Simulated Intestinal Conditions Research Articles

Screening of a potential probiotic Lactiplantibacillus plantarum NUC08 and its synergistic effects with yogurt starter

This study aims to identify lactic acid bacteria (LAB) isolates possessing physiological characteristics suitable for use as probiotics in yogurt fermentation. Following acid and bile salt tolerance tests, Lactiplantibacillus plantarum (NUC08 and NUC101), Lacticaseibacillus rhamnosus (NUC55 and NUC201), and Lacticaseibacillus paracasei (NUC159, NUC216 and NUC351) were shortlisted based on intraspecies distribution for further evaluation. Their physiological probiotic properties, including transit tolerance, adhesion, auto-aggregation, surface hydrophobicity, biofilm formation, and antibacterial activity, were assessed. Principal Component Analysis (PCA) indicated that L. plantarum NUC08 was the preferred choice among the evaluated strains. Subsequent investigations revealed that co-culturing L. plantarum NUC08 with 2 yogurt starter strains resulted in a cooperative and synergistic effect, enhancing the growth of mixed strains and increasing their tolerance to simulated gastric and intestinal conditions. Additionally, when Vibrio harveyi bioluminescent reporter strain was used, the 3 cocultured strains cooperated to induce the activity of a quorum sensing (QS) molecule AI-2, hinting a potential connection between phenotypic traits and QS in the cocultured strains. Importantly, LAB viable counts were significantly higher in yogurt co-fermented with L. plantarum NUC08, consistently throughout the storage period. In conclusion, the study demonstrates that the probiotic strain L. plantarum NUC08 can be employed in synergy with yogurt starter strains, affirming its potential for use in the development of functional fermented dairy products.

Studies on different polysaccharides used as carrier material for spray-drying of synbiotics and its viability under different storage conditions

The objective of this study was to investigate the different polysaccharides as carrier material for spray-drying synbiotics and to study the physicochemical characteristics of synbiotics at different storage conditions. The thermally acclimatized probiotic strains, Lactobacillus helveticus (H-45) and Lacticaseibacillus casei (N-45) with enhanced probiotic properties were spray-dried using these polysaccharides along with galactooligosaccharides (GOS) as prebiotic. The studied plant-based polysaccharides are maltodextrin (MDX), corn starch (CS), and gum acacia (GA). After spray-drying, the survivability of all synbiotic combinations was higher in the presence of corn starch as carrier material. The synbiotic combination N45 + GOS + CS showed better survivability during spray-drying, under simulated intestinal (8.43 ± 0.17 log CFU/g), acid (5.51 ± 0.12 log CFU/g), and bile (7.31 ± 0.04 log CFU/g) conditions. The spray-dried powders had good to moderate flow properties with moisture content and water activity (aw) at the optimal range for the survival of probiotics. Among the spray-dried powders, synbiotic-N45 + GOS + CS showed improved storage survivability during shelf-life studies at three different temperatures (4 °C, 30 °C, and 37 °C) for eight weeks. However, all spray-dried probiotic and synbiotic powders had higher viability when stored at 4 °C. Hence, the study suggests that cornstarch as a polysaccharide in the synbiotics formulation (N45 + GOS + CS) may have a potential application in functional foods.

Lymphatic Uptake of a Highly Lipophilic Protease Inhibitor Prodrug from a Lipid-Based Formulation is Limited by Instability in the Intestine

