Search

The fate of polyphenols from edible tree nuts was investigated using a simulated in vitro intestinal fermentation system. The digested food matrix was fermented for 48 h and the changes in the phenolic profiles were evaluated by both untargeted UHPLC-QTOF and targeted UHPLC-Orbitrap mass spectrometry. The untargeted metabolomics approach allowed us to monitor the comprehensive changes in phenolic profiles from 0 up to 48 h of in vitro fermentation. Multivariate statistics (i.e., orthogonal projection to latent structures discriminant analysis) applied to this untargeted data allowed us to identify the most discriminating phenolic metabolites and to further understand the colonic transformation pathways involved. In particular, 13 putatively identified compounds derived from flavonoids, lignans and phenolic acids were found to have the highest discrimination potential. Six phenolic metabolites were then quantified by means of targeted metabolomics (using a UHPLC-Orbitrap). These metabolites included 3,4-dihydroxyphenylacetic acid, 4-hydroxybenzoic acid, hippuric acid, caffeic acid, protocatechuic acid and protocatechuic aldehyde. Using the targeted data, a clear matrix effect was observed over time, with an increase of some phenolic metabolites moving from 8 to 48 h of in vitro fermentation. Based on these data, catabolic pathways for colonic microbial degradation of flavonoids, hydroxycinnamic acids, tyrosols and lignans are proposed. Our findings show that edible tree nuts deliver polyphenols to the colon, where several microbial transformations occur that lead to smaller phenolic metabolites being observed. Furthermore, we found that the combined use of targeted and untargeted metabolomics can be particularly effective for investigating the fate of polyphenols in the large intestine., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Interest in using polyphenols as modulators of the activity of starch digestive enzymes is increasing. The main purpose of this study was to investigate the role of phenolic compounds characterising pigmented maize flours in the modulation of in vitro starch digestibility. Flours from three different pigmented maize varieties were evaluated under cooking conditions and compared to common yellow maize (YM). The untargeted metabolomics-based approach comprehensively annotated around 300 phenolic compounds, with a high distribution of anthocyanins and phenolic acids (in free and bound fractions of maize samples) and significant differences across genotypes. Following in vitro starch digestion, the cooked pigmented maize flours showed higher resistant starch content (from 5.1 to 6.9 g /100 g dry matter), as well as lower starch hydrolysis index (HI) when compared to YM flour, with the "Rostrato Rosso" maize having the lowest HI (i.e., 61). Coherently, multivariate statistics following metabolomics showed the discrimination potential of anthocyanins' profile after cooking, characterising the "Rostrato Rosso" during in vitro digestion. These findings might be related to the modulation of enzyme activity by phenolic compounds during in vitro digestion. Therefore, the use of pigmented maize flours might help in the formulation of gluten-free foods with slowly digestible starches by exploiting the wide phenolic composition of these matrices., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The fate of phenolic compounds, along with short-chain fatty acids (SCFAs) production kinetics, was evaluated on six different commercial gluten-free (GF) pasta samples varying in ingredient compositions, focussing on the in vitro faecal fermentation after the gastrointestinal digestion. A general reduction of both total phenolics and reducing power was observed in all samples, together with a substantial change in phenolic profile over 24h of faecal fermentation, with differences among GF pasta samples. Flavonoids, hydroxycinnamics and lignans degraded over time, with a concurrent increase in low-molecular-weight phenolic acids (hydroxybenzoic acids), alkylphenols, hydroxybenzoketones and tyrosols. Interestingly, discriminant analysis also identified several alkyl derivatives of resorcinol as markers of the changes in phenolic profile during in vitro fermentation. Furthermore, degradation pathways of phenolics by intestinal microbiota have been proposed. Considering the total SCFAs and butyrate production during the in vitro fermentation, different fermentation kinetics were observed among GF pasta post-hydrolysis residues., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Mealworm, migratory locust, and house cricket have recently been recognized by the European Commission as novel foods, thus being suitable in different food applications. In this work, we tested their powders as meat extenders at 5% (w/w) inclusion in beef burgers, considering their ability to vehicle phenolic compounds during simulated in vitro static gastrointestinal digestion (INFOGEST). Insect powders were abundant in different phenolic classes, recording the highest values in locust (LP; 314.69 mg/kg), followed by cricket (CP; 113.3 mg/kg) and mealworm (MWP; 51.9 mg/kg). Following a pan-cooking process, LP burgers were confirmed as the best source of phenolics, with a marked abundance of flavonoids and phenolic acids. Interestingly, the insect powders were found to affect the in vitro gastrointestinal bioaccessibility of phenolic compounds when compared with the CTR burger, likely promoted by the interactions between the phenolic compounds and proteins characterizing the tested insect powders. Among the most discriminant phenolic metabolites at the gastrointestinal level, we found several phenolic acids (mainly hydroxycinnamics), recording the highest content for the digested CP-containing burgers. Finally, stilbenes showed significant correlation values at the intestinal level with both antioxidant and enzymatic activities, while total flavonoids were the most correlated with the inhibition of acetylcholinesterase. Taken together, our preliminary findings demonstrated that insect powders added to beef burgers can promote the bioaccessibility and potential bioavailability of phenolics in the distal tracts of the intestine. [ABSTRACT FROM AUTHOR]

