGROUND

There is a growing focus on using various plant-derived agricultural by-products to increase the benefits of pig farming, but these feedstuffs are fibrous in nature. This study investigated the relationship between dietary fiber physicochemical properties and feedstuff fermentation characteristics and their effects on nutrient utilization, energy metabolism, and gut microbiota in growing pigs.

METHODS

Thirty-six growing barrows (47.2 ± 1.5 kg) were randomly allotted to 6 dietary treatments with 2 apparent viscosity levels and 3 β-glucan-to-arabinoxylan ratios. In the experiment, nutrient utilization, energy metabolism, fecal microbial community, and production and absorption of short-chain fatty acid (SCFA) of pigs were investigated. In vitro digestion and fermentation models were used to compare the fermentation characteristics of feedstuffs and ileal digesta in the pig's hindgut.

RESULTS

The production dynamics of SCFA and dry matter corrected gas production of different feedstuffs during in vitro fermentation were different and closely related to the physical properties and chemical structure of the fiber. In animal experiments, increasing the dietary apparent viscosity and the β-glucan-to-arabinoxylan ratios both increased the apparent ileal digestibility (AID), apparent total tract digestibility (ATTD), and hindgut digestibility of fiber components while decreasing the AID and ATTD of dry matter and organic matter (P < 0.05). In addition, increasing dietary apparent viscosity and β-glucan-to-arabinoxylan ratios both increased gas exchange, heat production, and protein oxidation, and decreased energy deposition (P < 0.05). The dietary apparent viscosity and β-glucan-to-arabinoxylan ratios had linear interaction effects on the digestible energy, metabolizable energy, retained energy (RE), and net energy (NE) of the diets (P < 0.05). At the same time, the increase of dietary apparent viscosity and β-glucan-to-arabinoxylan ratios both increased SCFA production and absorption (P < 0.05). Increasing the dietary apparent viscosity and β-glucan-to-arabinoxylan ratios increased the diversity and abundance of bacteria (P < 0.05) and the relative abundance of beneficial bacteria. Furthermore, increasing the dietary β-glucan-to-arabinoxylan ratios led to a linear increase in SCFA production during the in vitro fermentation of ileal digesta (P < 0.001). Finally, the prediction equations for RE and NE were established.

CONCLUSION

Dietary fiber physicochemical properties alter dietary fermentation patterns and regulate nutrient utilization, energy metabolism, and pig gut microbiota composition and metabolites.

Microencapsulation of broccoli sulforaphane using whey and pea protein: in vitro dynamic gastrointestinal digestion and intestinal absorption by Caco-2-HT29-MTX-E12 cells

Sulforaphane, an organosulfur phytochemical, has been demonstrated to have significant anticancer potential in both in vitro and in vivo studies, exhibiting mechanisms of action that include inducing apoptosis, inhibiting cell proliferation, and modulating key signalling pathways involved in cancer development. However, its instability presents a major obstacle to its clinical application due to its limited bioavailability. This study aimed to improve the stability and thus the bioavailability of sulforaphane from broccoli by microencapsulation with whey (BW) and pea protein (BP) by freeze-drying. BW and BP were characterised by particle size measurement, colour, infrared spectroscopy, scanning electron microscopy, thermogravimetry, and differential scanning calorimetry. Dynamic in vitro gastrointestinal digestion was performed to measure sulforaphane bioaccessibility, in BP, BW and dried broccoli. A Caco-2-HT29-MTX-E12 intestinal absorption model was used to measure sulforaphane bioavailability. The in vitro dynamic gastrointestinal digestion revealed that sulforaphane bioaccessibility of BW was significantly higher (67.7 ± 1.2%) than BP (19.0 ± 2.2%) and dried broccoli (19.6 ± 10.4%) (p < 0.01). In addition, sulforaphane bioavailability of BW was also significantly greater (54.4 ± 4.0%) in comparison to BP (9.6 ± 1.2%) and dried broccoli (15.8 ± 2.2%) (p < 0.01). Microencapsulation of broccoli sulforaphane with whey protein significantly improved its in vitro bioaccessibility and bioavailability. This suggests that whey protein isolate could be a promising wall material to protect and stabilise sulforaphane for enhanced bioactivity and applications (such as nutraceutical formulations).

