Pancreatic Α-amylase Research Articles

Anti-Obesity Potentials of Methanol Extracts of Phragmanthera Incana Leaves Hemi-Parasitic on Guava, Cashew, Kolanut and Mango Trees in High-Fat Diet-Induced Obese Rats

The anti-obesity potential of methanol extracts of Phragmanthera incana leaves hemi-parasitic on guava Psidium guajava (PIPG), cashew Anacardium occidentale (PIAO), mango Mangifera indica (PIMI) and kolanut Cola acuminata (PICA) trees were evaluated. Thirty high-fat diet-induced rats were grouped into six; four experimental, negative control and positive controls were orally administered lipid emulsion (5 mL/kg). Experimental received 400 mg/kg body weight from each of the four methanol extracts in addition to the lipid emulsion, positive control received 120 mg/kg bw Orlistat in addition to lipid emulsion while negative control received lipid emulsion alone. Blood samples were collected from ophthalmic venous plexus at 0, 90, and 180 minutes to determine plasma pancreatic lipase (PL) activity, alpha amylase activity and lipid profiles. PL inhibitory activity of the four methanol extracts showed that methanol extracts of PICA and PIAO had greater than 50% inhibition at 400 µg/mL. The α-amylase inhibitory activity of PICA was significantly higher (p < 0.05) when compared with PIAO, PIPG and PIMI. A significant decrease (p < 0.05) in total cholesterol, low density Lipoprotein-cholesterol levels and atherogenic index of plasma of PICA when compared with other treatment groups after 180 minutes of extracts administration was observed. Methanol extract of PICA was found to exhibit higher inhibitory pancreatic lipase and α-amylase activities and higher hypocholesterolemic activity when compared with those of guava (PIPG), cashew (PIAO) and mango (PIMI). This indicates that methanol extract of P. incana leaves could serve as a source of phyto-compounds that could be developed as antiobesity drugs.

The Phenolic Content of Pistacia lentiscus Leaf Extract and Its Antioxidant and Antidiabetic Properties.

The aims of this study were to determine the polyphenolic profile, to estimate the total phenolic and flavonoid contents, and to evaluate the antioxidant and antidiabetic activities of the extract of Pistacia lentiscus leaves, and the hydroacetonic mixture was employed as an alternative for common solvents in the extraction process. In order to explain the antidiabetic activity, molecular docking has been performed on the main constituents of the leaf extract. The characterization of the extract has been performed by high-performance liquid chromatography (HPLC) leading to the detection of 20 compounds of which gallic acid, ellagic acid, catechin, kaempferol, and quercetin 3-glucoside were identified using authentic standards. The total phenolic and flavonoid contents, assessed using the Folin-Ciocalteu and quercetin methods, were 394.5 ± 0.08 mg gallic acid equivalent/g dry extract (mg GAE/g DE) and 101.2 ± 0.095 mg quercetin equivalent/g dry extract (mg QE/g DE), respectively. On the other hand, the antioxidant activity of leaf extract, quantified by determining the ability to neutralize the free radical DPPH and β-carotene/linoleate model system, reached the values of 0.0027 ± 0.002 mg/mL and 0.128 ± 0.04 mg/mL, respectively. Regarding the antidiabetic activity, based on the inhibition of pancreatic α-amylase activity, a significant inhibition of about 68.20% with an IC50 value of 0.266 mg/mL had been observed. This finding is consistent with the molecular docking study of the main phenolic compounds of the extracts, where a remarkable binding affinity against α-amylase was observed, with values of -7.631 (kcal/mol), -6.818 (kcal/mol), and -5.517 (kcal/mol) for the major compounds catechin, quercetin-3-glucoside, and gallic acid, respectively.

Two rare flavonoid glycosides from Litsea glutinosa (Lour.) C. B. Rob.: experimental and computational approaches endorse antidiabetic potentiality

