Inhibition of α-amylase, α-glucosidase and pancreatic lipase by phenolic compounds of Rumex maderensis (Madeira sorrel). Influence of simulated gastrointestinal digestion on hyperglycaemia-related damage linked with aldose reductase activity and protein glycation

Effect of Protein, Carbohydrate, and Oil on Phytochemical Bioaccessibility and Bioactivities of the Ginkgo biloba L. Leaf Formulations After In Vitro Digestion

The present work evaluates the effect of casein, glucose, and olive oil on phytochemical bioaccessibility, antioxidant potential (DPPH and FRAP), antidiabetic potential (inhibition of amylase, α-glucosidase, and BSA glycation), and antihyperlipidemic potential (inhibition of lipase) of gingko standardized leaf extract in the form of tablets after in vitro digestion. Gingko extract formulations with protein, carbohydrates, and oil had high (>70%) in vitro bioaccessibility of quercetin, kaempferol, and isorhamnetin after each phases of digestion in comparison to moderate (35-70%) in vitro bioaccessibility from gingko water extract. Formulation with the highest in vitro bioaccessibility of the majority of the tested polyphenolic groups and terpene lactones after oral and intestinal phases was ginkgo with olive oil. High (>70%) antioxidant (DPPH and FRAP), antidiabetic (α-glucosidase and BSA glycation), and antihyperlipidemic potential were detected in almost all ginkgo formulations. Based on the results, we conclude that the in vitro bioaccessibility of individual compounds or groups of compounds depends on whether the tablets are taken with water or with foods (protein, carbohydrates, and oil).

Effect of Extraction Methods on Chemical Characteristics and Bioactivity of Chrysanthemum morifolium cv. Fubaiju Extracts

Chrysanthemum morifolium cv. Fubaiju (CMF) is regarded as one of the three most renowned varieties of white Chrysanthemum in China, and different extraction methods have significant effects on its composition and activities. Therefore, six extractions were used in this study to assess the effects on extracts. The basic chemical composition showed that hot water extract (Hw) had the highest total phenolic content, alkali water immersion-assisted hot water extract (Al) had the highest content of protein, and enzyme-assisted hot water extract (Enz) had the highest content of carbohydrate. The UPLC-Q-Exactive-MS results evinced the presence of 19 small-molecule compounds, including chlorogenic acid, caffeic acid, tuberonic acid glucoside, luteolin-7-O-rutinoside, and other substances. In addition, the antioxidant test found that the Hw exhibited the best 1,1-diphenyl-2-picrylhydrazyl (DPPH) (82.05 ± 1.59 mM TE/mg) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) (61.91 ± 0.27 mM TE/mg) scavenging ability. The anti-glycation test demonstrated that Enz possessed the most pronounced inhibitory effect on glycation products, including fructosamine and advanced glycation end products (AGEs). Additionally, the Enz also exhibited the most significant inhibitory effect on the protein oxidation product N'-formylkynurenine. The correlation analysis revealed that there was a close relationship between antioxidant properties and glycation resistance of extracts, and tuberonic acid glucoside, 1,3-di-O-caffeoylquinic acid, 1,4-Dicaffeoylquinic acid, quercetin-7-O-β-D-glucopyranoside, and isochlorogenic acid B were key small molecule components that affected activities. In summary, the extracts of CMF can be regarded as an excellent antioxidant and anti-glycosylation agent.

Changes in Phenolic Composition and Bioactivities of Ayocote Beans under Boiling (Phaseolus coccineus L.)

Ayocote beans (Phaseolus coccineus L.) are a rich source of some bioactive molecules, such as phenolic compounds that exhibit antioxidant capacity that promote health benefits. Ayocote is mainly consumed after cooking, which can impact the antioxidant characteristics of the phenolic compounds responsible for some of its health benefits. Therefore, this study investigated the effects of boiling on the phenolic composition and bioactivities of ayocote beans before and after boiling. Boiling decreased the total phenolic content (70.2, 60.3, and 58.2%), total anthocyanin (74.3, 80.6, and 85.7%), and antioxidant activity (DPPH: 41.2, 46.9, and 59.1%; ORAC: 48.23, 53.6 and 65.7%) of brown, black, and purple ayocote beans, respectively. All the extracts also inhibited the activity of α-glucosidase with efficacy values from 29.7 to 87.6% and α-amylase from 25.31 to 56.2%, with moderate antiglycation potential (15.2 to 73.2%). Phenolic acids, anthocyanins, and flavonoid decreases were detected in boiled samples by HPLC-MS analysis. Although boiling reduced the phenolic compounds, bioactive compounds remained in a considerable content in boiled ayocote.

Polysaccharides from Seedless Chestnut Rose (Rosa sterilis) Fruits: Insights into Innovative Drying Technologies and Their Structural Characteristics, Antioxidant, Antiglycation, and α-Glucosidase Inhibitory Activities

The selection of an optimal drying method is essential for extending the shelf life and enhancing the quality of Rosa sterilis fruits. This study investigated the effects of both innovative (microwave vacuum drying and infrared drying) and traditional (freeze-drying and hot air drying) techniques on the structural characteristics and bioactivities of polysaccharides from R. sterilis fruits (RSPs). Four different RSPs were obtained from fruits dried using these methods. Results demonstrated that the structural characteristics and bioactivities of RSPs varied significantly with the drying method. Notable differences were observed in extraction yield, total sugar, uronic acid content, monosaccharide molar ratios, molecular weight distribution, particle size, thermal stability, and microstructures of RSPs. Despite these variations, the types of constituent monosaccharides and major glycosidic linkages remained consistent across all methods. Notably, RSPs obtained via microwave vacuum drying (RSPs-MVD) showed a higher uronic acid content and lower molecular weight, and exhibited stronger in vitro antioxidant, α-glucosidase inhibitory, and antiglycation activities. These findings suggest that microwave vacuum drying is an effective pre-drying technique for extracting RSPs, making them suitable as bioactive ingredients in functional foods and pharmaceuticals for managing diabetes mellitus and its complications.

