Α-amylase Inhibitory Activity Research Articles

Comprehensive analysis of malabar tamarind fruit rind total extract: HPTLC fingerprinting, in-silico exploration of its metabolites for SARS-cov-2 omicron spike protein, antibacterial and antidiabetic potentials with in vitro evaluation of antidiabetic and antioxidant activities

Malabar tamarind tropical fruit, scientifically known as Garcinia gummi-gutta, is indigenous to Southeast Asia. In this work, the total methanolic extract of the Malabar fruit rind was examined by HPTLC fingerprinting, with quantitative evaluation of the total phenolics and flavonoids. Library of previously reported natural metabolites was utilized to demonstrate their affinity for specific target sites, they were evaluated against Omicron SARS-CoV-2 mainly it's Spike Protein, bacterial tyrosinase, and antidiabetic targets such α-glucosidase, pancreatic lipase and also α-amylase enzymes. The molecular docking revealed that the Guttiferone R possessed the highest binding affinity toward the Omicron Spike Protein with a stable binding mode, −8.67 kcal/mol binding energy and a 1.07 Å RMSD value compared to reference, Azithromycin, which has −8.90 kcal/mol binding affinity and a 1.20 Å RMSD value. On the other hand, the identified polyphenolic compounds; Vitexin, Prunin, Naringin, Hinokiflavone, Kaempherol-3-O-rutinoside, Gallic acid, Naringenin, and Catechin, showed remarkable antidiabetic activity by strong inhibitory activity against α-glucosidase and notable activity against α-amylase compared with acarbose as reference. According to antibacterial activity, the identified compounds showed low affinity with weak activity against screened bacterial strains. In-vitro evaluation of Tamarind antioxidant and antidiabetic potentials, it exhibited a free radical-scavenging potential with 71.75 % retardation and α-glucosidase, α-amylase and pancreatic lipase inhibitor activities with an IC50 of 391.3 ± 26.27, 95.03 ± 0.03 and 0.01043 ± 0.0004 μg/mL, respectively that emphasize the molecular docking study. The findings imply that Malabar tamarind fruit rind possess antioxidant, antidiabetic, antibacterial and antiviral activities.

Correction: Alpha-glucosidase and α-amylase inhibitory activity of Pistacia atlantica Desf. Gall extracts and identification of putative bioactives using a combined UPLC fingerprinting and molecular docking approach

Correction: Alpha-glucosidase and α-amylase inhibitory activity of Pistacia atlantica Desf. Gall extracts and identification of putative bioactives using a combined UPLC fingerprinting and molecular docking approach

Restraint of Starch-hydrolyzing Enzyme in the Management of Postprandial Blood Glucose Level: An Alternative Approach

Background: Diabetes is a multifaceted metabolic condition defined by postprandial hyperglycemia with perturbances in the majority of the metabolic systems in the human body. α-amylase is a key enzyme present in pancreatic juice and saliva that converts one of the common food sources i.e., starch molecules into absorbable molecules and raises plasma glucose levels. Reducing starch digestion by the inhibitors of starch hydrolyzing enzymes could be an intriguing strategy for improved postprandial hyperglycemia management. Objective: The present research work was undertaken to evaluate the inhibition potential of natural inhibitors of α-amylase from Trichosanthes dioica (pointed gourd) and Moringa oleifera (moringa leaves) extracts in vitro. Furthermore, in vivo cytotoxicity assessment was also conducted through brine shrimp lethality bioassay. Methods: Different organic solvents (namely acetone, ethanol, and methanol) were used to isolate plant extracts. DNS (3,5-dinitrosalicylic acid) was used to conduct the α-amylase inhibition assay. The safety of the natural inhibitors was determined by the most common technique i.e, brine shrimp lethality bioassay. Results: Among all the different organic solvent extracts, pointed gourd and its peel exhibited the highest α-amylase inhibition activity (64.03 ± 7.33–69.40 ± 9.38%) which is very close to standard α-amylase inhibitor acarbose (72.34 ± 4.23%) whereas moringa leaves showed moderate inhibition activities (59.10 ± 5.25–62.03 ± 1.77%). The cytotoxicity of pointed gourd and its peel was higher while moringa leaves demonstrated lower toxicity. Conclusion: Considering the inhibition rate and cytotoxicity, pointed gourd ethanol extract (Inhibition: 67.43 ± 11.80%; Cytotoxicity: 209.98 μg/mL) would be the best candidate for managing postprandial hyperglycemia.

