Fermentation of Metroxylon sagu resistant starch type III by Lactobacillus sp. and Bifidobacterium bifidum

Chitin promotes equol production via n-acetylglucosamine in human fecal cultures

OBJECTIVES

Equol is a metabolite of isoflavone. Here, we investigated the effect of dietary fiber on equol-producing microbiota.

METHODS

Human feces was anaerobically cultured in Gifu Anaerobic Medium (GAM) containing 1 mg/L daidzein supplemented with 1 % (w/v) dietary fiber (pectin, chitin, or resistant starch [RS]). The equol conversion rate, number of equol-producing bacteria, pH, short-chain fatty acids (SCFAs), and microbial composition were measured in fecal cultures.

RESULTS

Equol conversion significantly increased by 2.7-fold in the chitin group compared with the control group. Conversely, the conversion rate decreased to one-tenth in the pectin group and one-third in the RS group. The number of equol-producing bacteria also significantly increased in the chitin group compared with the control group. Whereas pH values and acetate/propionate concentrations decreased in the pectin and RS groups compared with the control group, no significant differences were observed in the chitin group. Microbiota analysis indicated that the relative abundances of Bifidobacterium and Lactobacillus increased, whereas those of Dorea, Lachnoclostridium, and Eggerthella decreased in the pectin and RS groups. In contrast, these abundances remained stable in the chitin group. The relative abundances of Adlercreutzia and Slackia remained unchanged across all groups. In vitro cultures of Eggerthella sp. strain YY7918 and Adlercreutzia equolifaicens JCM14793 demonstrated that equol conversion from daidzein was stimulated by the addition of 0.5-1% (w/v) n-acetylglucosamine, a breakdown product of chitin, but not chitin itself.

CONCLUSIONS

Our findings suggest that equol production is stimulated by n-acetylglucosamine, derived from decomposed chitin, in certain equol-producing bacteria without affecting their growth.

Recent advances in sago (Metroxylon sagu) fibres, biopolymers, biocomposites, and their prospective applications in industry: A comprehensive review

Escalating petroleum depletion and environmental crises linked to conventional plastics have fueled interest in eco-friendly alternatives. Natural fibres and biopolymers are garnering increasing attention due to their sustainability. The sago palm (Metroxylon sagu), a tropical tree, holds potential for such materials, with cellulose-rich fibres (42.4-44.12 %) showcasing strong mechanics. Extracted sago palm starch can be blended, reinforced, or plasticised for improved traits. However, a comprehensive review of sago palm fibres, starch, and biocomposites is notably absent. This paper fills this void, meticulously assessing recent advancements in sago palm fibre, cellulose and starch properties, and their eco-friendly composite fabrication. Moreover, it uncovers the latent prospects of sago palm fibres and biopolymers across industries like automotive, packaging, and bioenergy. This review presents a crucial resource for envisaging and realising sustainable materials.

Metabolism of resistant starch RS3 administered in combination with Lactiplantibacillus plantarum strain 84-3 by human gut microbiota in simulated fermentation experiments in vitro and in a rat model

This study aimed to investigate the metabolic and population responses of gut microbiota to resistant starch (RS3) in the presence of exogenous Lactiplantibacillus plantarum strain 84-3 (Lp84-3) in vitro and in vivo. Lp84-3 promoted acetate, propionate, and butyrate production from RS3 by gut microbiota and increased Lactobacillus and Blautia contents in vitro. Furthermore, in the presence of Lp84-3, starch granules presented a "dot-by-hole" fermentation pattern. Administration of Lp84-3 with RS3 increased the level of SCFA-producing Faecalibaculum, Parabacteroides, Alistipes, and Anaeroplasma in the faeces of rates, with Lactobacillus and Akkermansia representing the key genera that significantly promoted SCFAs, especially propionate and butyrate. Lp84-3 with RS3 promoted genes related to tryptophan synthase (EC 4.2.1.20) and beta-glucosidase (EC 3.2.1.21) in faecal bacteria. Our findings highlight the ability of Lp84-3 to enhance RS3 degradation, possibly by promoting SCFA-producing bacteria, and indicate that Lp84-3 could be a potential probiotic with a beneficial effect on gut microbiota.

