Coffee mannooligosaccharides, consumed as part of a free-living, weight-maintaining diet, increase the proportional reduction in body volume in overweight men

Prospective Associations between Dietary Patterns and Abdominal Obesity in Middle-Aged and Older Korean Adults

This study aimed to identify major dietary patterns associated with abdominal obesity in middle-aged and older Korean adults. Data from the Korean Genome and Epidemiology Study were used. A total of 48,037 Korean adults aged ≥40 years without abdominal obesity at baseline were followed-up. Dietary assessment was conducted using a validated 106-item food-frequency questionnaire, and dietary patterns were identified using factor analysis. Abdominal obesity was defined as a waist circumference of ≥90 cm for men and ≥85 cm for women, according to the Korean Society for the Study of Obesity. Multivariable Cox proportional-hazards models were used to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) for the future risk of abdominal obesity for each dietary pattern after adjusting for potential covariates. After an average follow-up of 4.89 years, we reported 5878 cases (1932 men and 3946 women) of abdominal obesity. Based on factor analysis, three major dietary patterns were identified in both men and women: the "healthy", "coffee and sweets", and "multi-grain" patterns. In the fully adjusted model, the "healthy" pattern was inversely associated with the incidence of abdominal obesity (HR for fourth vs. first quartile: 0.86; 95% CI: 0.75-0.98; p for trend = 0.0358 for men; HR for fourth vs. first quartile: 0.90; 95% CI: 0.83-0.99; p for trend = 0.0188 for women), whereas the "coffee and sweets" pattern was positively associated with it (HR for fourth vs. first quartile: 1.23; 95% CI: 1.08-1.40; p for trend = 0.0495 for men; HR for fourth vs. first quartile: 1.14; 95% CI: 1.04-1.25; p for trend = 0.0096 for women). In contrast, the "multi-grain" pattern in men and women showed no significant association with the incidence of abdominal obesity. Diets rich in colorful vegetables, seaweeds, mushrooms, tubers, fruits, soy products, and fish and low in coffee, sweets, and oils/fats might be favorable for reducing the future risk of abdominal obesity, particularly in middle-aged and older Korean adults.

Manno-oligosaccharides from cassia seed gum ameliorate inflammation and improve glucose metabolism in diabetic rats

Functional oligosaccharides show anti-diabetic effects through inflammation regulation with improved glucose metabolism. In this study, novel prebiotics of manno-oligosaccharides from cassia seed gum (CMOS) were incorporated into the diet of streptozotocin (STZ) plus high-fat and high-sugar diet (HFSD)-induced rats. After feeding for 8 weeks, CMOS (300-1200 mg per kg b.w. per d) significantly ameliorated the fasting blood glucose level (7.1-8.2 mmol L^-1) as compared with that of the model group (14.2 mmol L^-1), where the area under the oral glucose tolerance test curve was decreased by 20.0%-24.5%. Meanwhile, CMOS prevented STZ plus HFSD-induced damage to islet tissue with a clear and integrated morphology and reduced the glucagon/insulin area ratio (by 97.9% for 300 mg per kg b.w. per d CMOS). CMOS also reduced metabolic endotoxemia and maintained intestinal integrity with recovered mRNA expression of Zo-1 and occludin to the normal comparable level. Upon 16S rDNA sequencing, it was found that CMOS regulated the microbiota composition in the cecum with an increased relative abundance of Bifidobacteria, while that of Shigella was decreased. The molecular mechanisms involved in the anti-diabetic effects of CMOS were further studied. CMOS reduced the mRNA expression of Tlr2 and Tlr4 in the intestines of STZ plus HFSD-induced rats. Meanwhile, Nlrp3 associated inflammasome activation in the intestine and liver with glucose metabolism disorder was inhibited by CMOS, resulting in reduced interleukin-1β secretion (by 38.8-46.4% for CMOS of 300-1200 mg per kg b.w. per d) and inflammation. Furthermore, CMOS regulated the AKT/IRS/AMPK signaling pathway and improved glucose metabolism in the liver. Findings obtained here implicated that CMOS could modulate metabolic-inflammation as a functional dietary supplement.

