Relationships between diet and gut microbiome in an Italian and Dutch cohort: does the dietary protein to fiber ratio play a role?

PURPOSE: To investigate the relationships between the habitual diet, the protein to fiber ratio (P/F), and the gut microbiome in one Italian and one Dutch cohort of healthy subjects consuming an omnivore diet. METHODS: The Italian cohort included 19 males (M_IT, BMI 25.2 ± 0.72 kg/m2, age 25.4 ± 0.96 years) and 20 females (F_IT, BMI 23.9 ± 0.81 kg/m2, age 23.8 ± 0.54 years); the Dutch cohort included 30 females (F_NL, BMI: 23.9 ± 0.81 kg/m2, age: 23.8 ± 0.54 years). Individual diets were recorded through Food Frequency Questionnaires and analyzed to assess the nutrient composition. Gut microbiome was assessed in fecal samples. RESULTS: M_IT consumed higher levels of proteins than F_NL and F_IT, whereas dietary fiber intake did not differ among groups. Data showed that consumption of plant protein to animal protein (PP/AP) and PP to total proteins ratio can determine a differentiation of F_NL more than the absolute amount of dietary fiber. Conversely, the protein to fiber (P/F) and AP to total proteins better characterized M_IT. M_IT harbored the highest abundance of proteolytic microorganisms and the lowest microbial gene richness. Conversely, F_NL had more fiber-degrading microorganisms like Bacteroides thetaiotaomicron, Bacteroides xylanisolvens, Roseburia sp., Coprococcus eutactus and Parabacteroides along with the highest number of genes encoding carbohydrate-active enzymes and gene richness. It was predicted that by each unit decrease in the P/F a 3% increase in gene richness occurred. CONCLUSION: Study findings suggested that dietary P/F, rather than the absolute amount of dietary fiber, could contribute to the shaping of the microbiome towards a more proteolytic or fiber-degrading gut ecosystem. CLINICALTRIALS: gov Identifier NCT04205045-01-10-2018, retrospectively registered. Dutch Trial Register NTR7531-05-10-2018.

Baobab-Fruit Shell and Fibrous Filaments Are Sources of Antioxidant Dietary Fibers.

Since 2008, baobab-fruit dried pulp is listed as an ingredient on the European Union's Novel Food Catalogue. By pulp production, 80% of the baobab fruit is discarded, forming side streams, namely, shell, fibrous filaments, and seeds. This study explored pulp and side-stream functional properties, including total dietary fiber (TDF), total antioxidant capacity (TAC), polyphenols, and water- (WHC) and oil-holding capacities (OHC), along with endocannabinoids (ECs) and N-acylethanolamines (NAEs) in pulp, seeds, and seed oil. Shell excelled in TDF (85%), followed by fibrous filaments (79%), and showed the highest soluble and direct TAC (72 ± 0.7 and 525 ± 1.0 µmol eq. Trolox/g, respectively). Pulp was the richest in polyphenols, followed by shell, fibrous filaments, and seeds. Quercetin predominated in shell (438.7 ± 2.5 µg/g); whereas epicatechin predominated in pulp (514 ± 5.7 µg/g), fibrous filaments (197.2 ± 0.1 µg/g), and seeds (120.1 ± 0.6 µg/g); followed by procyanidin B2 that accounted for 26-40% of total polyphenols in all the products. WHC and OHC ranged between 2-7 g H2O-Oil/g, with fibrous filaments showing the highest values. ECs were not found, whereas NAEs were abundant in seed oil (2408.7 ± 11.1 ng/g). Baobab shell and fibrous filaments are sources of polyphenols and antioxidant dietary fibers, which support their use as functional food ingredients.

Improvement of urinary tract symptoms and quality of life in benign prostate hyperplasia patients associated with consumption of a newly developed whole tomato-based food supplement: a phase II prospective, randomized double-blinded, placebo-controlled study.

