In vitro digestion and fecal fermentation of highly resistant starch rice and its effect on the gut microbiota

Se-Pair Search for Deciphering Selenium-Encoded Peptide and a Pyrolysis-Thermolysis Dietary Model for Minimizing Loss of "KKSe(M)R" during Processing

Dietary deficiency of selenium is a global health hazard. Supplementation of organic selenopeptides via food crops is a relatively safe approach. Selenopeptides with heterogeneous selenium-encoded isotopes or a poorly fragmented peptide backbone remain unidentified in site-specific selenoproteomic analysis. Herein, we developed the Se-Pair Search, a UniProtKB-FASTA-independent peptide-matching strategy, exploiting the fragmentation patterns of shared peptide backbones in selenopeptides to optimize spectral interpretation, along with developing new selenosite assignment schemes (steps 1-3) to standardize selenium-localization data reporting for the selenoproteome community and thereby facilitating the discovery of unexpected selenopeptides. Using selenium-biofortified rice under cooking, fermentation, and high-temperature and high-pressure processing conditions as a pyrolysis-thermolysis dietary model, we probed the single-molecule-level kinetic evolution of the novel selenopeptide "KKSe(M)R" with qual-quantitative information on graph-theory-oriented localization calculations, abundance patterns, activation energy, and rate constants at a selenoproteome-wide scale. We ground-truth-annotated thirteen pyrolysis-thermolysis products and inferred four pyrolysis-thermolysis pathways to characterize the formation reactivity of the main intermediate variables of KKSe(M)R and constructed an advanced probe-type ultrasound technique prior to pyrolysis-thermolysis conditions for minimizing loss of KKSe(M)R during processing. Importantly, we reveal the unappreciated pyro-excitation diversion of KKSe(M)R at pyrolysis-thermolysis time and temperature matrices. These findings provide pioneering theoretical guidance for controlling dietary selenium supplementation within the safety thresholds.

Effect of lotus seed resistant starch on the bioconversion pathway of taurocholic acid by regulating the intestinal microbiota

Taurocholic acid (TCA) is abundant in the rat intestine and has multiple health benefits. In the gut, intestinal microbiota can transform TCA into different bile acid (BA) derivatives, with the composition of microbiota playing a crucial role in the transformation process. This study aims to investigate how lotus seed resistant starch (LRS) can regulate microbiota to influence BA transformation. A fecal fermentation study was conducted in vitro, using either LRS, high-amylose maize starch (HAMS), or glucose (GLU) to analyze microbiota composition, BA content, and metabolic enzyme activities over different fermentation times. Bioinformatics analysis found that LRS increased the relative abundance of Enterococcus, Bacillus, and Lactobacillus, and decreased Escherichia-Shigella, compared with HAMS and GLU. LRS also reduced total BA content and accelerated the conversion of TCA to cholic acid, deoxycholic acid, and other derivatives. These results reveal that LRS and GLU tend to mediate the dehydroxy pathway, whereas HAMS tends to secrete metabolic enzymes in the epimerization pathway. Therefore, the evidence that LRS may regulate TCA bioconversion may benefit human colon health research and provide an important theoretical basis, as well as offer new concepts for the development of functional foods.

Impact of Whey Protein Corona Formation around TiO2 Nanoparticles on Their Physiochemical Properties and Gastrointestinal Fate

Previously, we found that whey proteins form biomolecular coronas around titanium dioxide (TiO2) nanoparticles. Here, the gastrointestinal fate of whey protein-coated TiO2 nanoparticles and their interactions with gut microbiota were investigated. The antioxidant activity of protein-coated nanoparticles was enhanced after simulated digestion. The structure of the whey proteins was changed after they adsorbed to the surfaces of the TiO2 nanoparticles, which reduced their hydrolysis under simulated gastrointestinal conditions. The presence of protein coronas also regulated the impact of the TiO2 nanoparticles on colonic fermentation, including promoting the production of short-chain fatty acids. Bare TiO2 nanoparticles significantly increased the proportion of harmful bacteria and decreased the proportion of beneficial bacteria, but the presence of protein coronas alleviated this effect. In particular, the proportion of beneficial bacteria, such as Bacteroides and Bifidobacterium, was enhanced for the coated nanoparticles. Our results suggest that the formation of a whey protein corona around TiO2 nanoparticles may have beneficial effects on their behavior within the colon. This study provides valuable new insights into the potential impact of protein coronas on the gastrointestinal fate of inorganic nanoparticles.