BackgroundLitsea glutinosa (Lour.) C. B. Rob. belongs to the Litsea genus and is categorized under the family of Lauraceae. The study aimed to investigate the phytoconstituents and pharmacological properties of methanol extract of leaves of Litsea glutinosa, focusing on antidiabetic activity via in vivo and in silico techniques.MethodsExtensive chromatographic and spectroscopic techniques were applied to isolate and characterize the constituents from the L. glutinosa plant species. The antidiabetic activity was studied in streptozotocin-induced diabetes mice, and the computational study of the isolated compounds was carried out by utilizing AutoDock Vina programs. In addition, the pharmacokinetic properties in terms of absorption, distribution, metabolism and excretion (ADME) and toxicological profiles of the isolated compounds were examined via in silico techniques.ResultsIn the present study, two flavonoid glycosides 4΄-O-methyl (2 ̋,4 ̋-di-E-p-coumaroyl) afzelin (1) and quercetin 3-O-(2 ̋,4 ̋-di-E-p-coumaroyl)-α-L-rhamnopyranoside (2) were isolated from the leaves of L. glutinosa and characterized by 1H and 13C NMR, COSY, HSQC, HMBC, and mass spectral data. Although compounds 1 and 2 have been reported twice from Machilis litseifolia and Lindera akoensis, and Machilis litseifolia and Mammea longifolia, respectively, this is the first report of this isolation from a Litsea species. Administering the methanolic extract of L. glutinosa at doses of 300 and 500 mg/kg/day to mice with diabetes induced by streptozotocin led to a significant decrease in fasting blood glucose levels (p < 0.05) starting from the 7th day of treatment. Besides, the computational study and PASS analysis endorsed the current in vivo findings that the both isolated compounds exerted higher binding affinities to human pancreatic α-amylase and aldose reductase than the conventional drugs. The in silico ADMET analysis revealed that the both isolated compounds have a favorable pharmacokinetic and safety profile suitable for human consumption.ConclusionAccording to the current outcomes obtained from in vivo and in silico techniques, the leaf extract of L. glutinosa could be a natural remedy for treating diabetes, and the isolated phytoconstituents could be applied against various illnesses, mainly hyperglycemia. However, more investigations are required for extensive phytochemical isolation and pharmacological activities of these phytoconstituents against broader targets with exact mechanisms of action.

Molecular interactions between polyphenols and porcine α-amylase: An inhibition study on starch granules probed by kinetic, spectroscopic, calorimetric and in silico techniques

Inhibition of α-amylase activity to limit the rise in postprandial glucose is one of the most notable effects of dietary plant (poly)phenols. The rate and extent of inhibition depend on many factors, including the structure of (poly)phenols and the substrate used for the inhibition study. While soluble/gelatinised starch is widely used as a substrate for studying inhibition mechanisms, the formation of (poly)phenol-amylose complexes can reduce susceptibility to α-amylase catalysis. Therefore, the extent of inhibition may not truly represent the inhibition of α-amylase by (poly)phenols. To elucidate mechanisms of interactions between a (poly)phenol and the enzyme, this study compared the inhibition of porcine pancreatic α-amylase (PPA) by three differently structured (poly)phenols: p-coumaric acid, quercetin, and cyanidin-3-glucoside, using solid maize starch as a substrate, that limits the formation of starch-(poly)phenol complexes due to the compact structure of starch granules. The inhibition kinetics were investigated and supported by complementary techniques: in silico analysis (molecular docking and molecular dynamic simulation), fluorescence quenching, circular dichroism and differential scanning calorimetry. Quercetin exhibited the strongest inhibition, followed by cyanidin-3-glucoside and p-coumaric acid, with apparent modes of mixed, mixed, and competitive inhibition, respectively. The specific binding of (poly)phenols to PPA involved hydrogen bonds and hydrophobic interactions, as indicated by in-silico studies. Multi-spectroscopic analysis of the PPA structure unveiled changes or peak shifts due to ligand binding, resulting in structural alterations. These findings were consistent with the kinetic data, emphasising the importance of the structural aspects of each individual (poly)phenol in relation to their interaction with PPA. The study articulated the in-depth mechanism of molecular interaction mechanism between (poly)phenols and enzymes and provided evidence that the structural alterations of enzymes are not a strong indicator of inhibition efficacy, but rather inhibition is due to the binding of (poly)phenols to the enzyme structure limiting the catalysis.

Comparative analysis of granular starch hydrolysis and multi-structural changes by diverse α-amylases sources: Insights from waxy rice starch

Three cultivars of waxy rice starch with different multi-scale structures were subjected to α-amylase hydrolysis to determine amylopectin fine structure, production of oligosaccharides, morphology, and crystallinity of the partially hydrolyzed starch granules. α-amylases hydrolyzed the amylopectin B2 chain during the initial stage of hydrolysis, suggesting that it is primarily located in the outer shell of the granules. For waxy rice starch with loose structure, α-amylases attacked the crystalline and amorphous regions simultaneously in the initial stage, while for starch granules with compact structure, the outer shell blocklet (crystalline structure) can be a hurdle for α-amylases to proceed to hydrolysis of the internal granule structure. The ability of α-amylases from porcine pancreatic α-amylases to attack the outer shell crystalline structure was lower than that of α-amylases from Bacillus amyloliquefaciens and Aspergillus oryzae. These results show that α-amylase source and rice cultivar combinations can be used to generate diverse structures in degraded waxy rice starch.