This study evaluated the predicted glycemic index (pGI) in former food products (FFPs), and in two pig compound feeds formulated with or without the inclusion of FFPs. Six samples of FFPs and two pig compound feeds were used. FFPs were based on bakery and confectionary ex-food, while the pig compound feed was formulated by substituting 30% of cereals with FFPs (Feed FFP30%). All samples were analysed using an in vitro Englyst assay that simulates gastric and small intestinal digestion, and which has been proposed to determine the hydrolysis index (HI) and predict the glycemic index (pGI) of cereal-based foods introduced into pig diets. Corn meal, heat processed wheat and a conventional pig compound feed (Feed CTR) were included as control feed ingredients. In the assay, white bread was used as reference material. The results differentiated between two main groups of samples, namely: low HI samples with an HI lower than 100 including corn meal, Feed CTR, Feed FFP30%, flaked wheat and FFP4; and high HI samples including all the other FFPs tested. The same classification can be adopted for pGI. Thus combining HI and pGI results suggests that most of the FFPs tested in the present study were characterised by a high glycemic index potential which seems to be linked to the starch/sugars HI. The inclusion of FFPs in a commercial compound feed, and its effect on HI and pGI, merit further investigations. Ex-Food are food waste biomasses upgraded to feed ingredients; they are characterised by quick carbohydrates digestion and high glycemic index. [ABSTRACT FROM AUTHOR]

• High-amylose wheat flours (HAWF) exhibit a beneficial hypoglycaemic potential. • HAWF improved the microflora fermentative performance. • HAWFs showed a differential profile involving primary and specialized metabolites. • HAWF fermentates contain high levels of high-bioaccessibility bioactive compounds. • This approach opens new perspectives in the design of wheat-based functional foods. Wheat flour is one of the most prevalent foodstuffs for human consumption, and novel strategies are underway to enhance its nutritional properties. This work evaluated wholegrain flours from bread wheat lines with different amylose/amylopectin ratios through in vitro starch digestion and large intestine fermentation. High-amylose flours presented a higher resistant starch content and lower starch hydrolysis index. Moreover, UHPLC-HRMS metabolomics was carried out to determine the profile of the resulting in vitro fermentates. The multivariate analysis highlighted distinctive profiles between the flours derived from the different lines compared to the wild type. Peptides, glycerophospholipids, polyphenols, and terpenoids were identified as the main markers of the discrimination. The high-amylose flour fermentates showed the richest bioactive profile, containing stilbenes, carotenoids, and saponins. Present findings pave the way toward applying high-amylose flours to design novel functional foods. [ABSTRACT FROM AUTHOR]