New Horizons in Probiotics: Unraveling the Potential of Edible Microbial Polysaccharides through In Vitro Digestion Models

In vitro digestion models, as innovative assessment tools, possess advantages such as speed, high throughput, low cost, and high repeatability. They have been widely applied to the investigation of food digestion behavior and its potential impact on health. In recent years, research on edible polysaccharides in the field of intestinal health has been increasing. However, there is still a lack of systematic reviews on the application of microbial-derived edible polysaccharides in in vitro intestinal models. This review thoroughly discusses the limitations and challenges of static and dynamic in vitro digestion experiments, while providing an in-depth introduction to several typical in vitro digestion models. In light of this, we focus on the degradability of microbial polysaccharides and oligosaccharides, with a particular emphasis on edible microbial polysaccharides typically utilized in the food industry, such as xanthan gum and gellan gum, and their potential impacts on intestinal health. Through this review, a more comprehensive understanding of the latest developments in microbial polysaccharides, regarding probiotic delivery, immobilization, and probiotic potential, is expected, thus providing an expanded and deepened perspective for their application in functional foods.

Improvement of Urolithin A Yield by In Vitro Cofermentation of Streptococcus thermophilus FUA329 with Human Gut Microbiota from Different Urolithin Metabotypes

Streptococcus thermophilus FUA329 converts ellagic acid (EA) to urolithin A (Uro-A), which is not autonomously converted by the gut microbiota to produce highly bioavailable and multibiologically active Uro-A in urolithin metabotype 0 (UM-0) populations. We consider that Streptococcus thermophilus FUA329 has the potential to be developed as a probiotic. Therefore, we utilized S. thermophilus FUA329 for in vitro cofermentation with gut microbiota. The results revealed that strain FUA329 increased the production of EA-converted Uro-A during in vitro cofermentation with the human gut microbiota of different urolithin metabotypes (UMs), with a significant increase in the production of Uro-A in the experimental group of UM-0. In addition, changes in the in vitro cofermentation microbial community were determined using high-throughput sequencing. Strain FUA329 modulated the structure and composition of the gut microbiota in different UMs, thereby significantly increasing the abundance of beneficial microbiota in the gut microbiota while decreasing the abundance of harmful microbiota. Of greatest interest was the significant increase in the abundance of Actinobacteria phylum after the cofermentation of strain FUA329 with UM-0 gut microbiota, which might be related to the significant increase in the production of Uro-A.

Effects of In Vitro Fermentation of Polysialic Acid and Sialic Acid on Gut Microbial Community Composition and Metabolites in Healthy Humans

The influence of polysialic acid (PSA) and sialic acid (SA) on the gut microbial community composition and metabolites in healthy humans was investigated using a bionic gastrointestinal reactor. The results indicated that PSA and SA significantly changed the gut microbiota and metabolites to different degrees. PSA can increase the relative abundances of Faecalibacterium and Allisonella, whereas SA can increase those of Bifidobacterium and Megamonas. Both can significantly increase the content of short-chain fatty acids. The results of metabolome analysis showed that PSA can upregulate ergosterol peroxide and gallic acid and downregulate the harmful metabolite N-acetylputrescine. SA can upregulate 4-pyridoxic acid and lipoic acid. PSA and SA affect gut microbiota and metabolites in different ways and have positive effects on human health. These results will provide a reference for the further development of PSA- and SA-related functional foods and health products.

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.

In vitro gastrointestinal digestion methods of carbohydrate-rich foods

The trend toward healthier food products has led to an increase in the research of in vitro gastrointestinal digestion methods. Among the most used models, static models are the simplest. Most static models have three stages: oral, gastric, and intestinal, simulating the enzymatic, electrolyte, pH, temperature, and bile salt conditions. The studies that have taken the most notice are those related to antioxidant activity, followed by those dealing with proteins and carbohydrates using most of them static in vitro digestion models. The number of these studies has increased over the years, passing from 45 to 415 in a 10-year period (2012-2023) and showing an interest in knowing the impact of food on human health. Nevertheless, published papers report different methodologies and analytical approaches. This review discusses the similarities and differences between the published static in vitro gastrointestinal digestion methods, with a focus on carbohydrates, finding that the most used protocol is Infogest, but with differences, mainly in the type of enzymes and their activity. Regarding in vitro gastrointestinal digestion of carbohydrates, many of the published studies are related to food and biomacromolecules, being the oral phase the most omitted, while the intestinal phase in the most diverse. Other methodologies to study the intestinal phase have been recommended, but the number of in vitro digestion studies using these methodologies (RSIE and BBMV) is still scarce but could represent a good alternative to analyze carbohydrates foods when combining with Infogest. More studies are required in this area.