Phytochemical investigation of Mezoneuron benthamianum Baill, isolation, in vitro antioxidant, alpha-amylase inhibition, and in silico modelling studies

Mezoneuron benthamianum (Leguminosae-caesalpinioideae family), is widely used across West Africa for the treatment of bacterial, fungal, and inflammatory diseases. This study is aimed at investigating the antioxidant and antidiabetic activities of extracts and isolated compounds from Mezoneuron benthamianum leaf and root. The pulverized leaf (1 kg) was extracted by maceration with dichloromethane and methanol to give the dichloromethane (MBLD) and methanol (MBLM) extracts, while the root (2 kg) samples were extracted using dichloromethane and methanol (1:1) to give the dichloromethane-methanol extract (MBRDM) which was further partitioned to give the hexane (MBRH), ethyl acetate (MBRE) and methanol (MBRM) extracts respectively. The leaf methanol extract (MBLM) was fractionated using column chromatography (70–230 mesh size) which led to the isolation of compound 1. The extracts and isolated compounds were subjected to in-vitro antioxidant assay with 1,1-diphenyl-2-picrylhydrazyl (DPPH) and α-amylase inhibitory assay using porcine pancreatic α-amylase respectively. FT-IR spectroscopic analysis compound 1 showed strong peaks at 1678 and 1612 cm−1 suggesting the presence of a carbonyl and an aromatic group respectively. 1H NMR spectroscopic analysis of compound 1 showed two peaks at 3.80 (3H, s) and 7.04 ppm (2H, s) indicating methoxy and aromatic protons respectively. 13C NMR also confirmed the presence of the methoxy peak at 50.8 ppm, four aromatic peaks at 108.76, 120.19, 131.25, 145.14 ppm indicating a para-disubstituted benzene ring, and a carbonyl peak at 167.80 ppm, this led to the elucidation of compound 1 known as methyl gallate. The antioxidant activities of the extracts and compounds showed that MBLM (IC50 = 112.0 μg/ml) and MBRE (IC50 = 91.84 μg/ml) had the highest activity of the leaf and root extracts respectively while methyl gallate (IC50 = 91.84 μg/ml) had lower activity than gallic acid (IC50 = 27.4 μg/ml), ascorbic acid (IC50 = 43.94 μg/ml) and BHT (68.94 μg/ml). The α-amylase inhibitory activities showed that MBLD (IC50 = 27.4 μg/ml), MBRE (IC50 = 72.2 μg/ml), gallic acid (IC50 = 27.4 μg/ml) and methyl gallate (IC50 = 43.9 μg/ml) had higher activity than the standard drug acarbose (IC50 = 378.2 μg/ml). For the In silico study, methyl gallate was docked into the active site of the targeted diabetic proteins; human pancreatic alpha-amylase, pig pancreatic alpha-amylase, and tetrameric IIB-HSDI. The results showed that methyl gallate had good interactions with the proteins, with binding affinities of −4.8, −4.8 and −6.5 kcal/mol respectively. Furthermore, in silico pharmacokinetics and toxicology properties of methyl gallate using the AdmetSAR and SwissADME software showed that the compound has good pharmacokinetic properties and it is generally non-toixc. This research has revealed detailed chemical and biological studies on Mezoneuron benthamianum and its isolated compound as an antioxidant and antidiabetic.

The substitution sites of hydroxyl and galloyl groups determine the inhibitory activity of human pancreatic α-amylase in twelve tea polyphenol monomers

Tea polyphenols have been reported as potential α-amylase inhibitors. However, the quantitative structure–activity relationship (QSAR) between tea polyphenols and human pancreas α-amylase (HPA) is not well understood. Herein, the inhibitory effect of twelve tea polyphenol monomers on HPA was investigated in terms of inhibitory activity, as well as QSAR analysis and interaction mechanism. The results revealed that the HPA inhibitory activity of theaflavins (TFs), especially theaflavin-3′-gallate (TF-3′-G, IC50: 0.313 mg/mL), was much stronger than that of catechins (IC50: 18.387–458.932 mg/mL). The QSAR analysis demonstrated that the determinant for the inhibitory activity of HPA was not the number of hydroxyl and galloyl groups in tea polyphenol monomers, while the substitution sites of these groups potentially might play a more important role in modulating the inhibitory activity. The inhibition kinetics and molecular docking revealed that TF-3′-G as a mixed-type inhibitor had the lowest inhibition constant and bound to the active sites of HPA with the lowest binding energy (−7.74 kcal/mol). These findings could provide valuable insights into the structures-activity relationships between tea polyphenols and the HPA inhibitors.

Comprehensive analysis of bioactive compounds in Crocus sativus stamens extracts by HPLC-DAD: investigating antidiabetic activity via in vitro, in vivo, and molecular docking simulation.