Development and evaluation of anti-reflux functional-oral suspension raft composed of sodium alginate-mung bean protein complex

This study aimed to develop a sodium alginate (Na alginate) and mung bean protein (MBP) raft complex to improve gastric reflux symptoms. Na alginate and MBP complexes with different ratios (1:1, 2:1, and 3:1, respectively) were used for raft formulations through a wet Maillard reaction. Structural properties of raft strength, reflux resistance, intrinsic fluorescence emission spectroscopy, and Fourier transform infrared spectroscopy (FTIR) were investigated for rafts. The suspension 1:1 Na alginate/MBP with 0 h Maillard reaction time exhibited the lowest sedimentation volume among the suspensions. In contrast, 3:1 Na alginate/MBP with 6 h Maillard reaction time showed the highest sedimentation volume. Based on the results, the 3:1 Na alginate/MBP rafts had the best results, and the results were within acceptable limits. Functional properties, including antioxidant properties, the Helicobacter pylori inhibition assay, the pancreatic lipase inhibition assay, and angiotensin-converting enzyme (ACE) inhibition, were investigated for rafts. The Na alginate/MBP raft has similar characteristics to Gaviscon syrup and can be used for obesity, Helicobacter pylori infection, high blood pressure, and gastric reflux.

Enhancing activity of food protein-derived peptides: An overview of pretreatment, preparation, and modification methods

Food protein-derived peptides have garnered considerable attention due to their potential bioactivities and functional properties. However, the limited activity poses a challenge in effective utilization aspects. To overcome this hurdle, various methods have been explored to enhance the activity of these peptides. This comprehensive review offers an extensive overview of pretreatment, preparation methods, and modification strategies employed to augment the activity of food protein-derived peptides. Additionally, it encompasses a discussion on the current status and future prospects of bioactive peptide applications. The review also addresses the standardization of mass production processes and safety considerations for bioactive peptides while examining the future challenges and opportunities associated with these compounds. This comprehensive review serves as a valuable guide for researchers in the food industry, offering insights and recommendations to optimize the production process of bioactive peptides.

Evaluation of α-Glucosidase Inhibition and Antihyperglycemic Activity of Extracts Obtained from Leaves and Flowers of Rumex crispus L

Among antihyperglycemic drugs used for treating diabetes, α-glucosidase inhibitors generate the least adverse effects. This contribution aimed to evaluate the potential antidiabetic activity of Rumex crispus L. by testing its in vitro α-glucosidase inhibition and in vivo antihyperglycemic effects on rats with streptozotocin (STZ)-induced diabetes. Better inhibition of α-glucosidase was found with the methanol extract versus the n-hexane and dichloromethane extracts. The methanol extract of the flowers (RCFM) was more effective than that of the leaves (RCHM), with an IC50 of 7.3 ± 0.17 μg/mL for RCFM and 112.0 ± 1.23 μg/mL for RCHM. A bioactive fraction (F89s) also showed good α-glucosidase inhibition (IC50 = 3.8 ± 0.11 μg/mL). In a preliminary study, RCHM and RCFM at 150 mg/kg and F89s at 75 mg/kg after 30 days showed a significant effect on hyperglycemia, reducing glucose levels (82.2, 80.1, and 84.1%, respectively), and improved the lipid, renal, and hepatic profiles of the rats, comparable with the effects of metformin and acarbose. According to the results, the activity of R. crispus L. may be mediated by a diminished rate of disaccharide hydrolysis, associated with the inhibition of α-glucosidase. Thus, R. crispus L. holds promise for the development of auxiliary drugs to treat diabetes mellitus.

Valorization of different low-grade date (Phoenix dactylifera L.) fruit varieties: A study on the bioactive properties of polyphenolic extracts and their stability upon in vitro simulated gastrointestinal digestion

Nowadays, the development of suitable strategies for the management and valorization of agri-food products is one of the most important challenges worldwide. In this context, the current research study aimed to explore a valorization strategy for different varieties (Khalas, Jabri, Lulu, Booman, and Sayer) of low-grade date fruit by extracting polyphenolic compounds and investigating their health-promoting bioactive properties. The generated extracts were comparatively analyzed for their phenolic contents, antioxidant, anti-inflammatory, anti-hemolytic, and enzyme inhibitory activities upon in vitro simulated gastrointestinal digestion (SGID). The total phenolic contents (TPC) ranged from 217.3 to 1846.9 mg GAE/100 g fresh weight. After complete SGID, the TPC remarkably increased from 570.8 mg GAE/100 g fresh weight (undigested), reaching the highest value of 1606.3 mg GAE/100 g fresh weight with the Khalas cultivar. Overall, gastric and complete-SGID-treated extracts exhibited higher antioxidant activities, compared to the undigested extracts for the five selected date varieties. Similarly, the gastric and complete SGID promoted the release of bioactive components endowed with significantly higher inhibition levels towards digestive enzymes related to diabetes. Moreover, extracts from all varieties revealed an increase in the inhibition of lipidemic-related enzymatic markers and anti-inflammatory activities when subjected to the gastric digestion phase, which decreased after complete SGID. Principal component analysis (PCA) suggested that higher bioactive properties were influenced by the TPC present in the samples. Overall, low-quality dates could be considered as a potential source of bioactive polyphenols with interesting nutraceutical properties, released upon their transit through the gastrointestinal tract.