In vitro fermentation characteristics of blueberry anthocyanins and their impacts on gut microbiota from obese human

It has been demonstrated that the gut microbiota may play an important intermediary role in anthocyanins' beneficial impacts on obesity. However, the microbe-related anti-obesity mechanism of blueberry anthocyanins remains unclear. In this study, the interactions between blueberry anthocyanin extracts (BAE) and gut microbiota from obese humans were explored using an in vitro fermentation model. Due to hydrolysis and metabolism by the microbiota, the contents of blueberry anthocyanins are reduced during fermentation. It was demonstrated that both aglycones and glycosides affected the degradation rate. The microbial composition evaluation revealed that BAE could alleviate obesity by promoting the colonization of probiotics such as Lachnospiraceae_UCG-004 and Bacteroides, as well as inhibiting the proliferation of harmful bacteria including Escherichia-Shigella, Clostridium_sensu_stricto_1, and Klebsiella. Blueberry anthocyanin extracts facilitate the production of short-chain fatty acids (SCFAs), which is beneficial for obesity control. The relationship between blueberry anthocyanins, gut microbiota, and SCFAs was further investigated. Overall, this data provides new insights into the positive interaction between blueberry anthocyanins and gut microbiota in obese humans.

A Comprehensive Review of the Effects of Glycemic Carbohydrates on the Neurocognitive Functions Based on Gut Microenvironment Regulation and Glycemic Fluctuation Control

Improper glycemic carbohydrates (GCs) consumption can be a potential risk factor for metabolic diseases such as obesity and diabetes, which may lead to cognitive impairment. Although several potential mechanisms have been studied, the biological relationship between carbohydrate consumption and neurocognitive impairment is still uncertain. In this review, the main effects and mechanisms of GCs' digestive characteristics on cognitive functions are comprehensively elucidated. Additionally, healthier carbohydrate selection, a reliable research model, and future directions are discussed. Individuals in their early and late lives and patients with metabolic diseases are highly susceptible to dietary-induced cognitive impairment. It is well known that gut function is closely related to dietary patterns. Unhealthy carbohydrate diet-induced gut microenvironment disorders negatively impact cognitive functions through the gut-brain axis. Moreover, severe glycemic fluctuations, due to rapidly digestible carbohydrate consumption or metabolic diseases, can impair neurocognitive functions by disrupting glucose metabolism, dysregulating calcium homeostasis, oxidative stress, inflammatory responses, and accumulating advanced glycation end products. Unstable glycemic status can lead to more severe neurological impairment than persistent hyperglycemia. Slow-digested or resistant carbohydrates might contribute to better neurocognitive functions due to stable glycemic response and healthier gut functions than fully gelatinized starch and nutritive sugars.

The ratio of choline lysine ionic liquid determines the structure and digestion of starch-oleic acid complex

Fully green choline lysine ([Cho][Lys]) ionic liquid (IL) was explored as the solvent to prepare starch-fatty acid complex, and the regulation of water: [Cho][Lys] (W:IL) ratio on the structure and digestion of starch-oleic acid (OA) complex was illuminated. Compared with pure water (W:IL-10:0), high (W:IL-0:10) or low concentration (W:IL-8:2, 6:4) of [Cho][Lys] IL would inhibit the disaggregation behaviors of starch. This inhibition led to the preservation of more original ordered multi-structures of starch (indicated as more double helix, type A crystalline structures, denser aggregate structure and ΔH values of gelatinization peak) and less complexion of starch with OA (indicated as less single helix, type V crystalline structures). While in W:IL-4:6, 2:8 mixtures, the disaggregation behaviors of starch were much promoted, and the original multi-structures of starch were much destroyed, which would enhance the complexion of starch with OA to form higher contents of single helix and type II V crystalline structures. As results, the anti-digestibility of starch-OA complexes prepared in W:IL-4:6, 2:8 mixtures were much improved in paste form. These results provide a new way of using [Cho][Lys] solvents to improve the complexion of starch with fatty acid and to create starch-based functional foods.