A fish intestinal in vitro model for investigation of lipid metabolism and steatosis

Choline is now recognized as an essential nutrient to ensure lipid transport in Atlantic salmon. Its deficiency leads to excessive lipid accumulation in the enterocytes, a condition known as steatosis. The knowledge of lipid metabolism and steatosis in fish remains limited, motivating the use of in vitro intestinal models to perform deeper explorations. This study aimed to create an in vitro steatosis model using RTdi-MI, a new cell line derived from the distal intestine of rainbow trout. Cells were exposed to varying oleic acid (OA) concentrations over different time points (24 h, 72 h, and 168 h). Results indicated that the increasing OA concentration enhanced intracellular lipid droplet formation. Quantitative lipid analysis confirmed OA accumulation, which intensified with prolonged exposure and increased OA dose. Moreover, all cells, including controls, exhibited fatty acid metabolic activity. Such outcome was confirmed by light and fluorescence microscopy. Additionally, RTdi-MI cells expressed genes involved in lipid metabolism and synthesis similar to in vivo conditions. Collectively, our findings demonstrate the ability of RTdi-MI cells to accumulate OA in intracellular lipid droplets and mirror in vivo steatosis conditions, offering a new tool for exploring fish intestinal lipid metabolism.

Antinutritional factors and protein digestibility of broad bean flours hydrolysed during soaking using vacuum enzyme impregnation

The hydrolysis of legume proteins improves their nutritional and functional properties. Usually done by mixing flour with an enzyme solution, the process can be simplified using vacuum enzyme impregnation during soaking. This study used vacuum impregnation with papain or bromelain to obtain hydrolysed broad bean flours. It examined the impact of vacuum impregnation and enzyme incorporation on hydration kinetics and the impact of hydrolysis and dehulling on antinutritional factors and protein digestibility. Vacuum impregnation accelerated hydration and enzyme incorporation did not alter the hydration rate. Maximum hydrolysis degrees were 9.1 % with papain and 8.8 % with bromelain after 4 h of soaking. Hydrolysis increased phytic acid, total phenolics, and tannins content while decreasing trypsin inhibitors. Dehulling increased phytic acid and trypsin inhibitors, reduced tannins, and enhanced protein digestibility. Vacuum enzyme impregnation during soaking was effective for hydration and protein hydrolysis, modifying the nutritional properties of broad bean flours.

The composition and bioactivity of bound polyphenols from coffee dietary fiber during in vitro Simulating digestion

Dietary fiber from coffee peel is rich in bound polyphenols good for human health due to the antioxidant activity. In this study, we evaluated the bound polyphenol release conditions and activities in coffee peel soluble dietary fiber (CPSDF) in the process of in vitro simulation digestion. The CPSDF structure became loose and porous due to simulated digestion but retained the polysaccharide backbone. Widely-targeted metabolomics analysis identified 550 metabolites, with phenolic acids and flavonoids being main differentially expressed metabolites in digested products (82.18% in total). The most significant increase in the 5,7,8,3',4'-pentamethoxyflavanone content and decrease in the 3,5-dihydroxyacetophenone content were observed after digestion (undigested vs S-intestine). Additionally, the changes in antioxidant and enzyme inhibitory activities followed the same pattern as that observed for total phenolic content. The enzyme inhibitory and antioxidant activities of gastric digestion products were greater than those of the oral and small intestinal digestion products. The present work provided the theoretical foundation for developing high-value CPSDF products and reusing coffee peel waste.

Physicochemical characterization and in vitro digestibility of resistant starch from corn starch sugar residue

This study sought to investigate the thermal stability and digestibility of corn starch sugar residue resistant starch (CSSR-RS) through comparative analysis of the physicochemical properties and structural characteristics among CSSR-RS, high-amylose corn starch (HS), and normal corn starch (NS). CSSR-RS contained 51.76 % resistant starch (RS), with 42.6 % remaining after high-temperature treatment, which was significantly higher than HS, demonstrating strong resistance to gelatinization. CSSR-RS is characterized by highly ordered aggregation of small molecules with a C-type crystalline structure, and irregular granular structures with wrinkled surfaces. Compared with NS and HS, the short-range and long-range order of CSSR-RS were significantly higher, indicating excellent thermal stability. In vitro simulated digestion revealed that the total hydrolysis rate of CSSR-RS was significantly lower than those of NS and HS, and the residual digesta of CSSR-RS also showed better resistance to digestion than HS. CSSR-RS exhibited significant development prospects in healthy food.