Food Polyphenols and Type II Diabetes Mellitus: Pharmacology and Mechanisms

Type II diabetes mellitus and its related complications are growing public health problems. Many natural products present in our diet, including polyphenols, can be used in treating and managing type II diabetes mellitus and different diseases, owing to their numerous biological properties. Anthocyanins, flavonols, stilbenes, curcuminoids, hesperidin, hesperetin, naringenin, and phenolic acids are common polyphenols found in blueberries, chokeberries, sea-buckthorn, mulberries, turmeric, citrus fruits, and cereals. These compounds exhibit antidiabetic effects through different pathways. Accordingly, this review presents an overview of the most recent developments in using food polyphenols for managing and treating type II diabetes mellitus, along with various mechanisms. In addition, the present work summarizes the literature about the anti-diabetic effect of food polyphenols and evaluates their potential as complementary or alternative medicines to treat type II diabetes mellitus. Results obtained from this survey show that anthocyanins, flavonols, stilbenes, curcuminoids, and phenolic acids can manage diabetes mellitus by protecting pancreatic β-cells against glucose toxicity, promoting β-cell proliferation, reducing β-cell apoptosis, and inhibiting α-glucosidases or α-amylase. In addition, these phenolic compounds exhibit antioxidant anti-inflammatory activities, modulate carbohydrate and lipid metabolism, optimize oxidative stress, reduce insulin resistance, and stimulate the pancreas to secrete insulin. They also activate insulin signaling and inhibit digestive enzymes, regulate intestinal microbiota, improve adipose tissue metabolism, inhibit glucose absorption, and inhibit the formation of advanced glycation end products. However, insufficient data are available on the effective mechanisms necessary to manage diabetes.

Effect of Hot- and Cold-Water Treatment on Broccoli Bioactive Compounds, Oxidative Stress Parameters and Biological Effects of Their Extracts

The goal of this work was to define resistant and susceptible variables of young broccoli (Brassica oleracea L. convar. botrytis (L.) Alef. var. cymosa Duch.) plants treated with cold and hot water. Additionally, we wanted to single out variables that could potentially be used as biomarkers of cold/hot-water stress in broccoli. Hot water changed more variables (72%) of young broccoli than cold water (24%) treatment. Hot water increased the concentration of vitamin C for 33%, hydrogen peroxide for 10%, malondialdehyde for 28%, and proline for 147%. Extracts of broccoli stressed with hot water were significantly more efficient in the inhibition of α-glucosidase (65.85 ± 4.85% compared to 52.00 ± 5.16% of control plants), while those of cold-water-stressed broccoli were more efficient in the inhibition of α-amylase (19.85 ± 2.70% compared to 13.26 ± 2.36% of control plants). Total glucosinolates and soluble sugars were affected by hot and cold water in an opposite way, which is why they could be used as biomarkers of hot/cold-water stress in broccoli. The possibility of using temperature stress to grow broccoli enriched with compounds of interest to human health should be further investigated.

Dietary Supplementation of Caulerpa racemosa Ameliorates Cardiometabolic Syndrome via Regulation of PRMT-1/DDAH/ADMA Pathway and Gut Microbiome in Mice

This study evaluated the effects of an aqueous extract of Caulerpa racemosa (AEC) on cardiometabolic syndrome markers, and the modulation of the gut microbiome in mice administered a cholesterol- and fat-enriched diet (CFED). Four groups of mice received different treatments: normal diet, CFED, and CFED added with AEC extract at 65 and 130 mg/kg body weight (BW). The effective concentration (EC₅₀) values of AEC for 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and lipase inhibition were lower than those of the controls in vitro. In the mice model, the administration of high-dose AEC showed improved lipid and blood glucose profiles and a reduction in endothelial dysfunction markers (PRMT-1 and ADMA). Furthermore, a correlation between specific gut microbiomes and biomarkers associated with cardiometabolic diseases was also observed. In vitro studies highlighted the antioxidant properties of AEC, while in vivo data demonstrated that AEC plays a role in the management of cardiometabolic syndrome via regulation of oxidative stress, inflammation, endothelial function (PRMT-1/DDAH/ADMA pathway), and gut microbiota.

Anti-obesity, anti-hyperglycaemic, anti-antipyretic and analgesic activities of Globularia alypum extracts

OBJECTIVES

The aim of this study is to evaluate the anti-obesity, anti-hyperglycaemic, analgesic and antipyretic activities of Globularia alypum (GA).

MATERIALS AND METHODS

GA methanol and water extracts (GAME, GAWE) were administered to high-fat-high-glucose diet (HFFD) rats.

RESULTS

This study showed that GAME exhibited the highest antioxidant, anti-α-amylase and anti-lipase activities, with half inhibitory concentration (IC50) values 0.067, 1.05 and 2.97 mg/ml respectively. In HFFD rats, the administration of GAME inhibited lipase activity by 36, 37 and 30% in the intestine, pancreas and serum, respectively, reduced body weight by 17.7% and modulated lipid profile. In addition, administration of GAME to HFFD-rats decreased α-amylase activity, improved glucose level and protected liver function. Furthermore, the administration of GA extracts to rats revealed antipyretic (reduction in writhing by 64%) and analgesic (decrease of temperature by 1.11 °C) activities.