Gut microbiota-metabolic axis insight into the hyperlipidemic effect of lotus seed resistant starch in hyperlipidemic mice

We investigated the hyperlipidemic effect of different doses of lotus seed resistant starch (low-, medium and high-dose LRS, named as LLRS, MLRS and HLRS, respectively) in hyperlipidemic mice using gut microbiota-metabolic axis compared to high-fat diet mice (model control group, MC). Allobaculum was significantly decreased in LRS groups compared to MC group, while MLRS promoted the abundance of norank_f_Muribaculaceae and norank_f_Erysipelotrichaceae. Moreover, supplementation of LRS promoted cholic acid (CA) production and inhibited deoxycholic acid compared to MC group. Among, LLRS promoted formic acid, MLRS inhibited 20-Carboxy-leukotriene B4, while HLRS promoted 3, 4-Methyleneazelaic acid and inhibited Oleic acid and Malic acid. Finally, MLRS regulate microbiota composition, and this promoted cholesterol catabolism to form CA, which inhibited serum lipid index by gut microbiota-metabolic axis. In conclusion, MLRS can promote CA and inhibit medium chain fatty acids, so as to play the best role in lowering blood lipids in hyperlipidemia mice.

Fermentation of resistant starch from the starch-ferulic acid inclusion complex compared with high-amylose corn starch

Fermentation of resistant starch from the starch-ferulic acid inclusion complex, one representative of the starch-polyphenol inclusion complex, was investigated in this study. It was found that this complex-based resistant starch, high-amylose corn starch and the mixture of ferulic acid and high-amylose corn starch were mainly utilized at the initial 6 h as indicated by the gas production and pH. Besides, the supplement of high-amylose corn starch, the mixture and the complex promoted production of short-chain fatty acids (SCFAs), reduced the ratio of Firmicutes/Bacteroidetes (F/B) and selectively stimulated the proliferation of some beneficial bacteria. Specifically, the production of SCFAs in the control and high-amylose starch, mixture and complex groups was 29.33 mM, 140.82 mM, 144.12 mM, and 167.4 mM after fermentation for 48 h, respectively. Moreover, the F/B ratio of those groups was 1.78, 0.78, 0.8 and 0.69, respectively. These results suggested that the supplement of the complex-based resistant starch led to the most SCFAs and the lowest F/B ratio (P < 0.05). Moreover, the complex group had the largest abundance of beneficial bacteria, including Bacteroides, Bifidobacterium and Lachnospiraceae_UCG-001 (P < 0.05). In summary, the resistant starch from the starch-ferulic acid inclusion complex exhibited stronger prebiotic activity than high-amylose corn starch and the mixture.

The contribution of cell wall integrity to gastric emptying and in vitro starch digestibility and fermentation performance of highland barley foods

Studies have shown that the structure, composition, and bioavailability of compounds in whole grains are affected by processing and the role of cells walls. In this study, the effects of different processing methods on highland barley, one of the mostly widely produced whole grains worldwide, were investigated. The processing methods applied were flaking-boiling (HB flake), sand-roasting (Puffed HB), and sand-roasting-milling (Tsamba). Results showed Puffed HB and Tsamba had higher levels of damaged starch content, starch short-range molecular order, and relative crystallinity than HB flake. The half-time of gastric emptying (t_1/2) was the slowest for Tsamba (132.3 min) compared to HB flake (122.5 min) and Puffed HB (84.0 min), indicating the slowest gastric emptying rate, which could be attributed to its high viscosity of gastric digesta. After in vitro gastroduodenal digestion, Puffed HB exhibited the lowest starch digestibility and the least amount of β-glucan due to its less damaged cellular structure. Furthermore, Puffed HB resulted in a 21% and 18% higher in vitro production of total short-chain fatty acids than Tsamba and HB flake, respectively. Besides, undigested starch of Puffed HB after in vitro gastroduodenal digestion delayed in vitro fecal fermentation of β-glucan. Our study provided insight into the potential mechanisms of how cell wall integrity affected the gastric emptying, in vitro starch digestibility, and in vitro fecal fermentation of highland barley foods.

