The human gastrointestinal tract is inhabited by a vast number of microorganisms that are called as the microbiota. Each individual harbors a unique gut microbial composition, this composition evolves throughout the host's lifetime and it is easily affected by internal or external changes. It has been shown that gut microbiota plays a crucial role in host's health and as this complex community has the ability to interact with each other and with the host's immune system, the presence or absence of some major species can affect the homeostasis. Diet can be considered as one of the pivotal factors in modulating the functionality, integrity, and composition of the gut microbiota as the gastrointestinal tract is the first organ exposed to components of the diet. In this review, we have focused on the effects of polyphenols, key compounds of a healthy diet with several biological activities, on the gut microbial composition, their biotransformation by the gut microbiota, and the effect of their reciprocal interactions in human health and disease.

Cucurbita genus has received a renowned interest in the last years. This plant species, native to the Americas, has served worldwide folk medicine for treating gastrointestinal diseases and intestinal parasites, among other clinical conditions. These pharmacological effects have been increasingly correlated with their nutritional and phytochemical composition. Among those chemical constituents, carotenoids, tocopherols, phenols, terpenoids, saponins, sterols, fatty acids, and functional carbohydrates and polysaccharides are those occurring in higher abundance. However, more recently, a huge interest in a class of triterpenoids, cucurbitacins, has been stated, given its renowned biological attributes. In this sense, the present review aims to provide a detailed overview to the folk medicinal uses of Cucurbita plants, and even an in-depth insight on the latest advances with regards to its antimicrobial, antioxidant and anticancer effects. A special emphasis was also given to its clinical effectiveness in humans, specifically in blood glucose levels control in diabetic patients and pharmacotherapeutic effects in low urinary tract diseases.

The Cucurbita genus, a member of Cucurbitaceae family, also known as cucurbits, is native to the Americas. Genus members, like Cucurbita pepo and Cucurbita maxima, have been used for centuries in folk medicine for treating gastrointestinal diseases and intestinal parasites. These pharmacological effects are mainly attributed to their phytochemical composition. Indeed, Cucurbita species are a natural source of carotenoids, tocopherols, phenols, terpenoids, saponins, sterols, fatty acids, functional carbohydrates, and polysaccharides, that beyond exerting remarkable biological effects, have also been increasingly exploited for biotechnological applications. In this article, we specifically cover the habitat, cultivation, phytochemical composition, and food preservative abilities of Cucurbita plants.

In this study, the aim was to evaluate the antimicrobial and antioxidant activities of thyme (Thymus vulgaris), oregano (Origanum vulgare), ginger (Zingiber officinale) and fennel (Foeniculum vulgare) essential oils in addition to their chemical compositions. Based on the results of gas chromatography‐mass spectrometry (GC—MS) analysis, major components were thymol andp‐cymene in thyme, carvacrol, andp‐cymene in oregano, α‐zingiberene and ar‐curcumene in ginger and (E)‐anethole in fennel essential oils. Essential oils were investigated for their antimicrobial activities by agar well diffusion and broth microdilution methods againstCampylobacter jejuniandCampylobacter coli. The inhibition zone diameters varied from 9.2 ± 0.7 to 28.7 ± 2.1 mm forC. jejuniand 14.7 ± 2.0 to 27.8 ± 2.8 mm forC. coli. While the minimum inhibitory concentrations (MICs) were lower for thyme and oregano EOs (5.65–43.20 μg/ml), the highest MIC value was obtained in fennel EO againstC. jejuni(28530 μg/ml). Total phenolic contents and antioxidant activities of these essential oils were evaluated by using Folin Ciocalteu, 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), Cupric Reducing Antioxidant Capacity (CUPRAC) and 2, 2‐azinobis(3‐ethylbenzo‐thiazoline)‐6‐sulphonic acid (ABTS) methods. The total phenolic content of the essential oils ranged between 7.72 (ginger) to 193 (thyme) mg GAE/L. Antioxidant activities of thyme and oregano were found to be the highest according to the ABTS method, whereas thyme was found to be the highest by the CUPRAC method and ginger by the DPPH method.

Anthocyanin-rich extract obtained from black chokeberry (Aronia melanocarpa) pomace was microencapsulated with spray drying by using different wall materials, i.e., maltodextrin with dextrose equivalent 6 (MD6), maltodextrin with dextrose equivalent 20 (MD20) and the combination of MD20 with gum Arabic (MD : GA, 15 : 5 w/w), whey protein isolate (MD : WPI, 19 : 1 w/w), and xanthan gum (MD : XG, 19.5 : 0.5 w/w). Spray drying conditions were chosen as follows: inlet temperature of 150 °C, outlet temperature of 90 °C, 4.5 mL min⁻¹ feed flow rate, 0.357 m³ h⁻¹ air flow rate, and an aspirator capacity of 100%. Physicochemical characteristics of the powders such as moisture content, particle size, capsule morphology, color, spray drying yield, encapsulation efficiency, total anthocyanin content, total and individual phenolic content, and total antioxidant activity were investigated. With all the parameters evaluated, MD : GA wall material provided better results particularly in terms of production yield and encapsulation efficiency. To conclude, black chokeberry by-product can be used as a source of polyphenols to produce value-added colored powders with bioactive properties which might have the potential to be used in food, nutraceutical and cosmetic industries.

Diabetes mellitus involves high blood sugar levels due to insufficient insulin action. Furthermore, enzymes such as α‐amylase and α‐glucosidase break down carbohydrates into glucose, leading to postprandial hyperglycemia. Flavonoids, particularly quercetin, inhibit these enzymes, slowing carbohydrate digestion and reducing glucose absorption. Quercetin has significant hypoglycemic effects with inhibitory concentration (IC₅₀) values comparable to acarbose, a standard inhibitor, suggesting its potential as a natural alternative for diabetes management. In silico models, including molecular docking, molecular dynamics (MD) simulations, and quantitative structure‐activity relationship (QSAR) approaches, help researchers understand the molecular interactions of therapeutic agents. These techniques identify potential inhibitors, determine enzyme‐inhibitor structures, and calculate binding energies, correlating findings with in vitro or in vivo data. Molecular docking predicts molecular orientations, MD simulations offer insights into enzyme–inhibitor dynamics, and QSAR models predict inhibitory potential based on structural properties. Studies have shown that quercetin effectively inhibits α‐glucosidase and α‐amylase by forming hydrogen bonds with specific amino acid residues. Quercetin interacts with starches and reduces their digestibility, increases the formation of resistant starch, lowers the glycemic index, and inhibits digestive enzymes. Studies show that the effects of quercetin on starch digestion vary with concentration and type of starch, and its incorporation into foods such as bakery products, pasta, etc. can significantly decrease starch hydrolysis. The incorporation of quercetin into starch matrices may aid in the development of functional foods aimed at improving glycemic control.