Effect of resistant starch types as a prebiotic

Since the role of intestinal microbiota in metabolism was understood, the importance of dietary components such as fibres and prebiotics, which affect the modulation of microbiota, has been increasing day by day. While all prebiotic components are considered dietary fibre, not every dietary fibre is considered a prebiotic. While fructooligosaccharides, galactooligosaccharides, inulin, and galactans are considered prebiotics, other fermentable carbohydrates are considered candidate prebiotic components based on in vitro and preclinical studies. Resistant starch, one of such carbohydrates, is considered a potential prebiotic component when it is made resistant to digestion naturally or chemically. In this review, both in vitro and in vivo studies in which the prebiotic capacity of type II, type III, and type IV resistant starch isolated from food and produced commercially was assessed were analyzed. According to the results of current studies, certain types of resistant starch are thought to have a high prebiotic capacity, and they may be candidate prebiotic components although positive results have not been achieved in all studies. KEY POINTS: • Resistant starch is undigested in the small intestine and is fermented in the large intestine. • Resistant starch fermentation positively affects the growth of Bifidobacterium and Lactobacillus. • Resistant starch can be considered a prebiotic ingredient.

Structural characteristics of locust bean gum hydrolysate and its alleviating effect on dextran sulfate sodium-induced colitis

Background

Ulcerative colitis (UC) is an inflammatory lesion of the colon from various causes. As current therapeutic drugs have adverse effects on patients with UC, there is a growing demand for alternative medicines from natural and functional foods. Locust bean gum, as a dietary fiber, has a variety of physiological effects.

Methods

In the present study, locust bean gum hydrolysate (LBGH) was obtained from the acid hydrolysis of locust bean gum. The structure of LBGH was characterized by thin-layer chromatography and high performance liquid chromatography (HPLC)-electrospray ionization (ESI)-mass spectrometry (MS)/MS analysis. And we investigated the therapeutic effect of LBGH on a mouse model of dextran sulfate sodium (DSS)-induced colitis.

Results

It was observed that the LBGH consisted of a mixture of monosaccharides and oligosaccharides with a degree of polymerization (DP) 2–7. LBGH treatment dramatically alleviated colonic pathological damage, suppressed the overproduction of pro-inflammatory factors and the activation of nuclear factor κB (NF-κB), increased the mRNA expression of tight junction proteins, and increased the abundance of probiotics such as Lactobacillus and Bifidobacterium in the gut.

Conclusion

There is a correlation between these mitigating effects on inflammation and the treatment of LBGH. Therefore, LBGH has tremendous potential in the treatment of colitis.

Influence of corn resistant starches type III on the rheology, structure, and viable counts of set yogurt

The study intended to explore the influence of corn resistant starches type III (RS3s) prepared by autoclave, debranching, and microwave heat on the rheology, structure, and viable counts of set yogurt. The rheological analysis suggested that RS3s enhanced the elastic and viscous modulus of yogurt, and that microwave-heated RS was the most effective for improving viscoelasticity. Fitting the creep data using the Burger model showed that yogurt with microwave-heated RS increased the structural strength of yogurt, which displayed the highest instantaneous and viscoelastic deformations. The confocal laser scanning microscopy and scanning electron microscopy micrographs demonstrated that autoclaved and debranched RS3s formed large fragments and disrupted the continuity of the milk protein structure; however, microwave-heated RS evenly filled the gel network and formed an interpenetrating network with proteins. The bacterial count and acidity of yogurt indicated that microwave-heated and debranched RS3s promoted the growth of lactic acid bacteria and accelerated the fermentation process of yogurt. The results of this study demonstrated that microwave-heated RS is a favorable supplement to the microstructure and rheological properties of yogurt compared with autoclaved and debranched RS3s.