Anti-diabetic, anti-bacterial and anti-oxidant potential of new biologically active thiazole-derivatives: Experimental and molecular docking studies

In this study, we synthesised and characterised a series of thiazole derivatives (compounds 3a–j) and assessed their potential for anti-diabetic, anti-bacterial and anti-oxidant activities. The anti-diabetic potential of the compounds was assessed by measuring their inhibition of key enzymes involved in blood glucose regulation. Compound 3i demonstrated the highest α-Amylase inhibition activity (IC50 value: 18.68 µg/mL), while compounds 3i and 3c exhibited significant α-Glucosidase inhibition (IC50 values: 20.25 and 22.63 µg/mL respectively), even surpassing the control drug, Acarbose (IC50 value: 33.77 µg/mL). Interestingly, most of the compounds displayed favourable dipeptidyl peptidase IV (DPP IV) inhibition and DPPH scavenging ability, with compound 3i showing the highest DPP IV inhibition ability (IC50 value: 23.81 µg/mL) and most robust anti-oxidant potential (IC50 value: 2.50 µg/mL). Additionally, anti-bacterial studies against Staphylococcus aureus and Escherichia coli revealed compounds 3i and 3c as effective inhibitors of bacterial growth. The MICs (4, 16, 16, and 32 µg/mL) and MBCs (4, 32, 32, and 16 µg/mL) respectively of the compounds supported their potential application in controlling and preventing bacterial growth. These results provide valuable insights into the multifunctional properties of the new thiazole derivatives and their potential in managing diabetes, combating bacterial infections, and serving as anti-oxidants.

Alpha-glucosidase and α-amylase inhibitory activity of Pistacia atlantica Desf. gall extracts and identification of putative bioactives using a combined UPLC fingerprinting and molecular docking approach

Alpha-glucosidase and α-amylase inhibitory activity of Pistacia atlantica Desf. gall extracts and identification of putative bioactives using a combined UPLC fingerprinting and molecular docking approach

Studying the Anti-microbial and Alpha Amylase Inhibition Activity of Cerium Oxide Nanoparticles for Biomedical Applications

Cerium oxide nanoparticles (CNP) have been produced using a wet chemical technique. The therapeutic capacities of cerium oxide nanoparticles are determined based on the analysis of their anti-diabetic and antibacterial activities. The study below demonstrated the antibacterial characteristics of cerium oxide nanoparticles (CNP) against several bacteria. Specifically, the inhibition zones observed for Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Enterococcus gergovae were 14.5mm, 11mm, 17mm, and 15mm, respectively. The results obtained indicate that CNP has the potential to address the urgent problem of hospital-acquired microbial infections, particularly those caused by antibiotic-resistant microorganisms. Additionally, the anti-diabetic property of CNP was evaluated and found to have a 66% alpha amylase inhibition, which suggests a significant reduction in glucose levels. Therefore, it has the potential to be utilized as an antidiabetic medication as well. The study has produced a compound with potent biological capabilities that can be enhanced through a synthesis technique and utilized in the pharmaceutical industry.

Integrative metabolomics and chemometrics depict the metabolic alterations of differently processed red kidney beans (Phaseolus vulgaris L.) and in relation to in-vitro anti-diabetic efficacy