Dabigatran etexilate (DABE) is a lipophilic double alkyl ester prodrug of dabigatran (DAB) which is a serine protease inhibitor used clinically as an anticoagulant. Recently, translocation of serine protease enzymes, including trypsin, from the gut into the mesenteric lymph and then blood has been associated with organ failure in acute and critical illnesses (ACIs). Delivery of DABE into mesenteric lymph may thus be an effective strategy to prevent organ failure in ACIs. Most drugs access the mesenteric lymph in low quantities following oral administration, as they are rapidly transported away from the intestine via the blood. Here, we examine the potential to deliver DABE into the mesenteric lymph by promoting association with lymph lipid transport pathways via co-administration with a lipid-based formulation (LBF). A series of self-emulsifying LBFs were designed and tested in vitro for their potential to form stable DABE loaded emulsions and keep DABE solubilised and stable over time in simulated gastrointestinal conditions. The LBFs were found to form fine emulsions with a droplet size of 214 ± 30 nm and DABE was stable in the formulation. The stability of DABE in vitro in simulated intestinal conditions, plasma and lymph samples was also evaluated to ensure stability in collected samples and to evaluate whether the prodrug is likely to release active DAB. Ultimately, a highly uniform and stable self-emulsifying Type III A LBF of DABE was chosen for progression into in vivo studies in male Sprague Dawley rats to confirm the lymphatic uptake and plasma pharmacokinetics. Both in vitro and in vivo in plasma and lymph, DABE was rapidly converted to an intermediate and DAB. The main species present in vivo in both plasma and lymph was DAB and mass transport of DABE and DAB in lymph was minimal (∼0.5 % of dose). Importantly, the concentration of DABE in lymph was substantially (20–176 fold) higher than in plasma, supporting that if the prodrug were stable and did not convert to DAB in the intestine, it would be lymphatically transported. Future studies will therefore focus on optimizing the design of the prodrug and formulation to improve stability during absorption and further promote lymphatic uptake.

The Impact of Polymers on Enzalutamide Solid Self-Nanoemulsifying Drug Delivery System and Improved Bioavailability.

Enzalutamide (ENZ), marketed under the brand name Xtandi® as a soft capsule, is an androgen receptor signaling inhibitor drug actively used in clinical settings for treating prostate cancer. However, ENZ's low solubility and bioavailability significantly hinder the achievement of optimal therapeutic outcomes. In previous studies, a liquid self-nanoemulsifying drug delivery system (L-SNEDDS) containing ENZ was developed among various solubilization technologies. However, powder formulations that included colloidal silica rapidly formed crystal nuclei in aqueous solutions, leading to a significant decrease in dissolution. Consequently, this study evaluated the efficacy of adding a polymer as a recrystallization inhibitor to a solid SNEDDS (S-SNEDDS) to maintain the drug in a stable, amorphous state in aqueous environments. Polymers were selected based on solubility tests, and the S-SNEDDS formulation was successfully produced via spray drying. The optimized S-SNEDDS formulation demonstrated through X-ray diffraction and differential scanning calorimetry data that it significantly reduced drug crystallinity and enhanced its dissolution rate in simulated gastric and intestinal fluid conditions. In an in vivo study, the bioavailability of orally administered formulations was increased compared to the free drug. Our results highlight the effectiveness of solid-SNEDDS formulations in enhancing the bioavailability of ENZ and outline the potential translational directions for oral drug development.

Limosilactobacillus reuteri HCS02-001 Attenuates Hyperuricemia through Gut Microbiota-Dependent Regulation of Uric Acid Biosynthesis and Excretion.

Hyperuricemia is a prevalent metabolic disorder that arises from abnormal purine metabolism and reduced excretion of uric acid (UA). The gut microbiota plays a significant role in the biosynthesis and excretion of UA. Probiotics capable of purine degradation possess the potential to prevent hyperuricemia. Our study aimed to screen probiotics in areas with abundant dairy products and longevity populations in China, which could attenuate the level of UA and explore the underlying mechanism. In this study, twenty-three lactic acid bacteria isolated from healthy Chinese infant feces and traditional fermented foods such as hurood and lump milk were evaluated for the ability to tolerance acid, bile, artificial gastric juice, and artificial intestinal juice to determine the potential of the candidate strains as probiotics. Eight strains were identified as possessing superior tolerance to simulated intestinal conditions and were further analyzed by high-performance liquid chromatography (HPLC), revealing that Limosilactobacillus reuteri HCS02-001 (Lact-1) and Lacticaseibacillus paracasei HCS17-040 (Lact-2) possess the most potent ability to degrade purine nucleosides. The effect of Lact-1 and Lact-2 on hyperuricemia was evaluated by intervening with them in the potassium oxonate and adenine-induced hyperuricemia Balb/c mice model in vivo. Our results showed that the level of serum UA in hyperuricemic mice can be efficiently reduced via the oral administration of Lact-1 (p < 0.05). It significantly inhibited the levels of liver inflammatory cytokines and hepatic xanthine oxidase through a TLR4/MyD88/NF-κB pathway across the gut-liver axis. Furthermore, UA transporters ABCG2 and SLC2A9 were substantially upregulated by the intervention of this probiotic. Fecal ATP levels were significantly induced, while fecal xanthine dehydrogenase and allantoinase levels were increased following probiotics. RNA sequencing of HT-29 cells line treated with Lact-1 and its metabolites demonstrated significant regulation of pathways related to hyperuricemia. In summary, these findings demonstrate that Limosilactobacillus reuteri HCS02-001 possesses a capacity to ameliorate hyperuricemia by inhibiting UA biosynthesis via enhancing gastrointestinal barrier functions and promoting UA removal through the upregulation of urate transporters, thereby providing a basis for the probiotic formulation by targeting the gut microbiota.

