Search Results (407)

Background: Dietary polyphenols, particularly flavonoids, have been associated with improved glycemic control and reduced risk of type 2 diabetes. Raspberry leaf (RL) is a rich but underexplored source of such bioactives, including ellagitannins, flavonoids, and phenolic acids. While raspberry fruit has received some attention in nutritional science, the metabolic effects of raspberry leaf—especially its influence on postprandial glucose and insulin responses—remain largely unstudied. Objective: This study is the first to investigate the acute effects of RL tea consumption on postprandial blood glucose and insulin levels in healthy individuals following intake of common dietary carbohydrates (sucrose and glucose). Methods: In a randomized crossover study, 22 healthy adults (12 males, 10 females) consumed 50 g of glucose or sucrose with or without 10 g of RL tea in four separate sessions. Blood glucose and insulin levels were measured at fasting and at 15, 30, 60, 90, and 120 min post-ingestion. A total of 37 polyphenolic compounds were identified in the RL infusion using LC–MS, following a 5-minute hot water extraction. The contents of ellagitannins, flavonoids, and phenolic acids were 38 mg, 7 mg, and 4 mg per 10 g of RL, respectively, contributing to a total polyphenol content of 50 mg per 10 g. Results: When RL tea was consumed with sucrose, postprandial blood glucose levels were significantly reduced at 15 and 30 min by 1.19 ± 0.88 mmol/L (25.59% reduction, p = 0.001) and 2.03 ± 1.05 mmol/L (43.57% reduction, p = 0.0004), respectively. Insulin concentrations were also significantly lower at 15 min (113.90 ± 59.58 pmol/L, p = 0.019), 30 min (161.76 ± 91.96 pmol/L, p = 0.0008), and 60 min (139.44 ± 75.96 pmol/L, p = 0.025). No significant differences were observed with glucose ingestion. Conclusions: This study provides the first clinical evidence that RL tea can blunt early postprandial glycemic and insulinemic responses to sucrose in healthy individuals. The data suggest that these effects are likely mediated by relatively low levels of polyphenols—particularly ellagic acid—through inhibition of carbohydrate-digesting enzymes such as α-glucosidase and β-fructofuranosidase. These findings support the potential of RL tea as a simple, dietary approach to modulate glucose metabolism and warrant further investigation in populations at risk for metabolic disorders. Full article

Background/Objectives: Diabetes mellitus (DM) is one of the most common metabolic disorders, with a continually increasing population incidence. One of the main therapeutic approaches for this condition involves the inhibition of alpha-amylase and alpha-glucosidase—key enzymes involved in carbohydrate breakdown. Silver nanoparticles have exhibited inhibitory activity against both enzymes, suggesting their potential in regulating postprandial blood glucose levels. This study aimed to evaluate the antidiabetic potential of silver nanoparticles biosynthesized with Stenocereus queretaroensis flower extract. Methods: The flower extract was prepared and, following a qualitative and quantitative phytochemical analysis, was utilized in the reaction to biosynthesize S. queretaroensis flower extract nanoparticles (SAgNPs). The SAgNPs were characterized using UV–visible spectroscopy, dynamic light scattering (DLS), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), and Fourier transform infrared spectrophotometry (FTIR). The antidiabetic potential of the biosynthesized SAgNPs was evaluated in vitro using alpha-amylase and alpha-glucosidase inhibitory assays, while an animal model was used for postprandial hypoglycemic activity in healthy mice. Results: The phytochemical analyses showed the presence of phenolic compounds and flavonoids like sinapic acid, p-coumaroyl tyrosine, procyanidin dimer β1, and dihydroquercetin in the flower extract. The SAgNPs were found to be rough and spherical in shape, with an average size of 99.5 nm. The inhibition of alpha-amylase and alpha-glucosidase by SAgNPs exhibited an IC₅₀ of 4.92 µg/mL and 0.68 µg/mL, respectively. The animal model results suggested that SAgNPs at 100 mg/kg caused a significant decrease in the postprandial glucose level; this effect is likely attributable to delayed carbohydrate digestion, as supported by the in vitro findings. Conclusions: S. queretaroensis-synthesized silver nanoparticles may constitute a promising option for antidiabetic therapy. Full article

