Phenolic acids, lignans, and low-molecular-weight phenolics exhibit the highest in vitro cellular bioavailability in different digested and faecal-fermented phenolics-rich plant extracts.

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.

Oleuropein from olive leaf extracts and extra-virgin olive oil provides distinctive phenolic profiles and modulation of microbiota in the large intestine.

The interest in the modulation of gut microbiota by polyphenols from olives and derived products is increasing. In this work, phenolic leaf extracts (PLE) were in vitro faecal fermented to evaluate the changes in phenolic profiles and the impact on microbiota, using a commercial extra-virgin olive oil (EVOO) as reference. The in vitro fermentation decreased oleuropein content in PLE, determining an increase of hydroxytyrosol and other phenolic metabolites. An increase (p < 0.05) of hydroxytyrosol (LogFC = 6.02; VIP score = 1.05) was also observed in fermented EVOO. Besides, PLE significantly (p < 0.05) changed amino acids (LogFC = 6.1) and fatty acids (LogFC = 5.9) profile of the faeces. Metagenomic sequencing revealed that Coriobacteriaceae at the family level, and Collinsella at the genus level, were the most affected by PLE fermentation. These findings support the modulation of the gut microbiota exerted by phenolics from PLE and EVOO.

The functional potential of nine Allium species related to their untargeted phytochemical characterization, antioxidant capacity and enzyme inhibitory ability.

In this study, the aerial parts and bulbs of nine Allium species were investigated for their functional phytochemical profile, in vitro antioxidant activities, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), α-amylase, α-glucosidase, and tyrosinase inhibitory properties. Phenolics, alkaloids, glucosinolates and other sulfur-containing compounds were distinctively profiled in the different species. Maceration in methanol allowed recovering the highest cumulative phenolic content in A. scabrifolium (42.31 mg/g), followed by A. goekyigiti (33.15 mg/g) and A. atroviolaceum (28.35 mg/g). The aerial parts of all Allium species showed high in vitro antioxidant activity whereas methanolic extract of A. cappadocicum bulb showed the highest inhibition against AChE (2.44 mg galantamine equivalent/g) and the water extracts of A. isauricum aerial part were the best BChE inhibitors (4.31 mg galantamine equivalent/g). Bulbs were the richer source of oligosaccharides, and in vitro digestion determined an increase of oligosaccharides bioaccessibility. A promising nutraceutical potential could be highlighted in our understudied Allium species.

Comparative phytochemical profile of the elephant garlic (Allium ampeloprasum var. holmense) and the common garlic (Allium sativum) from the Val di Chiana area (Tuscany, Italy) before and after in vitro gastrointestinal digestion.

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.

Technological, nutritional, and sensory properties of durum wheat fresh pasta fortified with Moringa oleifera L. leaf powder.

BACKGROUND: Pasta is a staple food that is consumed worldwide and is an excellent product for the addition of ingredients rich in bioactive compounds. The fortification of pasta with such compounds could represent a healthy choice for consumers. RESULTS: In this study, fresh pasta was formulated by replacing durum wheat semolina with 0, 5, 10, and 15 g 100 g-1 of dried Moringa oleifera leaf powder (MOLP), rich in fibers, minerals, and antioxidant compounds. Increasing levels of MOLP influenced the technological and nutritional properties of wheat-based fresh pasta. Moringa oleifera reduced the optimum cooking time, the swelling index and firmness, while increasing the cooking loss and adhesiveness. From a nutritional viewpoint, the inclusion of MOLP enhanced the phenol content, the antioxidant activity, and the mineral content of fresh pasta. The products obtained had good sensorial acceptability and can make several nutritional claims due to MOLP richness minerals. CONCLUSIONS: The fortification of fresh pasta with MOLP could represent a valuable strategy to increase the nutritional value of the product, preserving pasta technological properties without affecting sensory acceptability. © 2020 Society of Chemical Industry.

Bioaccessibility of phenolic compounds following in vitro large intestine fermentation of nuts for human consumption.