In vitro fecal fermentation characteristics of mutant rice starch depend more on amylose content than crystalline structure

To obtain the relation between rice starch features and fermentation characteristics, rice starches with various polymorphic types and apparent amylose contents were subjected to in vitro fecal fermentation. Gas and short-chain fatty acid production was evaluated as a function of fermentation time, and the microbial responses were monitored by 16S rRNA sequencing technique at the end of fermentation. Regardless of polymorphic type, three high-amylose mutant rice starches (i.e., GM03, A-type; BP577, B-type; Wx21TT, C-type) displayed significantly slower fermentation rate during the first 12 h and higher final butyrate yield (17.6-17.9 mM) compared to the A-type normal starches (9311 and Wx22TT), and promoted the proliferation of Roseburia. However, A-type normal rice starches presented higher propionate production, and increased the growth of Bacteroides and Megamonas. The principal component and redundancy analyses indicated that three high-amylose mutant rice starches showed similar abundance and migration of microbial communities, and the apparent amylose content was closely correlated with the abundance of their five key amplicon sequence variants. Our results demonstrated that amylose content might be a controlling factor in determining the fermentation properties of rice starches than crystalline structure.

Interfacial Catalysis during Amylolytic Degradation of Starch Granules: Current Understanding and Kinetic Approaches

Enzymatic hydrolysis of starch granules forms the fundamental basis of how nature degrades starch in plant cells, how starch is utilized as an energy resource in foods, and develops efficient, low-cost saccharification of starch, such as bioethanol and sweeteners. However, most investigations on starch hydrolysis have focused on its rates of degradation, either in its gelatinized or soluble state. These systems are inherently more well-defined, and kinetic parameters can be readily derived for different hydrolytic enzymes and starch molecular structures. Conversely, hydrolysis is notably slower for solid substrates, such as starch granules, and the kinetics are more complex. The main problems include that the surface of the substrate is multifaceted, its chemical and physical properties are ill-defined, and it also continuously changes as the hydrolysis proceeds. Hence, methods need to be developed for analyzing such heterogeneous catalytic systems. Most data on starch granule degradation are obtained on a long-term enzyme-action basis from which initial rates cannot be derived. In this review, we discuss these various aspects and future possibilities for developing experimental procedures to describe and understand interfacial enzyme hydrolysis of native starch granules more accurately.

In Vitro Digestion and Fecal Fermentation of Low-Gluten Rice and Its Effect on the Gut Microbiota

Low-gluten rice is part of a special diet for chronic kidney disease patients, but its digestive mechanism in the gastrointestinal tract is unclear. In this study, low-gluten rice (LGR), common rice (CR), and rice starch (RS) were used as experimental samples, and their digestion and bacterial fermentation were simulated using an in vitro gastrointestinal reactor to investigate the mechanism of the effect of LGR on human health. The starch digestibility of CR was higher than that of LGR, with statistically significant differences. LGR has growth-promoting and metabolic effects on Akkermansia muciniphila. Among the beneficial metabolites, the concentration of short-chain fatty acids (SCFAs) from LGR reached 104.85 mmol/L, an increase of 44.94% (versus RS) and 25.33% (versus CR). Moreover, the concentration of lactic acid reached 18.19 mmol/L, an increase of 60.55% (versus RS) and 25.28% (versus CR). Among the harmful metabolites, the concentration of branched-chain fatty acids (BCFAs) in LGR was 0.29 mmol/L and the concentration of ammonia was 2.60 mmol/L, which was 79.31% and 16.15% lower than CR, respectively. A significant increase in the concentration of the beneficial intestinal bacteria Bacteroides and Bifidobacterium occurred from LGR. The 16s rDNA sequencing showed that the abundance of the Bacteroidetes and Firmicutes increased and the abundance of the Proteobacteria and Fusobacteria decreased. Thus, LGR has positive effects on digestion and gut microbiota structure and metabolism in humans.

Dietary spirulina supplementation modifies rumen development, fermentation and bacteria composition in Hu sheep when consuming high-fat dietary

Introduction

This study aims to investigate the long-term effects of spirulina supplementation in a high-fat diet (HFD) on rumen morphology, rumen fermentation, and the composition of rumen microbiota in lambs. Spirulina is a blue-green microalgae that has been shown to have high nutritional value for livestock.