Helical structures modulate the complexation mode and release characteristics of starch-capsaicin complex

Capsaicin (CA) is a bioactive compound, known for its physiological effects, though its high pungency limits its practical applications. This study investigated the effects of starches with amorphous structures (AS), single helical and amorphous structures (SAS), and a combination of double helical, single helical, and amorphous structures (DSAS) on the complexation mode and release characteristics of CA. The SAS-CA complex exhibited the highest CA content (60.1 mg/g) and improved stability. Structural analyses using nuclear magnetic resonance spectroscopy and X-ray diffraction verified that both SAS and DSAS formed V6I-type complexes with CA stabilized by hydrogen bonding and hydrophobic interactions. In contrast, AS and CA exhibited only physical entrapment determined by differential scanning calorimetry, Fourier transform infrared, and Raman spectroscopy. The DSAS-CA complex demonstrated the slowest CA release during simulated oral digestion, attributed to its double helical structure, which resisted water erosion (17.1 %) and enzyme hydrolysis (3.6 %). Pearson correlation analysis revealed a strong positive relationship of CA release with amorphous structure, hydrolysis rate, and erosion rate, but exhibited a negative correlation with single helical and double helical structures. These findings support the development of starch-based delivery systems tailored to control the release of highly pungent bioactives like capsaicin, broadening their potential uses in food and pharmaceutical formulations.

New insights into ultrasound-assisted noncovalent nanocomplexes of β-lactoglobulin and neochlorogenic acid/cryptochlorogenic acid and its potential application for curcumin loading

The cross-linking sites and structure of protein-polyphenol complexes are susceptible to the type, structure, weight of polyphenols under nonthermal process. The low bioavailability and poor gastrointestinal instability of curcumin (CUR) hampers its application. Hence, changes in binding mechanism, structural and functional properties between β-lactoglobulin (β-LG) with two different configurations of chlorogenic acids (neochlorogenic acids (3-CQA) and cryptochlorogenic acids (4-CQA) by non-covalent binding under ultrasonic treatment, and the potential capacity for loading CUR were researched. The binding affinity scores of β-LG-4CQA was -7.1 kcal/mol. It is higher than β-LG-3CQA (-6.8 kcal/mol), which implied that the interaction between β-LG and 4-CQA was stronger. Circular dichroism calculations showed that the sonicated complex of the β-LG and 4-CQA with a decreased content of α-helices by 5.4 %, β-sheets by 4.6 %, and an increased content of irregular curls by 8.4 % (p < 0.05). The result demonstrated ultrasound and the binding of β-LG to 3/4-CQA improved the hydrophilicity, thermal stability, and antioxidant property of β-LG. Furthermore, the embedding rate of CUR in the ultrasound-assisted β-LG-4-CQA complex could reach 71.56 %. Consistent with the structural characterization results, the CUR release rate of ULG-4-CQA + CUR complex reached 17.36 % in simulated intestinal digestion, which was 8.09 % higher than free CUR. Indicating that after embedding with protein-polyphenol complexes, the stability and bioaccessibility of CUR was improved. This study reveals the potential application of ultrasound-assisted protein-polyphenol complexes for loading CUR.

Nanoencapsulation of vitamin B2 using chitosan-modified poly(lactic-co-glycolic acid) nanoparticles: Synthesis, characterization, and in vitro studies on simulated gastrointestinal stability and delivery

Vitamin B2, or riboflavin, is essential for maintaining healthy cellular metabolism and function. However, its light sensitivity, poor water solubility, and gastrointestinal barriers limit its storage, delivery, and absorption. Selecting suitable nanomaterials for encapsulating vitamin B2 is crucial to overcoming these challenges. This study employed chitosan-coated poly(lactic-co-glycolic acid) nanoparticles (CS-PLGA NPs) as a novel delivery system to enhance the bioavailability of vitamin B2 for food fortification and nutraceutical applications. The nanoparticles, with sizes below 200 nm, exhibited greater stability than PLGA NPs after freeze-drying and in simulated body fluids. Encapsulation improved the photostability of vitamin B2 under ultraviolet light and prolonged its release in simulated body fluids compared to non-encapsulated vitamin B2. Furthermore, CS-PLGA NPs demonstrated higher uptake in intestinal epithelial cells (Caco-2), indicating enhanced transport and potential for use in fortified food systems. These findings underscore the promise of CS-PLGA NPs for delivering vitamin B2 in food, nutraceutical, and pharmaceutical applications. PRACTICAL APPLICATION: The use of chitosan-coated PLGA NPs for encapsulating vitamin B2 offers a promising solution to enhance its bioavailability, especially for individuals with gastrointestinal absorption issues. This formulation improves stability, controlled release, and cellular uptake, which can lead to more effective supplementation strategies in nutraceutical and pharmaceutical applications. It could benefit patients with vitamin B2 deficiencies, such as those with malabsorption disorders, by ensuring efficient delivery through the gastrointestinal tract. Additionally, this approach can be applied to other water-soluble vitamins or bioactive compounds, offering a versatile platform for improving the efficacy of oral supplements.