Introduction: Medicinal herbs used in traditional diabetes treatment are a rich source of anti-diabetic compounds. Pancreatic α-amylase inhibitors offer an effective strategy to reduce postprandial hyperglycemic levels via control of starch degradation. In this context, our study for the first time investigates the effect of Crocus sativus stamens extracts on α-amylase inhibition. Material and methods: The hydromethanolic and hydroethanolic extracts were obtained by macerating the dried stamen powder with methanol/water or ethanol/water, respectively. The total phenolic content of the stamen extracts was assessed using the Folin-Ciocalteu reagent method, while the total flavonoid content was determined using the Aluminum Chloride method. Phytochemicals were further quantified and identified using HPLC-DAD. For evaluation of hypoglycemic activity, in vitro α-amylase enzyme inhibition was calculated. The results were confirmed in vivo using an oral starch tolerance test in both normal and diabetic rats. Results: Our findings demonstrated a higher level of polyphenols and flavonoids in the hydroethanolic extract. Important flavonoids found were kaempferol, rutin, and vanillic acid, while prominent carotenoids contained trans- and cis-crocins. The in vitro study showed that both hydromethanolic and hydroethanolic extracts had considerable inhibitory effects, with maximum inhibitions of approximately 83% and 89%, respectively. In vivo tests indicated that both extracts effectively lowered peak blood glucose and area under the curve in both normal and diabetic rats following oral starch treatment. The obtained results are also supported by a docking study. Conclusion: These findings imply that C. sativus stamens possess a distinctive capability to reduce postprandial blood glucose levels. This effect is likely mediated through the inhibition of α-amylase, presenting a novel dietary avenue for managing diabetes.

The particle sizes of milled wheat fractions affect the in vitro starch digestibility and quality parameters of wire-cut cookies made thereof.

Slow digestion of starch is linked to various health benefits. The impact of wheat particle size on in vitro starch digestibility and quality of wire-cut cookies was here evaluated by including four soft wheat fractions [i.e. flour (average diameter, 83 μm), fine farina (643 μm), coarse farina (999 μm) and bran (1036 μm)] in the recipe. The susceptibility of starch in these fractions to in vitro digestion decreased with increasing particle size, resulting in a 76% lower digestion rate for coarse farina than for flour as found with the single first-order kinetic model. Starch was protected from hydrolysis likely due to delayed diffusion of pancreatic α-amylase through the intact farina cell walls. When 20-65% starch in flour for the control cookie recipe was substituted with the same percentages in fine and coarse farina, the starch digestion rate decreased when substitution levels increased. A 62% lower digestion rate was found at 65% substitution with coarse farina. Cell wall intactness was largely preserved in the cookies and most of the starch appeared as ungelatinised granules. Further, the cookie spread ratio during baking was 48% and 33% higher and the cookies were 63% and 57% less hard than control cookies when made with 65% fine farina and 65% coarse farina, respectively. The relatively low specific surface area of large wheat particles resulted in low water absorption and less dense packing. In conclusion, encapsulation of starch by intact cell walls in coarse wheat fractions makes them promising ingredients when developing starchy food products for controlled energy release.

Characteristics of the Digestive Tract of Dogs and Cats.

As for other mammals, the digestive system of dogs (facultative carnivores) and cats (obligate carnivores) includes the mouth, teeth, tongue, pharynx, esophagus, stomach, small intestine, large intestine, and accessory digestive organs (salivary glands, pancreas, liver, and gallbladder). These carnivores have a relatively shorter digestive tract but longer canine teeth, a tighter digitation of molars, and a greater stomach volume than omnivorousmammals such as humans and pigs. Both dogs and cats have no detectable or a very low activity of salivary α-amylase but dogs, unlike cats, possess a relativelyhighactivity of pancreatic α-amylase. Thus, cats select low-starch foods but dogs can consume high-starch diets. In contrast tomany mammals, the vitamin B12 (cobalamin)-binding intrinsic factor for the digestion and absorption of vitamin B12 is produced in: (a) dogs primarily by pancreatic ductal cells and to a lesser extent the gastric mucosa; and (b) cats exclusively by the pancreatic tissue. Amino acids (glutamate, glutamine, and aspartate) are the main metabolic fuels in enterocytes of the foregut. The primary function of the small intestine is to digest and absorb dietary nutrients, and its secondary function is to regulate the entry of dietary nutrients into the blood circulation, separate the external from the internal milieu, and perform immune surveillance. The major function of the large intestine is to ferment undigested food (particularly fiber and protein) and to absorb water, short-chain fatty acids (serving as major metabolic fuels for epithelial cells of the large intestine), as well as vitamins. The fermentation products, water, sloughed cells, digestive secretions, and microbes form feces and then pass into the rectum for excretion via the anal canal. The microflora influences colonic absorption and cell metabolism, as well as feces quality. The digestive tract is essential for the health, survival, growth, and development of dogs and cats.

Characteristics of Nutrition and Metabolism in Dogs and Cats.