Methods

Fifty-four lambs were randomly divided into three groups: a normal chow diet (NCD) group, a high-fat diet (HFD) group, and a high-fat diet supplemented with 3% spirulina (HFD+S) group. Rumen morphology, rumen fermentation, and rumen microbiota were analyzed at the end of the study.

Results

Spirulina supplementation improved the concentration of volatile fatty acids and rumen papilla length. Additionally, there was a tendency for an increase in rumen weight and an upregulation of the genes Claudin-1, Claudin-4, and Occludin in the HFD+S group. Pyrosequencing of the 16S ribosomal RNA gene also showed that spirulina supplementation significantly changed the rumen microbiota composition in the HFD group, with a decrease in richness and diversity. Specifically, the relative abundance of Prevotella 9 and Megasphaera was significantly increased in the HFD group compared to the NCD group, while spirulina supplementation reversed these changes.

Discussion

This study suggests that 3% spirulina supplementation can improve rumen development and fermentation, and effectively relieve rumen microbe disorders in lambs caused by a high-fat diet. However, further research is needed to confirm the findings and to examine the long-term effects of spirulina supplementation in different types of livestock and under different dietary conditions.

Simulated Digestion and Fermentation In Vitro by Obese Human Gut Microbiota of Sulforaphane from Broccoli Seeds

BACKGROUND

sulforaphane is a kind of isothiocyanate, which is obtained by hydrolysis of glucosinolate by the unique myrosinase in plants. It has been proved to prevent the occurrence of many chronic diseases, such as obesity, diabetes and cancer.

OBJECTIVE

The impact of SFN on obese human gut flora, however, has not been established.

METHODS

In this research, SFN was isolated from broccoli seeds and then refined to achieve 95% purity. Next, an investigation was conducted into the digestion and fermentation processes of SFN.

RESULTS

The stability of the SFN in simulated saliva, gastric fluid, and intestinal juice provides evidence that it can reach the gut and be available for utilization by gut microflora. In vitro fermentation of SFN by gut microbes in obese patients results in alteration in constitution of microbiota and production of short chain fatty acids. As the result of SFN ingestion by human gut bacteria, the content of butyric and valeric acids increased 1.21- and 1.46-fold, respectively. In obese human guts, the relative abundances of the beneficial genera including Lactobacillus, Weissella, Leuconosto, Algiphilus and Faecalibacterium significantly increased, whilst the detrimental genera, such as Escherichia-Shigella, Klebsiella, Clostridium_sensu_stricto_1, Sutterella, Megamonas and Proteus drastically declined.

CONCLUSION

Taken together, these findings demonstrate that SFN can be used as a nutraceutical ingredient for obese patients and for improving human health.

Aloe Vera-Fermented Beverage Ameliorates Obesity and Gut Dysbiosis in High-Fat-Diet Mice

Aloe vera has been proven to have various medicinal properties, including anti-inflammatory and anti-obesity functions. However, the effects of Aloe vera-fermented beverages (AFB) on obesity and its complications are still not clear. In this study, HepG2 cells in high-fat environment and high-fat diet (HFD) mice were used to investigate the potential obesity-preventing function of AFB. We found that AFB intervention decreased the amount of lipid droplets of HepG2 cells, suppressed the body weight gain and adipose accumulation, and reduced the serum contents of total cholesterol (TC), alanine aminotransferase (ALT), and interleukin 10 (IL-10) of HFD-mice. In addition, it also changed the composition of the gut microbiota. The ratio of Firmicutes/Bacteroidetes was decreased, while the relative abundance of Muribaculaceae, Alistipes and Rikenellaceae_RC9_gut_group was increased after the administration of AFB compared with HFD-mice. These results demonstrated that AFB can prevent diet-induced obesity (DIO) and provides a new option to modulate obesity-related gut dysbiosis.

