Α-glucosidase Activity Research Articles

Investigation on the inhibition mechanism and binding behavior of cryptolepine to α-glucosidase and its hypoglycemic activity by multi-spectroscopic method

Cryptolepine, one important active ingredient of Cryptolepis sanguinolenta (Lour), exhibits various beneficial pharmacological activities. But its anti-α-glucosidase and hypoglycemic activities are still not cleared. Thence, in this study, we investigated its inhibitory effects on α-glucosidase by a multi-spectroscopic method and in vivo hypoglycemic activity by the oral glucose tolerance test (OGTT). The results showed that cryptolepine is a reversible mixed-type α-glucosidase inhibitor with IC50 value of 0.44 ± 0.05 mM, ∼ 2-fold stronger than positive control acarbose (IC50: 0.72 ± 0.02 mM). Fluorescence quenching confirmed cryptolepine could quench the endogenous fluorescence of α-glucosidase in a static process. Fluorescence quenching, synchronous fluorescence, CD spectra, and 3D fluorescence results showed that the binding of cryptolepine with α-glucosidase caused chromophore microenvironment and conformation changes of α-glucosidase, consequently inhibiting its catalytic activity. Molecular docking revealed the detailed binding interactions between cryptolepine and α-glucosidase. Furthermore, oral administration of cryptolepine could improve the glucose tolerance in mice to reduce the postprandial hyperglycemia. These findings provide a solid foundation for understanding the inhibitory effects on α-glucosidase and hypoglycemic activity of cryptolepine.

Euclea natalensis Suppresses Postprandial Hyperglycemia in Rats via the Inhibition of α-Glucosidase: In vitro, in vivo, and Molecular Docking Studies

Background:: Postprandial hyperglycemia is a key factor in type 2 diabetes, and its management is critical in alleviating the deleterious consequences of diabetes and its associated micro and macrovascular complications. Objective:: The current study aims to determine the effect of Euclea natalensis leaf extracts on α- glucosidase inhibition in vitro and postprandial hyperglycemia in vivo in rats. Methods:: Sequentially extracted leaf extracts of Euclea natalensis were evaluated for their inhibitory effects on α-glucosidase in vitro and the suppression of postprandial hyperglycemia in normoglycemic rats. The extracts were fingerprinted using a Fourier-transform infrared spectrophotometer (FTIR), and the bioactive compounds were evaluated by molecular docking for their interaction with α-glucosidase. Results:: FTIR fingerprinting of the extracts showed that they contain functional groups of important bioactive phytochemicals. The extracts inhibited α-glucosidase in vitro, with the methanol extract (1 mg/mL) showing the highest inhibitory effect of 93.52 ± 1.50% compared to 69.62% ± 1.45 of the standard drug acarbose (0.05 mg/mL). The extracts also reduced postprandial hyperglycemia in rats in a sucrose tolerance test, where the hexane and methanol extracts performed similarly to Acarbose. Molecular docking studies showed that 20(29)-lupene-3β- isoferulate 3 is the most potent α-glucosidase inhibitor with the lowest binding energy of -10.79 kcal/mol, 2 hydrogen bonds with residues ASP1526 and ASP1157, and numerous Van der Waal interactions with amino acids in the binding pocket of α-glucosidase. Conclusion:: Euclea natalensis leaf extracts were found to suppress postprandial hyperglycemia by inhibiting α-glucosidase activity; thus, it has a promising potential for use as an antidiabetic agent.

The potentiality of isoflavones from Derris robusta (DC.) Benth. against α-glucosidase.