Chlorophyll, the green pigment essential for photosynthesis, abundantly found in green vegetables and algae, has attracted growing scientific interest for its potential therapeutic effects, particularly in diabetes management. Recent research highlighted that chlorophyll and its derivatives may beneficially influence glucose metabolism and oxidative stress, key factors in diabetes. This review examines current knowledge on how chlorophyll compounds could aid diabetes control. Chlorophyll and its derivatives appear to support glucose regulation primarily through actions in the gastrointestinal tract. They modulate gut microbiota, improve glucose tolerance, reduce inflammation, and alleviate obesity-related markers. While chlorophyll itself does not directly inhibit digestive enzymes like α-glucosidase, its derivatives such as pheophorbide a, pheophytin a, and pyropheophytin a may slow carbohydrate digestion, acting as α-amylase and α-glucosidase inhibitors, reducing postprandial glucose spikes. Additionally, chlorophyll enhances resistant starch content, further controlling glucose absorption. Beyond digestion, chlorophyll derivatives show promise in inhibiting glycation processes, improving insulin sensitivity through nuclear receptor modulation, and lowering oxidative stress. However, some compounds pose risks due to photosensitizing effects and toxicity, warranting careful consideration. Chlorophyllin, a stable semi-synthetic derivative, also shows potential in improving glucose and lipid metabolism. Notably, pheophorbide a demonstrates insulin-mimetic activity by stimulating glucose uptake via glucose transporters, offering a novel therapeutic avenue. Overall, the antioxidant, anti-inflammatory, and insulin-mimicking properties of chlorophyll derivatives suggest a multifaceted approach to diabetes management. While promising, these findings require further clinical validation to establish effective therapeutic applications. Full article

Bioactive phenolic compounds released in the digestive tract have the potential to mitigate various diseases. However, they can be affected by dietary fibers. Our aim was to study the influence of β-glucan (dietary fiber) on the antiradical activity of phenolic compounds from chokeberry and its inhibition of α-amylase and α-glucosidase after digestion. These beneficial activities, helpful in many health issues connected to the digestive tract, depend on the constituents of food, such as dietary fibers, that surround these compounds and are not completely elucidated. Simulated digestion of chokeberry with or without the presence of β-glucan was conducted in vitro. The released phenolic compounds (RP-HPLC method), the antiradical activity (DPPH method), and the inhibition of α-amylase and α-glucosidase were determined after digestion. Chokeberry after gastric and intestinal digestion showed antiradical activity, and after intestinal digestion, it inhibited α-amylase and α-glucosidase. B-glucan decreased the amount of total phenolic compounds released (1800 to 1761 mg kg⁻¹ fw) and bioaccessibility (60 to 59%) in the stomach (p < 0.05) and small intestine (1738 to 1637 mg kg⁻¹ fw, 58 to 55%) (p < 0.05), decreased the antiradical activity, and weakened the enzyme inhibition. Principal component analysis clustered the released phenolic compounds and beneficial effects according to digestion with or without added β-glucan, confirming the influence of β-glucan on beneficial effects. Chokeberry polyphenols kept their beneficial effects in the stomach and small intestine in the presence of dietary fiber, which allows us to suggest that they show bioactivities even in the presence of other food constituents. Full article

Background/Objectives: Essential amino acid (EAA) supplementation is often employed in sportive and clinical nutrition due to EAAs’ role in muscle mass maintenance and growth. EAAs are also involved in insulin and glucagone regulation in diabetes management, but only few reports investigate their possible implication as dipeptidyl peptidase-IV (DPP-IV) inhibitors and their effect on the stability and secretion of enteroendocrine hormones. A blend of EAAs (called GAF) available as a food supplement, in a specific qualitative and quantitative ratio, was investigated to address its in vitro bioaccessibility, its hypoglycemic properties in vitro and in situ on cellular models, and its safety on intestinal Caco-2 cells. Methods: GAF was subjected to the INFOGEST static digestion protocol, producing the iGAF sample. iGAf DPP-IV inhibitory properties were investigated both in vitro and in situ on Caco-2 cells. Then, STC-1 enteroendocrine cells were employed alone and in co-culture with Caco-2 cells to evaluate iGAF’s impact on glucagon-like peptide 1 (GLP-1) hormone secretion. Results: The study demonstrates that the present EAAs blend is stable and bioaccessible after simulated gastrointestinal digestion, and it is safe at the intestinal cellular level. It inhibits DPP-IV enzyme both in vitro and in situ and promotes GLP-1 secretion by enteroendocrine cells. Conclusions: The sample demonstrated safety at the intestinal level and showed hypoglycemic properties by acting on a dual synergic mechanism that involves DPP-IV enzyme inhibition and GLP-1 hormone stimulation. Full article