Coffea arabica bean extract inhibits glucose transport and disaccharidase activity in Caco-2 cells

The major constituents of Coffea arabica (coffee), including caffeine, chlorogenic acid and caffeic acid, exhibit antihyperglycemic properties in in vitro and in vivo models. However, whether Coffea arabica bean extract (CBE) regulates glucose uptake activity and the underlying mechanisms involved remain unclear. The aim of the present study was to examine the effects of CBE on glucose absorption and identify the mechanisms involved using an in vitro model. The uptake of a fluorescent glucose analog into Caco-2 colorectal adenocarcinoma cells was determined. The expression levels of sodium glucose co-transporter 1 (SGLT1) and glucose transporter 2 (GLUT2) were evaluated. In addition, glycoside hydrolase enzyme activity was investigated. It was observed that CBE inhibited disaccharidase enzyme activity. Furthermore, CBE exerted an inhibitory effect on intestinal glucose absorption by downregulating SGLT1- and GLUT2-mediated 5' AMP-activated protein kinase phosphorylation and suppressing hepatocyte nuclear factor 1α expression. These data suggest that CBE may attenuate glucose absorption and may have potentially beneficial antihyperglycemic effects in the body; however, the mechanisms underlying the effects of CBE must be elucidated through further investigation.

The effects of nondigestible fermentable carbohydrates on adults with overweight or obesity: a meta-analysis of randomized controlled trials

CONTEXT

Nondigestible fermentable carbohydrates (NDFCs) can be fermented by microbiota, thereby yielding metabolites that have a beneficial role in the prevention and treatment of obesity and its complications. However, to our knowledge, no meta-analysis has been conducted to evaluate the effects of NDFCs on obesity.

OBJECTIVE

To conduct a meta-analysis of randomized controlled trials (RCTs) to summarize existing evidence on the effects of numerous NDFCs on adiposity and cardiovascular risk factors in adults with overweight or obesity with ≥2 weeks of follow-up.

DATA SOURCES

The following databases were searched: MEDLINE, Embase, and CINAHL.

DATA EXTRACTION

Seventy-seven RCTs with 4535 participants were identified for meta-analysis from the 3 databases.

DATA ANALYSIS

The findings suggest that increased intake of NDFCs is significantly effective in reducing body mass index by 0.280 kg/m2, weight by 0.501 kg, hip circumference by 0.554 cm, waist circumference by 0.649 cm, systolic blood pressure by 1.725 mmHg, total cholesterol by 0.36 mmol/L, and low-density lipoprotein by 0.385 mmol/L, with evidence of moderate-to-high quality.

CONCLUSION

Convincing evidence from meta-analyses of RCTs indicates that increased NDFC intake improves adiposity, blood lipid levels, and systolic blood pressure in people with overweight and obesity.

Applications of Microbial β-Mannanases

Mannans are main components of hemicellulosic fraction of softwoods and they are present widely in plant tissues. β-mannanases are the major mannan-degrading enzymes and are produced by different plants, animals, actinomycetes, fungi, and bacteria. These enzymes can function under conditions of wide range of pH and temperature. Applications of β-mannanases have therefore, been found in different industries such as animal feed, food, biorefinery, textile, detergent, and paper and pulp. This review summarizes the most recent studies reported on potential applications of β-mannanases and bioengineering of β-mannanases to modify and optimize their key catalytic properties to cater to growing demands of commercial sectors.