Domestic dogs and cats have evolved differentially in some aspects of nutrition, metabolism, chemical sensing, and feeding behavior. The dogs have adapted to omnivorous diets containing taurine-abundant meat and starch-rich plant ingredients. By contrast, domestic cats must consume animal-sourced foods for survival, growth, and development. Both dogs and cats synthesize vitamin Cand many amino acids (AAs, such as alanine, asparagine, aspartate, glutamate, glutamine, glycine, proline, and serine), but have a limited ability to form de novo arginine and vitamin D3. Compared with dogs, cats have greater endogenous nitrogen losses and higher dietary requirements for AAs (particularly arginine, taurine, and tyrosine), B-complex vitamins (niacin, thiamin, folate, and biotin), and choline; exhibit greater rates of gluconeogenesis; are less sensitive to AA imbalances and antagonism; are more capable of concentrating urine through renal reabsorption of water; and cannot tolerate high levels of dietary starch due to limited pancreatic α-amylase activity. In addition, dogs can form sufficient taurine from cysteine (formost breeds); arachidonic acid from linoleic acid; eicosapentaenoic acid and docosahexaenoic acid from α-linolenic acid; all-trans-retinol from β-carotene; and niacin from tryptophan. These synthetic pathways, however, are either absent or limited in all cats due to (a)no or low activities of key enzymes (including pyrroline-5-carboxylate synthase, cysteine dioxygenase, ∆6-desaturase, β-carotene dioxygenase, and quinolinate phosphoribosyltransferase)and (b) diversion of intermediates to other metabolic pathways. Dogs can thrive on one large meal daily, select high-fat over low-fat diets, and consume sweet substances. By contrast, cats eat more frequently during light and dark periods, select high-protein over low-protein diets, refuse dry food, enjoy a consistent diet, and cannot taste sweetness. This knowledge guides the feeding and care of dogs and cats, as well as the manufacturing of their foods. As abundant sources of essential nutrients, animal-derived foodstuffs play important roles in optimizing the growth, development, and health of the companion animals.

Exploration of Anti-Diabetic Potential of Rubus ellipticus smith through Molecular Docking, Molecular Dynamics Simulation, and MMPBSA Calculation

Diabetes is a chronic metabolic disorder affecting a majority of the population worldwide. Hyperglycemia leading to diabetes mellitus could be managed through the inhibition of human pancreatic α-amylase enzyme. Phytochemicals are frequently reported to possess anti-diabetic activity through inhibition of normal functioning of α-amylase. This study aims to find potential α-amylase inhibitors from Rubus ellipticus Smith with molecular-level understanding using different computational tools. From the molecular docking calculations, rubuside F and rubuside D possessed good binding affinity of -10.0 kcal/mol and -9.9 kcal/mol, respectively better than the reference drugs (acarbose, miglitol, voglibose and metformin). Both the compounds showed good geometrical stability from molecular dynamics simulation accessed in terms of RMSD, hydrogen bond count, SASA, Rg and RMSF. Binding free energy changes of -27.92±4.15 kcal/mol and -28.75±4.15 kcal/mol, respectively for the two ligands indicated sustained thermodynamic spontaneity present in the adducts. The two phytochemicals could be proposed as potential inhibitors of human pancreatic α-amylase for the treatment of diabetes. Further, in vitro and in vivo experiments are recommended for the verification of computational insights in the course of drug design and discovery process.

Chemical Analysis of the Antihyperglycemic, and Pancreatic α-Amylase, Lipase, and Intestinal α-Glucosidase Inhibitory Activities of Cannabis sativa L. Seed Extracts.

Cannabis is considered (Cannabis sativa L.) a sacred herb in many countries and is vastly employed in traditional medicine to remedy numerous diseases, such as diabetes. This research investigates the chemical composition of the aqueous extracts from Cannabis sativa L. seeds. Furthermore, the impact of these extracts on pancreatic α-amylase and lipase, and intestinal α-glucosidase enzymes is evaluated, as well as their antihyperglycemic effect. Analysis of the chemical composition of the aqueous extract was conducted using high-performance liquid chromatography with a photodiode array detector (HPLC-DAD). In contrast, the ethanol, hexanic, dichloromethane, and aqueous extract compositions have been established. Additionally, the inhibitory effects of ethanolic, dichloromethane, and aqueous extracts on pancreatic α-amylase and lipase, and intestinal α-glucosidase activities were evaluated in vitro and in vivo. The results of HPLC analysis indicate that the most abundant phenolic compound in the aqueous cannabis seed extract is 3-hydroxycinnamic acid, followed by 4-hydroxybenzoic acid and rutin acid. Moreover, administration of ethanolic and aqueous extracts at a dose of 150 mg/Kg significantly suppressed postprandial hyperglycemia compared to the control group; the ethanolic, dichloromethane, and aqueous extracts significantly inhibit pancreatic α-amylase and lipase, and intestinal α-glucosidase in vitro. The pancreatic α-amylase test exhibited an inhibition with IC50 values of 16.36 ± 1.24 µg/mL, 19.33 ± 1.40 µg/mL, 23.53 ± 1.70 µg/mL, and 17.06 ± 9.91 µg/mL for EAq, EDm, EET, and EHx, respectively. EET has the highest inhibitory capacity for intestinal α-glucosidase activity, with an IC50 of 32.23 ± 3.26 µg/mL. The extracts inhibit porcine pancreatic lipase activity, demonstrating their potential as lipase inhibitors. Specifically, at a concentration of 1 mg/mL, the highest inhibition rate (77%) was observed for EDm. To confirm these results, the inhibitory effect of these extracts on enzymes was tested in vivo. The oral intake of aqueous extract markedly reduced starch- and sucrose-induced hyperglycemia in healthy rats. Administration of the ethanolic extract at a specific dose of 150 mg/kg significantly reduced postprandial glycemia compared with the control group. It is, therefore, undeniable that cannabis extracts represent a promising option as a potentially effective treatment for type 2 diabetes.