One of the current tendencies in nutrition is to support the consumption of slowly digestible cereal-based foods with appreciable resistant starch (RS) content. Therefore, experimental cookies were formulated with normal amylose white wheat flour (NAWW) and increasing levels of high-amylose maize starch flour (HAMS) represented by substitution ratio of 0, 25 and 50% on a total flour (NAWW + HAMS) basis. Chemical composition, in vitro starch digestibility and sensory evaluation were investigated. Dietary fibre and total starch increased ( p < 0.05) when the level of HAMS increased in the recipe for cookies. Both RS and slowly digestible starch (SDS) increased ( p < 0.05), whereas rapidly digestible starch (RDS) fraction decreased ( p < 0.05) when the level of HAMS increased in the formulation. The rate of starch hydrolysis (k) and the predicted glycaemic index (pGI) decreased ( p < 0.05) when the HAMS increased in the composite, whereas no difference was reported in the sensory profile and in the overall acceptability of cookies. The higher levels of SDS and RS along with the lower RDS, pGI and k values indicated that the substitution of NAWW with HAMS contributed to formulate cookies with favourably SDS properties without affecting selected sensory characteristics. [ABSTRACT FROM AUTHOR]

Gluten free 'tagliatelle' were prepared with teff flour and increasing levels (0, 20 and 40%, w/w; indicating control, T20 and T40, respectively) of a new developed white-seeded low phytic acid and lectin free ( ws+lpa+lf) common bean flour. On a dry matter (DM) basis, total starch decreased ( p < 0.05) from 72.2 to 65.1 and 60.2%, while protein and dietary fibre increased ( p < 0.05) from 9.9 to 13.3% and 16.5% and from 8.5 to 11.8% and 15.7% for control, T20 and T40, respectively. The chemical score of protein increased ( p < 0.05) from 46 for control to 65 for T40. The colour was influenced ( p < 0.05) by bean inclusion, whereas no difference was reported for texture properties. The ws+lpa+lf bean inclusion increased ( p < 0.05) the resistant starch content (from 6.6% DM for control to 18.6% DM for T40) while decreased from 60 for control to 39 for T40 ( p < 0.05) the in vitro glycaemic index. The partial replacement of teff flour with bean flour can favourably be used in gluten free pasta formulation. [ABSTRACT FROM AUTHOR]

The use of rice/leguminous blend may be nutritionally convenient in gluten free product manufacturing. Gluten free spaghetti was prepared with rice flour and different concentrations of bean flour (included at levels of 0%, 20% and 40%, w/w) derived from a new developed white-seeded low phytic acid and lectin free ( ws + lpa + lf ) bean cultivar. Protein, ash and dietary fibre contents increased linearly ( P < 0.05) while total starch decreased quadratically ( P < 0.05) with the inclusion of ws + lpa + lf bean flour. The colour of spaghetti was influenced ( P < 0.05) by ws + lpa + lf bean inclusion. With respect to 0% spaghetti, the inclusion of ws + lpa + lf bean increased linearly ( P < 0.05) the optimal cooking time and the water absorption capacity, without affecting cooking loss and texture properties. The ws + lpa + lf bean inclusion increases quadratically ( P < 0.05) the resistant starch content, while decreasing quadratically ( P < 0.05) the in vitro glycemic index. The partial replacement of rice flour with bean flour can favourably be used in gluten free spaghetti formulation. [ABSTRACT FROM AUTHOR]

Dietary starch from feed grains represent the major energy-yielding sources in diets for large animals and starch effective digestion has a great impact on animal energy intake for meeting the substantial energy requirement to improve meat or milk productions. In general, site, extent and rate of starch digestion are affected by intrinsic and external factors that can be interrelated and are thus not easily defined. As a consequence, research to obtain a deeper knowledge on how starch chemical and structural compositions may affect starch digestion potential of feed grains and therefore their nutritional value has progressed recently. The objectives of this review are: (1) to give an overview on inherent starch primary structures and interactions with other compounds within feed grains; (2) to discuss factors affecting starch digestion potential in feed grains; (3) to explore starch digestion mechanism, and linkages with animal performances, both for swine and ruminants. The criticism of methods commonly used to estimate starch digestibility from feed grains for swine and ruminants are also discussed. [ABSTRACT FROM AUTHOR]

