Α-glucosidase Inhibition Assay Research Articles

Potential nanomedicinal applications and physicochemical nature of Hyphaene thebaica-reduced nano-samaria.

Herein we described the biofabrication of samarium oxide nanoparticles (HT-Sm2O3 NPs) by applying the aqueous fruit extract of Hyphaene thebaica was utilized as an eco-friendly chelating agent. The prepared NPs were subjected to various physicochemical properties and potential in biomedical applications. X-ray Diffraction (XRD) pattern revealed sharp peaks that corroborated with the Joint Committee on Powder Diffraction Standards (JCPDS) card no. 00-042-1464. Crystallite size obtained from Debye-Scherrer approximation and Williamson-Hall (W-H) plot was 28.73 and 69.3 nm, respectively. Optical bandgap was calculated by employing Kubelka-Munk (K-M) function and was found to be ~4.58 eV. Raman shift was observed at 121, 351, 424-, and 561 cm-1. Photoluminescence (PL) spectra revealed two major peaks positioned at 360 and 540 nm. The high-resolution transmission electron microscopy (HR-TEM) analysis of HT-Sm2O3 nanoparticles (NPs) showed that they predominantly have spherical to cuboidal shapes. Additionally, the selected area electron diffraction (SAED) pattern presented spotty rings, indicating a high level of crystallinity in these NPs. The potential nanomedicine applications were studied using diverse bioassays using different treatments. The antioxidant activity demonstrated 45.71% ± 1.13% inhibition at 1000 μg/mL. Brine shrimp lethality assay revealed the highest cytotoxicity of 46.67% ± 3.33% at 1000 μg/mL and LC50 value of 1081 μg/mL. HT-Sm2O3 NPs exhibited inhibition of angiogenesis (20.41% ± 1.18%) at of 1000 μg/mL. MTT assay results indicated that HT-Sm2O3 NPs exhibit inhibitory effects on cell lines. Specifically, these NPs showed an IC50 value of 104.6 μg/mL against 3T3 cells. Against MCF-7 cells, the NPs demonstrated an IC50 value of 413.25 μg/mL. Additionally, in the inhibition of acetylcholinesterase (AChE), the newly synthesized NPs showed an IC50 value of 320 μg/mL. The antidiabetic assessment through α-glucosidase and α-amylase inhibition assays revealed, an IC50 value of 380 μg/mL for α-glucosidase and 952 μg/mL for α-amylase was calculated. Overall, our study suggested that the Sm2O3 NPs possess moderate anticancer, cholinesterase inhibition, and antidiabetic potential, however, needs further assessment. RESEARCH HIGHLIGHTS: In this work, nano-samaria is synthesized using an eco-friendly and green approach. The nanoparticles were characterized using techniques such as Raman, HR-TEM, FTIR, DRS, XRD, and so on, and the applications were studied using multiple in vitro bioassays for Diabetes, Alzheimer, and Cancer. The nano-samaria revealed good potential for potential biomedical applications.

Assessing anticancer, antidiabetic, and antioxidant capacities in green-synthesized zinc oxide nanoparticles and solvent-based plant extracts

Cancer and diabetes represent significant challenges in the field of biomedicine, with major and global impacts on public health. Acacia nilotica, commonly called 'gum arabic tree,' is recognized for its unique biomedical properties. The current study aimed to investigate the pharmacological potential of A. nilotica-based zinc-oxide nanoparticles (ZnO-NPs) in comparison to the ethanol and methanol-based extracts against cancer, diabetes, and oxidative stress. Green synthesis of ZnO-NPs was performed using barks of Acacia nilotica. Different techniques for the characterization of ZnO-NPs, including UV–Visible spectroscopy, Scanning Electron Microscopy, Fourier Transmission Infrared (FT-IR) spectroscopy, and X-ray Diffraction (XRD), were utilized. The morphological analysis of ZnO-NPs revealed that the fine NPs have mean particle sizes of 15 ± 1.5 nm. For the solvent based-extraction, leaves and barks were utilized and dissolved into ethanol and methanol for further processing. The MTT assay revealed that the optimum concentration of ZnO-NPs to inhibit the proliferation of liver cancer cell line HepG2 was 100 μg/mL where 67.0 % inhibition was observed; and both ethanol- and methanol-based extracts showed optimum inhibition at 100 μg/mL. The DPPH assay further demonstrated that 250 μg/mL of ZnO-NPs and 1000 μg/mL of both ethanol- and methanol-based extracts, as the optimum concentration for antioxidant activity (with 73.1 %, 68.9 % and 68.2 % inhibition respectively). The α-Glucosidase inhibition assay revealed that 250 μg/mL of ZnO-NPs and 10 μg/mL of both ethanol- and methanol-based extracts as the optimum concentration for antidiabetic activity (with 95 %, 93.7 % and 93.4 % inhibition respectively). The study provided interesting insights into the efficacy and reliability of ZnO-NPs for potential pharmacological application. Further research should be focused on examining specific pathways and the safety of ZnO-NPs in comparison to solvent-based extracts.