Characterization and bioactivities of coffee husks extract encapsulated with polyvinylpyrrolidone

Coffee processing generates large amounts of residues of which a portion still has bioactive properties due to their richness in phenolic compounds. This study aimed to obtain a coffee husks extract (CHE) and to encapsulate it (ECHE) with polyvinylpyrrolidone using a one-step procedure of solid dispersion. The extraction and encapsulation yields were 9.1% and 92%, respectively. Thermal analyses revealed that the encapsulation increased the thermal stability of CHE and dynamic light scattering analyses showed a bimodal distribution of size with 81% of the ECHE particles measuring approximately 711 nm. Trigonelline and caffeine were the main alkaloids and quercetin the main phenolic compound in CHE, and the encapsulation tripled quercetin extraction. The total phenolics content and the antioxidant activity of ECHE, assayed with three different procedures, were higher than those of CHE. The antioxidant activity and the bioaccessibility of the phenolic compounds of ECHE were also higher than those of CHE following simulated gastrointestinal digestion (SGID). Both CHE and ECHE were not toxic against Alliumcepa cells and showed similar capacities for inhibiting the pancreatic α-amylase in vitro. After SGID, however, ECHE became a 1.9-times stronger inhibitor of the α-amylase activity in vitro (IC50 = 8.5 mg/mL) when compared to CHE. Kinetic analysis revealed a non-competitive mechanism of inhibition and in silico docking simulation suggests that quercetin could be contributing significantly to the inhibitory action of both ECHE and CHE. In addition, ECHE (400 mg/kg) was able to delay by 50% the increases of blood glucose in vivo after oral administration of starch to rats. This finding shows that ECHE may be a candidate ingredient in dietary supplements used as an adjuvant for the treatment of diabetes.

Molecular docking studies on α-amylase inhibitory peptides from milk of different farm animals

Milk-derived peptides have emerged as a popular mean to manage various lifestyle disorders such as diabetes. Fermentation is being explored as one of the faster and efficient way of producing peptides with antidiabetic potential. Therefore, in this study, an attempt was made to comparatively investigate the pancreatic α-amylase (PAA) inhibitory properties of peptides derived from milk of different farm animals through probiotic fermentation. Peptide's identification was carried out using liquid chromatography-quadrupole time-of-flight mass spectrometry and inhibition mechanisms were characterized by molecular docking. Results obtained showed a PAA-IC50 value (the amount of protein equivalent needed to inhibit 50% of enzymes) between 2.39 and 36.1 µg protein equivalent for different fermented samples. Overall, Pediococcus pentosaceus MF000957-derived fermented milk from all animals indicated higher PAA inhibition than other probiotic derived fermented milk (PAA-IC50 values of 6.01, 3.53, 15.6, and 10.8 µg protein equivalent for bovine, camel, goat, and sheep fermented milk). Further, molecular docking analysis indicated that camel milk-derived peptide IMEQQQTEDEQQDK and goat milk-derived peptide DQHQKAMKPWTQPK were the most potent PAA inhibitory peptides. Overall, the study concluded that fermentation derived peptides may prove useful in for managing diabetes via inhibition of carbohydrate digesting enzyme PAA.

UPLC-Q-TOF-MS profiling of Viola stocksii Boiss. and evaluation of aphrodisiac potential and risk factors associated with erectile dysfunction