Red kidney beans (RKB) serve as a powerhouse packed with a plethora of largely unexplored extraordinary chemical entities with potential significance. However, their nutraceutical applications as a functional hypoglycemic food still lag behind and warrant further investigation. With a scope to optimize chemical and biological traits of RKB, green modification approaches (processing methods) seem inevitable. Accordingly, the current study offered the first integrative workflow to scrutinize dynamic changes in chemical profiles of differently processed RKB and their potential entanglements on diabetes mitigation using Ultra Performance Liquid Chromatography-mass spectrometry (UPLC-MS/MS) coupled with chemometrics. Different physical and biological processing treatments namely germination, fermentation, cooking and dehulling were preliminarily implemented on RKB. Complementarily, the concomitant metabolite alterations among differently processed RKB were monitored and interpreted. Next, an in-vitro α-amylase and α-glycosidase inhibitory testing of the differently processed samples was conducted and integrated with orthogonal projection to latent structures (OPLS) analysis to pinpoint the possible efficacy compounds. A total of 72 compounds spanning fatty acids and their glycerides, flavonoids, phenolic acids, amino acids, dipeptides, phytosterols and betaxanthins were profiled. Given this analysis and compared with raw unprocessed samples, it was found that flavonoids experienced notable accumulation during germination while both fermentation and dehulling approaches sharply intensified the content of amino acids and dipeptides. Comparably, Fatty acids, phytosterols and betaxanthins were unevenly distributed among the comparable samples. Admittedly, OPLS-DA revealed an evident discrimination among the processed samples assuring their quite compositional discrepancies. In a more targeted approach, kaempferol-O-sophoroside, quercetin, carlinoside and betavulgarin emerged as focal discriminators of sprouted samples while citrulline, linoleic acid, linolenoyl-glycerol and stigmasterol were the determining metabolites in cooked samples. Our efficacy experimental findings emphasized that the different RKB samples exerted profound inhibitory actions against both α-amylase and α-glycosidase enzymes with the most promising observations in the case of sprouted and cooked samples. Coincidently, OPLS analysis revealed selective enhancement of possible efficacy constituents primarily citrulline, formononetin, gamabufotalin, kaempferol-O-sophoroside, carlinoside, oleic acid and ergosterol in sprouted and cooked samples rationalizing their noteworthy α-amylase and α-glucosidase inhibitory activities. Taken together, this integrated work provides insightful perspectives beyond the positive impact of different processing protocols on bioactives accumulation and pharmacological traits of RKB expanding their utilization as functional hypoglycemic food to rectify diabetes.

Synthesis of modified Schiff base appended 1,2,4-triazole hybrids scaffolds: elucidating the invitro and in silico α-amylase and α-glucosidase inhibitors potential.

The current study involves the synthesis of Schiff bases based on 1,2,4-triazoles skeleton and assessing their α-amylase and α-glucosidase profile. Furthermore, the precise structures of the synthesized derivatives were elucidated using various spectroscopic methods such as 1H-NMR, 13C-NMR and HREI-MS. Using glimepiride as the reference standard, the invitro α-glucosidase and α-amylase inhibitory activities of the synthesized compounds were evaluated in order to determine their potential anti-diabetic properties. All analogues showed varied range of inhibitory activity having IC50 values ranging from 17.09±0.72 to 45.34±0.03 μM (α-amylase) and 16.35±0.42 to 42.31±0.09 μM (α-glucosidase), respectively. Specifically, the compounds 1, 7 and 8 were found to be significantly active with IC50 values of 17.09±0.72, 19.73±0.42, and 23.01±0.04 μM (against α-amylase) and 16.35±0.42, 18.55±0.26, and 20.07±0.02 μM (against α-glucosidase) respectively. The obtained results were compared with the Glimepiride reference drug having IC50values of 13.02±0.11 μM (for α-glucosidase) and 15.04±0.02 μM (for α-amylase), respectively. The structure-activity relationship (SAR) studies were conducted based on differences in substituent patterns at varying position of aryl rings A and B may cause to alter the inhibitory activities of both α-amylase and α-glucosidase enzymes. Additionally, the molecular docking study was carried out to explore the binding interactions possessed by most active analogues with the active sites of targeted α-amylase and α-glucosidase enzymes.

The Volatile Composition and the Potential Health Benefits of Different Microalgae Strains.