CONCLUSION

This study showed that GA extracts exhibited an anti-obesity, anti-hyperglycaemia, anti-pyretic and analgesic activities.

The flavonoid profiles in the pulp of different pomelo (Citrus grandis L. Osbeck) and grapefruit (Citrus paradisi Mcfad) cultivars and their in vitro bioactivity

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Fourteen flavonoid compounds were detected in pomelo and grapefruit pulp.

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The flavonoid profiles in pomelo and grapefruit pulp had varietal difference.

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Flavonoids of pomelo and grapefruit showed strong cellular antioxidant activity.

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Flavonoids of pomelo and grapefruit are good inhibitors of pancreatic lipase.

Previous results indicated that the flavonoid profiles might have varietal differences in pomelo, but detailed information is unknown. We previously isolated 4 new flavonoids, cigranoside C, D, E, F, in Citrus grandis Shatianyu pulp. However, their distribution in different pomelo cultivars remains to be explored. Therefore, the flavonoid profiles and in vitro bioactivity of the pulp from 5 pomelo and 1 grapefruit cultivars commonly consumed in China were investigated. Fourteen flavonoids were identified, cigranoside C, D, E were detected in these pomelo and grapefruit. Naringin and cigranoside C were the major flavonoids in grapefruit, Guanximiyu-W, Guanximiyu-R and Liangpingyu, while melitidin and rhoifolin was the predominant flavonoid in Shatianyu and Yuhuanyu, respectively. Pomelo and grapefruit showed strong antioxidant activity, and were potent inhibitors of pancreatic lipase with IC₅₀ values of 11.4–72.6 mg fruit/mL except Shatianyu. Thus, pomelo and grapefruit are natural antioxidants and possess anti-obesity potential.

Therapeutic Potential of Quercetin in the Management of Type-2 Diabetes Mellitus

Diabetes Mellitus (DM) is a metabolic disorder that is spreading alarmingly around the globe. Type-2 DM (T2DM) is characterized by low-grade inflammation and insulin resistance and is closely linked to obesity. T2DM is mainly controlled by lifestyle/dietary changes and oral antidiabetic drugs but requires insulin in severe cases. Many of the drugs that are currently used to treat DM are costly and present adverse side effects. Several cellular, animal, and clinical studies have provided compelling evidence that flavonoids have therapeutic potential in the management of diabetes and its complications. Quercetin is a flavonoid, present in various natural sources, which has demonstrated in vitro and in vivo antidiabetic properties. It improves oral glucose tolerance, as well as pancreatic β-cell function to secrete insulin. It inhibits the α-glucosidase and DPP-IV enzymes, which prolong the half-life of glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP). Quercetin also suppresses the release of pro-inflammatory markers such as IL-1β, IL-4, IL-6, and TNF-α. Further studies are warranted to elucidate the mode(s) of action of quercetin at the molecular level. This review demonstrates the therapeutic potential of quercetin in the management of T2DM.

The genus Rumex (Polygonaceae): an ethnobotanical, phytochemical and pharmacological review

Rumex L., a genus in Polygonaceae family with about 200 species, is growing widely around the world. Some Rumex species, called "sorrel" or "dock", have been used as food application and treatment of skin diseases and hemostasis after trauma by the local people of its growing areas for centuries. To date, 29 Rumex species have been studied to contain about 268 substances, including anthraquinones, flavonoids, naphthalenes, stilbenes, diterpene alkaloids, terpenes, lignans, and tannins. Crude extract of Rumex spp. and the pure isolates displayed various bioactivities, such as antibacterial, anti-inflammatory, antitumor, antioxidant, cardiovascular protection and antiaging activities. Rumex species have important potential to become a clinical medicinal source in future. This review covers research articles from 1900 to 2022, fetched from SciFinder, Web of Science, ResearchGate, CNKI and Google Scholar, using "Rumex" as a search term ("all fields") with no specific time frame set for the search. Thirty-five Rumex species were selected and summarized on their geographical distribution, edible parts, traditional uses, chemical research and pharmacological properties.

Stability, Morphology, and Effects of In Vitro Digestion on the Antioxidant Properties of Polyphenol Inclusion Complexes with β-Cyclodextrin

Polyphenols are inversely associated with the incidence of chronic diseases, but therapeutic use is limited by poor stability and bioaccessibility. Encapsulation has been shown to overcome some of these limitations. A selection of polyphenols (catechin, gallic acid, and epigallocatechin gallate) and their combinations were encapsulated in beta-cyclodextrin (βCD). Encapsulation was characterized and the thermal and storage stability was evaluated using the 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay. The samples were then subjected to in vitro digestion using a simple digestion (SD) model (gastric and duodenal phases) and a more complex digestion (CD) model (oral, gastric, and duodenal phases). Thereafter, the chemical (oxygen radical absorbance capacity assay) and cellular (dichlorofluorescein diacetate assay in Caco-2 cells) antioxidant and antiglycation (advanced glycation end-products assay) activities were determined. Inclusion complexes formed at a 1:1 molar ratio with a high encapsulation yield and efficiency. Encapsulation altered the morphology of the samples, increased the thermal stability of some and the storage stability of all samples. Encapsulation maintained the antioxidant activity of all samples and significantly improved the antiglycation and cellular antioxidant activities of some polyphenols following SD. In conclusion, the formed inclusion complexes of βCD with polyphenols had greater storage stability, without altering the beneficial cellular effects of the polyphenols.