Ethnopharmacological relevanceViola stocksii Boiss. locally known as makhni or makhanr booti, is an important medicinal food plant with multiple therapeutic applications, including erectile dysfunction (ED). It is mixed with butter and used for boosting energy and sexual health in the subcontinent. Aims of the studyThis study was designed to evaluate the chemical composition, aphrodisiac potential and effect of V. stocksii on the risk factors associated with ED. MethodologyThe hydroethanolic extract of V. stocksii (HEEVS) was prepared through the microwave-assisted extraction (MAE) technique. The chemical composition was evaluated using preliminary phytochemical screening and UPLC-Q-TOF-MS analysis. Metals and minerals analysis was performed by an atomic absorption spectrophotometer. The aphrodisiac activity of HEEVS was evaluated using an in vivo aphrodisiac model established in male albino rats and the effect on various sexual parameters such as mount, intromission, ejaculation frequencies and mount, intromission, ejaculation latencies, postejaculatory interval, penile reflexes and serum hormone concentration were analyzed. The effect of HEEVS on various risk factors associated with ED, including prostate cancer (PC), bacterial infections, diabetes and obesity, was evaluated using various in vitro assays. Moreover, four compounds were selected from the UPLC-Q-TOF-MS profile and evaluated for in silico computational analysis against phosphodiesterase-5 (PDE-5) for possible interaction. FindingsThe phytochemical screening revealed the presence of various secondary metabolites in HEEVS, while 58 compounds were tentatively identified in the UPLC-Q-TOF-MS analysis. Various important minerals and metals such as zinc, calcium, cadmium and magnesium were detected in the atomic absorption spectrometry analysis. The in vivo aphrodisiac evaluation showed a significant (p < 0.05) increase in the mount, intromission and ejaculation frequencies and a decrease in the mount, intromission latencies and post-ejaculatory intervals at a dose of 300 mg/kg. A marked (p < 0.05) increase was observed in the concentration of serum testosterone and luteinizing hormones in HEEVS treated animals with a significant increase in total penile reflexes. The extract displayed significant anti-prostate cancer activity and a potential antibacterial spectrum against E. coli and S. aureus, with MIC50 values of 215.72 μg/mL and 139.05 μg/mL, respectively. Similarly, HEEVS was found active towards pancreatic lipase (67.34 ± 1.03%), α-glucosidase (3.87 ± 0.54 mmol ACAE/g d.w.) and α-amylase (6.98 ± 1.63 mmol ACAE/g d.w.). The in silico docking study presented a potential interaction between the selected compounds and residues of the active site of PDE-5. ConclusionThis report highlights the aphrodisiac potential of V. stocksii and provides experimental support for its traditional use in ED with an attenuative effect on the risk factors associated with ED. Moreover, the chemical composition displayed the presence of functional phytoconstituents and minerals in HEEVS and paves the way for the isolation of compounds with potent aphrodisiac activity.

In Silico and In Vitro Analyses to Repurpose Quercetin as a Human Pancreatic α-Amylase Inhibitor.

Human pancreatic α-amylase (HPA), situated at the apex of the starch digestion hierarchy, is an attractive therapeutic approach to precisely regulate blood glucose levels, thereby efficiently managing diabetes. Polyphenols offer a natural and multifaceted approach to moderate postprandial sugar spikes, with their slight modulation in carbohydrate digestion and potential secondary benefits, such as antioxidant and anti-inflammatory effects. Taking into consideration the unfavorable side effects of currently available commercial medications, we aimed to study a library of polyphenols attributed to their remarkable antidiabetic properties and screened the most potent HPA inhibitor via a comprehensive in silico study encompassing molecular docking, molecular mechanics with generalized Born and surface area solvation (MM/GBSA) calculation, molecular dynamics (MD) simulation, density functional theory (DFT) study, and pharmacokinetic properties followed by an in vitro assay. Significant hydrogen bonding with the catalytic triad residues of HPA, prominent MM/GBSA binding energy of -27.03 kcal/mol, and the stable nature of the protein-ligand complex with regard to 100 ns MD simulation screened quercetin as the best HPA inhibitor. Additionally, quercetin showed strong reactivity in the substrate-binding pocket of HPA and exhibited favorable pharmacokinetic properties with a considerable inhibitory concentration (IC50) of 57.37 ± 0.9 μg/mL against α-amylase. This study holds prospects for HPA inhibition and suggests quercetin as an approach to therapy for diabetes; however, it is imperative to conduct further research.

Eucalyptus camaldulensis Dehnh Leaf Essential Oil from Palestine Exhibits Antimicrobial and Antioxidant Activity but No Effect on Porcine Pancreatic Lipase and α-Amylase.

Eucalyptus camaldulensis Dehnh is a tree species that is commonly used for various purposes, including forestry, agroforestry, and conservation. The present investigation was designed to determine the composition of E. camaldulensis leaves essential oil and estimate its free radicals, porcine pancreatic lipase, α-amylase inhibitory, and antimicrobial properties in vitro. The chemical constituents were analyzed using the gas chromatography-mass spectrometry (GC-MS) technique. DPPH (2,2-diphenyl-1-picrylhydrazyl), p-nitrophenyl butyrate, and 3,5-dinitro salicylic acid (DNSA) methods were employed to estimate the antioxidant, antiobesity, and antidiabetic effects of the essential oil. The microdilution assay was employed to assess the antimicrobial efficacy of the substance against a total of seven distinct microbial species. The GC-MS results revealed that E. camaldulensis essential oil contains 52 components that makeup 100% of the entire oil. The main chemical constituents in E. camaldulensis essential oil are p-cymene (38.64%), followed by aromadendrene (29.65%), and 1,8-cineol (6.45%), with monocyclic monoterpene being the most abundant phytochemical group, followed by the sesquiterpene hydrocarbon group, representing 44.27 and 31.46%, respectively. The essential oil showed a weak antioxidant effect and had no antilipase or antiamylase effects. At the same time, the oil showed a strong antimicrobial effect against methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus, and Proteus vulgaris, which was even more potent than the positive controls, ciprofloxacin and ampicillin, which had MIC doses of 0.2 ± 0.01, 0.2 ± 0.01, and 6.25 ± 0.1 µg/mL, respectively. It also has a strong anti-Candida albicans effect with a MIC of 0.2 ± 0.01 µg/mL. In light of these findings, in vivo studies should be conducted to determine the efficiency of the E. camaldulensis essential oil in treating microbial infections.