BACKGROUND: Benign prostatic hyperplasia (BPH) is the most common urologic disease among elderly men. The diagnosis of BPH is usually driven by lower urinary tract symptoms (LUTS) that can significantly affect patients' quality of life. This phase II prospective, randomized double-blinded, placebo-controlled study aimed to determine the efficacy and safety of a novel whole tomato-based food supplement on LUTS of patients diagnosed with BPH. METHODS: Forty consecutive patients with histologically proved BPH were randomized 1:1 to receive daily for 2 months a sachet (5 g) of a newly developed whole tomato food supplement (WTFS) (treatment = Group A) or placebo (Group B). Patients were asked to fill the International Prostatic Symptom Score (IPSS) questionnaire before and after treatment. RESULTS: All but 1 patient in Group B successfully completed the scheduled regimen. No side effects were recorded. Unlike placebo, treatment significantly reduced (P < 0.0002) LUTS since mean IPSS decreased from 9.05 ± 1.15 to 7.15 ± 1.04 (paired t-test, two-tailed P-value < 0.001), and improved life quality (P < 0.0001). A trend toward a reduction of total PSA levels was observed in WTFS treated patients (8.98 ng/mL ± 1.52 vs 6.95 ± 0.76, P = 0.065), with changes being statistically significant only in the subgroup of patients with baseline levels above 10 ng/mL (18.5 ng/mL ± 2.7 vs 10.3 ± 2.1, P = 0.009). CONCLUSIONS: The new WTFS may represent a valid option for the treatment of symptomatic BPH patients. Unlike pharmacological treatments, the supplement is side effects free and highly accepted among patients.

Mediterranean diet consumption affects the endocannabinoid system in overweight and obese subjects: possible links with gut microbiome, insulin resistance and inflammation.

PURPOSE: To investigate whether a Mediterranean diet (MD) affected the plasma concentrations of endocannabinoids (ECs), N-acylethanolamines (NAEs) and their specific ratios in subjects with lifestyle risk factors for metabolic diseases. To identify the relationship between circulating levels of these compounds and gut microbiome, insulin resistance and systemic inflammation. METHODS: A parallel 8-week randomised controlled trial was performed involving 82 overweight and obese subjects aged (mean ± SEM) 43 ± 1.4 years with a BMI of 31.1 ± 0.5 kg/m2, habitual Western diet (CT) and sedentary lifestyle. Subjects were randomised to consume an MD tailored to their habitual energy and macronutrient intake (n = 43) or to maintain their habitual diet (n = 39). Endocannabinoids and endocannabinoid-like molecules, metabolic and inflammatory markers and gut microbiome were monitored over the study period. RESULTS: The MD intervention lowered plasma arachidonoylethanolamide (AEA, p = 0.02), increased plasma oleoylethanolamide/palmitoylethanolamide (OEA/PEA, p = 0.009) and OEA/AEA (p = 0.006) and increased faecal Akkermansia muciniphila (p = 0.026) independent of body weight changes. OEA/PEA positively correlated with abundance of key microbial players in diet-gut-health interplay and MD adherence. Following an MD, individuals with low-plasma OEA/PEA at baseline decreased homeostatic model assessment of insulin resistance index (p = 0.01), while individuals with high-plasma OEA/PEA decreased serum high-sensitive C-reactive protein (p = 0.02). CONCLUSIONS: We demonstrated that a switch from a CT to an isocaloric MD affects the endocannabinoid system and increases A. muciniphila abundance in the gut independently of body weight changes. Endocannabinoid tone and microbiome functionality at baseline drives an individualised response to an MD in ameliorating insulin sensitivity and inflammation. Clinical Trial Registry number and website NCT03071718; www.clinicaltrials.gov.

Endocannabinoids, endocannabinoid-like molecules and their precursors in human small intestinal lumen and plasma: does diet affect them?