The use of microalgae as a food ingredient has been gaining attention in recent years due to its nutritional benefits. The main goals of this study were to (i) assess the nutritional potential of Chlorella vulgaris, Tetraselmis chuii, Microchloropsis gaditana, and Phaeodactylum tricornutum; (ii) evaluate their bioactive properties (antioxidant activity, total phenolic content, and α-amylase inhibitory activity) and (iii) assess the main volatile compounds composition. The protein content was considerably high (32-44 mg/100 g dw) for all the microalgae strains. The DPPH scavenging potential range was 14-25 mg Trolox/100 g dw (highest for T. chuii) and the ferric reducing power ability range was 13-67 µmol Trolox/dw (higher for T. chuii). The total phenolic content range was 2-7 mg of gallic acid equivalents/g dw, for M. gaditana and T. chuii, respectively, which was mainly due to the presence of catechin (1-9 µg/g dw), epicatechin (3-29 µg/g dw), and vanillic acid (1-14 µg/g dw). The ɑ-amylase inhibitory potential range was 26-42%. C. vulgaris was richer in chlorophyll a (18 mg/g dw), whilst T. chuii was particularly rich in chlorophyll b (29 mg/g dw). P. tricornutum showed the highest carotenoid content (4 mg/g dw). Aldehydes and alkanes were the major compounds identified in M. gaditana, whereas alcohols and N-based compounds existed in higher amounts in P. tricornutum. T. chuii and C. vulgaris were enriched in ketones and alkenes. This study's novelty lies in its comprehensive and integrative analysis of the nutritional, bioactive, and volatile properties of four distinct microalgae strains. By providing detailed comparisons and highlighting potential applications in functional foods, it offers a unique contribution to the field of microalgae research and its practical application in the food industry. This multifaceted approach sets it apart from existing studies, offering new insights and opportunities for leveraging microalgae as valuable food ingredients.

Interaction between orange juice and < 1 kDa leaf peptides: effect on the antioxidant and antidiabetic related enzyme inhibitory activities

Designing a good vehicle for functional ingredients is the major focus of this study. Small molecular weight peptides (< 1 kDa) extracted from amaranth leaf protein (ALP), eggplant leaf protein (ELP) and fluted pumpkin leaf protein (FLP) were incorporated into freshly prepared orange juice at an effective and inhibitory concentrations of the peptides. The rate of degradation of ascorbic acid was more in the control juice (140.06 to 18.43 mg/mL) when compared with juice containing peptides at both storage conditions (140.08 to 32.32 mg/mL). However, the rate of ascorbic acid reduction during storage (refrigerated and ambient) was least in the juice containing peptide, isolated from ELP when compared with the juice samples that contained peptides isolated from ALP and FLP. After the eighth week of storage, juice that contained FLP peptide had greater amounts of residual total phenolic content (370.53 & 432.33 µg GAE/100 mL), juice that contained ALP peptide retained better ability to scavenge DPPH radicals (52.32 & 66.84%) while juice sample that contained ELP retained more metal chelating activities (44.82 and 51.03%). The results of antidiabetic property showed that juice containing peptide isolated from ALP contained greater amounts of α-amylase inhibitory activity (41.50 and 46.89%) while greater amounts of α-glucosidase inhibitory activities were retained in juice that contained peptide isolated from FLP. The results concluded that orange juice may be considered a veritable vehicle for functional ingredients for improved health.Graphical

Preclinical antidiabetic and antioxidant effects of Erythrophleum africanum (benth.) harms in streptozotocin-induced diabetic nephropathy.

This study investigated the antidiabetic effects of the methanolic extract of E.africanum (MEEA) stem bark on streptozotocin (STZ)-induced diabetic nephropathy (DN) in Wistar rats. The invitro enzyme (α-amylase) inhibitory activity of MEEA was measured using a standard procedure. Diabetic rats with fasting blood glucose above 250 mg/dL were considered diabetic and were divided intothe following groups: control (distilled water-treated), diabetic-control, diabetic metformin (100 mg/kg), diabetes + MEEA (150 mg/kg), and diabetes + MEEA (300 mg/kg) via oral gavage once daily for 14days. At the end of the experimental period, kidney tissues were collected for biochemical and histological analyses. Kidney apoptosis and marker gene expression were measured by real-time quantitative PCR. MEEA exhibited α-amylase inhibitory effects. MEEA significantly (p<0.05) reduced the STZ-induced increases in blood glucose, serum urea, serum creatinine, uric acid, alanine aminotransferase, alkaline phosphatase, and malondialdehyde and increased the STZ-induced decreases in superoxide dismutase, catalase, and reduced glutathione. In addition, MEEA protects against DN by significantly downregulating the mRNA expression of cyclic adenosine monophosphate (cAMP), protein kinase A (PKA), cAMP-response binding protein (CREB), and cFOS and upregulating B-cell lymphoma 2 (Bcl-2), suggesting that the nephroprotective ability of MEEA is due to the modulation of the cAMP/PKA/CREB/cFOS signaling pathway. Furthermore, MEEA treatment protected against histopathological alterations observed in diabetic rats. The data from this study suggest that MEEA modulates glucose homeostasis and inhibits redox imbalance in DN rats.