The four recently described isoflavones, derrisrobustones A-D, and eight known isoflavones extracted from Derris robusta (DC.) Benth. (Leguminosae) were identified as potential isoflavones for α-glucosidase inhibitory activity. However, the inhibitory ability of each isoflavone was quite different and the structural and dynamical properties of the isoflavones in the binding with α-glucosidase have not been studied. In this study, the molecular dynamics (MD) simulation and the molecular mechanics generalized Born surface area (MM/GBSA) methods were applied to gain insight into isoflavones bound with the α-glucosidase active site. The results found that the isoflavones with a hydroxy substituent could be stabilized in the α-glucosidase active site with low values of the binding free energy, especially derrisrobustone D and derrubone. The isoflavones, except for derrubone, were bound with α-glucosidase by means of electrostatic force effectively.

Characterization and discrimination of volatile organic compounds and α-glucosidase inhibitory activity of soybeans (Glycine max L.) during solid-state fermentation with Eurotium cristatum YL-1

In this study, the influence of solid-state fermentation (SSF) using probiotic Eurotium cristatum on the change of volatile organic compounds (VOCs) and α-glucosidase inhibition activity of soybeans was investigated. A total of 46 VOCs were characterized via headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS), the majority of which were aldehydes (17), alcohols (10), and ketones (7). SSF by E. cristatum drastically affected the flavor characteristics of soybeans, and the levels of unpleasant beany flavor components, such as hexanal-D, 1-octen-3-ol, 1-hexanol-D, 1-hexanol-M, heptanal-M, 1-pentanol, heptanal-D, and 2-pentyl furan were all substantially decreased by 50% after 15 days of SSF, while volatiles with floral, caramel, and desirable flavors such as pentanal-D, methylpropanal, 2-propanol, and propyl acetate drastically (p < 0.05) increased by 1.1-, 19.2-, 3.6-, and 2.6-fold, respectively. Key aroma-active compounds analysis revealed that 18 VOCs (ROAV, relative odor activity value ≥ 1) play a great role in shaping the flavor characteristics of the soybean samples. After 15 days of SSF, the ROAV values of methylpropanal, 2-propanol, and propyl acetate drastically (p < 0.05) increased to 8.48, 63.88, and 11.29, respectively, which greatly contributed to the desirable flavor characteristics of fermented soybeans. Furthermore, E. cristatum greatly improved the α-glucosidase inhibitory activity of soybean by 22.4% after 15 days fermentation, which was closely correlated with the accumulated phenolic compounds during SSF. Molecular docking showed that genistein and daidzein have high binding affinity for α-glucosidase active sites, primarily driven by hydrogen bonds and hydrophobic interactions. These results demonstrated that soybeans fermented with E. cristatum substantially improved the flavor characteristics and α-glucosidase inhibitory effect, and were greatly helpful to promote the application of soybeans in food products.

Phytochemical composition, antioxidant, antibacterial, and enzyme inhibitory activities of organic extracts from flower buds of Cleistocalyx operculatus (Roxb.) Merr. et Perry.

Cleistocalyx operculatus flower buds have been widely used in traditional medicine because of their rich content of bioactive constituents. In this study, we obtained seven solvent extracts from the flower buds and evaluated their total phenolic (TPC), flavonoid (TFC), tannin (TTC), triterpenoid saponin (TSC), and alkaloid (TAC) contents. We assessed antioxidant activities using the DPPH assay and also looked at antimicrobial and enzyme inhibitory effects. The water extract possessed the highest TPC (328.9 mg GAE/g extract), followed by ethanol, methanol, and hexane extracts (85.4-101.5 mg GAE/g extract). Chloroform, butanol, ethyl acetate, and ethanol extracts had high TSCs (245.4-287.2 mg OAE/g extract). The hexane extract was richest in TTC and TFC (32.7 mg CE/g extract and 81.1 mg QE/g extract, respectively). Ethanol and methanol extracts exhibited the strongest antioxidant activities (IC50 values of 25.2 and 30.3 μg/ml, respectively), followed by the water extract (IC50 of 40.2 μg/ml). The hexane extract displayed the most growth-inhibitory activity against Helicobacter pylori ATCC51932 and ATCC43504 strains and Salmonella enterica serovar Typhimurium ATCC13311 (MIC values of 0.06, 0.13, and 0.4 mg/ml, respectively). Moreover, the hexane extract revealed the strongest inhibition of H. pylori urease activity (IC50 of 4.51 μg/ml), whereas the water and methanol extracts had potent inhibitory effects on α-glucosidase activity (IC50 values of 9.9 and 15.1 μg/ml, respectively). These flower bud extracts could be used for health protection, especially in preventing bacterial infections and inhibiting enzymes associated with various human diseases. Further investigation into the application of C. operculatus flower buds in the food and pharmaceutical industries is necessary.