PURPOSE: To determine the small intestinal concentration of endocannabinoids (ECs), N-acylethanolamines (NAEs) and their precursors N-acylphosphatidylethanolamines (NAPEs) in humans. To identify relationships between those concentrations and habitual diet composition as well as individual inflammatory status. METHODS: An observational study was performed involving 35 participants with an ileostomy (18W/17M, aged 18-70 years, BMI 17-40 kg/m2). Overnight fasting samples of ileal fluid and plasma were collected and ECs, NAEs and NAPEs concentrations were determined by LC-HRMS. Dietary data were estimated from self-reported 4-day food diaries. RESULTS: Regarding ECs, N-arachidonoylethanolamide (AEA) was not detected in ileal fluids while 2-arachidonoylglycerol (2-AG) was identified in samples from two participants with a maximum concentration of 129.3 µg/mL. In contrast, mean plasma concentration of AEA was 2.1 ± 0.06 ng/mL and 2-AG was 4.9 ± 1.05 ng/mL. NAEs concentrations were in the range 0.72-17.6 µg/mL in ileal fluids and 0.014-0.039 µg/mL in plasma. NAPEs concentrations were in the range 0.3-71.5 µg/mL in ileal fluids and 0.19-1.24 µg/mL in plasma being more abundant in participants with obesity than normal weight and overweight. Significant correlations between the concentrations of AEA, OEA and LEA in biological fluids with habitual energy or fat intakes were identified. Plasma PEA positively correlated with serum C-reactive protein. CONCLUSION: We quantified ECs, NAEs and NAPEs in the intestinal lumen. Fat and energy intake may influence plasma and intestinal concentrations of these compounds. The luminal concentrations reported would allow modulation of the homeostatic control of food intake via activation of GPR119 receptors located on the gastro-intestinal mucosa. CLINICAL TRIAL REGISTRY NUMBER AND WEBSITE: NCT04143139; www.clinicaltrials.gov .

An Oily Fish Diet Improves Subclinical Inflammation in People at High Cardiovascular Risk: A Randomized Controlled Study.

Interest has arisen on the anti-inflammatory action of dietary components, including long-chain n-3 fatty acids (LCn3) and polyphenols (PP). The aim of this study was to evaluate the effects of diets rich in PP and oily fish (high-LCn3 diets) on markers of subclinical inflammation and growth factors in people at high cardiometabolic risk. Individuals with high waist circumference and one more component of metabolic syndrome were randomized to one of the following isoenergetic diets: low LCn3&PP, high LCn3, high PP, high LCn3&PP. Before and after 8 weeks, fasting and postprandial plasma concentrations of hs-CRP and fasting serum concentrations of IL-1, IL-4, IL-6, IL-10, IL-17, INF-, TNF-, FGF, VEGF, PDGF-, G-CSF, and GM-CSF were determined. An oily fish diet reduced fasting plasma hs-CRP (1.28 ± 12.0, -12.5 ± 6.9, 22.5 ± 33.6, -12.2 ± 11.9; 8-week percent change, Mean ± SEM; low LCn3&PP, high LCn3, high PP, high LCn3&PP group, respectively), postprandial 6h-AUC hs-CRP (4.6 ± 16.3, -18.2 ± 7.2, 26.9 ± 35.1, -11.5 ± 11.8, 8-week percent change) and fasting IL-6 (20.8 ± 18.7, -2.44 ± 12.4, 28.1 ± 17.4, -9.6 ± 10.2), IL-17 (2.40 ± 4.9, -13.3 ± 4.9, 3.8 ± 4.43, -11.5 ± 4.7), and VEGF (-5.7 ± 5.8, -5.6 ± 7.5, 3.5 ± 5.8, -11.1 ± 5.5) (8-week percent change; p < 0.05 for LCn3 effect for all; no significant effect for PP; 2-factor ANOVA). An oily fish diet improved subclinical inflammation, while no significant effect was observed for dietary polyphenols.

Comparison of physical, microstructural and antioxidative properties of pumpkin cubes cooked by conventional, vacuum cooking and sous vide methods.

BACKGROUND: Current dietary guidelines recommend five or more fruit, vegetable, and legume servings per day. Often, these products are eaten cooked, resulting in organoleptic and nutritional changes. Vacuum cooking is gaining attention as an alternative cooking technique, due to its ability to preserve or even enhance sensory and healthy properties of food. Its household application is, however, poorly explored. In this work, the effect of vacuum cooking, performed with a new patented system, was studied for the first time on pumpkin cubes and compared to sous vide and traditional steam cooking, through a multidisciplinary approach. RESULTS: All the cooking treatments damaged pumpkin microstructure, leading to cell separation and plasmolysis; vacuum cooking was the most aggressive method, as confirmed by texture softening. Vacuum cooking was also the method with less impact on pumpkin color, in relation to the largest extraction of some classes of carotenoids from the broken cells. Significant polyphenol extraction, especially of gallic acid and naringenin, was instead observed for sous vide and steamed pumpkins. The total antioxidant activity, ascribable to the effect of both carotenoids and polyphenols, resulted enhanced after cooking compared to raw one mainly for cook vide samples, followed by steamed and sous vide ones. CONCLUSIONS: Vacuum cooking, followed by sous vide, has often shown better performance than traditional steam cooking for pumpkin cubes. The implementation of sous vide and vacuum cooking at domestic level or in professional kitchens, and in the food industry, would allow the consumption of vegetables with improved nutritional and sensorial characteristics. © 2020 Society of Chemical Industry.