Prebiotic mannooligosaccharides: Synthesis, characterization and bioactive properties

Functional oligosaccharides are non-digestible food ingredients that confer numerous health benefits. Among these, mannooligosaccharides (MOS) are emerging prebiotics that have characteristic potential bio-active properties. Microbial mannanases can be used to break down mannan rich agro-residues to yield MOS. Various applications of MOS as health promoting functional food ingredient may open up newer opportunities in food and feed industry. Enzymatic hydrolysis is the widely preferred method over chemical hydrolysis for MOS production. Presently, commercial MOS is being derived from yeast cell wall mannan and is widely used as prebiotic in feed supplements for poultry and aquaculture. Apart from stimulating the growth of probiotic microflora, MOS impart anticancer and immunomodulatory effects by inducing different gene markers in colon cells. This review summarizes recent developments and future prospects of enzymatic synthesis of MOS from various mannans, their structural characteristics and their potential health benefits.

Development of an advanced integrative process to create valuable biosugars including manno-oligosaccharides and mannose from spent coffee grounds

Spent coffee grounds (SCG) or coffee residue wastes (CRW) provide excellent raw material for mannose and bioethanol production. In this study, SCG were used to produce valuable biosugars, including oligosaccharides (OSs), manno-oligosaccharides (MOSs), mannose, and bioethanol. SCG were subjected to delignification and defatting, producing SCG-derived polysaccharides. Two-stage enzymatic hydrolysis (short- and long-term) was performed to produce short-chain manno-oligosaccharides (MOSs) and monosaccharides (MSs), respectively. From 100 g dry weight (DW) amounts of SCG, approximately 77 g delignified SCG and 61 g SCG-derived polysaccharides, amounts of 15.9 g of first biosugars (mostly MOSs), 25.6 g of second biosugars (mostly MSs), and 3.1 g of bioethanol, were recovered. This technique may aid in the production of high-value mannose and OSs from SCG and other lignocellulosic biomasses that contain specific polysaccharides.

Effects of isolated soluble fiber supplementation on body weight, glycemia, and insulinemia in adults with overweight and obesity: a systematic review and meta-analysis of randomized controlled trials

Background: There is strong epidemiologic evidence that dietary fiber intake is protective against overweight and obesity; however, results of intervention studies have been mixed. Soluble fiber beneficially affects metabolism, and fiber supplementation may be a feasible approach to improve body composition and glycemia in adults with overweight and obesity.Objective: We evaluated randomized controlled trials (RCTs) of isolated soluble fiber supplementation in overweight and obese adults on outcomes related to weight management [body mass index (BMI; in kg/m²), body weight, percentage of body fat, and waist circumference] and glucose and insulin metabolism (homeostasis model assessment of insulin resistance and fasting insulin) through a systematic review and meta-analysis.Design: We searched PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature and Cochrane Library databases. Eligible studies were RCTs that compared isolated soluble fiber with placebo treatments without energy-restriction protocols. Random-effects models were used to estimate pooled effect sizes and 95% CIs. Meta-regressions were performed to assess outcomes in relation to the intervention duration, fiber dose, and fiber type. Publication bias was assessed via Begg's and Egger's tests and funnel plot inspection.Results: Findings from 12 RCTs (n = 609 participants) from 2 to 17 wk of duration are summarized in this review. Soluble fiber supplementation reduced BMI by 0.84 (95% CI: -1.35, -0.32; P = 0.001), body weight by 2.52 kg (95% CI: -4.25, -0.79 kg; P = 0.004), body fat by 0.41% (95% CI: -0.58%, -0.24%; P < 0.001), fasting glucose by 0.17 mmol/L (95% CI: -0.28, -0.06 mmol/L; P = 0.002), and fasting insulin by 15.88 pmol/L (95% CI: -29.05, -2.71 pmol/L; P = 0.02) compared with the effects of placebo treatments. No publication bias was identified. Considerable between-study heterogeneity was observed for most outcomes.Conclusions: Isolated soluble fiber supplementation improves anthropometric and metabolic outcomes in overweight and obese adults, thereby indicating that supplementation may improve fiber intake and health in these individuals. However, the interpretation of these findings warrants caution because of the considerable between-study heterogeneity. This trial was registered at clinicaltrials.gov as NCT03003897.