Augmentation of α-amylase and α-glucosidase inhibitory properties of Callerya speciosa root extracts: An exploration through simulated human gastrointestinal digestion

The present work represents the first effort to evaluate the effect of an in vitro simulated human digestion model on the α-amylase and α-glucosidase inhibitory activities of Callerya speciosa root extracts. Through bioguided fractionation, a series of fractions were obtained from hexane (CSH) and ethyl acetate (CSE) extracts. Initial screening identified active fractions (CSH2, CSH3, CSE2, CSE3, and CSE4) for further in vitro digestion evaluation. The results showed a decrease in antioxidant activity across all samples after digestion, while a simultaneous increase in α-amylase and α-glucosidase inhibitory activities was observed during the small intestinal phase. Notably, compared with the undigested fraction, CSE3 demonstrated a 1.7-fold increase in α-amylase inhibition (IC50 = 0.86 mg/mL). Moreover, the α-glucosidase inhibitory activities of CSH3, CSE3, and CSE4 were significantly greater after digestion, with IC50 values of 0.18, 0.05, and 0.02 mg/mL, respectively. Impressively, during the small intestinal phase, the α-glucosidase inhibitory activities of CSH3, CSE3, and CSE4 were substantially greater than those of acarbose by 13.2-, 47.6-, and 119.0-fold, respectively, and greater than those of palmitic acid by 1.7-, 6.0-, and 15.0-fold, respectively. GC-MS and LC-ESI-MS/MS analyses identified isoflavonoids, fatty acids, and triterpenoids as key bioactive compounds in these fractions. The present work provided foundational insights for the future exploration of C. speciosa root extracts for diabetes management.

Design and synthesis of novel thiazolidinone hybrid as α-amylase inhibitor, glucose uptake and antioxidant activity

A design and synthesis of novel series of substituted thiazolidinone has been synthesised from 2-amino-thiazole and pyrazole-2-aldehyde using DCC under mild condition. These compounds were first examined for α-amylase inhibition, glucose uptake activity and antioxidant activities. The α-amylase inhibition profile was found to be competitive for compound 3b. Including, compounds 3h exhibited significant glucose update activity with IC50 values of 10.21 μM. Additionally, the free-radical scavenging activity of 3a-n was assessed using the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay.

Exploring New Schiff Bases: Synthesis, Characterization, and Multifaceted Analysis for Biomedical Applications.

The current work aims to generate novel Schiff bases by reacting substituted aldehydes with amine derivatives catalyzed by a natural acid. The developed compounds underwent diverse physicochemical analyses including liquid chromatography-mass spectrometry, Fourier transform infrared spectroscopy, scanning electron microscopy, 1H- and 13C-nuclear magnetic resonance, and X-ray diffraction. Furthermore, differential thermogravimetric, thermogravimetric, and differential thermal analysis techniques were employed in a nitrogen-free environment to determine kinetic parameters. These data were then used in model-free isoconversional methods (e.g., Friedman, Kissinger-Akahira-Sunose, and Flynn-Wall-Ozawa). The Schiff bases were evaluated for their in vitro and in silico α-amylase inhibitory activity. Schiff base-2 displayed the highest inhibition compared with the reference drug acarbose. In comprehensive MTT assay cytotoxicity investigations, both Schiff bases showed strong anticancer capabilities against the human lung cancer cell line (A549). Moreover, this study demonstrated effectiveness of synthetic compounds in screening Caenorhabditis elegans for anti-Alzheimer's and stress resistance properties. The simplicity of its biology allowed precise evaluation of the effect of compounds on neuronal function and stress response. This research enhances drug discovery efforts for Alzheimer's and stress-related disorders, potentially improving patient outcomes.