Rat small intestine extract as a source of mammalian α- and β-glycosidases to study polyphenol bioaccessibility and deglycosylation in vitro: A case study with matrix-devoid and matrix-defined apple fractions

Most polyphenols are glycosylated, affecting their uptake, metabolism, and biological activity. However, the attached sugar must be removed before absorption and functionality can take place. Yet, despite the biological and chemical implications of polyphenol (de-)glycosylation, most in vitro digestion assays omit the utilization of intestinal brush border α- and/or β-glycosidases to study polyphenol bioaccessibility and deglycosylation. This study investigated the effect of rat small intestine extract (RSIE) as an affordable source of mammalian α- and β-glycosidases in different food matrices: matrix-devoid whole apple extract, whole apple, apple juice, and apple pomace. Using the INFOGEST 2.0 model, transepithelial polyphenol absorption, UHPLC-ESI-QTOF-MS/MS, and the inclusion of RSIE at the 15 U*mL-1 maltase activity reported in the human epithelium, the role of RSIE in polyphenol bioaccessibility and deglycosylation was explored. Moreover, the effect of the plant cell wall (PCW) matrix on the role of RSIE was mechanistically investigated by comparing whole apple (or pomace) with their respective extracts. 36 glycosylated polyphenols were identified, including 33 β-O-glycosides and 3 α-O-glycosides. The content of bioaccessible polyphenol β-O-glycosides and α-O-glycosides was significantly lower (p < 0.001) when RSIE was present, which resulted in a concomitant generation of the aglycone forms (phloretin, quercetin, ferulic acid, caffeic acid and p-coumaric acid). However, the concentration of aglycones was much lower than the reduction in the concentration of glycosylated polyphenols, strongly suggesting that polyphenols bind to RSIE. Matrix-devoid whole apple extract, or pomace extract, exhibited higher polyphenol bioaccessibility than whole apple or pomace, likely due to reduced interactions between polyphenols and the food matrix. Importantly, these differences in bioaccessibility diminished with RSIE, suggesting that RSIE α-glycosidases cleaved α-glucans and disrupted the PCW structure.

Digestive characteristics and structural changes of lotus seed starch-lotus seed protein blend system during in vitro digestion

This study analyzes the digestive characteristics, morphological changes, particle size distribution, and the evolution of crystalline and molecular structures of the lotus seed starch-lotus seed protein blend system (LS-LP) through simulated in vitro static and dynamic digestion experiments. The findings indicate that LS-LP, treated by high-pressure homogenization (HPH), exhibits a higher digestion rate and total digestibility compared to the physical mixture of lotus seed starch and protein (PM) and lotus seed starch (LS). Interestingly, scanning electron microscopy (SEM) observations reveal that during digestion, the structure of lotus seed protein (LP) changes, forming a physical barrier to LS, thereby partially slowing down the digestion process. Furthermore, the transformation in particle size distribution (PSD) from unimodal to bimodal, the progressive increase in crystallinity observed through X-ray diffraction (XRD) analysis, and the structural alterations in LP identified by Fourier Transform infrared spectroscopy (FTIR) provide additional confirmation of the structural changes of LS-LP during digestion. In summary, this study provides a new insight for the digestive characteristics and structural changes of LS-LP during in vitro digestion, and offers a scientific basis for further research on the impact of LS-LP digestion products on gut microbiota.

Application of thermally assisted high hydrostatic pressure to modify sorghum starch: multi-scale structure, techno-functional properties and digestibility

The effects of high hydrostatic pressure (HHP) (400-650 MPa) and holding temperature (25-50 °C) in thermally assisted HHP processing on multi-scale structure of starch (granule, crystalline and molecular), techno-functional properties, and digestibility of sorghum starch (SS) were evaluated. Response surface methodology has verified that the process impact on the modification of SS was dependent primarily on the pressure level. As HHP increased, processed SS progressively lost their granular structure and Maltese cross, indicating gradual structural disorder within the granules. These findings were associated with larger particles, resulting from increased swelling of the granules. The enthalpy changes of crystallite melting decreased from 22.7 (SS) to 0.1-26.9 J/g as a result of increases in pressure and temperature. Measurements of long- and short-range order of SS showed granules have not been completely gelatinized during processing. Water absorption index (1.7-5.4 g/g) and cold viscosity (52.7-94.3 cP) increased as pressure increased, against lowered gel strength (0.80-1.44 N), peak (1394-2735 cP), final (1499-3103 cP) and setback viscosities (233-1288 cP). Increased RS (27.3-35.8%) in processed SS was attributed to the amylose-lipid complex. The process did not affect RDS compared to native SS, but it decreased SDS. Combinations of HHP and temperature demonstrated the potential to produce different versions of physically modified SS suitable for a wide range of applications.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-06014-z.