The possible mechanism of the protective effect of a sulfated polysaccharide from Gracilaria Lemaneiformis against colitis induced by dextran sulfate sodium in mice

This study aimed to investigate the possible mechanism of the protective effect of a sulfated polysaccharide (SP) from Gracilaria Lemaneiformis against colitis induced by dextran sulfate sodium (DSS). Balb/c mice were gavaged with SP for four weeks, then colon tissue, cecal contents and feces were collected for further analysis. Results showed that SP was effective for inhibiting colon shortening and oedema forming. It could alleviate colonic inflammation via down-regulating the expression of tumor necrosis factor-α (TNF-α), interleukin (IL-6, IL-1β). Besides, it enhanced the intestinal barrier by up-regulating the expression of tight junction proteins Claudin-1 and Zonula occludens-1 (ZO-1) as well as Mucin (MUC-2). The increased expression of short chain fatty acid (SCFA) receptors including G protein-coupled receptor (GPR43, GPR109A) and olfactory receptor (Olfr78), and SCFA production in feces indicated that most of SCFA were absorbed in colon, which could play positive roles in ameliorating colitis. Furthermore, the results of gut microbiota showed that Enterorhabdus, Desulfovibrio, Alistipes, Bacteroides acidifaciens had closest correlations with the strongest protective effects against colitis. Therefore, SP could alleviate DSS-induced colitis via enhancing intestinal barrier, reducing inflammation, activating SCFA receptors and regulating gut microbiota. It could be developed as functional foods which is good for gut health.

Prebiotics from acorn and sago prevent high-fat-diet-induced insulin resistance via microbiome-gut-brain axis modulation

Role of gut microbiome in obesity and type 2 diabetes (T2D) became apparent from several independent studies indicating that gut microbiome modulators like prebiotics may improve microbiome perturbations (dysbiosis) to ameliorate metabolic derangements. We herein isolate water soluble, nondigestible polysaccharides from five plant-based foods (acorn, quinoa, sunflower, pumpkin seeds and sago) and assess their impact on human fecal microbiome and amelioration of high-fat-diet (HFD)-induced obesity/T2D in mice. During polysaccharide isolation, purification, biochemical and digestion resistance characterization, and fermentation pattern by human fecal microbiome, we select acorn- and sago-derived prebiotics (on the basis of relatively higher purity and yield and lower protein contamination) and examine their effects in comparison to inulin. Prebiotics treatments in human fecal microbiome culture system not only preserve microbial diversity but also appear to foster beneficial bacteria and short-chain fatty acids (SCFAs). Feeding of acorn- and sago-derived prebiotics ameliorates HFD-induced glucose intolerance and insulin resistance in mice, with effects comparatively superior to those seen in inulin-fed mice. Feeding of both of novel prebiotics as well as inulin increases SCFAs levels in the mouse gut. Interestingly, gut hyperpermeability and mucosal inflammatory markers were significantly reduced upon prebiotics feeding in HFD-fed mice. Hypothalamic energy signaling in terms of increased expression of pro-opiomelanocortin was also modulated by prebiotics administration. Results demonstrate that these (and/or such) novel prebiotics can ameliorate HFD-induced defects in glucose metabolism via positive modulation of gut-microbiome-brain axis and hence could be useful in preventing/treating diet-induced obesity/T2D.

Prebiotic effects of resistant starch from purple yam (Dioscorea alata L.) on the tolerance and proliferation ability of Bifidobacterium adolescentis in vitro

The in vitro prebiotic effects of resistant starch (RS), prepared by different treatments from purple yam, on Bifidobacterium adolescentis (bifidobacteria for short), were investigated. Tolerance tests indicated that bifidobacteria in PDS (prepared by debranching combined with autoclaving) and PDS.H (PDS further treated by double enzyme hydrolysis) media adapted better to simulated upper gastrointestinal conditions (at pH 1.5-3.0 and 0.3% and 1.0% bile acid) than those in GLU (glucose) and DAS (prepared by autoclaving) media. PDS.H, which had the highest digestion resistibility, exhibited significant effects on the OD600 nm value (1.544) and the pH value (4.21) when the carbohydrate concentration was 20 g L-1. Additionally, the exponential growth phase of bifidobacteria was 2 h in the PDS or PDS.H media, whereas it was 4 h in the GLU or DAS media. A higher content of short-chain fatty acids (SCFAs) was obtained in the PDS.H medium. Analysis of the structural features of RS and fermented RS indicated that PDS, especially PDS.H, had a rougher surface and higher crystallinity than DAS. Fermented RS in a simulated large bowel environment showed an eroded surface and decreased crystallinity. All of these findings suggest that RS with a rough surface and perfect crystalline structure could protect bifidobacteria from gastrointestinal conditions and enhance the proliferation of bifidobacteria.

