A randomized trial to evaluate the impact of copra meal hydrolysate on gastrointestinal symptoms and gut microbiome

Enhancing gut microbiota and microbial function with inulin supplementation in children with obesity

BACKGROUND AND OBJECTIVES

Gut dysbiosis that resulted from the alteration between host-microbe interaction might worsen obesity-induced systemic inflammation. Gut microbiota manipulation by supplementation of prebiotic inulin may reverse metabolic abnormalities and improve obesity. This study aimed to determine whether inulin supplementation improved intestinal microbiota and microbial functional pathways in children with obesity.

METHODS

Children with obesity whose BMI above median + 2SDs were recruited to a randomized, double-blinded placebo-controlled study. The participants aged 7-15 years were assigned to inulin supplement extracted from Thai Jerusalem artichoke (intervention), maltodextrin (placebo), and dietary fiber advice groups. All participants received similar monthly conventional advice and follow-up for 6 months. Fecal samples were collected for gut microbiome analysis using 16S rRNA sequencing. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was performed to infer microbial functional pathways.

RESULTS

One hundred and forty-three children with available taxonomic and functional pathway abundance profiles were evaluated. A significant increase in alpha-diversity was observed in the inulin group. Inulin supplementation substantially enhanced Bifidobacterium, Blautia, Megasphaera, and several butyrate-producing bacteria, including Agathobacter, Eubacterium coprostanoligenes, and Subdoligranulum, compared to the other groups. The inulin group showed a significant difference in functional pathways of proteasome and riboflavin metabolism. These changes correlated with clinical and metabolic outcomes exclusively in the inulin group.

CONCLUSIONS

Inulin supplementation significantly promoted gut bacterial diversity and improved gut microbiota dysbiosis in children with obesity. The modulation of functional pathways by inulin suggests its potential to establish beneficial interactions between the gut microbiota and host physiology. Inulin supplementation could be a strategic treatment to restore the balance of intestinal microbiota and regulate their functions in childhood obesity.

Copra Meal: A Review of Its Production, Properties, and Prospects

Copra meal, the byproduct of coconut oil production, has been widely available at low cost but has been underutilized, with huge portions still becoming waste. Extensive research on different species have been performed to improve its use as an alternative feed ingredient, aiming to reduce the impact of fluctuating feed prices in some parts of the world where coconut is a major commodity. As for any biological product, the physical and chemical properties of copra meal play a crucial role in its use and limitations. In the case of copra meal, studies have found that additional treatments are needed to improve its nutritional composition and make it readily and efficiently available for ruminant and monogastric animals, poultry, and aquaculture applications. This paper presents a summary of up-to-date information on the physical and chemical characteristics of the product, as well as discussions on the various methods employed to improve and optimize its biological value as animal feed. There have been limited studies that have explored other effective and economical means of utilizing copra meal outside the livestock and feed industry. Hence, this paper also aims to provide a lens on future prospects and diverse applications involving copra meal, as well as to present the gaps and challenges that have to be addressed to maximize its product value and biological potential.

Simulated Swine Digestion and Gut Microbiota Fermentation of Hydrolyzed Copra Meal

This study aimed to compare the effects of hydrolyzed copra meal (HCM) inclusion at 1% on its in vitro digestibility and the microbiota and cecum fermentation using the gut microbiota of weaned swine, targeting microbial community and short-chain fatty acids (SCF). For this reason, three treatments were considered: control (no copra meal), 1% non-hydrolyzed copra meal (CM), and 1% HCM. Non-defatted copra meal was hydrolyzed and analyzed (reducing sugars and total carbohydrates) in our laboratory. For digestion, microbiota identification, and fermentation assays, fresh fecal samples from two weaned pigs (1 month old) were used. Three replicates of each treatment were employed. HCM was more digestible, with approximately 0.68 g of hydrolysate recovered after simulated digestion compared to 0.82 g of hydrolysate recovered from CM. This was shown by Scanning Electron Microscope (SEM) images. Also, the three swine shared the majority of microbial species identified at the phylum and family levels. There were no differences (p > 0.05) between treatments in the microbial community and SCFA during fermentation. However, higher Chao-1 and Shannon indexes were observed in CM and HCM treatments. HCM was also found to be capable of preserving Actinobacterota and Proteobacteria at the phylum level, while at the family level, both treatments may help Lactobacillaceae, Peptostreptococcaceae, Lachnospiraceae, and Ruminococcaceae survive in the long term. Also, there was a potential trend of increasing acetic acid and butyric acid in the CM and HCM treatments. While HCM shows promise in potentially modulating the gut microbiota of weaned swine, additional research is required to investigate the effects of higher doses of HCM on swine performance parameters.