Amplifying Bioactivity of blue honeysuckle (Lonicera caerulea L.) fruit puree through Ultrasonication: Antioxidant and antiproliferative activity

Blue honeysuckle (Lonicera caerulea L.) serves as a significant reservoir of polyphenol compounds. This impact of ultrasonication processing on the bioaccessibility of blue honeysuckle fruit puree during in vitro digestion was evaluated. The polyphenol compounds, antioxidant capacity and antiproliferative activity were measured, with a particular focus on determining the total proanthocyanidin content of the puree during digestion. The results revealed that the U300 W treatment significantly increased antioxidant content and enhanced the stability of antioxidant capacity, leading to stronger antiproliferative activity. A total of 33 compounds, including 14 phenolic acids, 5 flavanols, 1 flavanol-3-ol, 1 flavanone alcohol, 3 flavanones, 1 flavanone, and 8 non- polyphenols were found in both untreated and ultrasonicated puree during in vitro digestion. The untreated puree contained 22 compounds, while the ultrasonicated puree contained 33. Compared to untreated samples, ultrasonicated samples contained significantly higher levels of loganic acid, dihydrokaempferol, kaempferol derivatives, and plantagoside. Except for vanillic acid, citric acid, protocatechuic acid, and luteolin-4'-O-glucoside, the polyphenols showed a decreasing trend during oral-gastric-small intestinal-colon digestion. The U500 W ultrasonicated fruit puree exhibited the strongest antiproliferative activity. Overall, the results demonstrated that ultrasonication has the potential to enhance the bioaccessibility of antioxidant compounds and the antiproliferative activity of blue honeysuckle fruit puree.

The bioaccessibility of phenolic compounds, nutritional quality, and textural properties of gluten-free muffins enriched with artichoke leaves and green lentil protein isolate

Although the gluten-free market is expanding and offers a variety of products, there are still some deficiencies in the nutritional and sensory quality of these products. Therefore, this study explores the bioaccessibility of phenolic compounds, nutritional quality, and textural properties of gluten-free muffins enriched with artichoke leaves and green lentil protein (GLP) isolate, two novel ingredients introduced together for the first time in this context. The incorporation of GLP isolate aims to enhance the protein content, while artichoke leaves are evaluated for its potential to improve phenolic content and antioxidant activity. The muffins were also subjected to in vitro digestion to assess the bioaccessibility of phenolic compounds. The results demonstrated that the addition of GLP isolate increased the protein content 1.4 times, while artichoke leaves contributed to enhance the total phenolic content (TPC), flavonoid content (TFC), antioxidant activity (TAA), and ash content by 2.1, 5.4, 3.2-3.5, and 1.3 times, respectively. Nevertheless, the addition of artichoke leaves increased the hardness, gumminess, and chewiness of gluten-free muffins (p < 0.05). The bioaccessibility values of gluten-free muffins varied between 138% and 220%, 142% and 206%, and 40% and 160% for TAA, TPC, and TFC, respectively. Chlorogenic acid, ferulic acid, and quercetin derivatives were found as main phenolic compounds in gluten-free muffins enriched with artichoke leaves in undigested and all phase of digestion. This study provides valuable insights into the development of functional gluten-free muffins, highlighting the potential of artichoke leaves and GLP isolate as innovative ingredients in gluten-free food products. PRACTICAL APPLICATION: This study shows how adding green lentil protein and artichoke leaves to gluten-free muffins can make them healthier by boosting their protein, antioxidants, and other nutrients. However, while muffins became more nutritious, their texture changes. Food companies could use this information to improve gluten-free products, but they may need to adjust the recipe to improve the sensory properties.