Mediterranean diet intervention in overweight and obese subjects lowers plasma cholesterol and causes changes in the gut microbiome and metabolome independently of energy intake.

OBJECTIVES: This study aimed to explore the effects of an isocaloric Mediterranean diet (MD) intervention on metabolic health, gut microbiome and systemic metabolome in subjects with lifestyle risk factors for metabolic disease. DESIGN: Eighty-two healthy overweight and obese subjects with a habitually low intake of fruit and vegetables and a sedentary lifestyle participated in a parallel 8-week randomised controlled trial. Forty-three participants consumed an MD tailored to their habitual energy intakes (MedD), and 39 maintained their regular diets (ConD). Dietary adherence, metabolic parameters, gut microbiome and systemic metabolome were monitored over the study period. RESULTS: Increased MD adherence in the MedD group successfully reprogrammed subjects' intake of fibre and animal proteins. Compliance was confirmed by lowered levels of carnitine in plasma and urine. Significant reductions in plasma cholesterol (primary outcome) and faecal bile acids occurred in the MedD compared with the ConD group. Shotgun metagenomics showed gut microbiome changes that reflected individual MD adherence and increase in gene richness in participants who reduced systemic inflammation over the intervention. The MD intervention led to increased levels of the fibre-degrading Faecalibacterium prausnitzii and of genes for microbial carbohydrate degradation linked to butyrate metabolism. The dietary changes in the MedD group led to increased urinary urolithins, faecal bile acid degradation and insulin sensitivity that co-varied with specific microbial taxa. CONCLUSION: Switching subjects to an MD while maintaining their energy intake reduced their blood cholesterol and caused multiple changes in their microbiome and metabolome that are relevant in future strategies for the improvement of metabolic health.

A Mediterranean Diet Intervention Reduces the Levels of Salivary Periodontopathogenic Bacteria in Overweight and Obese Subjects.

The human oral cavity is a complex ecosystem, and the alterations in salivary microbial communities are associated with both oral and nonoral diseases. The Mediterranean diet (MD) is a healthy dietary pattern useful for both prevention and treatment of several diseases. To further explore the effects of the MD on human health, in this study, we investigated the changes in the salivary microbial communities in overweight/obese subjects after an individually tailored MD-based nutritional intervention. Healthy overweight and obese subjects were randomized between two intervention groups. The MD group (Med-D group) increased their MD adherence during 8 weeks of intervention while the control diet (control-D) group did not change their dietary habits. The salivary microbiota was assessed at baseline and after 4 and 8 weeks of intervention. Despite no observed changes in the overall salivary microbiota composition, we found a significant decrease in the relative abundances of species-level operational taxonomic units annotated as Porphyromonas gingivalis, Prevotella intermedia, and Treponema denticola in the Med-D group compared to that in the control-D group after 8 weeks of intervention, which are known to be associated with periodontal disease. Such variations were significantly linked to dietary variables such as MD adherence rates and intakes of animal versus vegetable proteins. In addition, increased levels of Streptococcus cristatus were observed in the Med-D group, which has been reported as an antagonistic taxon inhibiting P. gingivalis gene expression. Our findings suggest that an MD-based nutritional intervention may be implicated in reducing periodontal bacteria, and an MD may be a dietary strategy supportive of oral homeostasis.IMPORTANCE Changes in dietary behavior with increased adherence to a Mediterranean diet can determine a reduction of periodontopathogenic bacterial abundances in the saliva of overweight subjects with cardiometabolic risk due to an unhealthy lifestyle, without any change in individual energy intake, nutrient intake, and physical activity.