The growing demand for sustainable plant-based dairy alternatives has spurred interest in valorizing agro-industrial byproducts like hazelnut cake, a protein-rich byproduct of oil extraction. This study developed formulations for vegan ice cream using unfermented (HIC) and Aspergillus oryzae-fermented hazelnut cake (FHIC), comparing their physicochemical, functional, and sensory properties to conventional dairy ice cream (DIC). Solid-state fermentation (72 h, 30 °C) enhanced the cake’s bioactive properties, and ice creams were characterized for composition, texture, rheology, melting behavior, antioxidant activity, and enzyme inhibition pre- and post-in vitro digestion. The results indicate that FHIC had higher protein content (64.64% vs. 58.02% in HIC) and unique volatiles (e.g., benzaldehyde and 3-methyl-1-butanol). While DIC exhibited superior overrun (15.39% vs. 4.01–7.00% in vegan samples) and slower melting, FHIC demonstrated significantly higher post-digestion antioxidant activity (4.73 μmol TE/g DPPH vs. 1.44 in DIC) and angiotensin-converting enzyme (ACE) inhibition (4.85–7.42%). Sensory evaluation ranked DIC highest for overall acceptability, with FHIC perceived as polarizing due to pronounced flavors. Despite textural challenges, HIC and FHIC offered nutritional advantages, including 18–30% lower calories and enhanced bioactive compounds. This study highlights fermentation as a viable strategy to upcycle hazelnut byproducts into functional vegan ice creams, although the optimization of texture and flavor is needed for broader consumer acceptance. Full article

Sprouted grains are gaining attention as a natural and sustainable source of bioactive compounds with potential benefits in managing insulin resistance (IR), a hallmark of obesity-related metabolic disorders. This review aims to synthesize current findings on the biochemical changes induced during grain germination and their relevance to metabolic health. We examined recent in vitro, animal, and human studies focusing on how germination enhances the nutritional and functional properties of grains, particularly through the synthesis of compounds such as γ-aminobutyric acid, polyphenols, flavonoids, and antioxidants, while reducing anti-nutritional factors. These bioactive compounds have been shown to modulate metabolic and inflammatory pathways by inhibiting carbohydrate-digesting enzymes, suppressing pro-inflammatory cytokines, improving redox balance, and influencing gut microbiota composition. Collectively, these effects contribute to improved insulin sensitivity and glycemic control. The findings suggest that sprouted grains serve not only as functional food ingredients but also as accessible dietary tools for preventing or alleviating IR. Their role in delivering multiple bioactive molecules through a simple, environmentally friendly process highlights their promise in developing future nutrition-based strategies for metabolic disease prevention. Full article

Anaerobic digestion (AD) has long been valued for producing a biogas–digestate pair, yet its profitability is tightening. Next-generation AD biorefineries now position syngas both as a supplementary feedstock and as a springboard to capture high-value intermediates, hydrogen (H₂) and volatile fatty acids (VFA). This review dissects how complex natural consortia “decide” between hydrogenogenesis and acetogenesis when CO, H₂, and CO₂ co-exist in the feedstocks, bridging molecular mechanisms with process-scale levers. The map of the bioenergetic contest between the biological water–gas shift reaction and Wood–Ljungdahl pathways is discussed, revealing how electron flow, thermodynamic thresholds, and enzyme inhibition dictate microbial “decision”. Kinetic evidence from pure and mixed cultures is integrated with practical operating factors (gas composition and pressure, pH–temperature spectrum, culture media composition, hydraulic retention time, and cell density), which can bias consortia toward the desired product. Full article

Soybean meal (SBM) is extensively used as a predominant protein source in animal feed. However, raw soybean cannot be directly utilized in animal feed, due to the presence of the Kunitz trypsin inhibitor (KTi) and the Bowman–Birk protease inhibitor (BBi). These antinutritional factors inhibit the digestive enzymes in animals, trypsin and chymotrypsin, resulting in poor animal performance. To inactivate the activity of protease inhibitors, SBM is subjected to heat processing, a procedure that can negatively impact the soybean protein quality. Thus, it would be beneficial to develop soybean varieties with little or no trypsin inhibitors. In this study, we report on the creation of experimental soybean lines with significantly reduced levels of Bowman–Birk protease inhibitors. RNA interference (RNAi) technology was employed to generate several transgenic soybean lines. Some of these BBi knockdown soybean lines showed significantly lower amounts of both trypsin and chymotrypsin inhibitor activities. Western blot analysis revealed the complete absence of BBi in selected RNAi-derived lines. RNA sequencing (RNAseq) analysis demonstrated a drastic reduction in the seed-specific expression of BBi genes in the transgenic soybean lines during seed development. Confocal fluorescence immunolabeling studies showed that the accumulation of BBi was drastically diminished in BBi knockdown lines compared to wild-type soybeans. The absence of BBi in the transgenic soybean did not alter the overall protein, oil, and sulfur amino acid content of the seeds compared to wild-type soybeans. The seed protein from the BBi knockdown lines were more rapidly hydrolyzed by trypsin and chymotrypsin compared to the wild type, indicating that the absence of BBi enhances protein digestibility. Our study suggests that these BBi knockdown lines could be a valuable resource in order for plant breeders to incorporate this trait into commercial soybean cultivars, potentially enabling the use of raw soybeans in animal feed. Full article