The SlpX protein plays a crucial role in the intestinal juice tolerance of Lactobacillus acidophilus CICC6074

The survival ability of lactic acid bacteria (LAB) in the gastrointestinal tract is low, and the mechanism of LAB resistance to the gastrointestinal tract's harsh environment is unclear. Therefore, this study used simulated gastrointestinal juices in vitro and transcriptomics approaches to identify proteins in Lactobacillus acidophilus CICC6074 that can enhance the strain's tolerance to gastrointestinal juices and verify the function of the target proteins. The results showed that the survival rate of Lactobacillus acidophilus CICC6074 was 79.24% after 6 h of in vitro intestinal juice treatment, and there were 10 genes coding proteins with significant changes in expression, among which S-layer protein gene slpX was significantly up-regulated. After overexpression of the slpX gene, the survival rate of Lactobacillus acidophilus CICC6074 was 94.35% after 6 h of in vitro intestinal juice tolerance. In conclusion, the SlpX protein plays a crucial role under the simulated intestinal juice condition of Lactobacillus acidophilus CICC6074. This study provides a basis for a deeper understanding of the survival mechanisms of Lactobacillus acidophilus in the gastrointestinal tract.

Assessment of Potential Probiotic Properties and Biotechnological Activities of Lactobacillus Strains Isolated from Traditional Algerian Fermented Wheat ELHAMOUM

Background: The objective of the current study was to explore the in vitro probiotic and technological characteristics of lactic acid bacteria (LAB) isolated from Algerian fermented wheat. Methods: Three LAB strains were selected and identified using 16S rRNA gene sequencing, in vitro assessments of probiotic properties included resistance to simulated gastric and intestinal conditions, auto-aggregation and antimicrobial susceptibility against common pathogens. Furthermore, the strains were evaluated for their biotechnological properties. Results: The results of 16S rRNA gene sequencing showed that two of them were Levilactobacillus brevis (LAn91 and LAn110) and LAn12a was Lactiplantibacillus pentosus. The tolerance of all strains to gastric acid and bile salts was more than 90%; they showed a high auto-aggregation capacity and a variable antagonistic property against pathogenic strains. Strain LAn12a presented the best biotechnological characteristics (proteolytic, acidifying and lactose hydrolysis), while the LAn91 and LAn110 strains were not able to acidify milk. All the strains exhibited a survival count in fermented milk exceeding 7 log CFU/ml during storage at 4°C on day 21, which surpasses the requirement of 6 log CFU/ml to provide health benefits. These bacteria can also be employed for the creation of functional foods and to validate their suitability as probiotic starter cultures.

Preparation and characterization of iota carrageenan-cyclodextrin-curcumin fibers and the release nature of curcumin in simulated digestion conditions

Healthy foods, known as functional and medicinal foods, are gaining popularity as they contain reasonable amounts of bioactive compounds (BCs) that can boost immunity. However, the intrinsic water insolubility and instability of BCs limit the design and development of healthy foods. To this end, carriers are effective in overcoming these setbacks. Among the several carrier choices, herein, human-compatible hydrocolloid iota-carrageenan (IC), a food hydrocolloid with the ability to form thermos-reversible gels, is chosen due to its intrinsic non-toxic and inexpensive traits. The ordered network structures of iota-carrageenan have been created by complexing with α-, β-, and γ-cyclodextrin (CD); later, curcumin has been encapsulated. Curcumin release has been tested in aqueous, simulated gastrointestinal, and simulated intestinal conditions. The maximum curcumin release was obtained in the aqueous conditions, and the IC fibers containing 50 mM NaCl displayed the highest curcumin release of 1.55 mg/g, followed by IC50-0.1β-CD of 1.37 mg/g. On the other hand, in IC fibers with 100 mM NaCl, the best release obtained was from IC100-0.1γ-CD and IC100 of 0.84 and 0.83 mg/g, respectively, and the minimum release of 0.39 mg/g was from the IC100-0.5γ-CD fibers. In simulated gastric fluid (SGF) media (pH 1.2), the highest release detected was 0.26 mg/g from the fibers with 50 mM NaCl. However, in simulated intestinal fluid (SIF) conditions (pH 6.8), the maximum achieved release of 1.00 mg/g was from the IC50 fibers, followed by 0.93 mg/g from the IC50-0.1β-CD fibers. Overall, the IC-CD network thermally protects curcumin, and the type of CD impacts its sustained release nature. The outcome is important in designing value-added delivery systems of bioactive compounds required to develop novel functional foods and improve human health.