Twenty-five years of total antioxidant capacity measurement of foods and biological fluids: merits and limitations.

This review summarises 25 years of investigations on antioxidants research in foods and biological fluids and critically analyses the merits and limitations of using the total antioxidant capacity (TAC) measurement in the metabolomic era. An enormous bulk of knowledge was produced regarding the antioxidant capacity of foods and large TAC databases were developed. A direct link between a food TAC value and any health benefit is erroneous and has led to several cases of consumer deception. However, the striking epidemiological evidence associating a high dietary TAC with some disease prevention and the availability of well-constructed TAC databases deserve attention and must be taken into account to establish the usefulness of measuring TAC in both foods and biological samples. The in vivo TAC measurement, usually performed in plasma, is influenced by many external factors, such as dietary habits, as well as environmental and behavioural factors, which are integrated towards homeostatic control by fine physiological mechanisms with high inter-individual variability. Therefore, plasma TAC cannot be considered as a unique biomarker of individual antioxidant status. However, the combined evaluation of plasma TAC with known markers of disease, individual metabolism, inflammation and genetics, as well as with markers of gut microbiota composition and activity, may lead to the identification of populations that are more responsive to food/diet TAC. In this framework, the appropriate use of TAC measurement both in food and in vivo can still provide support for the interpretation of complex phenomena and be a tool for sample screening when making a quick decision toward in-depth research investigations. © 2018 Society of Chemical Industry.

Glucose- and Lipid-Related Biomarkers Are Affected in Healthy Obese or Hyperglycemic Adults Consuming a Whole-Grain Pasta Enriched in Prebiotics and Probiotics: A 12-Week Randomized Controlled Trial.

BACKGROUND: Synbiotic foods, which combine the action of prebiotics and probiotics along the gastrointestinal tract, can affect inflammatory and glucose-related markers. OBJECTIVE: The aim of this study was to investigate the effects on inflammatory and glycemia-related markers of a whole-grain pasta containing barley ß-glucans and Bacillus coagulans BC30, 6086 in healthy overweight or obese volunteers. METHODS: A single-blind, parallel, randomized, placebo-controlled dietary intervention study was carried out. Forty-one healthy sedentary overweight (body mass index [BMI] 25-29.9 kg/m2) and obese (BMI ≥30) volunteers, aged 30-65 y and low consumers of fruit and vegetables, ate 1 serving/d of whole-grain control (CTR) or innovative (INN) pasta for 12 wk and maintained their habitual diets. Biological samples were collected at baseline and every 4 wk for primary (plasma high-sensitivity C-reactive protein [hs-CRP] and fasting plasma lipid profile) and secondary outcomes (glycemia-related markers, blood pressure, fecal microbiota composition, and body weight). Between (CTR compared with INN) and within (among weeks) group differences were tested for the whole population and for subgroups stratified by baseline values of BMI (≥30) and glycemia (≥100 mg/dL). RESULTS: INN or CTR pasta consumption had no effect on primary and secondary outcomes over time, except for a significant increase in plasma γ-glutamyltransferase (GGT) after 12 wk of CTR pasta consumption. Comparisons between intervention groups revealed differences only at 12 wk: plasma GGT was higher in the CTR group; plasma hs-CRP, plasma LDL/HDL cholesterol ratio, and Bifidobacterium spp. were lower in the INN subgroup of obese volunteers; plasma resistin was lower and Faecalibacterium prausnitzii abundance was higher in the INN subgroup of hyperglycemic volunteers. CONCLUSIONS: A daily serving of a synbiotic whole-grain pasta had limited effects on primary and secondary outcomes in the entire group of volunteers but affected glycemia- and lipid-related markers and resistin in a subgroup of healthy obese or hyperglycemic volunteers. This trial was registered at clinicaltrials.gov as NCT02236533.

Different temperatures select distinctive acetic acid bacteria species and promotes organic acids production during Kombucha tea fermentation.