This study investigated the functional potential of Campomanesia xanthocarpa leaf and fruit infusions through phytochemical profiling, simulated gastrointestinal digestion, enzyme inhibition assays, and in vivo evaluation of glycemic markers. Leaf infusions exhibited a more diverse phenolic profile, higher total phenolic content, and greater antioxidant capacity compared to fruit infusions. Simulated digestion confirmed the bioaccessibility of key phenolic compounds, particularly glycosylated flavonoids such as quercetin-3-glucoside and kaempferol derivatives, with leaf extracts showing superior gastrointestinal stability. In vitro assays revealed a strong inhibitory activity of leaf infusions against α-amylase and β-glucosidase. In a 32-day trial with healthy dogs, the consumption of biscuits enriched with leaf infusion did not alter fasting glucose or amylase levels but resulted in a significant treatment × time interaction for serum fructosamine, indicating a delayed modulation of glycemic control, potentially associated with antioxidant or anti-glycation activity. These findings highlight the potential of C. xanthocarpa leaves as a functional ingredient in foods aimed at supporting glycemic regulation and metabolic health. Full article

Rapeseed meal, a byproduct of oil extraction, is increasingly recognised as a valuable source of plant protein and health-promoting peptides. This study aimed to identify key proteins in cold-pressed rapeseed meal and assess their potential to release bioactive peptides through in silico hydrolysis using plant-derived proteases, namely papain, bromelain, and ficin. Proteomic profiling via two-dimensional electrophoresis and MALDI-TOF/TOF mass spectrometry revealed cruciferin as the dominant protein, along with other metabolic and defence-related proteins. In silico digestion of these sequences using the BIOPEP database generated thousands of peptide fragments, of which over 50% were predicted to exhibit bioactivities, including ACE and DPP-IV inhibition, as well as antioxidant, neuroprotective, and anticancer effects. Among the evaluated enzymes, bromelain exhibited the highest efficacy, yielding the greatest quantity and diversity of bioactive peptides. Notably, peptides with antihypertensive and antidiabetic properties were consistently identified across all of the protein and enzyme variants. Although certain rare functions, such as anticancer and antibacterial activities, were observed only in specific hydrolysates, their presence underscores the broader functional potential of peptides derived from rapeseed. These findings highlight the potential of rapeseed meal as a sustainable source of functional ingredients while emphasising the necessity for experimental validation to confirm the predicted bioactivities. Full article

Background: The New Zealand pine bark has been demonstrated in vitro to inhibit digestive enzymes involved in carbohydrate digestion (alpha-amylase, alpha-glucosidase, and dipeptidyl-peptidase 4 (DPP-4)). Objective: This study aims to investigate the inhibitory effects of the New Zealand pine bark on sucrose uptake and glycaemic responses in humans. Methods: A single-blind, randomised, placebo-controlled, crossover trial was carried out involving healthy adults (n = 40 (M: 12, F: 28), 30.1 ± 1.3 years, BMI 23.4 ± 0.5 kg/m², HbA1c 32.5 ± 0.6 mmol/mol, FBG 4.7 ± 0.1 mmol/L). A control (75 g of sucrose powder only), and two doses of the pine bark extract (50 and 400 mg) were provided on separate occasions, with 75 g of sucrose mixed in 250 mL of water. Blood samples were collected at −10, 0, 15, 30, 45, 60, 90, and 120 min via a finger prick test. A linear mixed model for repeated measures (SPSS v30, IBM) was applied, and data presented as model-adjusted mean ± SEM. Results: Compared to control (247.5 ± 14.0 mmol/L⋅min), the iAUCglucose was significantly reduced with the 400 mg dose (211.8 ± 13.9 mmol/L⋅min, 14.4% reduction, and p = 0.037), but not with 50 mg dose (220.8 ± 14.2 mmol/L⋅min, 10.8% reduction, and p = 0.184). Compared to control (9.1 ± 0.2 mmol/L), glucose peak value was significantly reduced with the 50 mg dose (8.6 ± 0.2 mmol/L, 5.5% reduction, and p = 0.016) but not with the 400 mg dose (8.7 ± 0.2 mmol/L, 4.4% reduction, and p = 0.093). There were no statistically significant changes in postprandial insulin levels with the pine bark extract compared to control. Conclusions: The New Zealand pine bark extract attenuated sucrose uptake with improved glycaemic responses, and may therefore be useful as a hypoglycaemic adjunct to the diet. Full article