High-throughput screening, “protein–metabolite” interaction, and hypoglycemic effect investigations of α-amylase inhibitors in teas using an affinity selection-mass spectrometry method

Tea is consumed worldwide and can reduce the risk of diabetes whereas the hypoglycemic compounds in tea remain unclear. Herein, the chemical compositions comparison and inhibition assays indicated that the inhibitory effect of tea against α-amylase was positively related with the enzyme-mediated oxidation degree of tea and black teas containing high contents of theaflavins exhibited the strongest in vitro inhibitory effect. Affinity selection-mass spectrometry-based high-throughput screening revealed that four theaflavins specifically bind to α-amylase. Compared to other compounds, theaflavins showed one order of magnitude higher in vitro inhibitory effects; thus, theaflavins are possibly the dominant α-amylase inhibitors in tea. A series of “α-amylase–theaflavins” interaction studies jointly demonstrated that theaflavins noncompetitively inhibit α-amylase activity by interacting with the amino acid residues of α-amylase and then inducing changes in the secondary structure. Furthermore, theaflavins (10 mg/kg/d) and black tea extracts (100 mg/kg/d) exhibited comparable hypoglycemic effects as acarbose in diabetic mice.

Optimization of Ultrasound-Assisted Deep Eutectic Solvent Extraction, Characterization, and Bioactivities of Polysaccharide from Pericarpium Citri Reticulatae.

The ultrasonic-assisted deep eutectic solvent method was used to extract the polysaccharides of Pericarpium Citri Reticulatae (PCRP), and the ultrasound-assisted DES extraction process was optimized by Box-Behnken response surface test using the extraction rate of the PCRP as an index; the in vitro activities of purified the PCRP(PCRPs-1) were investigated by determining the scavenging rate of DPPH• and ABTS•+ as well as by enzyme inhibition assay. The monosaccharide composition was analyzed by HPLC. The best process conditions for response surface optimization were a material-liquid ratio of 1:37g/mL, water content of 44%, time of 89min, and power of 320 W. The polysaccharide extraction rate was measured to be 5.41%, which was well optimized when compared with that of the ordinary aqueous extraction method of 3.92%. By α-glucosidase and α-amylase inhibition activity test, it showed that the PCRPs-1 had hypoglycemic activity. The DPPH radical scavenging activity test and ABTS + scavenging activity test indicated that the PCRPs-1 had good biological activity. Analysis of the monosaccharide fractions showed that the PCRPs-1 consisted of mannose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, and arabinose, with molar ratios of 1:39.24:4.41:8.91:7.83:86.00:1.02:9.17. The activity studies showed that PCRPs-1 possessed certain hypoglycaemic and antioxidant activities.

Novel carbazole-oxadiazole derivatives as anti-α-glucosidase and anti-α-amylase agents: Design, synthesis, molecular docking, and biological evaluation

To find novel inhibitors of α-glucosidase and α-amylase, a series of new carbazole-oxadiazole derivatives (6a-6n) were prepared, and screened for their anti-α-glucosidase and anti-α-amylase effects. Most of the tested derivatives showed different degrees of α-glucosidase and α-amylase inhibitory activity (IC50: 21.39 ± 0.69–92.05 ± 1.54 μM, 45.53 ± 1.50–126.14 ± 6.33 μM, respectively) compared to the standard acarbose (IC50: 427.00 ± 9.56 μM, 24.68 ± 1.10 μM, respectively). Thereinto, 6c (IC50 = 21.39 ± 0.69 μM) displayed the most effective anti-α-glucosidase activity and 6e presented the best anti-α-amylase activity with an IC50 value of 45.53 ± 1.50 μM. Lineweaver-Burk plot analysis suggested that 6c and 6e behaved as mixed α-glucosidase inhibitor and mixed α-amylase inhibitor, respectively. The results of circular dichroism, atomic force microscope, and molecular docking simulation exposed interaction mechanisms between two preferred compounds (6c and 6e) and their corresponding enzymes. Combined with the possible properties of reducing the elevation in postprandial blood glucose, oral activity, positive bioavailability, and low cytotoxicity of 6c and 6e, it could be concluded that the target derivatives may be able to act as lead molecules for the development of new hypoglycemic agents.

Physicochemical Characterization and Biological Properties of Polysaccharides from Alpiniae oxyphyllae Fructus.