A bioaccessibility study of polyphenols after in vitro simulated large intestine fermentation was carried out on edible nuts. Raw nuts were also analysed for total phenolic content and antioxidant potential, considering both bound and free phenolics. The highest phenolic content was found in walnuts, followed by pistachios extracts (596.9 and 410.1 mg gallic acid equivalents 100 g-1, respectively). Consistently, the total antioxidant capacity was highest in walnuts (3689.7 µM trolox equivalents 100 g-1) followed by peanuts and pistachios (3169.6 and 2990.1 µM trolox equivalents 100 g-1, respectively). Data showed high correlations between total phenolics and both antioxidant activities. The metabolomics-based phenolic profile depicted during in vitro fermentation showed a degradation of higher-molecular-weight phenolics over 48 hours of faecal fermentation, with a concurrent increase in low-molecular-weight compounds (hydroxybenzoic and hydroxycinnamic acids, alkylphenols, and tyrosols). Our findings indicate that nuts deliver polyphenols into the colon, with bioaccessibility values not negligible for alkylphenols, tyrosols and phenolic acids.

Impact of boiling on free and bound phenolic profile and antioxidant activity of commercial gluten-free pasta.

Cooking by boiling dry pasta could have varying degrees of influence on nutritional and functional components. In the present study, its effect on total phenolic content and antioxidant capacity, as well as on the comprehensive profile of free and bound phenolics, was investigated in six commercial gluten-free (GF) pasta products. Overall, the heat treatment caused a significant reduction (P<0.01) of the total phenolic content as well as FRAP reducing power and ORAC radical scavenging, with significant differences among the pasta samples considered. The highest values were recorded in free phenolic fraction remaining in black rice (41mggallic acid equivalents100g-1 and 25mmolTrolox Equivalents100g-1) and quinoa (24mggallic acid equivalents100g-1 and 14mmolTrolox Equivalents100g-1) cooked GF pasta. Significant correlations (P<0.01) could be found between total phenolics and both the antioxidant capacity assays performed. UHPLC-ESI/QTOF-MS mass profiling allowed confirming the spectrophotometric results, while identifying the amount of free and bound fractions. Among phenolic classes, lignans exhibited the highest decrease during the cooking process, followed by stilbenes and flavonoids. However, phenolic acids and other phenolics showed the highest stability. Furthermore, cooking by boiling strongly lowered the bound-to-free ratio of phenolic compounds, by an averaged factor ranging from 14-folds for flavonoids to 5-folds for other classes of phenolics.

Nutrition and Ageing.

The world elderly population is rapidly increasing. This demographic change represents a new challenge for the society and demands for a multisectorial intervention to promote a long, healthy, and active life span. Between the factors that contribute in fostering a long healthy life, the nutritional regime plays a central role and is recognized as a major factor in the onset of chronic diseases. A better understanding of the interaction between nutrition and ageing is essential to unravel the mechanisms responsible for these positive/negative effects and to identify diet components promoting the quality of life in the old age and to contribute to the prevention of late-life disabilities. At Università Cattolica del Sacro Cuore, the research activity in food science is focusing on four main objectives: food quality, food safety, functional foods and diet balancing. These objectives are the target of multidisciplinary ongoing and future research activities for a better understanding of the link between diet and ageing. Briefly, the different activities are addressed to the study of the following subjects: the most relevant factors affecting food choices and habits of old aged persons; the effects of long term low dose supplementation of conjugated linoleic acid in mouse; the use of low glycemic index and high resistant starch foods to prevent diabetes and obesity; the adjuvant effect of food bacteria for vaccination; the role of food ingredients in disease; the immunosuppression effect of mycotoxins, and its relevance in ageing people; the production of sustainable and natural antioxidant ingredients to encourage a healthy diet. Our research projects emphasize an holistic and integrated approach that, by bringing together complementary research groups, can combine the collective expertise and thus provide a comprehensive assessment of the role of nutrition in healthy ageing people.