Antioxidant Content and Antioxidant Capacity of the Protein-Rich Powdered Beverages Enriched with Flax Seeds Gum

Powdered beverages produced from dried fruit and vegetables are new products whose properties may be tailored by adding efficient nutrients and functional ingredients. The analyses of low-molecular antioxidants and antioxidant properties as well as nutrient content and digestibility were tested in beverages enriched with lentil proteins (AGF) and flaxseed gum (FSG). A replacement of sprouted lentil flour with the AGF deteriorated the phenolic content. As a main source of phenolics and vitamin C, lyophilized parsley leaves and broccoli sprouts were recognized. (There was no clear effect of the FGS.) The highest content of phenolics was determined in the beverages with these additives without the AGS (c.a. 125 μg/g). The AGF significantly improved the ability to quench ABTS radicals and reduce power. The best results were for the beverages without the FSG. (The effect was enhanced by lyophilized fruit and green vegetables.) The lowest chelating power and ability to quench hydroxyl radicals were in the beverages based on the AGF (improvement by the FSG and green vegetables). The tailoring of beverages' recipes significantly increased protein content and did not affect nutrient digestibility. The modifications allow obtaining the beverages exhibiting multidirectional antioxidant properties, being a source of easily bioaccessible starch and proteins.

Inhibition of α-Amylase and α-Glucosidase of Anthocyanin Isolated from Berberis integerrima Bunge Fruits: A Model of Antidiabetic Compounds

Anthocyanins are components of the flavonoid group with different properties, such as antidiabetic properties. This study aimed to isolate anthocyanin from Berberis integerrima Bunge fruits and evaluate α-amylase and α-glucosidase inhibition by this mentioned anthocyanin. The anthocyanin of Berberis integerrima fruit was isolated using column chromatography, and the antidiabetic properties of the anthocyanin were determined by the levels of α-amylase and α-glucosidase inhibition. Km and Vmax were also evaluated using the GraphPad Prism 7. The results of this study showed that the anthocyanin content of the fruit extract was 14.36 ± 0.33 mg/g, and following purification, this amount increased to 34.51 ± 0.42 mg/g. The highest of α-glucosidase inhibition was observed in the purified anthocyanin with IC₅₀ = 0.71 ± 0.085 mg/ml, compared to acarbose as the baseline with IC₅₀ = 8.8 ± 0.14 mg/ml, p < 0.0001. Purified anthocyanin of the mentioned fruit with IC₅₀ = 1.14 ± 0.003 mg/ml had the greatest α-amylase inhibition, which was similar to acarbose as the standard with IC₅₀ = 1 ± 0.085 mg/ml, p < 0.05. The inhibition of α-glucosidase and α-amylase by purified anthocyanin showed uncompetitive inhibition, and the enzyme inhibition by unpurified anthocyanin showed mixed inhibition. The obtained findings showed that Berberis integerrima fruit can be mentioned as a source of anthocyanin with antidiabetic properties.

Inhibitory Effect of Polyphenols from the Whole Green Jackfruit Flour against α-Glucosidase, α-Amylase, Aldose Reductase and Glycation at Multiple Stages and Their Interaction: Inhibition Kinetics and Molecular Simulations

For the first time, α-glucosidase, α-amylase, aldose reductase, and glycation at multiple stages inhibitory assays were used to explore the antidiabetic potential of whole unripe jackfruit (peel with pulp, flake, and seed). Two polyphenols (phenolic acids) with strong antihyperglycaemic activity were isolated from the methanol extract of whole jackfruit flour (MJ) using activity-guided repeated fractionation on a silica gel column chromatography. The bioactive compounds isolated were identified as 3-(3,4-Dihydroxyphenyl)-2-propenoic acid (caffeic acid: CA) and 4-Hydroxy-3,5-dimethoxybenzoic acid (syringic acid: SA) after various physicochemical and spectroscopic investigations. CA (IC50: 8.0 and 26.90 µg/mL) and SA (IC50: 7.5 and 25.25 µg/mL) were identified to inhibit α-glucosidase and α-amylase in a competitive manner with low Ki values. In vitro glycation experiments further revealed that MJ and its components inhibited each stage of protein glycation as well as the generation of intermediate chemicals. Furthermore, CA (IC50: 3.10) and SA (IC50: 3.0 µg/mL) inhibited aldose reductase effectively in a non-competitive manner, respectively. The binding affinity of these substances towards the enzymes examined has been proposed by molecular docking and molecular dynamics simulation studies, which may explain their inhibitory activities. The found potential of MJ in antihyperglycaemic activity via inhibition of α-glucosidase and in antidiabetic action via inhibition of the polyol pathway and protein glycation is more likely to be related to the presence of the phenolic compounds, according to our findings.