Investigation of functional, antioxidant, anti-inflammatory, and antidiabetic properties of legume seed protein hydrolysates

Plant-derived hydrolysates are emerging as promising agents in the management of diverse ailments due to their ensuing functional and bioactive properties. This study investigated the functional, antioxidant, anti-inflammatory, and antidiabetic properties of hydrolysates from Erythrina senegalensis and Vigna subtenarrea seeds. Crude proteins were isolated via alkaline solubilization, followed by acid precipitation to the isoelectric point. Respective protein isolates were hydrolyzed using trypsin and pepsin at an enzyme-substrate ratio of 1:8 (v/v) for 1–9 h. Pepsin hydrolysates after 9 h elicited the highest solubilities of 95.54 % and 94.24 % at pH 13, while, pepsin and trypsin hydrolysates of E. senegalensis digested for 1 and 9 h displayed the highest 1,1-diphenyl-2-picrylhydrazyl radical-scavenging (10-IC50 = 2.959 mg/mL) and total antioxidant capacity (7.243 mgAAE/g), respectively. Correspondingly, pepsin and trypsin hydrolysates of E. senegalensis hydrolyzed for 5 h demonstrated the most potent anti-inflammatory activities by cogently inhibiting xanthine oxidase and lipoxygenase activities with IC50 of 0.161 ± 0.111 and 0.018 ± 0.011 mg/mL, respectively. Trypsin hydrolysates of V. subterranea hydrolyzed for 5 h potently inhibited the activities of α-amylase and α-glucosidase with respective IC50 of 0.297 ± 0.060 and 0.314 ± 0.064 mg/mL. Overall, pepsin and trypsin hydrolysates of E. senegalensis demonstrated pronounced functional bioactivities relative to V. subterranea hydrolysates. This study concludes that both seeds could serve as unique matrices of potential functional bioactive peptides with prospects for managing diabetes.

N-Adamantanyl-2-(2-(phenyl)hydrazone)-3-oxobutanamides endowed with dual inhibitors of urease and α-glucosidase: Design, synthesis, and computational studies

The conventional approach of drug development, which focused on inhibiting a single target, has been superseded by a more advanced strategy known as multi-target design. In this study, we describe the synthesis of new N-adamantyl-2-(2-(phenyl)hydrazone)-3-oxobutanamide (6a-k). These compounds were designed with the intention of serving as prospective drug like candidates that can target both alpha glucosidase and urease enzymes. For this purpose, both in-vitro and in-silico investigations were performed after synthesis and characterization. The density functional theory calculations were employed to calculate optimized geometries, global reactivity descriptors and frontier molecular orbital (FMO) analysis. All compounds were found reactive and compounds 6b, 6c, 6d and 6e were found the most stable. The synthesized compounds were also tested for their ability to inhibit the enzyme activities of urease and α-glucosidase. The compound 6c exhibited strong inhibition of urease enzyme, with IC50 value of 13.10 ± 0.55 µM, in comparison to the IC50 value of the standard inhibitor thiourea i.e., 16.4 ± 1.02 µM. In addition to this, compounds 6d and 6e demonstrated a significant α-glucosidase inhibition with IC50 values of 17.16 ± 0.91 µM but found less potent as compared to the standard inhibitor Acarbose, i.e. 9.80 ± 0.20 μM. The structure–activity relationship (SAR) was established and the in-vitro results were further supported by the molecular docking investigations and molecular dynamic simulation studies. The in-vitro and in-silico results demonstrated a strong correlation in assessing the drug-like characteristics of all synthesized compounds (6a-k). The in silico investigation confirmed the findings in the search for inhibitors against the listed enzymes by elucidating the binding relationship between most of the active compounds and the active site of urease and α-glucosidase.