Bench scale Layer-by-Layer microencapasulation of Lactiplantibacillus plantarum WCFS1

Layer-by-Layer (LbL) self-assembly encapsulation is a promising technology for the protection and delivery of lactic acid bacteria. However, laboratory-scale encapsulation is often time-consuming, involves intensive protocols tailored for small-scale operations, requires substantial amounts of energy and water, and results in a low yield of encapsulated biomass. Scaling-up this process to a bench-bioreactor scale is not simply a matter of increasing culture volume as different key parameters (not particularly relevant at lab scale) become critical, including biomass production, the number of polymer layers, and the biomass-to-polymer mass ratio. To our knowledge, this work is the first to address the optimization of each stage of the encapsulation process for Lactiplantibacillus plantarum WCFS1. These stages include biomass production, handling of encapsulation polymers [chitosan (Chi) and alginate (Alg)], critical LbL parameters (e.g., biomass concentration, washing steps). The encapsulation efficiency was assessed by plate-counting microorganisms before and after coating with the polymers layers, followed by spray- and freeze-drying dehydration using fructo-oligosaccharides (FOS) and maltodextrin as carriers. Once dehydrated, microorganisms were either exposed to gastrointestinal conditions or stored for 30 days at 25 and 30 °C. Supplementing culture media with glucose, controlling pH, and harvesting at the early stationary phase during biomass production increased the bacterial recovery after LbL encapsulation (decrease < 1 log unit) compared to bacteria grown under non-controlled conditions (decrease of 4 log units). Coating bacteria (B) with up to two polymer layers (B|Chi or B|Chi|Alg) did not significantly affect bacterial culturability, unlike adding further layers. Zeta-potential measurements enabled the determination of the optimal biomass-to-polymer mass ratio. Using up to a 10:1 bacterial-to-polymer ratio did not change the z-potential for B|Chi or B|Chi|Alg samples. After drying, a synergistic effect between the LbL coating and carrier compounds (FOS and maltodextrin) was observed in terms of culturability. LbL encapsulation mitigated thermal and acidic stresses during spray-drying and gastrointestinal exposure. These findings support scaling-up LbL encapsulation for delivering sensitive lactic acid bacteria strains to the gut.

Human milk fat globule delivers entrapped probiotics to the infant's gut and acts synergistically to ameliorate oxidative and pathogenic stress

The human milk fat globule membrane (hMFGM) and Lactobacillus modulate the infant's gut and benefit health. Hence, the current study assesses the probiotic potential of Lactiplantibacillus plantarum (MRK3), Limosilactobacillus ferementum (MK1) isolated from infant feces, and its interaction with hMFGM during conditions mimicking infant digestive tract. Both strains showed high tolerance to gastrointestinal conditions, cell surface hydrophobicity, and strong anti-pathogen activity against Staphylococcus aureus. During digestion, hMFGM significantly exhibited xanthine oxidase activity, membrane roughness, and surface topography. In the presence of hMFGM, survival of MRK3 was higher than MK1, and electron microscopic observation revealed successful entrapment of MRK3 in the membrane matrix throughout digestion. Interestingly, probiotic-membrane matrix interaction showed significant synergy to alleviate oxidative stress and damage induced by cell-free supernatant of Escherichia coli in Caco-2 cells. Our results show that a probiotic-encapsulated membrane matrix potentially opens the functional infant formula development pathway.

DAG-MAG-ΒHB: A Novel Ketone Diester Modulates NLRP3 Inflammasome Activation in Microglial Cells in Response to Beta-Amyloid and Low Glucose AD-like Conditions

BACKGROUND

A neuroinflammatory disease such as Alzheimer's disease, presents a significant challenge in neurotherapeutics, particularly due to the complex etiology and allostatic factors, referred to as CNS stressors, that accelerate the development and progression of the disease. These CNS stressors include cerebral hypo-glucose metabolism, hyperinsulinemia, mitochondrial dysfunction, oxidative stress, impairment of neuronal autophagy, hypoxic insults and neuroinflammation. This study aims to explore the efficacy and safety of DAG-MAG-ΒHB, a novel ketone diester, in mitigating these risk factors by sustaining therapeutic ketosis, independent of conventional metabolic pathways.

METHODS

We evaluated the intestinal absorption of DAG-MAG-ΒHB and the metabolic impact in human microglial cells. Utilizing the HMC3 human microglia cell line, we examined the compound's effect on cellular viability, Acetyl-CoA and ATP levels, and key metabolic enzymes under hypoglycemia. Additionally, we assessed the impact of DAG-AG-ΒHB on inflammasome activation, mitochondrial activity, ROS levels, inflammation and phagocytic rates.

RESULTS

DAG-MAG-ΒHB showed a high rate of intestinal absorption and no cytotoxic effect. In vitro, DAG-MAG-ΒHB enhanced cell viability, preserved morphological integrity, and maintained elevated Acetyl-CoA and ATP levels under hypoglycemic conditions. DAG-MAG-ΒHB increased the activity of BDH1 and SCOT, indicating ATP production via a ketolytic pathway. DAG-MAG-ΒHB showed remarkable resilience against low glucose condition by inhibiting NLRP3 inflammasome activation.