Effects of dietary fibre type on blood pressure: a systematic review and meta-analysis of randomized controlled trials of healthy individuals

OBJECTIVE

To determine the effect of different types of dietary fibre on SBP and DBP.

METHODS

A systematic review of the literature and a meta-analysis of randomized controlled trials using random-effects models. Eligibility criteria for studies included randomized controlled trials of at least 6 weeks duration, testing a fibre isolate or fibre-rich diet against a control or placebo published between 1 January 1990 and 1 December 2013.

RESULTS

Twenty-eight trials met the inclusion criteria and reported fibre intake and SBP and/or DBP. Eighteen trials were included in a meta-analysis. Studies were categorized into 1 of 12 fibre-type categories. The pooled estimates for all fibre types were -0.9 mmHg [95% confidence interval (CI) -2.5 to 0.6 mmHg] and -0.7 mmHg (95% CI -1.9 to 0.5 mmHg) for SBP and DBP, respectively. The median difference in total fibre was 6 g. Analyses of specific fibre types concluded that diets rich in beta-glucans reduce SBP by 2.9 mmHg (95% CI 0.9 to 4.9 mmHg) and DBP by 1.5 mmHg (95% CI 0.2 to 2.7 mmHg) for a median difference in beta-glucans of 4 g. Heterogeneity for individual fibre types was generally low.

CONCLUSIONS

Higher consumption of beta-glucan fibre is associated with lower SBP and DBP. The results of this review are consistent with recommendations to increase consumption of foods rich in dietary fibre, but some additional emphasis on sources of beta-glucans, such as oats and barley, may be warranted.

The study of interactions between active compounds of coffee and willow (Salix sp.) bark water extract

Coffee and willow are known as valuable sources of biologically active phytochemicals such as chlorogenic acid, caffeine, and salicin. The aim of the study was to determine the interactions between the active compounds contained in water extracts from coffee and bark of willow (Salix purpurea and Salix myrsinifolia). Raw materials and their mixtures were characterized by multidirectional antioxidant activities; however, bioactive constituents interacted with each other. Synergism was observed for ability of inhibition of lipid peroxidation and reducing power, whereas compounds able to scavenge ABTS radical cation acted antagonistically. Additionally, phytochemicals from willow bark possessed hydrophilic character and thermostability which justifies their potential use as an ingredient in coffee beverages. Proposed mixtures may be used in the prophylaxis or treatment of some civilization diseases linked with oxidative stress. Most importantly, strong synergism observed for phytochemicals able to prevent lipids against oxidation may suggest protective effect for cell membrane phospholipids. Obtained results indicate that extracts from bark tested Salix genotypes as an ingredient in coffee beverages can provide health promoting benefits to the consumers; however, this issue requires further study.

Bioactive micronutrients in coffee: recent analytical approaches for characterization and quantification

Production of coffee beans is an important lifeline for the economy of several countries in Latin America, Africa, and Asia. The brew from this well sought for cash crop is readily consumed due to its good sensory qualities owing to the presence of many micronutrients. Some of these chemical compounds possess biological activities, including antiproliferative, antioxidant, and antimicrobial effects. Four representative groups of these micronutrients, namely, caffeine, chlorogenic acid, diterpenes, and trigonelline, play key roles in these bioactive effects of coffee. In order to guarantee the quality of coffee products and to protect consumer interest and safeguard their well-being, it is extremely important to employ sensitive and accurate analytical methods in the characterization and quantitative determination of these bioactive constituents. This review aims to present recent applications in this regard.