Angiotensin-converting enzyme 2 (ACE2) is a cell-surface receptor that helps the body regulate blood pressure and endocrine secretions. Transmembrane serine protease 2 (TMPRSS2) is a cell surface protein expressed mainly by endothelial cells of the respiratory and digestive tract, which participates in the cleavage of protein peptide bonds with serine as the active site. These two proteins have been studied to be highly associated with infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Soybean trypsin inhibitor (SBTI) has special bioactivities such as anticarcinogenic and anti-inflammatory functions, which can be widely used in functional foods or drugs. Our study involved in vitro and in vivo experiments to elucidate the effect of SBTI on SARS-CoV-2 host invasion. First, it was confirmed that being under 250 μg/mL of SBTI was not toxic to HepG2, HEK293T, and Calu-3 cells. The animal study administered SBTI to mice once daily for 14 days. In the lungs, liver, and kidneys, the histopathologic findings of the SBTI group were not different from those of the control group, but the expression of ACE2, TMPRSS2, and CD147 was reduced. Thus, our findings suggest that the inhibition of ACE2, TMPRSS,2 and CD147 proteins by SBTI shows promise in potentially inhibiting SARS-CoV-2 infection. Full article

This study investigated the ecotoxicological impacts of environmentally relevant concentrations (0.05, 0.50, and 5.00 mg/L) of nickel nanoparticles (Ni-NPs) by assessing oxidative stress biomarkers. The worm Hediste diversicolor, the bivalve Mytilus spp., and the fish Sparus aurata were chronically exposed to Ni-NPs for 28 days, and glutathione S-transferases (GST), catalase (CAT), and thiobarbituric acid reactive substances (TBARS) levels were measured to evaluate biochemical responses. GST activity increased in H. diversicolor and the liver of S. aurata, suggesting a key role for this enzyme in Ni-NPs detoxification. CAT activity was inhibited in the digestive gland of Mytilus spp. at the highest Ni-NPs concentration, indicating possible disruption of antioxidant defense. TBARS levels rose significantly in the gills of Mytilus spp. exposed to high Ni-NP concentrations, suggesting oxidative damage beyond detoxification capacity. In contrast, TBARS decreased in the digestive gland of Mytilus and in H. diversicolor, possibly due to compensatory upstream antioxidant responses. These findings indicate that each species exhibits distinct adaptive responses to Ni-NP exposure. Overall, this study highlights the need to consider species- and tissue-specific responses when performing ecotoxicological risk assessments of nanomaterials. Full article

Edible flowers are gaining recognition as rich sources of nutrients and phytochemicals. In Mexico, the flower of Agave inaequidens has been traditionally consumed since pre-Hispanic times. This study investigated its nutritional profile and the in vitro gastrointestinal bioaccessibility of its phenolic fraction. During in vitro digestion (oral, gastric, and intestinal), the total phenolic content of A. inaequidens significantly decreased from 138 to 21 mg GAE/100 g DW (15.22% bioaccessibility), while total flavonoid content dropped from 8 to 4.6 mg CE/100 g DW (57.5% bioaccessibility). Consequently, antioxidant activity, assessed by ABTS, DPPH, and hemolysis inhibition assays, also declined post-digestion. Interestingly, the digestive process modulated the flower’s inhibitory activity against digestive enzymes before and after in vitro digestion: α-amylase inhibition slightly decreased (IC₅₀ 1.8 to 2.1 mg/mL), but α-glucosidase (IC₅₀ 2.7 to 1.6 mg/mL) and lipase (IC₅₀ > 3 to 1.4 mg/mL) inhibition increased. The A. inaequidens flower is a good source of fiber and low in fat. These findings underscore its potential as a functional food ingredient, offering bioaccessible phenolic compounds with antioxidant and enzyme inhibitory properties. Full article