• Pigmented sorghum (PS) flours were abundant in flavonoids and phenolic acids. • Cooked PS flours had greater resistant starch (RS) content than white sorghum (WS) flour. • Polyphenols modulated the in vitro starch digestibility after cooking. • Anthocyanins and procyanidins discriminated PS vs WS flours during in vitro digestion. • Kafirins, flavonoids, RS and hydrolysis index values were strongly correlated. Polyphenols from five pigmented sorghum (PS) flours were in vitro evaluated as possible modulators of starch digestibility. White sorghum (WS) flour was used as control. Untargeted metabolomics depicted the phenolic composition of raw and cooked flours (obtained through heating at 100 °C for 30 min in water) highlighting differences in flavonoids and phenolic acids. Raw PS flours were characterized by greater tannin and kafirin contents when compared to WS, and, after cooking, PS flours had greater resistant starch (from 4.2 to 21.4 g /100 g dry matter), and lower starch hydrolysis index (HI) with respect to cooked WS. Multivariate statistics showed that flavonoids characterizing PS were the most discriminant compounds during the in vitro digestion. In addition, kafirin and total tannins content (on raw ingredients) along with the anthocyanin profiles (on cooked samples) were negative correlated with HI. Therefore, PS flours might be good candidates for the formulation of functional foods. [ABSTRACT FROM AUTHOR]

Artichoke is a relevant source of health-promoting compounds such as polyphenols and sesquiterpene lactones. In this study, the bioaccessibility and gut bioavailability of artichoke constituents were evaluated by combining in vitro digestion and large intestine fermentation, metabolomics, and Caco-2 human intestinal cells model. Moreover, the ability of artichoke polyphenols to modulate the in vitro starch digestibility was also explored. An untargeted metabolomic approach based on liquid chromatography quadrupole-time-of-flight (UHPLC/QTOF) mass spectrometry coupled with multivariate statistics was used to comprehensively screen the phytochemical composition of raw, digested, and fermented artichoke. Overall, a large abundance of phenolic acids and sesquiterpene lactones was detected, being 13.77 and 11.99 mg·g−1, respectively. After 20 h of in vitro large intestine fermentation, a decrease in polyphenols and sesquiterpene lactones content was observed. The most abundant compounds characterizing the raw material (i.e., chlorogenic acid and cynaropicrin equivalents) showed an average % bioaccessibility of 1.6%. The highest % bioaccessibility values were recorded for flavonoids such as anthocyanin and flavone equivalents (on average, 13.6%). However, the relatively high bioavailability values recorded for flavonols, phenolic acids, and sesquiterpene lactones (from 71.6% up to 82.4%) demonstrated that these compounds are able to be transported through the Caco-2 monolayer. The phenolic compounds having the highest permeation rates through the Caco-2 model included low molecular weight phenolics such as tyrosol and 4-ethylcatechol; the isoflavonoids 3′-O-methylviolanone, equol 4′-O-glucuronide, and hydroxyisoflavone; together with the methyl and acetyl derivatives of glycosylated anthocyanins. Therefore, although human in vivo confirmatory trials are deemed possible, current findings provide insights into the mechanistic effects underlying artichoke polyphenols and sesquiterpenoids bioavailability following gastrointestinal and large intestine processes. [ABSTRACT FROM AUTHOR]