CONCLUSIONS

In summary, DAG-MAG-ΒHB emerges as a promising treatment for neuroinflammatory conditions. It enhances cellular health under varying metabolic states and exhibits neuroprotective properties against low glucose conditions. These attributes indicate its potential as an effective component in managing neuroinflammatory diseases, addressing their complex progression.

Metabolomics of black beans (Phaseolus vulgaris L.) during atmospheric pressure steaming and in vitro simulated digestion

In the paper, metabolomics techniques based on UHPLC-QE-MS were used to study raw black beans, steaming black beans, and their in vitro digestion products. The results show that the three groups of raw black beans, atmospheric pressure-steamed black beans, and their in vitro digests comprised 922, 945, and 878 characteristic metabolites, respectively, dominated by amino acids, organic acids, polyphenols, and sugars. After screening the differential metabolites, content comparison, the content of amino acids, sugars, and phenolics in black beans was found to be increased after atmospheric steaming. During in vitro digestion, the amino acid content increased and the phenolic content decreased, with amino acid synthesis, phenolic degradation, and conversion predominating. This study provides data to support the changes in black beans metabolites during atmospheric steam processing and in vitro digestion.

Comparative effects of non-fermented and Lacticaseibacillus paracasei-fermented pomelo juice on gut microbiota composition and short-chain fatty acid production: An in vitro colonic model

Pomelo juice, especially from the Tubtim Siam cultivar, may offer prebiotic benefits by promoting beneficial gut bacteria. This study evaluated the impact of non-fermented and Lacticaseibacillus paracasei (L. paracasei)-fermented pomelo juice on gut microbiota using an in vitro colonic fermentation model. The L. paracasei-fermented juice significantly increased lactobacilli levels compared to the non-fermented juice, while both treatments similarly suppressed coliforms within 24 h. Microbiota analysis revealed increased richness and significant community shifts in both treatments. Moreover, the fermented juice demonstrated a greater decrease in the Firmicutes/Bacteroidetes ratio, indicating a greater impact on gut metabolism. Fermented juice promoted beneficial bacteria like L. paracasei, Bifidobacterium longum, and Faecalibacterium prauznitzii while inhibiting pathogens. These changes coincided with higher production of short-chain fatty acids (SCFAs), including acetic, propionic, and n-butyric acids. Therefore, fermenting pomelo juice with L. paracasei improves its ability to beneficially influence the gut microbiota, suggesting its potential for gut health enhancement.

Multitarget Peptides Released by In Vitro Static Gastrointestinal Digestion of an Amaranth Protein Beverage

Beverages formulated from alternative proteins, such as amaranth, are gaining attraction due to changes in human dietary patterns and environmental concerns like resource use and biodiversity loss. This study focuses on assessing the bioactive peptide release from an amaranth protein beverage. This beverage was subjected to a static simulated gastrointestinal digestion (SGD) protocol to evaluate its bioaccessibility and functional potential. The digests were analyzed for in vitro antihypertensive, antioxidant, and antithrombotic activities. Additionally, digested peptide sequences were identified via LC-MS/MS. The results showed that SGD significantly enhanced the release of bioactive peptides, leading to increased ACE inhibition, antioxidant capacity against ABTS + and AAPH-induced radicals, and antithrombotic effects in clotting assays. LC-MS/MS analysis identified 31 peptides in the digests, ranging from 9 to 21 amino acids, associated with various bioactivities. These findings highlight amaranth proteins potential as a source of functional peptides with health-promoting properties. Further research must be done to isolate and characterize specific peptides for potential therapeutic applications.

Exploring the Functional Features of Melon Peel Flour for Healthier Bakery Products

The use of fruit by-products to develop new food products could be an advantageous approach to meet the demand for healthy foods and reduce food waste. In this study, the amino acid and mineral profiles of melon peel flour were evaluated. Non-essential/toxic elements were also determined. Furthermore, two formulations (biscuit and muffin) were developed with 50% and 100% melon peel flour, respectively. The bioaccessibility of essential minerals in these two formulations was also determined. These innovative products presented interesting contents of amino acids and high levels of minerals, contributing significantly to daily mineral requirements, mainly magnesium (18-23%), phosphorus (13-28%), molybdenum (14-17%), and manganese (10-13%). Regarding the in vitro bioaccessibility of minerals in the developed formulations, magnesium, manganese, sodium, and phosphorus were those with the highest values (75-108%). Based on these results, melon peel has the potential to improve global food security, nutrition, economic well-being, and overall health and well-being.