High internal phase emulsions stabilized by pea protein isolate-EGCG-Fe3+ complexes: Encapsulation of β-carotene

Protein complexes have great potential for forming and stabilizing high internal phase emulsions (HIPEs) loaded with bioactive compounds. In this study, we investigated the potential of three types of complexes, namely pea protein isolate (PPI), PPI-epigallocatechin gallate (EGCG) and PPI-EGCG-Fe3+, to form and stabilize HIPEs with a 75% oil phase volume fraction. Initially, the impact of pH and emulsifier type on emulsions performance was investigated. Confocal laser scanning microscopy (CLSM) and particle size analysis showed that all three complexes could form HIPEs that remained stable under acidic and neutral conditions. These emulsions contained uniform oil droplets coated by a layer of the complexes. Notably, the PPI-EGCG-Fe3+ complexes formed HIPEs with the highest thermal and storage stability, which was attributed to the denser and thicker interfacial coatings. These emulsions also protected encapsulated β-carotene from degradation when exposed to light and thermal stress conditions. Furthermore, we measured lipid digestion and β-carotene bioaccessibility in the emulsions using an in vitro digestion model. The PPI-EGCG-Fe3+ stabilized emulsions not only exhibited slow fatty acid release but also enhanced β-carotene bioaccessibility (46.5%) under simulated small intestine conditions. This study demonstrates the potential of using protein-polyphenol-Fe3+ complexes to form and stabilize HIPEs, which may then be used to enhance the bioaccessibility and bioactivity of hydrophobic nutraceuticals.

In vitro digestion under simulated saliva, gastric and small intestinal conditions and fermentation of nicotinamide mononucleotide, and its effects on the gut microbiota

Nicotinamide Mononucleotide (NMN) is a derivative of vitamin B3, which plays a significant role in a plethora of metabolic reactions in the human body and is intricately associated with both immunity and metabolism. Nonetheless, in the intestine metabolic pathway of NMN and the relationship between NMN, gut microbiota, and SCFAs remain hitherto obscure. This study examined the digestion of NMN in simulated saliva, gastric, and small intestine environments, as well as exploring the interaction between NMN and human gut microbiota utilizing an in vitro fermentation model. NMN was progressively degraded into nicotinamide ribose (NR), nicotinamide (NAM), and ribose, with niacinate (NA) constituting the ultimate degradation product due to hydrolysis and metabolism by microbiota. NMN was ingested by human intestinal microbiota with a slower fermentation rate. As a result of NMN ingestion by human gut bacteria，the concentrations of propionate and butyrate increased by 88% and 23%, respectively, compared to the blank control group, the proliferation of beneficial gut bacteria (Bifidobacterium, Phascolarctobacterium, Faecalibacteriun, and Alistipes) significantly increased, while the proliferation of some harmful bacteria (Sutterella, Desulfovibrio and Pseudomonas) drastically declined. These findings illustrated the metabolic processes of NMN in the intestine, elaborating the relationship between NMN, SCFAs and gut microbiota. NMN might be a potential prebiotic to improve intestinal health.

Development of curcumin-loaded nanoemulsion stabilized with texturized whey protein concentrate: Characterization, stability and invitro digestibility.