Kombucha is a traditional beverage produced by tea fermentation, carried out by a symbiotic consortium of bacteria and yeasts. Acetic Acid Bacteria (AAB) usually dominate the bacterial community of Kombucha, driving the fermentative process. The consumption of this beverage was often associated to beneficial effects for the health, due to its antioxidant and detoxifying properties. We characterized bacterial populations of Kombucha tea fermented at 20 or 30 °C by using culture-dependent and -independent methods and monitored the concentration of gluconic and glucuronic acids, as well as of total polyphenols. We found significant differences in the microbiota at the two temperatures. Moreover, different species of Gluconacetobacter were selected, leading to a differential abundance of gluconic and glucuronic acids.

Evaluation of microfiltration and heat treatment on the microbiological characteristics, phenolic composition and volatile compound profile of pomegranate (Punica granatum L.) juice.

BACKGROUND: Since processing technology and storage may influence the sensory and nutritional value as well as the shelf life of pomegranate juice (PJ), mild technologies based on microfiltration may be a promising alternative to heat treatments for fruit juice preservation. In this study, physicochemical and microbiological properties of raw (RPJ), microfiltered (MPJ) and cloudy pasteurized (PPJ) PJ were compared over a period of 4 weeks. RESULTS: Data demonstrated that microfiltration was comparable to pasteurization in guaranteeing microbiological stability of the juice, avoiding spoilage of the final product. After treatment, PPJ showed the highest amounts of gallic acid (GA) and ellagic acid derivatives (EAs). During storage, the amount of ellagitannins, EAs and GA similarly decreased in all types of juice. Trends towards variations of monomeric anthocyanins in MPJ and variations of polymeric and copigmented anthocyanins in both MPJ and PPJ were found over storage. CONCLUSION: The optimization of pretreatments and filtration parameters can lead to the industrial scale-up of microfiltration technology for the development of high-quality non-heat-treated PJ. © 2017 Society of Chemical Industry.

Microencapsulated bitter compounds (from Gentiana lutea) reduce daily energy intakes in humans.

Mounting evidence showed that bitter-tasting compounds modulate eating behaviour through bitter taste receptors in the gastrointestinal tract. This study aimed at evaluating the influence of microencapsulated bitter compounds on human appetite and energy intakes. A microencapsulated bitter ingredient (EBI) with a core of bitter Gentiana lutea root extract and a coating of ethylcellulose-stearate was developed and included in a vanilla microencapsulated bitter ingredient-enriched pudding (EBIP). The coating masked bitterness in the mouth, allowing the release of bitter secoiridoids in the gastrointestinal tract. A cross-over randomised study was performed: twenty healthy subjects consumed at breakfast EBIP (providing 100 mg of secoiridoids) or the control pudding (CP) on two different occasions. Blood samples, glycaemia and appetite ratings were collected at baseline and 30, 60, 120 and 180 min after breakfast. Gastrointestinal peptides, endocannabinoids (EC) and N-acylethanolamines (NAE) were measured in plasma samples. Energy intakes were measured at an ad libitum lunch 3 h after breakfast and over the rest of the day (post lunch) through food diaries. No significant difference in postprandial plasma responses of gastrointestinal hormones, glucose, EC and NAE and of appetite between EBIP and CP was found. However, a trend for a higher response of glucagon-like peptide-1 after EBIP than after CP was observed. EBIP determined a significant 30 % lower energy intake over the post-lunch period compared with CP. These findings were consistent with the tailored release of bitter-tasting compounds from EBIP along the gastrointestinal tract. This study demonstrated that microencapsulated bitter secoiridoids were effective in reducing daily energy intake in humans.

Food Liking Enhances the Plasma Response of 2-Arachidonoylglycerol and of Pancreatic Polypeptide upon Modified Sham Feeding in Humans.