Coffee oligosaccharides and their role in health and wellness

Coffee oligosaccharides (COS) are novel sources of prebiotics comprising manno-oligosaccharides, galacto-oligosaccharides, arabinoxylan-oligosaccharides, and cello-oligosaccharides. These oligosaccharides function as prebiotics, antioxidant-dietary fiber owing to important physicochemical and physiological properties, adjuvants, pharma, nutraceutical food, gut health, immune system boosting, cancer treatment, and many more. Research suggests COS performs prebiotic action, as it enhances gut health by promoting beneficial bacteria in the colon and releasing functional metabolites such as SCFAs. However, research on COS concerning other metabolic illnesses is still lacking. Among various production strategies, pretreatment and enzymatic hydrolysis are preferred for the production of COS. Functional oligosaccharides can add value to coffee waste and reduce the environmental impact of coffee manufacturing, besides providing more options for healthy and active ingredients. This review updates COS, production, bio-activity, their role as a functional food, food supplements/natural food additives, prebiotics and many applications of health sectors. Research is desirable to extend information on COS and their bio-activity, besides in vivo and clinical trials, to assess their effects in prior human formulations into the food and therapeutic arena.

Insect-based diets (house crickets and mulberry silkworm pupae): A comparison of their effects on canine gut microbiota

Background and Aim

The gut microbiome plays an important role in the overall health and well-being of dogs, influencing various physiological processes such as metabolism, nutrient absorption, and immune function. Edible insects are a sustainable and nutritious alternative protein source attracting increasing attention as a potential component of animal feeds, including pet food. However, little is known about the effects of insect-based diets on the gut microbiota of dogs. This study aimed to examine the fecal microbiota of dogs fed a diet that substituted common protein sources (poultry meal) with the house cricket (Acheta domesticus [AD]) or mulberry silkworm pupae (Bombyx mori pupae [BMp]) at different levels.

Materials and Methods

Fifteen healthy adult mixed-breed dogs were systemically randomized and assigned into each block under a completed randomized block design into the following five experimental dietary groups: control diet, 10% AD, 20% AD, 7% BMp, or 14% BMp for 29 days. The amounts fed to the dogs were based on the daily energy requirement. Fecal samples were collected on days 14 and 29 and analyzed for bacterial community structure using 16S ribosomal ribonucleic acid gene sequencing.

Results

At the phylum and genus levels, microbiota and their diversity were generally relatively similar among all treatments. The diets containing insects did not significantly alter the major phyla in the gut microbiome of dogs (p > 0.05). A few significant changes were found in the relative abundance of bacterial genera, with the levels of Allobaculum and Turicibacter being reduced in dogs fed a higher level of BMp. In contrast, only a decrease in Turicibacter was found in dogs fed the lower level of AD than the control diet (p < 0.05). Corynebacterium and Lactobacillus levels in the dogs fed 14% BMp were significantly increased compared with those in the control group (p < 0.05).

Conclusion

These findings suggest that insect-based diets may slightly alter the gut microbiota of dogs. Further research is needed to fully understand the mechanisms by which insect-based diets influence the gut microbiota of dogs and the long-term potential health implications.

Metabolic and inflammatory profiles, gut microbiota and lifestyle factors in overweight and normal weight young thai adults

Obesity among young adults, especially those living in developing countries is increasing. A high body mass index (BMI) is one of the major causes of several diseases worldwide, constituting an important risk factor for non-communicable diseases (NCDs). Investigations describing the relationship between BMI, clinical and gut microbiota characteristics and lifestyle factors of overweight young adults, especially from Southeast Asian countries are limited. Metabolic and inflammatory biomarkers, fecal microbiota profiles and lifestyle factors were compared between overweight Thai young adults (n = 30, mean age 33 ± 9.48) and those with normal weight (n = 30, mean age 27 ±7.50). This study was registered with the Thai Clinical Trials Registry (TCTR20220204007). Health status including body composition, fasting glucose and insulin, lipid profiles, liver and kidney function, inflammatory biomarkers, blood pressure and fecal microbiota using 16S rRNA gene sequencing data was determined. Dietary intake was assessed using a 3-day dietary record and a food frequency questionnaire (FFQ), with physical activity levels compared using the international physical activity questionnaire (IPAQ). The overweight group had significantly higher BMI, waist-hip ratio, body fat mass, % body fat, skeletal mass, triglyceride level, C-reactive protein, insulin and blood pressure, with lower levels of high-density lipoprotein cholesterol (HDL-C) and blood urea nitrogen compared to the normal weight group. Significant differences in fecal microbiota composition at the family and genus levels were observed between the two groups. In our clinical setting, we also observed that unhealthy diets with high consumption of food rich in fat and sugar, processed meat and alcohol, and physical inactivity were associated with an increased prevalence of overweight in Thai young adults. Results provided the big picture of health and lifestyle characteristics of overweight young Thai people. Young adults should be encouraged to engage in health-promoting activities that maintain healthy bodyweight.