In this work, different commercial extra-virgin olive oils (EVOO) were subjected to in vitro gastrointestinal digestion and the changes in bioactive compounds were evaluated by ultra-high-pressure liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry, using untargeted metabolomics. As expected, raw EVOO samples were abundant in total sterols (on average: 3007.4 mg equivalents/kg) and tyrosol equivalents (on average: 334.1 mg equivalents/kg). However, the UHPLC-QTOF screening allowed us to annotate 309 compounds, with a large abundance of sterols (219 compounds), followed by polyphenols (67 compounds) and terpenoids. The in vitro gastrointestinal digestion was found to affect the phytochemical composition of the different EVOO samples. In particular, both unsupervised and supervised statistics depicted the modifications of the bioactive profile following gastric and pancreatic phases. Overall, the compounds which resulted as the most affected by the in vitro digestion were flavonoids (cyanidin and luteolin equivalents), whilst relatively high % bioaccessibility values were recorded for tyrosol equivalents during the pancreatic phase (on average, 66%). In this regard, oleuropein-aglycone (i.e., the major phenolic compound in EVOO) was converted to hydroxytyrosol, moving from an average value of 1.3 (prior to the in vitro digestion) up to 9.7 mg equivalents/kg during the pancreatic step. As proposed in the literature, the increase in hydroxytyrosol might be the result of the combined effect of lipase(s) activity and acidic conditions. Taken together, the present findings corroborate the suitability of untargeted metabolomics coupled to in vitro digestion methods to investigate the bioaccessibility of phenolic compounds. In this regard, a significant impact of in vitro gastrointestinal digestion on polyphenolic profiles has been detected, thus suggesting the need to account for actual bioaccessibility values rather than just considering the amounts in the raw commodity. [ABSTRACT FROM AUTHOR]

• Yellow maize, quebracho and violet rice extracts were abundant in total phenolics. • Increased resistant starch fractions were associated with post-in vitro digestion. • Low bioaccessibility was observed for phenolic acids during in vitro digestion. • Matrix-related cellular bioavailability rates where observed. Polyphenols are multifaceted bioactive compounds, but little is known about their real impact on human health after consumption. In this work, the phenolic profiling of quebracho, yellow maize, and violet rice extracts was comprehensively investigated, together with the impact of in vitro digestion and colonic fermentation on the bioaccessibility and bioavailability of these phytochemicals. The different matrices showed distinct profiles, potentially influencing in vitro starch digestion under cooking conditions. Furthermore, after the extracts underwent in vitro gastrointestinal digestion and faecal fermentation, phenolics exhibited a differential bioaccessibility trend at every digestion level, with matrix-dependent behaviour. The bioavailability results suggest that polyphenols are metabolised during colonic fermentation, mainly into tyrosols, phenolic acids, and lignans, which are partially absorbed by Caco-2 cells. By combining metabolomics with in vitro cellular methods, this research provides new insights into the fate of these phytochemicals in the gut, yielding comprehensive data on their consumption in food matrices. [ABSTRACT FROM AUTHOR]

• Locust, cricket, and mealworm powders were abundant in bioactive compounds. • Following a 5% inclusion, mealworm-burgers showed the higher sensory acceptability. • Cricket powder (CP) reduced the accumulation of heterocyclic amines following cooking. • Dipeptides, such as glutaminylarginine, are biomarkers of in vitro digested CP-burgers. • A potential enzyme modulating activity was recorded for CP-burgers at intestinal level. Mealworm (MWP), migratory locust (LP), and house cricket (CP) are novel foods recently authorized by the European Commission. This work tested their powders as meat extenders at 5% inclusion in beef burgers. Insect powders were abundant in phenolics, recording the highest values in LP (1184.9 μg/g). The sensory analysis highlighted a higher visual and olfactory acceptability for MWP-burgers, followed by CP- and LP-burgers, whereas the texture of cooked burgers remained unaffected. Following pan-cooking, MWP-burgers and control exhibited comparable chemical profiles, while a significant down-accumulation of the heterocyclic amine 2-Amino-3,8-dimethylimidazo[4,5- f ]quinoxaline was observed in CP-burgers. In vitro gastrointestinal digestion highlighted metabolomic trends like control for MWP- and LP-burgers. In contrast, a reduced accumulation of lipids and increased content of dipeptides like glutaminylarginine (possibly acting as enzyme modulators) was observed for the CP-burgers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pectins and pectinase impact on polyphenols of cherry laurel puree was studied. • The fate of polyphenols along in vitro digestion and fermentation was modulated. • Pectins differentially protected polyphenols from digestion-derived degradation. • Pectinase improved polyphenols content facilitating their release from the fiber. • The pectic residues from pectinase digestion enhanced the human microbiota profile. Interactions between dietary fiber and phenolic compounds in foods can influence their gastrointestinal fate. This study aimed to examine the effect of four types of pectin on the polyphenols of cherry laurel puree and human gut microbiota during a simulated in vitro gastrointestinal digestion and large intestine fermentation. Results revealed that the combined addition of different pectins and pectinase to cherry laurel puree significantly affected the content and bioaccessibility of phenolics. The addition of pectins and pectinase distinctively impacted the phenolic subclasses in both raw and post-digested/fermented cherry laurel puree, suggesting differential interactions due to structural features. Both pectins and pectinase modulated the composition of fecal microbiota after in vitro fermentation, increasing bacterial diversity following pectinase treatment. The combined addition of pectins followed by pectinase had differential impacts on polyphenol bioaccessibility and gut microbiome diversity, hence having a potential outcome in terms of human health. [ABSTRACT FROM AUTHOR]