In vitro inhibitory effect of five natural sweeteners on α-glucosidase and α-amylase.

A promising and efficacious approach to manage diabetes is inhibiting α-glucosidase and α-amylase activity. Therefore, the inhibitory activities of five natural sweeteners (mogrosides (Mog), stevioside (Ste), glycyrrhizinic acid (GA), crude trilobatin (CT), and crude rubusoside (CR)) against α-glucosidase and α-amylase and their interactions were evaluated in vitro using enzyme kinetics, fluorescence spectroscopy, Fourier infrared spectroscopy, and molecular docking. The inhibitor sequence was CT > GA > Ste, as GA competitively inhibited α-glycosidase activity while CT and Ste exhibited mixed inhibitory effects. Compared to a positive control acarbose, the inhibitory activity of CT was higher. For α-amylase, the mixed inhibitors CT, CR, and Mog and the competitive inhibitor Ste effectively inhibited the enzyme, with the following order: CT > CR > Ste > Mog; nevertheless, the inhibitors were slightly inferior to acarbose. Three-dimensional fluorescence spectra depicted that GA, CT, and CR bound to the hydrophobic cavity of α-glucosidase or α-amylase and changed the polarity of the hydrophobic amino acid-based microenvironment and structure of the polypeptide chain backbone. Infrared spectroscopy revealed that GA, CT, and CR could disrupt the secondary structure of α-glucosidase or α-amylase, which decreased enzyme activity. GA, trilobatin and rubusoside bound to amino acid residues through hydrogen bonds and hydrophobic interactions, changing the conformation of enzyme molecules to decrease the enzymatic activity. Thus, CT, CR and GA exhibit promising inhibitory effects against α-glucosidase and α-amylase.

In vitro and in silico studies of alpha glucosidase inhibition and antifungal activity of coffea canephora husk.

The coffea canephora husk, a protected agricultural crop, is abundant in Vietnam. Examining the effects of C. canephora husk compounds on α-glucosidase and antifungal drug activity was the primary objective of this research. A cholestane-type steroid, coffeacanol A (1), was extracted from the ethyl acetate extract. Three cholestane-type derivatives (2-4) and three additional known compounds (5-7) were separated, and we used a variety of chromatographic techniques to identify a total of six substances. We used NMR to determine the chemical structures of these substances. Extensive HR-MS-ESI analysis and NMR experimental data were used to confirm the structure of the novel metabolite (1). The cholestane-type steroid was initially discovered in the Coffea canephora husk, marking the first instance in the coffee plant family to reveal chemical structures (1-7). The inhibition of α-glucosidase was found to be significantly higher in all compounds tested, with the exception of compounds (2) and (5). In vitro, the positive control showed the lowest inhibition, and the range of IC50 values was calculated to be 27.4 to 96.5 μM, which is lower than the IC50 value of 214.50 μM for the acarbose control. With an IC50 value of 27.4 μM, compound (7) showed the greatest capacity to inhibit α-glucosidase among the test compounds. The 3TOP and 2VF5 enzyme crystal structures were used for in silico docking investigations and validations of compounds (1-7). In silico calculations to explain how compound (7) shows high activity in vitro via the enzyme inhibition mechanism by residual amino acids, like Gly 1102 (B chain) and Glu 1095 (B chain), and their relative interaction with compounds (7) and acarbose. Compound (7) exhibited the best antifungal activity against Candida albicans fungus among three fungi, namely Candida albicans, Trichophyton mentagrophytes, and Trichophyton rubrum, with a MIC value of 25 μM. Compound (7) and fluconazole combined to form similar interactions in the contact ligand model, including the functional group, capping group, and linker part, which interacted fully with the 2VF5 enzyme, leading to effective in vitro inhibition.