Influence of Resistant Starch in Whole Rice on Human Gut Microbiota─From Correlation Implications to Possible Causal Mechanisms

Rice is the main staple food for a large population around the world, while it generally has a high glycemic index and low resistant starch (RS) content. Although many strategies have been applied to develop healthier rice products with increased RS contents, their actual effects on gut microbiota and human health remain elusive. In this review, currently available production methods of rice RS are briefly summarized, followed by a critical discussion on their interactions with gut microbiota and subsequent effects on human health, from correlation implications to causal mechanisms. Different contents, types, and structures of RS have been produced by strategies such as genetic manipulation and controlling cooking conditions. The difference can largely determine effects of rice RS on gut microbiota composition and metabolites by specific RS-gut microbiota interactions. This review can thus help the rice industry develop rice products with desirable RS contents and structures to generally improve human health.

The effects of high-fat foods on gut microbiota and small molecule intestinal gases: release kinetics and distribution in vitro colon model

Profiling intestinal gases and their responses to dietary changes can reveal the products and functions of the gut microbiota and their influence on human health. High-fat foods (HFF) can alter the gut microbiota and its metabolites, posing a potential health risk. However, little is known about the effects of HFF on intestinal gas distribution. Therefore, in this study, we used human fecal microorganisms as strains, an in vitro three-chamber colon model and an intestinal gas array sensor as tools. We performed in vitro fermentation using HFF as the fermentation substrate to reveal the effects of HFF on the kinetics of intestinal gas production and changes in the gut microbiota and its metabolites. We found that dietary fatty acids stimulated the production of H2S and volatile organic compounds in the colon, promoted Firmicutes abundance, and decreased Bacteroidetes abundance. These results highlight the potential role of HFF in altering the gut microbiota and intestinal gas, which can lead to health hazards.

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High-fat foods (HFF) can alter the gut microbiota and its metabolites.

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HFF stimulate H₂S and volatile organic compound production in the colon.

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Specific intestinal gases can be used as disease markers.

Octenyl Succinic Anhydride-Modified Starch Attenuates Body Weight Gain and Changes Intestinal Environment of High-Fat Diet-Fed Mice

Effects of octenylsuccinate (OS) starch on body composition and intestinal environment in high-fat diet-fed mice were investigated. C57BL/6J mice were treated with a regular-fat (RF) diet, a high-fat (HF) diet, or a high-fat diet supplemented with OS starch (HFOSS). Fecal short-chain fatty acids (SCFAs) were quantified using gas chromatography, and the fecal microbiota profile was analyzed by 16S rDNA sequencing. One-way ANOVA and metastats analysis were performed for statistical analysis. After 22 weeks of feeding, mice in the HFOSS group had significantly lower body weight, body fat, liver weight, and cumulative food intake than those in the HF group but higher than that of the RF group. Fecal total SCFA, acetic, propionic, and butyric acid concentrations were significantly higher in the HFOSS group than that in the HF and RF groups. OS starch intervention increased the relative abundance of Parabacteroides, Alistipes, and Ruminiclostridium_5 and decreased that of Tyzzerella, Oscillibacter, Desulfovibrio, and Anaerotruncus compared with the RF and HF groups. The relative abundance of Lachnospiraceae_UCG-006 in the HFOSS group was lower than that in the HF group but higher than that in the RF group. In conclusion, OS starch prevents fat accumulation in high-fat diet-fed mice and might provide potential health benefits due to its fermentability in the gut and its ability to regulate gut microbial community structure.

Effects of Marine Bioactive Compounds on Gut Ecology Based on In Vitro Digestion and Colonic Fermentation Models

Digestion and the absorption of food compounds are necessary steps before nutrients can exert a role in human health. The absorption and utilization of nutrients in the diet is an extremely complex dynamic process. Accurately grasping the digestion and absorption mechanisms of different nutrients or bioactive compounds can provide a better understanding regarding the relationship between health and nutrition. Several in vitro models for simulating human gastrointestinal digestion and colonic fermentation have been established to obtain more accurate data for further understanding of the metabolism of dietary components. Marine media is rich in a wide variety of nutrients that are essential for humans and is gaining increased attention as a research topic. This review summarizes some of the most explored in vitro digestion and colonic fermentation models. It also summarizes the research progress on the digestion and absorption of nutrients and bioactive compounds from marine substrates when subjected to these in vitro models. Additionally, an overview of the changes imparted by the digestion process on these bioactive compounds is provided, in order to support those marine resources that can be utilized for developing new healthy foods.