327 A Novel, in Vivo Model to Increase Endogenous Pancreatic and Small Intestinal Carbohydrase Activity to Evaluate Limitations of Small Intestinal Starch Digestion in Cattle

Abstract Consumption of high-grain diets by cattle can result in large quantities of starch that flow to the small intestine for potential enzymatic digestion. However, small intestinal starch digestion is potentially limited because of insufficient activity of pancreatic and/or small intestinal carbohydrases. Studies suggest regulation of carbohydrase activity is complex in cattle and perhaps uncoordinated in response to luminal carbohydrate flow. The objective of this experiment was to use postruminal casein infusion and exogenous glucagon-like peptide 2 (GLP-2) administration, known stimulators of pancreatic and small intestinal function, to evaluate their effects on pancreatic and small intestinal carbohydrase activities. Twenty-four Holstein steers [250 ± 23 kg body weight (BW)] were used in a randomized complete block design with a 2 × 2 factorial arrangement of treatments. Steers were fed an alfalfa cube-based diet to limit dietary starch intake. Steers received a continuous abomasal infusion of 4 g/kg of BW of raw corn starch combined with either 0 or 1.33 g/kg of BW of casein for 7 d. Steers received subcutaneous injections in two portions daily of excipient (0.5% bovine serum albumin) or 100 µg/kg of BW GLP-2. This resulted in four treatments: control, casein, GLP-2, and casein + GLP-2. At the end of the 7-d treatment period, steers were slaughtered for pancreatic and small intestinal tissue collection. Data were analyzed using the GLM procedure of SAS. Postruminal casein infusion increased (P ≤ 0.03) pancreatic mass by 12.6%, total pancreatic α-amylase activity by 50%, and postruminal starch disappearance from 96.7% to 99.3%. Exogenous GLP-2 increased (P &amp;lt; 0.01) total small intestinal mass and small intestinal mucosal mass by 1.2 kg and 896 g, respectively. Relative to control, GLP-2 and casein + GLP-2 treatments increased (P = 0.04) total small intestinal α-glucosidase activity (sum of maltase, isomaltase, glucoamylase) by 83.5%. Total small intestinal maltase, isomaltase, and glucoamylase activity was 90%, 100%, and 66.7% greater for GLP-2 and casein + GLP-2 steers compared with control. The use of postruminal casein infusion and exogenous GLP-2 administration resulted in four distinct carbohydrase activity phenotypes. Relative to control, casein increased pancreatic α-amylase activity, GLP-2 increased small intestinal α-glucosidase activity, and the combination of casein and GLP-2 increased both pancreatic α-amylase activity and small intestinal α-glucosidase activity. This approach provides a novel in vivo animal model to selectively increase endogenous carbohydrase activity to overcome complications of coordinating carbohydrase activity with luminal nutrient flows. This model could be useful to understand physiological mechanisms that might improve small intestinal starch assimilation and efficiency of cattle consuming high-grain diets.

Antioxidant and antidiabetic activity and phytoconstituents of lichen extracts with temperate and polar distribution.

The objective of this research was to characterize the chemical composition of ethanolic extracts of the lichen species Placopsis contortuplicata, Ochrolechia frigida, and Umbilicaria antarctica, their antioxidant activity, and enzymatic inhibition through in vitro and molecular docking analysis. In total phenol content, FRAP, ORAC, and DPPH assays, the extracts showed significant antioxidant activity, and in in vitro assays for the inhibition of pancreatic lipase, α-glucosidase, and α-amylase enzymes, together with in silico studies for the prediction of pharmacokinetic properties, toxicity risks, and intermolecular interactions of compounds, the extracts evidenced inhibitory potential. A total of 13 compounds were identified by UHPLC-ESI-QTOF-MS in P. contortuplicata, 18 compounds in O. frigida, and 12 compounds in U. antarctica. This study contributes to the knowledge of the pool of bioactive compounds present in lichens of temperate and polar distribution and biological characteristics that increase interest in the discovery of natural products that offer alternatives for treatment studies of diseases related to oxidative stress and metabolic syndrome.