Fluorometric and colorimetric dual-mode sensing of α-glucosidase based on aggregation-induced emission enhancement of AuNCs.

Herein, a fluorometric and colorimetric dual-mode assay platform used for α-glucosidase (α-Glu) activity sensing based on aggregation-induced emission enhancement (AIEE) of AuNCs was developed for the first time. The quantum yield (QY) and fluorescence lifetime of AuNCs were successfully ameliorated by Ce3+-triggered AIEE (Ce@AuNCs). Subsequently, on the basis of the inner filter effect (IFE) and dynamic quenching effect (DQE) between 2,6-dichlorophenolindophenol (DCIP) and Ce@AuNCs as well as the reduction of DCIP by ascorbic acid (AA) generated from α-Glu-catalyzed hydrolysis of L-ascorbic acid-2-O-α-D-glucopyranosyl (AA2G), the marriage of fluorometric and colorimetric modes applied for α-Glu activity monitoring was achieved. Besides, the feasibility of this dual-mode sensing system was confirmed by the assays versus potential interfering substances and in real samples. In particular, this system was further applied to evaluate natural α-Glu inhibitors (AGIs) including luteolin, apigenin, and hesperidin. Overall, the multi-mode optical sensor newly designed here has the potential for the accurate discovery of natural anti-diabetes drugs and the therapy of diabetes.

Discovery of new triterpene glycosides from Dendrobium officinale with their α-glucosidase and α-amylase inhibitory activity.

In this study, seven new pentacyclic triterpene glycosides, named dendrocinaosides A-G (1-7), and six known ones (8-13) were isolated from the whole plants of Dendrobium officinale. Their structures were determined by analyses of HR-ESI-MS, 1D and 2D NMR spectra. Compounds 1-4, 8, and 9 potentially inhibited α-glucosidase and α-amylase activities with the IC50 values ranging from 31.3 ± 2.2 to 42.4 ± 2.5 μM for anti α-glucosidase and from 36.5 ± 1.8 to 56.4 ± 2.0 μM for anti α-amylase activities, respectively, which were lower than that of the positive control, acarbose, showing IC50 values of 47.1 ± 1.4 μM for anti α-glucosidase and 145.7 ± 2.2 μM for anti α-amylase.

Novel sulfonamide derivatives as multitarget antidiabetic agents: design, synthesis, and biological evaluation.

A series of new sulfonamide derivatives connected through an imine linker to five or seven membered heterocycles were designed and synthesized. All synthesized derivatives were characterized using a variety of spectroscopic methods, including IR, 1HNMR, and 13CNMR. In vitro α-glucosidase and α-amylase inhibition activities, as well as glucose uptake were assessed for each of the synthesized compounds. Four sulfonamide derivatives namely 3a, 3b, 3h and 6 showed excellent inhibitory potential against α-glucosidase with IC50 values of 19.39, 25.12, 25.57 and 22.02 μM, respectively. They were 1.05- to 1.39-fold more potent than acarbose. Sulfonamide derivatives 3g, 3i and 7 (EC50 values of 1.29, 21.38 and 19.03 μM, respectively) exhibited significant glucose uptake activity that were 1.62- to 27-fold more potent than berberine. Both α-glucosidase protein (PDB: 2QMJ) and α-amylase (PDB: 1XCW) complexed with acarbose were adopted for docking investigations for the most active synthesized compounds. The docked compounds were able to inhabit the same space as the acarviosin ring of acarbose. The docking of the most active compounds showed an analogous binding with the active site of α-glucosidase as acarbose. The superior activity of the synthesized compounds against α-glucosidase enzyme than α-amylase enzyme can be rationalized by the weak interaction with the α-amylase. The physiochemical parameters of all synthesized compounds were aligned with Lipinski's rule of five.