Intake of Natural, Unprocessed Tiger Nuts (Cyperus esculentus L.) Drink Significantly Favors Intestinal Beneficial Bacteria in a Short Period of Time

Horchata is a natural drink obtained from tiger nut tubers (Cyperus esculentus L.). It has a pleasant milky aspect and nutty flavor; some health benefits have been traditionally attributed to it. This study evaluated the effects of an unprocessed horchata drink on the gut microbiota of healthy adult volunteers (n = 31) who consumed 300 mL of natural, unprocessed horchata with no added sugar daily for 3 days. Although there were no apparent microbial profile changes induced by horchata consumption in the studied population, differences could be determined when volunteers were segmented by microbial clusters. Three distinctive enterogroups were identified previous to consuming horchata, respectively characterized by the relative abundances of Blautia and Lachnospira (B1), Bacteroides (B2) and Ruminococcus and Bifidobacterium (B3). After consuming horchata, samples of all volunteers were grouped into two clusters, one enriched in Akkermansia, Christenellaceae and Clostridiales (A1) and the other with a remarkable presence of Faecalibacterium, Bifidobacterium and Lachnospira (A2). Interestingly, the impact of horchata was dependent on the previous microbiome of each individual, and its effect yielded microbial profiles associated with butyrate production, which are typical of a Mediterranean or vegetable/fiber-rich diet and could be related to the presence of high amylose starch and polyphenols.

Physicochemical characterization, adsorption function and prebiotic effect of chitin-glucan complex from mushroom Coprinus comatus

Chitin-glucan complex (CGC) is a novel insoluble dietary fiber with multiple physiological activities. In this work, CGC was extracted from the fruiting body of Coprinus comatus and its physicochemical properties and prebiotic effects were investigated. The results indicated that CGC consisted of glucosamine and glucose in a molar ratio of 67: 33 with degree of acetylation of 61.91% and crystallinity index of 25.40%. The maximum degradation temperature was determined to be 307.52 °C, and a woven fibrous structure was observed by scanning electron microscopy. CGC exhibited higher oil-holding capacity, water-holding capacity and nitrite ion adsorption capacity than commercial chitin, and showed potential prebiotic effects. Compared with control and commercial chitin, CGC significantly (P < 0.05) increased the concentration of propionic and butyric acids. These results suggested that CGC from C. comatus was promising to be an alternative source of CGC products and used as a bioactive ingredient in functional foods.

New definition of resistant starch types from the gut microbiota perspectives - a review

Current definition of resistant starch (RS) types is largely based on their interactions with digestive enzymes from human upper gastrointestinal tract. However, this is frequently inadequate to reflect their effects on the gut microbiota, which is an important mechanism for RS to fulfill its function to improve human health. Distinct shifts of gut microbiota compositions and alterations of fermented metabolites could be resulted by the consumption of RS from the same type. This review summarized these defects from the current definitions of RS types, while more importantly proposed pioneering concepts for new definitions of RS types from the gut microbiota perspectives. New RS types considered the aspects of RS fermentation rate, fermentation end products, specificity toward gut microbiota and shifts of gut microbiota caused by the consumption of RS. These definitions were depending on the known outcomes from RS-gut microbiota interactions. The application of new RS types in understanding the complex RS-gut microbiota interactions and promoting human health should be focused in the future.

The nutritional profile and human health benefit of pigmented rice and the impact of post-harvest processes and product development on the nutritional components: A review

Pigmented rice has attracted considerable attention due to its nutritional value, which is in large conferred by its abundant content of phenolic compounds, considerable micronutrient concentrations, as well as its higher resistant starch and thereby slower digestibility properties. A wide range of phenolic compounds identified in pigmented rice exhibit biological activities such as antioxidant activity, anti-inflammatory, anticancer, and antidiabetic properties. Post-harvest processes significantly reduce the levels of these phytochemicals, but recent developments in processing methods have allowed greater retention of their contents. Pigmented rice has also been converted to different products for food preservation and to derive functional foods. Profiling a large set of pigmented rice cultivars will thus not only provide new insights into the phytochemical diversity of rice and the genes underlying the vast array of secondary metabolites present in this species but also provide information concerning their nutritional benefits, which will be instrumental in breeding healthier rice. The present review mainly focuses on the nutritional composition of pigmented rice and how it can impact human health alongside the effects of post-harvest processes and product development methods to retain the ambient level of phytochemicals in the final processed form in which it is consumed.