Antidiabetic Activity and In Silico Molecular Docking of Polyphenols from Ammannia baccifera L. subsp. Aegyptiaca (Willd.) Koehne Waste: Structure Elucidation of Undescribed Acylated Flavonol Diglucoside

Chemical investigation of the aerial parts of Ammania aegyptiaca ethanol extract (AEEE) showed high concentrations of polyphenol and flavonoid content, with notable antioxidant activity. Undescribed acylated diglucoside flavonol myricetin 3-O-β-⁴C₁-(6″-O-galloyl glucopyranoside) 7-O-β-⁴C₁-glucopyranoside (MGGG) was isolated from the aerial parts of AEEE, along with four known polyphenols that had not been characterized previously from AEEE. The inhibitory effects of MGGG, AEEE, and all compounds against α-amylase, pancreatic lipase and β-glucosidase were assessed. In addition, molecular docking was used to determine the inhibition of digestive enzymes, and this confirmed that the MGGG interacted strongly with the active site residues of these enzymes, with the highest binding free energy against α-amylase (-8.99 kcal/mol), as compared to the commercial drug acarbose (-5.04 kcal/mol), thus justifying its use in the potential management of diabetes. In streptozotocin (STZ)-induced diabetic rats, AEEE significantly decreased high serum glucose, α-amylase activity and serum liver and kidney function markers, as well as increasing insulin blood level. Moreover, AEEE improved the lipid profile of diabetic animals, increased superoxide dismutase (SOD) activity, and inhibited lipid peroxidation. Histopathological studies proved the decrease in pancreas damage and supported the biochemical findings. These results provide evidence that AEEE and MGGG possess potent antidiabetic activity, which warrants additional investigation.

Application of the INFOGEST Standardized Method to Assess the Digestive Stability and Bioaccessibility of Phenolic Compounds from Galician Extra-Virgin Olive Oil

The INFOGEST standardized method was applied to assess the potential bioaccessibility and bioaccessibility of the phenolic compounds from a Galician extra-virgin olive oil (EVOO). The in vitro digestion model involves three steps and generates two fractions after each one: an aqueous fraction (namely, water phase (Wp)) and an oily fraction (namely, oily phase (Op)). The results showed that secoiridoids were the most abundant family in the Galician EVOO polar fraction, representing 98% of the total phenolic compounds. After oral digestion, phenolic acids and simple phenols were mainly detected in Wp, while lignans and flavonoids were mostly found in Op. After gastric digestion, extensive hydrolysis of secoiridoids was observed to generate free tyrosol, hydroxytyrosol, and hydroxytyrosol acetate. The instability of secoiridoids after intestinal digestion was again responsible for the release of simple phenols, which were mainly recovered in Wp together with flavonoids. In contrast, lignans were stable to duodenal conditions and remained in Op.

Inhibitory Effects of Myricetrin and Dihydromyricetin toward α-Glucosidase and Pancreatic Lipase with Molecular Docking Analyses and Their Interaction

The aim of the current study was to evaluate the interaction effects of myricetrin and dihydromyricetin in inhibiting α-glucosidase and pancreatic lipase at different combination ratios and concentrations and to illuminate the underlying mechanisms of their inhibitions by molecular docking analyses. Results showed that both phenolic compounds possessed good inhibitory effects toward two enzymes in a dose-dependent manner. Myricetrin demonstrated a stronger inhibition against α-glucosidase (IC50, 41.14 ± 2.52 and more than 200 μg/mL, respectively), while dihydromyricetin had a better pancreatic lipase inhibition (IC50, 244.96 ± 4.24 and 373.26 ± 21.36 μg/mL, respectively). Different interaction types were observed when myricetrin and dihydromyricetin inhibited α-glucosidase and pancreatic lipase in combination, which were closely related to the combination ratio and concentration. For α-glucosidase inhibition, synergistic effects were observed at relative low concentrations when the combination ratio of myricetrin to dihydromyricetin was set as 1 : 2, while strong synergistic effects existed at relative high concentrations for pancreatic lipase inhibition. In other combination ratios (1 : 1 or 2 : 1), additive and/or antagonistic effects occurred. Molecular docking analyses showed that myricetrin formed nine hydrogen bonds with α-glucosidase, while only three hydrogen bonds were formed between dihydromyricetin and α-glucosidase. However, these two phenolic compounds had similar hydrogen bonds and hydrophobic interactions with pancreatic lipase. The present study suggested that myricetrin and dihydromyricetin or food materials rich in these two phenolic compounds could be exploited as α-glucosidase and/or pancreatic lipase inhibitors to deal with health problems caused by excessive energy intake, and the combination ratio and concentration of these two phenolic compounds should be considered when producing new functional foods.

Screening of in vitro and in silico α-amylase, α-glucosidase, and lipase inhibitory activity of oxyprenylated natural compounds and semisynthetic derivatives

Metabolic syndrome has several characteristic manifestations, including insulin resistance and dyslipidaemia, that demand therapeutic approaches, such as the inhibition of enzymes involved in nutrient absorption and digestion.This study aimed to evaluate the potential pharmacological use of natural compounds widespread in the plant kingdom and their semisynthetic compounds against target enzymes. Twenty-three oxyprenylated natural compoundswere investigated for their ability to inhibit α-amylase, α-glucosidase, and pancreatic lipase enzymes by in vitro assays. Moreover, in silico molecular docking was performed to analyse their binding capabilities into 3D structures. Farnesyloxyferulic acid, geranyloxyvanillic acid, nelumal A, and geranyloxyferulic acid showed the highest inhibition activity in all three in vitro enzyme assays. Moreover, in silico molecular docking of these four compounds was used to analyse their possible binding in 3D structures of the investigated enzymes. The results indicate that these compounds have considerable therapeutic potential for the treatment of metabolic syndrome, and further studies are warranted for their pharmacological development.