Polysaccharides (AOPs) were extracted from Alpiniae oxyphyllae fructus using three distinct methods: hot water (AOP-HW), hydrochloric acid (AOP-AC), and NaOH/NaBH4 (AOP-AL). This study systematically investigated and compared the physicochemical properties, structural characteristics, antioxidant activities, and α-amylase inhibitory activities of the extracted polysaccharides. Among the three AOPs, AOP-AC exhibited the highest yield (13.76%) and neutral sugar content (80.57%), but had the lowest molecular weight (121.28 kDa). Conversely, AOP-HW had the lowest yield (4.54%) but the highest molecular weight (385.42 kDa). AOP-AL was predominantly composed of arabinose (28.42 mol%), galacturonic acid (17.61 mol%), and galactose (17.09 mol%), while glucose was the major sugar in both AOP-HW (52.31 mol%) and AOP-AC (94.77 mol%). Functionally, AOP-AL demonstrated superior scavenging activities against DPPH, hydroxyl, and ABTS radicals, whereas AOP-AC exhibited the strongest inhibitory effect on α-amylase. These findings indicate that the extraction solvent significantly influences the physicochemical and biological properties of AOPs, thus guiding the selection of appropriate extraction methods for specific applications. The results of this study have broad implications for industries seeking natural polysaccharides with antioxidant and enzymatic inhibitory properties.

Antioxidant, α-amylase, and α-glucosidase inhibitory activities of onion (Allium cepa) and shallot (Allium oscalonicum L.) in food ingredients

AbstractBoth onion and shallot are the most common ingredients to use for many recipes. Consuming onion and shallot provide health benefits including antidiabetic effects. However, the benefits of onion and shallot mixture at different ratios have not been studied in terms of total phenolic content, total antioxidant capacity, superoxide dismutase (SOD)-like activity, and antidiabetic effects. Our study revealed that shallot significantly increased total phenolic content in the mixture from 492 ± 32 μg mL−1 (100% v/v onion) to 803 ± 24 μg mL−1 (100% v/v shallot) depending on the ratios of shallot in the mixture. Shallot also significantly enhanced total antioxidant capacity, SOD-like activity, α-amylase inhibition, and α-glucosidase inhibition in the mixture. Shallot juice exhibited the highest percentage inhibition of α-amylase activity (40.51 ± 1.57%) and α-glucosidase activity (89.61 ± 2.85%) in comparison to those of onion juice and the mixture. In addition, significant positive correlation between phenolic compound and different variables was observed (P &lt; 0.05). Phenolic compounds present in onion and shallot are probably responsible for many health benefits including antidiabetic effects.

Kigelia africana fruit fractions inhibit in vitro alpha-glucosidase activity: a potential natural alpha-glucosidase inhibitor

BackgroundDiabetes affects 75% of people in low-income countries, where conventional drugs like metformin are available, but newer drugs like alpha-glucosidase inhibitors are not accessible to most Southern African patients.AimTo evaluate the α-glucosidase and α-amylase inhibitory activities of fractionated aqueous extracts of Kigelia africana fruit (KAFE) and their phytochemical fingerprints using gas chromatography-mass spectrometry (GC–MS).Materials and methodsWe studied K. africana fruit fractions' inhibitory effects on alpha-glucosidase and alpha-amylase using bioassay-guided fractionation, and analyzed their phytochemical profiles with GC–MS.Key findingsBoth the aqueous extract and ethyl acetate fraction of the aqueous extract exhibited a low dose-dependent inhibition of alpha-amylase activity (p < 0.0001). At a concentration of 500 μg/mL, the aqueous extract caused an alpha-glucosidase inhibition of 64.10 ± 2.7%, with an estimated IC50 of 193.7 μg/mL, while the ethyl acetate fraction had an inhibition of 89.82 ± 0.8% and an estimated IC50 of 10.41 μg/mL. The subfraction G, which had the highest alpha-glucosidase inhibitory activity at 85.10 ± 0.7%, had significantly lower activity than the ethyl acetate fraction. The most bioactive fraction was found to contain 11"(2-cyclopenten-1-yl) undecanoic acid, ( +)- and cyclopentane undecanoic acid as well as the indole alkaloids Akuammilan-17-ol-10-methoxy, N-nitroso-2-methyl-oxazolidine and epoxide Oxirane2.2″ -(1.4-butanediyl) bis-.ConclusionThe K. africana fruit fraction demonstrated significant alpha-glucosidase inhibitory activity, while its alpha-amylase inhibitory activity was limited. This study suggests a potential natural alpha-glucosidase inhibitor and phytocompounds that could serve as leads for developing antidiabetic agents.