In vitro activities of inulin fermentation products to HCT-116 cells enhanced by the cooperation between exogenous strains and adult faecal microbiota

Inulin was fermented by adult faecal microbiota and 10 exogenous strains for 24 or 48 h. The contents of acetate, propionate, butyrate and lactate were quantified in the fermented products, and the growth-inhibitory and apoptosis-inducing effects on a human colon cell line (HCT-116 cells) were assessed. Most of these strains increased contents of acetate, propionate and butyrate, and promoted lactate conversion. Correlation analysis suggested that butyrate and lactate in the fermentation products were positively and negatively correlated with the measured inhibition ratios (p < .05). The results were mostly consistent with the verification trial results using standard acid solutions. The fermentation products could cause apoptosis via inducing DNA fragmentation and increasing total apoptotic populations in the treated cells. Moreover, the fermentation products with higher growth-inhibitory activities demonstrated the increased apoptosis-inducing properties. In conclusion, these strains could cooperate with adult faecal microbiota to confer inulin fermentation products with higher anti-colon cancer activity.

Lotus Seed Resistant Starch Regulates Gut Microbiota and Increases Short-Chain Fatty Acids Production and Mineral Absorption in Mice

Lotus seed resistant starch, known as resistant starch type 3 (LRS3), was orally administered to mice to investigate its effects on the gut microbiota, short-chain fatty acids (SCFAs) production, and mineral absorption. The results showed that mice fed LRS3 displayed a lower level of gut bacterial diversity than other groups. The numbers of starch-utilizing and butyrate-producing bacteria, such as Lactobacillus and Bifidobacterium and Lachnospiraceae, Ruminococcaceae, and Clostridium, respectively, in mice increased after the administration of medium and high doses of LRS3, while those of Rikenellaceae and Porphyromonadaceae decreased. Furthermore, SCFAs and lactic acid in mice feces were affected by LRS3, and lactate was fermented to butyrate by gut microbiota. LRS3 enhanced the intestinal absorption of calcium, magnesium, and iron, and this was dependent on the type and concentration of SCFAs, especially butyrate. Thus, LRS3 promoted the production of SCFAs and mineral absorption by regulating gut microbiota in mice.

Probiotics or antibiotics: future challenges in medicine

Genetic and environmental factors can affect the intestinal microbiome and microbial metabolome. Among these environmental factors, the consumption of antibiotics can significantly change the intestinal microbiome of individuals and consequently affect the corresponding metagenome. The term 'probiotics' is related to preventive medicine rather than therapeutic procedures and is, thus, considered the opposite of antibiotics. This review discusses the challenges between these opposing treatments in terms of the following points: (i) antibiotic resistance, the relationship between antibiotic consumption and microbiome diversity reduction, antibiotic effect on the metagenome, and disease associated with antibiotics; and (ii) probiotics as living drugs, probiotic effect on epigenetic alterations, and gut microbiome relevance to hygiene indulgence. The intestinal microbiome is more specific for individuals and may be affected by environmental alterations and the occurrence of diseases.

Influences of exogenous probiotics and tea polyphenols on the production of three acids during the simulated colonic fermentation of maize resistant starch

In the present study, influences of nine probiotics and tea polyphenols on the production of acetic, butyric, and lactic acid from simulated colonic fermentation of maize resistant starch (RS) were investigated. RS was fermented by fecal extracts of healthy adults at 12 g L(-1) and 37 °C for 18-48 h in the presence and absence of exogenous probiotics and tea polyphenols. The added probiotics increased acetic and butyric acid production by 25-216 %. Eubacterium faecalis, Lactobacillus acidophilus, L. casei, and L. helveticus increased lactic acid production by 7-58 %; however, other probiotics decreased lactic acid production. Tea polyphenols facilitated lactic acid production but inhibited acetic and butyric acid production clearly. More importantly, the added probiotics weakened the inhibitory effects of tea polyphenols on the two acids, enhancing acetic and butyric acid production by 152-641 and 825-1,777 %, respectively. It is concluded that both probiotics and tea polyphenols have different impacts on the production of acetic, butyric and lactic acid during the colonic fermentation of RS. The impacts of other probiotics and food components on the colonic fermentation of RS and other dietary fibers should be investigated in future study to clarify their possible interactions.