Role of glycoside phosphorylases in mannose foraging by human gut bacteria

To metabolize both dietary fiber constituent carbohydrates and host glycans lining the intestinal epithelium, gut bacteria produce a wide range of carbohydrate-active enzymes, of which glycoside hydrolases are the main components. In this study, we describe the ability of phosphorylases to participate in the breakdown of human N-glycans, from an analysis of the substrate specificity of UhgbMP, a mannoside phosphorylase of the GH130 protein family discovered by functional metagenomics. UhgbMP is found to phosphorolyze β-D-Manp-1,4-β-D-GlcpNAc-1,4-D-GlcpNAc and is also a highly efficient enzyme to catalyze the synthesis of this precious N-glycan core oligosaccharide by reverse phosphorolysis. Analysis of sequence conservation within family GH130, mapped on a three-dimensional model of UhgbMP and supported by site-directed mutagenesis results, revealed two GH130 subfamilies and allowed the identification of key residues responsible for catalysis and substrate specificity. The analysis of the genomic context of 65 known GH130 sequences belonging to human gut bacteria indicates that the enzymes of the GH130_1 subfamily would be involved in mannan catabolism, whereas the enzymes belonging to the GH130_2 subfamily would rather work in synergy with glycoside hydrolases of the GH92 and GH18 families in the breakdown of N-glycans. The use of GH130 inhibitors as therapeutic agents or functional foods could thus be considered as an innovative strategy to inhibit N-glycan degradation, with the ultimate goal of protecting, or restoring, the epithelial barrier.

Effect of different amounts of coffee on dietary intake and appetite of normal-weight and overweight/obese individuals

OBJECTIVE

To investigate the effects of different coffee amounts on dietary intake and appetite feelings in normal-weight and overweight/obese individuals.

DESIGN AND METHODS

Thirty-three volunteers (16 normal-weight, 17 overweight/obese) participated in three trials: they consumed a standard breakfast along with 200 ml of either coffee with 3 or 6 mg caffeine/kg body weight (Coffee 3 and Coffee 6, respectively), or water. At fasting and at standard time points for the 3 h following breakfast/drink consumption participants recorded their appetite feelings on visual analogue scales. At 180 min, participants consumed an ad libitum meal and the next day they recalled their food intake during the experimental day.

RESULTS

A significant intervention effect was found for the energy intake of the ad libitum meal (P = 0.05) and of the whole day (P = 0.02) only in overweight/obese individuals. Specifically, Coffee 6 resulted in a reduced energy intake during the ad libitum meal compared to Coffee 3 (P = 0.03) and in the total day compared to both water (P = 0.04) and Coffee 3 (P = 0.008). No effect was observed for the appetite feelings.

CONCLUSIONS

A moderate coffee amount can effectively reduce energy intake in the following meal and in the total day compared to lower or no coffee intake in overweight/obese participants.

A weight-loss diet including coffee-derived mannooligosaccharides enhances adipose tissue loss in overweight men but not women

Mannooligosaccharides (MOS), extracted from coffee, have been shown to promote a decrease in body fat when consumed as part of free-living, weight-maintaining diets. Our objective was to determine if MOS consumption (4 g/day), in conjunction with a weight-loss diet, would lead to greater reductions in adipose tissue compartments than placebo. We conducted a double-blind, placebo-controlled weight-loss study in which 60 overweight men and women consumed study beverages and received weekly group counseling for 12 weeks. Weight and blood pressure were measured weekly, and adipose tissue distribution was assessed at baseline and at end point using magnetic resonance imaging. A total of 54 subjects completed the study. Men consuming the MOS beverage had greater loss of body weight than men consuming the Placebo beverage (-6.0 ± 0.6% vs. -2.3 ± 0.5%, respectively, P < 0.05). Men consuming the MOS beverage also had reductions in total body volume (P < 0.0001), total (P < 0.0001), subcutaneous (P < 0.0001), and visceral (P < 0.05) adipose tissue that were greater than changes observed in those consuming the Placebo beverage. In women, changes in body weight and adipose tissue compartments were not different between groups. Adding coffee-derived MOS to a weight-loss diet enhanced both weight and adipose tissue losses in men, suggesting a potential functional use of MOS for weight management and improvement in adipose tissue distribution. More studies are needed to investigate the apparent gender difference in response to MOS consumption.