The impacts of pH (2.8, 4.5, and 7.2) and extrusion cooking temperature (60°C, 85°C, and 110°C) on properties of native whey protein concentrate (NWPC) were evaluated, followed by delivering of curcumin through a nanoemulsion system stabilized with extruded WPC (EWPC). Protein solubility, surface hydrophobicity, and emulsion properties such as emulsion activity index (at 1% [w/w] protein concentration), stability index (at 0.5%, 1%, 2%, and 4% [w/w] protein concentration) and creaming index (evaluated at different protein concentrations [0.5%, 1%, 2%, and 4% w/w] and oil levels [20%, 40%, 60%, and 80%]) were improved as a function of the extrusion process. It was found that both covalent and non-covalent interactions contributed to the stabilization of the extrudates. The rheological investigation of the emulsions stabilized with EWPC (at different oil levels [20%, 40%, 60%, and 80%]) revealed high viscosity and shear thinning behavior as well as much higher G' and G″ values. Encapsulation efficiency was increased from 90.8% to 95.7% when NWPC and EWPC were used, respectively. The curcumin-loaded nanoemulsion containing EWPC presented high stability in confronting with ionic strength (NaCl salt with a concentration of 0.1-1 M), pH (3, 5, and 7), thermal treatments (pasteurization at 63°C for 30 min and sterilization at 95°C for 10 min) and storage time (1 month at 4°C and 25°C). Invitro release behavior revealed that samples stabilized with EWPC showed burst release in simulated intestine conditions. However, it was more stable in stomach conditions.

Exfoliated clay-polymer nanocomposite as a promising delivery system for bovine serum albumin

ABSTRACT The pH-sensitive exfoliated clay-alginate composite was investigated for the controlled oral delivery of bovine serum albumin (BSA). The X-ray diffraction analysis and transmission electron microscopy analysis revealed the exfoliated structure of clay in the composite. The degree of exfoliation was increased with sonication and it was optimised that the maximum exfoliation of clay in the aqueous medium occurred for 150 min of sonication. The maximum adsorption of BSA in the clay-alginate was detected at a pH of 4.5. The in-vitro release study of BSA from the exfoliated clay and the clay-alginate composite was analysed at simulated gastric and simulated intestinal pH conditions which suggested that the adsorption and release of BSA could be controlled simply by adjusting the solution pH condition. In the in-vitro release study, it was noted that there was no release of BSA from the clay-alginate composite up to 30 min in gastric pH conditions. But, there was a slow release rate of BSA within 10 h from the clay-alginate composite in the intestinal pH condition. The release profile from the clay–alginate composite was more fitted to the Peppas kinetic model.

Impact of microencapsulated bael pulp waste pectin as potential prebiotic on the viability of Bacillus clausii and Saccharomyces boulardii under simulated intestinal conditions

Impact of microencapsulated bael pulp waste pectin as potential prebiotic on the viability of Bacillus clausii and Saccharomyces boulardii under simulated intestinal conditions

Influence of polysaccharide-based co-encapsulants on efficiency, stability, and release of vitamins B12 and D3 in multilayered microcapsules

This study developed co-loaded vitamin B12 (vitB12) and D3 (vitD3) solid microcapsules using W1/O/W2 emulsions, followed by spray-drying. The effects of four polysaccharide-based gels as co-encapsulants on the microcapsules' morphological characteristics, encapsulation efficiency, storage stability, and gastrointestinal simulation were explored. The electrostatic bonding with chitosan in W1 and multilayer protection from the W1/O/W2 structure cause the high encapsulation efficiency of vitB12 (88.3 ± 0.8%–92.7 ± 1.1%). Further, adding polysaccharides into W2 improved the particle integrity of the dried powders and enhanced the retention rate and encapsulation efficiency of vitamins. Stability testing revealed that the encapsulation matrix incorporating sodium carboxymethylcellulose provided the best protection for vitB12 (plateau values of 97.8 and 95.8% at 25 and 40 °C, respectively) and lower degradation rates for vitD3 (decay constants kD of 0.26 and 0.49%/day). The formulation containing sodium alginate exhibited a controlled release of core components under simulated gastric conditions and the highest cumulative release (91.1 ± 5.3% vitB12 and 81.9 ± 3.6% vitD3) under simulated intestinal conditions. Our study suggests that the co-encapsulation strategy using the W1/O/W2 structure and spray-drying can be utilised to obtain good commercial products containing hydrophilic and lipophilic components, and polysaccharides as co-encapsulants can effectively regulate the chemical stability and release behaviour of the encapsulated components.

Nanoencapsulation of crocin in double-layer emulsions for improved stability and enhanced efficacy against depression.