BACKGROUND: Food palatability increases food intake and may lead to overeating. The mechanisms behind this observation are still largely unknown. OBJECTIVES: The aims of this study were the following: 1) to elucidate the plasma responses of endocannabinoids, N-acylethanolamines, and gastrointestinal peptides to a palatable (sweet), unpalatable (bitter), and sensory-acceptable (tasteless control) food, and 2) to verify whether some of these bioactive compounds can serve as plasma biomarkers of food liking in humans. METHODS: Three puddings providing 60 kcal (35% from proteins, 62% from carbohydrates, and 3% from fats) but with different taste were developed. Twenty healthy subjects (11 women and 9 men; mean age 28 y and BMI 22.7 kg/m(2)), selected because they liked the puddings in the order sweet > control > bitter, participated in a randomized crossover study based on a modified sham feeding (MSF) protocol. Blood samples at baseline and every 5 min up to 20 min after the MSF were analyzed for gastrointestinal peptides, endocannabinoids, and N-acylethanolamines. Thirty minutes after the MSF, energy intake at an ad libitum breakfast was measured. RESULTS: After the MSF, no response was observed in 7 of 9 gastrointestinal peptides measured. The plasma ghrelin concentration at 20 min after the sweet and bitter puddings was 25% lower than after the control pudding (P = 0.04), and the pancreatic polypeptide response after the sweet pudding was 23% greater than after the bitter pudding (P = 0.02). The plasma response of 2-arachidonoylglycerol after the sweet pudding was 37% and 15% higher than after the bitter (P < 0.001) and control (P = 0.03) puddings, respectively. Trends for greater responses of anandamide (P = 0.06), linoleoylethanolamide (P = 0.07), palmitoylethanolamide (P = 0.06), and oleoylethanolamide (P = 0.09) were found after the sweet pudding than after the bitter pudding. No differences in subsequent energy intake were recorded. CONCLUSIONS: The data demonstrated that food palatability influenced some plasma endocannabinoid and N-acylethanolamine concentrations during the cephalic phase response and indicated that 2-arachidonoylglycerol and pancreatic polypeptide can be used as biomarkers of food liking in humans.

Healthy virgin olive oil: a matter of bitterness.

Virgin olive oil (VOO) is the pillar fat of Mediterranean diet. It is made from olive fruits and obtained by squeezing olives without any solvent extraction. Respect to the seed oils, an unique polar polyphenol-rich fraction gives VOO a bitter and pungent taste. The recent substantiation by European Food Safety Authority (EFSA) of a health claim for VOO polyphenols may represent an efficient stimulus to get the maximum health benefit from one of the most valuable traditional product of Mediterranean countries educating consumers to the relationship between the VOO bitterness and its health effect. Agronomical practices and new processing technology to avoid phenolic oxidation and hydrolysis and to enhance the aromatic components of the VOO have been developed and they can be used to modulate taste and flavor to diversify the products on the market. VOOs having high concentration of phenol compounds are bitter and pungent therefore many people do not consume them, thus loosing the health benefits related to their intake. In this paper, the chemist's and nutritionist's point of view has been considered to address possible strategies to overcome the existing gap between the quality perceived by consumer and that established by expert tasters. Educational campaigns emphasizing the bitter-health link for olive oils should be developed.

Eicosapentaenoic acid free fatty acid prevents and suppresses colonic neoplasia in colitis-associated colorectal cancer acting on Notch signaling and gut microbiota.

Inflammatory bowel diseases are associated with increased risk of developing colitis-associated colorectal cancer (CAC). Epidemiological data show that the consumption of ω-3 polyunsaturated fatty acids (ω-3 PUFAs) decreases the risk of sporadic colorectal cancer (CRC). Importantly, recent data have shown that eicosapentaenoic acid-free fatty acid (EPA-FFA) reduces polyp formation and growth in models of familial adenomatous polyposis. However, the effects of dietary EPA-FFA are unknown in CAC. We tested the effectiveness of substituting EPA-FFA, for other dietary fats, in preventing inflammation and cancer in the AOM-DSS model of CAC. The AOM-DSS protocols were designed to evaluate the effect of EPA-FFA on both initiation and promotion of carcinogenesis. We found that EPA-FFA diet strongly decreased tumor multiplicity, incidence and maximum tumor size in the promotion and initiation arms. Moreover EPA-FFA, in particular in the initiation arm, led to reduced cell proliferation and nuclear ß-catenin expression, whilst it increased apoptosis. In both arms, EPA-FFA treatment led to increased membrane switch from ω-6 to ω-3 PUFAs and a concomitant reduction in PGE2 production. We observed no significant changes in intestinal inflammation between EPA-FFA treated arms and AOM-DSS controls. Importantly, we found that EPA-FFA treatment restored the loss of Notch signaling found in the AOM-DSS control and resulted in the enrichment of Lactobacillus species in the gut microbiota. Taken together, our data suggest that EPA-FFA is an excellent candidate for CRC chemoprevention in CAC.