Latilactobacillus sakei QC9 alleviates hyperglycaemia in high-fat diet and streptozotocin-induced type 2 diabetes mellitus mice via the microbiota-gut-liver axis.

Probiotics have been considered a promising option for mitigating the progression of type 2 diabetes mellitus (T2DM). Here, Latilactobacillus sakei QC9 (L. sakei QC9) with a hypoglycemic effect was screened out from 30 food-derived strains through α-glucosidase and α-amylase activity inhibition tests in vitro and a 4-week in vivo preliminary animal experiment. To further understand its alleviating effect on long-term hyperglycaemia occurring in T2DM, we conducted an experiment that lasted for 8 weeks. The results showed that taking L. sakei QC9 can regulate glucose and lipid metabolism while improving the antioxidant capacity and alleviating chronic inflammation. In addition, our results demonstrated that L. sakei QC9 may mediate the microbiota-gut-liver axis by regulating the composition of intestinal flora (increasing the abundance of butyrate-producing bacteria) and increasing the content of short-chain fatty acids (especially butyrate), affecting the PI3K/Akt signalling pathway in the liver, thereby achieving the purpose of alleviating the development of T2DM. In summary, our work is the first to prove the long-term hypoglycemic effect of L. sakei in high-fat diet (HFD) and streptozotocin (STZ)-induced T2DM mice and supports the possibility of L. sakei QC9 being used as a new treatment for alleviating T2DM.

Inhibition of α-glucosidase activity and intestinal glucose transport to assess the in vivo anti-hyperglycemic potential of dodecyl-acylated phlorizin and polydatin derivatives.

A diet containing natural active compounds that can inhibit the hydrolytic activity of α-glucosidase on carbohydrates and intestinal glucose absorption is an effective means of controlling postprandial hyperglycemia. Phlorizin and polydatin as phenolic glycosides have a high affinity for the catalytic site of α-glucosidase, but exhibited unsatisfactory competitive inhibitory capacity, with an IC50 of 0.97 and >2 mM, respectively. However, dodecyl-acylated derivatives of phlorizin and polydatin exerted α-glucosidase inhibitory capacity, with an IC50 of 55.10 and 70.95 μM, respectively, which were greatly enhanced and much stronger than that of acarbose with an IC50 of 2.46 mM. The SPR assay suggested the high affinity of dodecyl phlorizin and dodecyl polydatin to α-glucosidase with equilibrium dissociation constant (KD) values of 12.0 and 7.9 μM, respectively. Both dodecyl phlorizin and dodecyl polydatin reduced the catalytic ability of α-glucosidase by reversible noncompetitive and uncompetitive mixed inhibition, which bind noncovalently to the allosteric site 2 through hydrogen bonds and hydrophobic interactions, thereby inducing the secondary structure unfolding and intrinsic fluorescence quenching of α-glucosidase. Confocal microscopy detection visually showed significant inhibitory effects on FITC-labeled glucose uptake in intestinal Caco-2 cells by phlorizin, polydatin, dodecyl phlorizin and dodecyl polydatin. In addition, based on the differentiated Caco-2 cell monolayer model, dodecyl phlorizin and dodecyl polydatin suppressed intestinal glucose transport more effectively than phlorizin and polydatin, suggesting that they were promising in vivo hypoglycemic active compounds.

Anti-diabetic properties of brewer's spent yeast peptides. In vitro, in silico and ex vivo study after simulated gastrointestinal digestion.