On average, depression affects 7.7% of the population aged 15 and older. One of the types of medicinal plants used to treat depression is saffron, which is uplifting and relieves sadness. Crocin as a bioactive compound is effective against depression, but it is sensitive to temperature, pH, and oxygen, and its efficiency decreases. Nanoencapsulation of crocin using double-layer emulsions is a method to increase the stability of this compound. Surfactant ratio (50% to 200%), stirrer speed (500 and 1000 rpm), and stirring time (45, 90, and 135 min) were used as variables of primary emulsion production. The optimum ratio of surfactant to aqueous phase was 100%, and in all microemulsions, viscosity increased with increasing surfactant ratio. A high-pressure homogenization method was used to make the secondary emulsion (double-layer emulsions), and soy protein concentrate (SPC), Gum Arabic (GA), and Pectin (P) at two levels of 5 and 10% were used to increase the stability. All treatments evaluated using Duncan's test at a significance level of 5%. Double-layer emulsions stabilized with pectin showed the highest viscosity and the lowest release of crocin in simulated stomach and intestine conditions. The use of the cellular automata model to investigate the release of crocin showed that this model could simulate the effects of crocin concentration, polymer concentration, and the droplet size of double-layer emulsions with 93-99% confidence to predict the release in double-layer emulsions. Then the double-layer emulsions added to the chocolate, and the chocolate containing the double-layer emulsions compared with the control sample in terms of sensory properties and had a higher score than the control sample.

Effect of prebiotics on thermally acclimatized lactobacilli cultures and their application as synbiotics in RTD fruit drinks.

In this study, the effect of prebiotics such as fructooligosaccharides (FOS), galactooligosaccharides (GOS), isomaltooligosaccharides (IMO), and inulin on the probiotic biomass and its probiotic properties were studied for thermally acclimatized Lactobacillus helveticus (H-45) and Lacticaseibacillus casei N (N-45) strains at 45℃ using adaptive laboratory evolution method. Among the prebiotics studied, GOS was found to be more suitable for synbiotic preparation. The tolerance of lactobacilli cultures H-45 and N-45 in the presence of acid and bile were 4.79 and 8.60% and 2.84 and 4.65% higher than their wild-type strains (H-37 and N-37). Similarly, H-45 and N-45 showed an increase in survivability of 5.29 and 8.63% under simulated gastric conditions and 9.21 and 7.70% under simulated intestinal conditions than H-37 and N-37. Propionic acid yield increased by 0.65-fold in N-45 compared to N-37 in the presence of GOS as a prebiotic, whereas H-37 showed 0.26-fold higher propionic acid production than H-45. Thermally acclimatized strain N-45 showed better survivability under stress conditions than H-45. The synbiotic combination of N45 + GOS was spray-dried using corn starch (CS) as carrier material to obtain spray-dried synbiotic powder (N45 + CS + GOS). This synbiotic powder was added to the ready-to-drink (RTD) fruit drinks prepared from five fruit-flavoured squashes (pineapple, orange, grape, mango, and lemon ginger). The varied amounts of added synbiotic powder did not significantly alter the physicochemical properties of the fruit drinks. Hence, synbiotic formulation N45 + GOS + CS may find application in developing various functional foods.

Oral enzyme therapy for maple syrup urine disease (MSUD) suppresses plasma leucine levels in intermediate MSUD mice and healthy nonhuman primates.

Maple syrup urine disease (MSUD) is an inborn error of branched-chain amino acid metabolism affecting several thousand individuals worldwide. MSUD patients have elevated levels of plasma leucine and its metabolic product α-ketoisocaproate (KIC), which can lead to severe neurotoxicity, coma, and death. Patients must maintain a strict diet of protein restriction and medical formula, and periods of noncompliance or illness can lead to acute metabolic decompensation or cumulative neurological impairment. Given the lack of therapeutic options for MSUD patients, we sought to develop an oral enzyme therapy that can degrade leucine within the gastrointestinal tract prior to its systemic absorption and thus enable patients to maintain acceptable plasma leucine levels while broadening their access to natural protein. We identified a highly active leucine decarboxylase enzyme from Planctomycetaceae bacterium and used directed evolution to engineer the enzyme for stability to gastric and intestinal conditions. Following high-throughput screening of over 12 000 enzyme variants over 9 iterative rounds of evolution, we identified a lead variant, LDCv10, which retains activity following simulated gastric or intestinal conditions in vitro. In intermediate MSUD mice or healthy nonhuman primates given a whey protein meal, oral treatment with LDCv10 suppressed the spike in plasma leucine and KIC and reduced the leucine area under the curve in a dose-dependent manner. Reduction in plasma leucine correlated with decreased brain leucine levels following oral LDCv10 treatment. Collectively, these data support further development of LDCv10 as a potential new therapy for MSUD patients.