[Display omitted] • Five pigmented whole rice varieties were studied for their in vitro gastrointestinal digestive behavior. • The metabolomic profile was distinctively modulated following cooking and in vitro digestion in a variety-dependent manner. • Among flavonoids, anthocyanins were the most retained compounds following the cooking process. • Cooked Violet rice grains were characterized by the lowest starch hydrolysis index. • The in vitro digestion process was found to affect mainly flavonoids and phenolic acids. The untargeted metabolomic profile of five pigmented whole rice varieties, namely Ermes, Orange, Nerone, Venere, and Violet, was investigated. Samples were cooked to a comparable starch gelatinization level through an electric commercial rice cooker and in vitro digested to evaluate the fate of rice compounds during in vitro starch digestion. The untargeted metabolomics profiling depicted a broad phytochemical profile of rice grains, including phenolic compounds, terpenoids, and phytosterols, among others. Interestingly, the metabolomic profile showed distinctive shaping following cooking and in vitro digestion in a variety-dependent manner. Multivariate statistics revealed that glycosylated flavonoids and hydrolysis-products of tannins (such as 1,2-digalloyl-beta- D -glucopyranose) were the most discriminant compounds of the in vitro gastrointestinal digestion. The combination of cooking and simulated digestion was found to affect, in a matrix-driven manner, the profile of amino acids and lipids derivatives, together with sterols and terpenoids. Cooked Violet rice grains showed the lowest starch hydrolysis index (i.e. , 58.2) and the highest resistant starch content (i.e. , 4.8 g/100 g) compared to the other samples. Non-pigmented phenolic compounds could be included among discriminant compounds. After combining cooking and enzyme hydrolysis, Violet rice distinctively showed positive average LogFC values for flavonoids and phenolic acids. Overall, water-soluble anthocyanins were the most retained class of polyphenols following the cooking process, with peonidin 3-(6"-acetyl-glucoside) showing the highest discriminant potential (VIP score = 1.64). [ABSTRACT FROM AUTHOR]

• Elephant garlic (EG) has a 2-fold higher total phenolic content compared to common garlic (CG). • Some metabolites were the discriminant compounds in the raw bulbs. • Sulfur-containing compounds were found in lower amounts in EG. • Three aromatic compounds are the main biomarkers of EG consumption. This study is aimed to comparatively investigate the phytochemical profiles, focusing on the nutritional and phytochemical properties of common garlic (Allium sativum L.; CG) and elephant garlic (EG) (Allium ampeloprasum var. holmense) collected from the Val di Chiana area (Tuscany, Italy). The results showed a lower amount of fibers, demonstrating a higher digestibility of the bulb, and sulfur-containing compounds in EG rather than in CG. Untargeted metabolomic profiling followed by supervised and unsupervised statistics allowed understanding the differences in phytochemical composition among the two bulbs, both as raw bulbs, processed following the in vitro gastrointestinal digestion process. Typical sulfur-containing compounds, such as alliin and N -gamma-glutamyl-S-allyl cysteine, could notably be detected in lower amounts in EG. EG maintains a distinct phytochemical signature during in vitro gastrointestinal digestion. Our findings support the distinct sensorial attributes of the bulbs. [ABSTRACT FROM AUTHOR]