Brewer's spent yeast (BSY) hydrolysates are a source of antidiabetic peptides. Nevertheless, the impact of in vitro gastrointestinal digestion of BSY derived peptides on diabetes has not been assessed. In this study, two BSY hydrolysates were obtained (H1 and H2) using β-glucanase and alkaline protease, with either 1 h or 2 h hydrolysis time for H1 and H2, respectively. These hydrolysates were then subjected to simulated gastrointestinal digestion (SGID), obtaining dialysates D1 and D2, respectively. BSY hydrolysates inhibited the activity of α-glucosidase and dipeptidyl peptidase IV (DPP-IV) enzymes. Moreover, although D2 was inactive against these enzymes, D1 IC50 value was lower than those found for the hydrolysates. Interestingly, after electrophoretic separation, D1 mannose-linked peptides showed the highest α-glucosidase inhibitory activity, while non-glycosylated peptides had the highest DPP-IV inhibitory activity. Kinetic analyses showed a non-competitive mechanism in both cases. After peptide identification, GILFVGSGVSGGEEGAR and IINEPTAAAIAYGLDK showed the highest in silico anti-diabetic activities among mannose-linked and non-glycosylated peptides, respectively (AntiDMPpred score: 0.70 and 0.77). Molecular docking also indicated that these peptides act as non-competitive inhibitors. Finally, an ex vivo model of mouse jejunum organoids was used to study the effect of D1 on the expression of intestinal epithelial genes related to diabetes. The reduction of the expression of genes that codify lactase, sucrase-isomaltase and glucose transporter 2 was observed, as well as an increase in the expression of Gip (glucose-dependent insulinotropic peptide) and Glp1 (glucagon-like peptide 1). This is the first report to evaluate the anti-diabetic effect of BSY peptides in mouse jejunum organoids.

Effect of drainage on microbial transformation processes of soil organic carbon in two typical wetlands of China

Wetlands store one third of global soil organic carbon (SOC) and are strongly affected by artificial drainage. The impact of drainage-induced water-table decline on carbon cycling in different wetlands, particularly microbial transformation processes, remains unclear. To address this knowledge gap, we collected soil samples from two typical wetlands of China (a nutrient-poor bog located in Dajiuhu and a nutrient-rich fen in Hongyuan) and conducted an incubation experiment with the addition of 13C-labeled glucose to analyze the effects of short- and long-term drainage on SOC decomposition, extracellular enzyme activity, microbial carbon use efficiency (CUE), and microbial carbon accumulation efficiency (CAE). The results showed that both short- and long-term drainage significantly increased SOC decomposition rates in both wetlands (from 1.47 μg C·g-1·h-1 in submerged soils to 2.47 μg C·g-1·h-1 in drained soils), microbial biomass carbon derived from glucose (from 0.21 mg C·g-1 to 1.00 mg C·g-1) and CAE (from 0.29 to 0.73), but did not alter CUE (ranging from 0.34 to 0.86). Long-term drainage increased α-glucosidase activity in the Dajiuhu wetland and decreased β-glucosidase and phenol oxidase activities in the Hongyuan wetland. In conclusion, drainage enhanced the 'microbial carbon pump' and its efficiency in wetlands mainly via increasing microbial intracellular metabolism (including respiration), but also acce-lerated SOC decomposition.

Lacticaseibacillus casei- and Bifidobacterium breve-fermented red pitaya promotes beneficial microbial proliferation in the colon.

Red pitaya has been demonstrated to strongly inhibit α-glucosidase activity; however, the impact of red pitaya fermentation by probiotic bacteria on α-glucosidase inhibition remains unclear. In this study, six strains of lactic acid bacteria (Lactiplantibacillus plantarum, Lacticaseibacillus rhamnosus, Lactobacillus bulgaricus, Lacticaseibacillus casei, Lactobacillus acidophilus and Streptococcus thermophilus) and one strain of Bifidobacterium breve were utilized for the fermentation of red pitaya pulp. The α-glucosidase and α-amylase inhibition rates of red pitaya pulp were significantly greater after fermentation by Bifidobacterium breve and Lacticaseibacillus casei than by the other abovementioned strains. The LC group exhibited an α-glucosidase inhibition rate of 99%, with an α-amylase inhibition rate of 89.91%. In contrast, the BB group exhibited an α-glucosidase inhibition rate of 95.28%, accompanied by an α-amylase inhibition rate of 95.28%. Moreover, red pitaya pulp fermented with Bifidobacterium breve and Lacticaseibacillus casei produced a notable quantity of oligosaccharides, which was more than three times greater than that in the other groups. Furthermore, 16S rRNA high-throughput sequencing analysis was conducted to assess alterations in the composition of the gut microbiota. This revealed an increase in the abundance of Lactobacillus and Faecalibacterium in the pulp fermented by Bifidobacterium breve and Lacticaseibacillus casei, whereas the abundance of Sutterella decreased. Further analysis at the species level revealed that Bifidobacterium longum, Faecalibacterium prausnitzii, and Lactobacillus zeae were the dominant strains present during colonic fermentation. These results indicate a beneficial health trend associated with probiotic bacterial fermentation of red pitaya pulp, which is highly important for the development of functional products.