Encapsulation of sea buckthorn (Hippophae rhamnoides L.) leaf extract via an electrohydrodynamic method

Polyphenols from the leaves of sea buckthorn (Hippophae rhamnoides L.) are nutritious and bioactive substances that can be used as nutritional supplements. To improve their stability and bioaccessibility in vivo, chemical extracts of sea buckthorn leaves were, for the first time, encapsulated using electrohydrodynamic technology. The microcapsules were characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analysis. The extract and microcapsules were evaluated for total phenols and flavonoids, total antioxidant activity, and their inhibitory effects on metabolic syndrome-related enzymes (α-glucosidase, α-amylase, and pancreatic lipase) under in vitro simulated digestion. The results indicated that the extract was successfully encapsulated; encapsulation protected polyphenols and flavonoids from degradation and increase their bioaccessibility in the intestine. The antioxidant activity and the inhibition of metabolic syndrome-related enzymes were better reserved after encapsulation. Our findings will help in promoting the potential of sea buckthorn as a nutritional supplement and expanding its commercial use.

Using polyphenols as a relevant therapy to diabetes and its complications, a review

Diabetes is currently a worldwide health concern. Hyperglycemia, hypertension, obesity, and oxidative stress are the major risk factors that inevitably lead to all the complications from diabetes. These complications severely impact the quality of life of patients, and they can be managed, reduced, or even reverted by several polyphenols, plant extracts and foods rich in these compounds. The goal of this review is to approach diabetes not as a single condition but rather an interconnected combination of risk factors and complications. This work shows that polyphenols have multi target action and effects and they have been systematically proven to be relevant in the reduction of each risk factor and improvement of associated complication.

Antidiabetic potential of dietary polyphenols: A mechanistic review

Diabetes is a metabolic disorder that has caused enormous harm to the public health worldwide. In this study, we evaluated the potential of phenolic compounds on diabetes management, addressing their mechanisms of action, in addition to discussing the digestion, absorption, metabolism, bioavailability, and toxic effects of these compounds. The intake of phenolic compounds can play a fundamental role on diabetes management, since they can reduce blood glucose levels, oxidative stress, protein glycation, inhibit the activity of dipeptidyl peptidase - IV and other key enzymes related to carbohydrate metabolism, activate various biochemical pathways to improve pancreatic β-cell functions, increase insulin secretion, and improve insulin resistance. In this way, they can be considered a potential strategy in the development of pharmaceutical approaches that aim to reduce complications resulting from the progression of this metabolic pathology.

Extraction and purification of total flavonoids from Eupatorium lindleyanum DC. and evaluation of their antioxidant and enzyme inhibitory activities

The health benefits and promising medical treatment potential of total flavonoids from Eupatorium lindleyanum DC. (TFELDC) have been recognized. The process parameters of extracting total flavonoids from Eupatorium lindleyanum DC. by ultrasonic-microwave synergistic extraction (UMSE) were optimized, and they were purified by AB-8 macroporous resin in the current study. In addition, the antioxidant and enzyme inhibitory activities of the purified TFELDC (PTFELDC) were evaluated. The results showed that the optimal parameters of UMSE were as follows: ethanol volume fraction 71.5%, L/S ratio 12.2 ml/g, microwave power 318 W, and extraction time 143 s. After TFELDC were purified by AB-8 macroporous resin, the total flavonoid contents of PTFELDC increased from 208.18 ± 1.60 to 511.19 ± 3.21 mg RE/g FDS. Compared with TFELDC, the content of total flavonoids in PTFELDC was increased by 2.46 times. The antioxidant activities of PTFELDC were assessed using DPPH radical, superoxide anion radical, reducing power, and ferric reducing antioxidant power assays, and the IC50 values were found to be 37.13, 19.62, 81.22, and 24.72 μg/ml, respectively. The enzyme inhibitory activities of PTFELDC were measured using lipase, α-amylase, α-glucosidase, and acetylcholinesterase assays with the IC50 values 1.38, 2.08, 1.63, and 0.58 mg/ml, respectively. By comparing with their positive controls, it was found that PTFELDC had good antioxidant activities, and lipase, α-amylase, and α-glucosidase inhibitory activities, However, the acetylcholinesterase inhibitory activity was relatively weaker. These results suggested that PTFELDC have a promising potential as natural antioxidant, antilipidemic, and hypoglycemic drugs used in functional foods or pharmaceuticals.

Current status of the gastrointestinal digestion effects on honey: A comprehensive review

In the past five years, more than 8000 scientific reports have been published on honey composition and its potential bioactivity as a source of pro-health components. However, the potential effectiveness of nutrients and other compounds in the human body is greatly influenced by the individual digestion conditions. Consequently, changes in the structure of honey components and their interactions with other constituents are expected and they may affect the bioaccessibility, the bioavailability, and further physiological functions of honey nutrients and bioactives. In this context, in addition to present key physiological characteristics for each step of the human digestion and their simulation aspects, this review also summarizes and discusses available data regarding the effect of the digestion (in vitro and in vivo) on honey compounds. Additionally, we consider the influence of the digestion on biological activities described for the compounds in the honey.

Assessing the In Vitro Inhibitory Effects on Key Enzymes Linked to Type-2 Diabetes and Obesity and Protein Glycation by Phenolic Compounds of Lauraceae Plant Species Endemic to the Laurisilva Forest

Methanolic leaf extracts of four Lauraceae species endemic to Laurisilva forest (Apollonias barbujana, Laurus novocanariensis, Ocotea foetens and Persea indica) were investigated for the first time for their potential to inhibit key enzymes linked to type-2 diabetes (α-amylase, α-glucosidase, aldose reductase) and obesity (pancreatic lipase), and protein glycation. Lauraceae extracts revealed significant inhibitory activities in all assays, altough with different ability between species. In general, P. indica showed the most promissing results. In the protein glycation assay, all analysed extracts displayed a stronger effect than a reference compound: aminoguanidine (AMG). The in vitro anti-diabetic, anti-obesity and anti-glycation activities of analysed extracts showed correlation with their flavonols and flavan-3-ols (in particular, proanthocyanins) contents. These Lauraceae species have the capacity to assist in adjuvant therapy of type-2 diabetes and associated complications, through modulation of the activity of key metabolic enzymes and prevention of advanced glycation end-products (AGEs) formation.