In vitro dynamic digestion properties of cooked rice and effect of the digesta on gut microbiota in a colonic fermentation model

The aim of this study was to evaluate the in vitro dynamic digestion behavior of three main rices [Indica rice (IR), Japonica rice (JR) and Waxy rice (WR)] and the influence of their digesta on the microorganism growth. Herein was shown that the cooked JR with the highest ratio of amylose (6.8 ± 0.2%) and lowest protein content (3.4 ± 0.1%) had the highest gastric retention rate (19.3 ± 5.2%) and exhibited slowest hydrolysis rate of starch (73.5 ± 2.5%) under simulated small intestinal conditions. The microstructure of WR disintegrated the fastest during the gastric stage, which may be attributed to its most soften texture (hardness: 2859.9 ± 214.5 g), lowest content of amylose (0.8 ± 0.1%) and highest ratio of protein (3.8 ± 0.1%). Besides, 16 sRNA detection possessed the digesta of these cooked rices can regulate the growth of beneficial bacteria in the Changdao Moni simulation system (CDMN) and reduce the abundance of proliferation of Shigella and Escherichia coli. JR digesta had the strongest ability to promote the synthesis of butyric acid (1.6 mg/mL) and valeric acid (1.8 mg/mL). The results may offer some suggestions on designing low glycemic food for special populations, and hope to inspire the development of novel starchy products to regulate the gut microbiota.

An In Vitro Comparison of the Digestibility and Gastrointestinal Fate of Scallops and Plant-Based Scallop Analogs.

Concerns exist regarding the negative environmental impact and health risks associated with ocean fishing and aquaculture, such as stock depletion, pollution, biodiversity loss, and toxin presence. To address these concerns, plant-based seafood analogs are being developed. Our previous study successfully created plant-based scallop analogs using pea proteins and citrus pectin, resembling real scallops in appearance and texture. This study focuses on comparing the digestive fate of these analogs to real scallops, as it can impact their nutritional properties. Using an in vitro digestion model (INFOGEST), we simulated oral, gastric, and small intestinal conditions. The analysis revealed differences in the microstructure, physicochemical properties, and protein digestibility between the plant-based scallops and real scallops. The particle size and charge followed the following similar trends for both types of scallops: the particle size decreased from the mouth to the stomach to the small intestine; the particles were negative in the mouth, positive in the stomach, and negative in the small intestine. The protein digestibility of the plant-based scallops was considerably lower than that of real scallops. For instance, around 18.8% and 61.4% of protein was digested in the stomach and small intestine phases for the real scallop (80.2% total digestion), whereas around 8.7% and 47.7% of the protein was digested for the plant-based scallop (56.4% total digestion). The lower digestibility of the plant-based scallops may have been due to differences in the protein structure, the presence of dietary fibers (pectin), or antinutritional factors in the plant proteins. These findings are crucial for developing more sustainable next-generation plant-based seafood analogs.

Dual role of polyglycerol vitamin E succinate in emulsions: An efficient antioxidant emulsifier.

α-Tocopherol, as an oil-soluble vitamin with strong antioxidant activity. It is the most naturally abundant and biologically active form of vitamin E in humans. In this study, a novel emulsifier (PG20-VES) was synthesized by attaching hydrophilic twenty-polyglycerol (PG20) to hydrophobic vitamin E succinate (VES). This emulsifier was shown to have a relatively low critical micelle concentration (CMC=3.2μg/mL). The antioxidant activities and emulsification properties of PG20-VES were compared with those of a widely used commercial emulsifier: D-α-Tocopherol polyethylene glycol 1000 succinate (TPGS). PG20-VES exhibited a lower interfacial tension, stronger emulsifying capacity and similar antioxidant property to TPGS. An in vitro digestion study showed that lipid droplets coated by PG20-VES were digested under simulated small intestine conditions. This study showed that PG20-VES is an efficient antioxidant emulsifier, which may have applications in the formulation of bioactive delivery systems in the food, supplement, and pharmaceutical industries.