In vitro and functional investigation reveals the curative effect of thymoquinone from black cumin-loaded chitosan nanoparticles on streptozotocin induced paediatric diabetes

Diabetic ketoacidosis (DKA) is regarded to be a communal complication of both type 1 and type 2 diabetes mellitus in children and adolescents. Successful therapy of DKA in children requires prompt diagnosis, strict monitoring of medical indicators, and prompt action. Thymoquinone (Tq) from black cumin loaded chitosan nanoparticles (ChNPs) intend to assess an effective agent to overcome this problem. XRD, FTIR, SEM, and TEM were used in the physicochemical analysis. Enzymatic activity of α-amylase and α-glucosidase was used in in vitro tests of anti-diabetic efficacy. Protecting insulin against enzyme breakdown is a crucial part of the insulin delivery mechanism. In the STZ-induced diabetes RIN-5F cell line, the anti-apoptotic capability of Tq-ChNPs was demonstrated through the NF-κB mediated apoptotic pathway. The combination of thymoquinone and chitosan NPs demonstrated that a wide variety of incredibly effective substances to elevate their curative effects, thus contributing to the growth of clinical and pharmaceutical fields.

Inhibitory Activity of PTP1B and α-Glucosidase by Compounds from Whole Plants of Houttuynia cordata Thunb.

Inhibitory Activity of PTP1B and α-Glucosidase by Compounds from Whole Plants of Houttuynia cordata Thunb.

Phenolic Compounds, Free Radical Scavenging Activity and α-Glucosidase Inhibition Properties of Green, Oolong and Black Sacha Inchi Tea Extract

Sacha Inchi leaves may possess antioxidant function which is naturally rich in bioactive ingredients and has been widely processed into herbal teas that has many benefits to human health. According to the global data from the World Health Organization (WHO), there has been a rise in the frequency of diabetes mellitus (DM) among adults. Sacha Inchi tea was prepared using several methods, with green tea not fermented, oolong partially fermented, and black tea completely fermented. The phenolic compounds (total phenolic content (TPC), total flavonoid content (TFC), tannin), free radical scavenging activity (DPPH) and inhibition properties of α-Glucosidase on green, oolong and black Sacha Inchi tea extract were determined. The green Sacha Inchi tea extract displayed the highest TPC and TFC values among the oolong and black Sacha Inchi tea extracts at a concentration of 500µg/mL, with values of 2.10±0.01 µg GAE/mL and 3.23±0.20 µg QE/mL, respectively. Meanwhile, at a concentration of 500µg/mL, Sacha Inchi black tea extract demonstrated strong antioxidant activity by DPPH with radical scavenging activity (%) (89.4±0.45). Furthermore, at a concentration of 15.625 µg/mL, black, oolong, and green tea extracts exhibited stronger inhibitory effects on α-Glucosidase (95%, 95%, 92%, respectively) than acarbose (90%). Therefore, the processing steps involved in tea production impact the phenolic compounds, free radical scavenging activity, and the ability to inhibit α-Glucosidase in green, oolong, and black tea extracts.