Phenolic compounds, bioactivity, and bioaccessibility of ethanol extracts from passion fruit peel based on simulated gastrointestinal digestion

Passion fruit peel, a potential source of bioactive compounds, has been used as food stabilizing agent. However, the phenolic composition and bioactivity of passion fruit peel have rarely been reported. The effects of simulated gastrointestinal digestion on the bioactive components, bioactivity and bioaccessibility of passion fruit peel ethanol extracts (PFPE) were investigated using high performance liquid chromatography-tandem mass spectrometry analysis (quasi-targeted metabolomics). Phenols (178) were identified, of which 25 inhibited alpha-glucosidase activity. The stabilities of PFPE phenols were significantly affected by pH changes and digestive enzymes during simulated digestion. The 1,1-diphenyl-2-picrylhydrazyl free radical scavenging capacity and ferric ion reducing antioxidant power were decreased by 32% and 30%, respectively, while 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) free radical scavenging capacity increased by 17%. Alpha-glucosidase inhibition decreased with decreased PFPE phenolic content. Therefore, passion fruit peel could be considered a source of natural antioxidants and alpha-glucosidase inhibitors.

Health Potential of Clery Strawberries: Enzymatic Inhibition and Anti-Candida Activity Evaluation

Strawberries, belonging to cultivar Clery (Fragaria × ananassa Duchesne ex Weston) and to a graft obtained by crossing Clery and Fragaria vesca L., were chosen for a study on their health potential, with regard to the prevention of chronic and degenerative diseases. Selected samples, coming from fresh and defrosted berries, submitted to different homogenization techniques combined with thermal and microwave treatments, had been previously analyzed in their polyphenolic content and antioxidant capacity. In the present work, these homogenates were evaluated in relation to their enzymatic inhibition activity towards acetylcholinesterase and butyrylcholinesterase, α-amylase, α-glucosidase and tyrosinase. All these enzymes, involved in the onset of diabetes, and neurodegenerative and other chronic diseases, were modulated by the tested samples. The inhibitory effect on tyrosinase and cholinesterase was the most valuable. Antifungal activity against Candida albicans, recently shown to play a crucial role in human gut diseases as well as diabetes, rheumatoid arthritis and Alzheimer’s disease, was also shown in vitro and confirmed by the in vivo text on Galleria mellonella. Overall, the obtained results confirm once again the health potential of strawberries; however, the efficacy is dependent on high quality products submitted to correct processing flow charts.

Green and Sustainable Valorization of Bioactive Phenolic Compounds from Pinus By-Products

In Europe, pine forests are one of the most extended forests formations, making pine residues and by-products an important source of compounds with high industrial interest as well as for bioenergy production. Moreover, the valorization of lumber industry residues is desirable from a circular economy perspective. Different extraction methods and solvents have been used, resulting in extracts with different constituents and consequently with different bioactivities. Recently, emerging and green technologies as ultrasounds, microwaves, supercritical fluids, pressurized liquids, and electric fields have appeared as promising tools for bioactive compounds extraction in alignment with the Green Chemistry principles. Pine extracts have attracted the researchers’ attention because of the positive bioproperties, such as anti-inflammatory, antimicrobial, anti-neurodegenerative, antitumoral, cardioprotective, etc., and potential industrial applications as functional foods, food additives as preservatives, nutraceuticals, pharmaceuticals, and cosmetics. Phenolic compounds are responsible for many of these bioactivities. However, there is not much information in the literature about the individual phenolic compounds of extracts from the pine species. The present review is about the reutilization of residues and by-products from the pine species, using ecofriendly technologies to obtain added-value bioactive compounds for industrial applications.

Integral use of Argentinean Solanum betaceum red fruits as functional food ingredient to prevent metabolic syndrome: effect of in vitro simulated gastroduodenal digestion

The "red chilto" (Solanum betaceum Cav) is a native fruit from the Yungas forest of Argentina. Red chilto is a neglected and underutilized native species (NUS). The objective of this work was to evaluate the potentiality of pulp, seed and skin from "red chilto" as a functional food ingredient to add value to a native resource of Argentine Yungas to promote sustainable integral use of it. The powders have low carbohydrate and sodium content and are a source of vitamin C, phenolic acids (rosmarinic acid and caffeoylquinic acid), anthocyanins, condensed tannins, carotenoids, potassium, and fiber. The phenolics of chilto powders showed, before and after simulated gastroduodenal digestion, antioxidant activity (ABTS•+; H2O2; O2 •; HO•) and were able to inhibit enzymes related to metabolic syndrome, such as α-glucosidase, α-amylase and lipase. Chilto powder showed hypoglycemic effect by increasing glucose adsorption, decreasing glucose diffusion rate and by promoting glucose transport across the cell membrane. These results suggest the potential of Argentinean "red chilto" fruits as functional food ingredients or dietary supplements to prevent metabolic syndrome principally by its antioxidant, hypoglycemic and hypolipemic effects.