Functional β-mannooligosaccharides: Sources, enzymatic production and application as prebiotics

One of the emerging non-digestible oligosaccharide prebiotics is β-mannooligosaccharides (β-MOS). β-MOS are β-mannan derived oligosaccharides, they are selectively fermented by gut microbiota, promoting the growth of beneficial microorganisms (probiotics), whereas the growth of enteric pathogens remains unaffected or gets inhibited in their presence, along with production of metabolites such as short-chain fatty acids. β-MOS also exhibit several other bioactive properties and health-promoting effects. Production of β-MOS using the enzymes such as β-mannanases is the most effective and eco-friendly approach. For the application of β-MOS on a large scale, their production needs to be standardized using low-cost substrates, efficient enzymes and optimization of the production conditions. Moreover, for their application, detailed in-vivo and clinical studies are required. For this, a thorough information of various studies in this regard is needed. The current review provides a comprehensive account of the enzymatic production of β-MOS along with an evaluation of their prebiotic and other bioactive properties. Their characterization, structural-functional relationship and in-vivo studies have also been summarized. Research gaps and future prospects have also been discussed, which will help in conducting further research for the commercialization of β-MOS as prebiotics, functional food ingredients and therapeutic agents.

Nondigestible Functional Oligosaccharides: Enzymatic Production and Food Applications for Intestinal Health

Nondigestible functional oligosaccharides are of particular interest in recent years because of their unique prebiotic activities, technological characteristics, and physiological effects. Among different types of strategies for the production of nondigestible functional oligosaccharides, enzymatic methods are preferred owing to the predictability and controllability of the structure and composition of the reaction products. Nondigestible functional oligosaccharides have been proved to show excellent prebiotic effects as well as other benefits to intestinal health. They have exhibited great application potential as functional food ingredients for various food products with improved quality and physicochemical characteristics. This article reviews the research progress on the enzymatic production of several typical nondigestible functional oligosaccharides in the food industry, including galacto-oligosaccharides, xylo-oligosaccharides, manno-oligosaccharides, chito-oligosaccharides, and human milk oligosaccharides. Moreover, their physicochemical properties and prebiotic activities are discussed as well as their contributions to intestinal health and applications in foods.

Analyzing Predominant Bacterial Species and Potential Short-Chain Fatty Acid-Associated Metabolic Routes in Human Gut Microbiome Using Integrative Metagenomics

Gut microbiome plays an essential role in host health, and there is interest in utilizing diet to modulate the composition and function of microbial communities. Copra meal hydrolysate (CMH) is commonly used as a natural additive to enhance health. However, the gut microbiome is largely unknown at species level and is associated with metabolic routes involving short-chain fatty acids (SCFAs). In this study, we aimed to analyze, using integrative metagenomics, the predominant species and metabolic routes involved in SCFAs production in the human gut microbiome after treatment with CMH. The effect of CMH treatment on the Thai gut microbiome was demonstrated using 16S rRNA genes with whole-metagenome shotgun (WMGS) sequencing technology. Accordingly, these results revealed that CMH has potentially beneficial effects on the gut microbiome. Twelve predominant bacterial species, as well as their potential metabolic routes, were involved in cooperative microbiome networks under sugar utilization (e.g., glucose, mannose, or xylose) and energy supply (e.g., NADH and ATP) in relation to SCFAs biosynthesis. These findings suggest that CMH may be used as a potential prebiotic diet for modulating and maintaining the gut microbiome. To our knowledge, this is the first study to reveal the predominant bacterial species and metabolic routes in the Thai gut microbiome after treatment with potential prebiotics.

Validity of food additive maltodextrin as placebo and effects on human gut physiology: systematic review of placebo-controlled clinical trials

PURPOSE

Maltodextrin (MDX) is a polysaccharide food additive commonly used as oral placebo/control to investigate treatments/interventions in humans. The aims of this study were to appraise the MDX effects on human physiology/gut microbiota, and to assess the validity of MDX as a placebo-control.

METHODS

We performed a systematic review of randomized-placebo-controlled clinical trials (RCTs) where MDX was used as an orally consumed placebo. Data were extracted from study results where effects (physiological/microbial) were attributed (or not) to MDX, and from study participant outcomes data, before-and-after MDX consumption, for post-publication 're-analysis' using paired-data statistics.

RESULTS

Of two hundred-sixteen studies on 'MDX/microbiome', seventy RCTs (n = 70) were selected for analysis. Supporting concerns regarding the validity of MDX as a placebo, the majority of RCTs (60%, CI 95% = 0.48-0.76; n = 42/70; Fisher-exact p = 0.001, expected < 5/70) reported MDX-induced physiological (38.1%, n = 16/42; p = 0.005), microbial metabolite (19%, n = 8/42; p = 0.013), or microbiome (50%, n = 21/42; p = 0.0001) effects. MDX-induced alterations on gut microbiome included changes in the Firmicutes and/or Bacteroidetes phyla, and Lactobacillus and/or Bifidobacterium species. Effects on various immunological, inflammatory markers, and gut function/permeability were also documented in 25.6% of the studies (n = 10/42). Notably, there was considerable variability in the direction of effects (decrease/increase), MDX dose, form (powder/pill), duration, and disease/populations studied. Overall, only 20% (n = 14/70; p = 0.026) of studies cross-referenced MDX as a justifiable/innocuous placebo, while 2.9% of studies (n = 2/70) acknowledged their data the opposite.

CONCLUSION

Orally-consumed MDX often (63.9% of RCTs) induces effects on human physiology/gut microbiota. Such effects question the validity of MDX as a placebo-control in human clinical trials.