Mediterranean diet and cardiovascular risk factors: a systematic review.

The aim of this paper was to systematically review and analyze the epidemiological evidence on the role of Mediterranean diet (MD) in the prevention of cardiovascular diseases (CVD). Fifty-eight studies exploring the relation between MD and lipoprotein concentration, antioxidative capacity and inflammatory markers, hypertension, obesity, diabetes, and metabolic syndrome, were identified and selected. These included 33 cross-sectional, 9 cohort, and 16 intervention studies. Most of the studies showed favorable effects of MD on CVD, although a certain degree of controversy remains in the respect of some issues, as obesity. Important methodological differences and limitations in the studies make difficult to compare results, thus further studies, particularly randomized clinical trials, are needed to finally substantiate the benefits of MD and to shed some lights on mechanisms.

Extra virgin olive oil: from composition to "molecular gastronomy".

The aim of this chapter is to provide a brief overview of the recent results of studies on extra virgin olive oil (EVOO) and its interactions with other food ingredients during cooking, to highlight basic molecular aspects of the "magic" of EVOO and its role in Mediterranean gastronomy. The use of raw EVOO added to foods after cooking (or as a salad oil) is the best way to express the original flavour and to maximize the intake of natural antioxidants and compounds related to positive effects on human health (hypotensive, anti-inflammatory, and anti-cancerogenic, among others). EVOO, however, also exhibits its protective properties during/after cooking. Different chemical interactions between biophenolic compounds and other food ingredients (water, milk proteins, carotenoids of tomato, omega-3 polyunsaturated fatty acids in canned-in-oil fish and meat or fish proteins) occur. Even during cooking, EVOO exhibits strong antioxidant properties and influences the overall flavour of cooked foods. The physical (partitioning, emulsion) and chemical (hydrolysis, covalent binding, antioxidant properties) phenomena occurring during cooking of EVOO are discussed with emphasis on the changes in the sensory (bitterness and fruity flavour) and nutritional qualities of some traditional Mediterranean foods. In particular, tomato-oil interactions during cooking, fish canning in EVOO, meat marinated in EVOO before cooking and roasting and frying in EVOO are examined. The interactions between EVOO antioxidants and flavours with milk proteins are also briefly discussed.

Food bioactive peptides: functionality beyond bitterness.

Bitter taste is an aversive taste because it is unconsciously associated with toxic compounds. However, a considerable variability in bitter sensitivity exists in those who have the genetic polymorphism for bitter taste receptors (TAS2Rs). Besides the oral cavity, TAS2Rs are present in many body tissues, including the gastrointestinal tract; therefore, they are crucial players both in the gustatory/hedonic system and in the homeostatic system, triggering numerous biological responses, including adipogenesis, carcinogenesis, or immunity. Bitter-tasting compounds are widely distributed in plant and animal foods and belong to many chemical classes. In this study, the evidence was reviewed on bitter peptides, considering the food sources, their formation in food under different processing and storage conditions and in the gastrointestinal tract during digestion, as well as their biological activities. Bitterness associated with peptides is due to the presence of hydrophobic amino acids in the C-terminus. The current literature mainly explores the enzymes and hydrolysis conditions, with the aim of reducing the formation of bitter peptides in hydrolysate preparation or food. Few studies highlight the bioactivity (namely, antihypertensive, antidiabetic, antioxidant, or immunity boosting), besides the bitterness. However, encapsulation of bitter peptides has been tentatively used to develop antihypertensive and antidiabetic supplements. In the era of personalized nutrition and precision medicine, the evidence available suggests the opportunity to use bitter bioactive peptides as functional ingredients in food. Such types of food may modulate a plethora of physiological mechanisms by targeting TAS2Rs in the gastrointestinal tract, thus modulating appetite sensations or gastrointestinal motility and discomfort according to individual nutritional needs and goals. More studies are needed to optimize the technological strategies to target TAS2Rs by bitter bioactive peptides, improve their stability in food, and validate the biological efficacy through well-designed in vivo studies.