Formulation of Hydrogel Beads to Improve the Bioaccessibility of Bioactive Compounds from Goldenberry and Purple Passion Fruit and Evaluation of Their Antiproliferative Effects on Human Colorectal Carcinoma Cells

Goldenberry and purple passion fruit contain bioactive compounds (BCs) that can prevent gastrointestinal cancers; hydrogel beads can protect and control their release in the gastrointestinal tract. This study aimed to develop an encapsulating material for fruit hydrogel beads (FHBs) to increase their bioaccessibility and to assess antiproliferative effects. A blend of goldenberry-purple passion fruit was encapsulated using ionic gelation and electrospraying. Through a mixture experimental design with sodium alginate (SA), hydroxypropylmethylcellulose (HPMC) and arabic gum (AG) as components, the following response variables were optimized: polyphenol bioaccessibility and encapsulation efficiency. Polyphenols and antioxidant activity were quantified before and after digestion. Antiproliferative effect was evaluated on Caco-2 colon cancer cells. Variations in formulation proportions had a significant effect (p < 0.05) on most responses. An SA-AG mixture in a 0.75:0.25 ratio maximized polyphenol bioaccessibility to 213.17 ± 19.57% and encapsulation efficiency to 89.46 ± 6.64%. Polyphenols and antioxidant activity were lower in FHBs than in the fruit blend (F). Both F and FHBs inhibited tumor cell proliferation by 17% and 25%, respectively. In conclusion, encapsulating BCs in hydrogel beads with SA-AG can enhance the effectiveness of polyphenols in food applications by improving their bioaccessibility and showing a more pronounced effect in inhibiting tumor cell proliferation.

Enhancing Digestibility and Intestinal Peptide Release of Pleurotus eryngii Protein: An Enzymatic Approach

Pleurotus eryngii is a tasty and low-calorie mushroom containing abundant high-quality protein. This study aims to improve the digestibility of P. eryngii protein (PEP) and hence to facilitate its development as a healthy alternative protein. The extracted PEP was pretreated with 1000-5000 U of papain, neutral protease and alkaline protease. The Chyme collected from in vitro simulated gastrointestinal digestion was analyzed by fluorescence microscopy and protein particle analyzer, and the endpoint profiles of peptides and amino acids were determined by UHPLC-MS/MS and NanoLC-MS/MS. The particle size curve and fluorescence microscopy images jointly supported that protease hydrolysis improved decomposition and dispersion of PEP during digestion, particularly in the gastric phase. The impact on Zeta potential was minimal. Proteases effectively increased the abundance of amino acids after digestion, particularly L-isomer Lys and Arg Maximum release was achieved when pretreated with 5000 U of alkaline protease, reaching 7.54 times that of control. Pretreatments by proteases also notably increased digestive yields of 16,736-19,870 peptides, with the maximum reaching 1.70 times that of the control, which mainly consisted of small peptides composed of 7-15 amino acids with molecular weight below 800 Da. The findings indicated that protease hydrolysis, especially pretreatment with 5000 U of alkaline protease, effectively enhanced the digestibility of PEP, which shed light on providing enzymatic approaches for improving bioavailability and developing healthy fungal proteins.

Neo-Glycolipid Oximes as Intestinal Permeation Enhancers for Peptide Hormone PYY3-36

Herein, we describe the design and synthesis of 16 neo-glycolipids that are potential permeation enhancers for oral drug delivery of peptide therapeutics. These amphiphilic neo-glycolipids are composed of fatty acids and various carbohydrates (d-glucose, lactose, cellobiose, maltose) via an oxime linker. The ability of the synthesized neo-glycolipids to enhance permeation of fluorescein-labelled dextran (4 kDa) or 3H-mannitol across intestinal epithelium was investigated in vitro using monolayers of human epithelial Caco-2 cells. Their effects were compared with (pre-)clinically known enhancers as reference compounds; sodium salts of octanoic, decanoic, and dodecanoic acid, and sodium salcaprozate (SNAC). Most neo-glycolipids increased the permeation of the model compounds, proving that neo-glycolipids, which possess vastly different properties from the reference compounds, e. g., in terms of clogD and polar surface area, are effective permeation enhancers. The neo-glycolipid based on decanoic acid and glucose was more potent than related compounds based on disaccharides. Significant differences in solubility and cellular compatibility were found for neo-glyolipids based on different carbohydrates. Finally, neo-glycolipids were evaluated as permeation enhancers for the peptide hormone PYY3-36. Glucose- and maltose-derived neo-glycolipids based on decanoic and dodecanoic acid showed promising enhancements in PYY3-36 permeation in vitro while maintaining good cellular compatibility, relevant for oral delivery of obesity treatments.