Antibacterial, antidiabetic and antioxidant bioevaluation of Calamus leptospadix Griff. and isolation of a flavan type compound

The plant based natural products have always been a rich source of bioactive molecules for drug discovery. The tender shoots of Calamus leptospadix Griff., an edible medicinal plant was extracted using methanol, water and ethanol as three different solvents to study the effect of the extracting solvents and temperature on their antioxidant, antidiabetic and antibacterial properties and total phenolic and flavonoid contents. The antioxidant properties were determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assay. The α-glucosidase inhibitory assay was carried out to determine the antidiabetic potential. The antibacterial properties of the extracts were determined against four strains of bacterial species viz. Bacillus subtilis, Streptococcus pneumoniae, Escherichia coli and Citrobacter freundii using Broth macro dilution method.The methanolic extracts of the plant were found to possess the highest total phenolic and total flavonoid contents. In the antioxidant assays, the cold methanolic extract was found to exhibit the highest DDPH radical scavenging activity and ferric-reducing antioxidant power. In the antidiabetic assay, the extract exhibited better α-glucosidase inhibitory potential than that of the positive control acarbose. It was also found to be effective against both gram-positive and gram-negative strains in the antibacterial assay. A flavan-type compound 4-(5,7-dimethoxychroman-2-yl)phenol was isolated from the most bioactive cold methanolic extract of the plant and characterised from its XRD, 1H- and 13C-NMR, HRMS and IR data.

Green synthesis of CuO/TiO2 and ZnO/TiO2 nanocomposites using Parkia timoriana bark extract: Enhanced antioxidant and antidiabetic activities for biomedical applications

The green method provides stable, rapid, and eco-friendly methods for synthesis nanoparticles with plant extract as capping and reducing agents. This method renders biocompatibility, scalability, and potential medical applications of nanoparticles. This study green synthesized CuO/TiO2 and ZnO/TiO2 nanocomposites using Parkia timoriana bark extract. The synthesized nanocomposites were determined utilizing UV–vis DRS FTIR, XRD, TGA, AFM, FE-SEM, E-DAX, HR-TEM, and XPS. Antioxidant assay and antidiabetic studies revealed the biological activity of nanocomposites. The antioxidant property in ZnO/TiO2 (84.07 %) was higher than in CuO/TiO2 nanocomposites (72.76 %). The IC50 value of CuO/TiO2 and ZnO/TiO2 in α-amylase inhibition assay was 72.12 μg/mL and 75.95 μg/mL, respectively and IC50 value of CuO/TiO2 and ZnO/TiO2 in α-glucosidase inhibition assay was 30.80 μg/ml and 25.69 μg/ml. Thus, it concludes ZnO/TiO2 nanocomposites exhibited higher antioxidant and antidiabetic activity than CuO/TiO2 nanocomposites. These results show that biosynthesized nanocomposites can be used for treating diseases.

In vitro study of the inhibitory potentials of cold and hot aqueous extract of Vernonia amygdalina, Calotropis procera, and Persea americana on α-glucosidase

Background: The surge in the incidence of diabetes mellitus has spurred heightened interest on alternative and complementary therapies, particularly those derived from medicinal plants. Objective: To assess the α-glucosidase inhibitory activity of cold and hot aqueous extracts of Vernonia amygdalina (bitter leaf), Calotropis procera (locally known as “bomubomu” leaves), and Persea americana (also known as avocado pear) to explore their medicinal applicability. Method: The leaves of V. amygdalina, C. procera, and the seed of P. americana were subjected to cold and hot extraction methods using distilled water. These extracts were specifically targeted for their potential inhibitory effects on α-glucosidase activity, a key enzyme involved in carbohydrate digestion. Results: The α-glucosidase inhibitory assay showed that the extracts from the plants had maximum inhibitory effects at 20 mg/mL. Cold and hot aqueous extracts of V. amygdalina exhibited maximal inhibitory activities of 100% and 86%, respectively, at 20mg/mL. Cold and hot aqueous extracts of C. procera displayed 100% and 91% inhibitory activities, respectively, at 20mg/mL. Similarly, cold and hot extracts of P. americana exhibited the highest inhibitory activities of 77% and 63%, respectively, at 20mg/mL concentration. Conclusions: The findings demonstrated that cold and hot aqueous extracts of Vernonia amygdalina, Calotropis procera, and Persea americana exhibited significant inhibitory activities against α-glucosidase. The observed inhibitory effects suggest the therapeutic potential of these plant extracts as natural remedies for managing post-prandial hyperglycaemia in Type 2 Diabetes mellitus.

In Vitro Analysis of Camellia sinensis Leaf Extract Against Diabetes Mellitus.

Diabetes mellitus (DM) poses a significant global health challenge, with its prevalence steadily increasing. Natural compounds derived from plants have garnered attention for their potential therapeutic effects in managing this metabolic disorder. Camellia sinensis, commonly known as tea, is rich in bioactive compounds exhibiting various pharmacological properties. This study investigates the potential anti-diabetic activity of C. sinensis leaf extract through in vitro analysis. Camella sinensisleaf extract was prepared by grinding the plant's leaf into a powder, mixing it with distilled water, and heating. The antidiabetic activity was assessed through α-Amylase and α-Glucosidase inhibitory assays, employing varying concentrations of the plant extract. Molecular docking analysis utilized Autodock 1.5.6 software (The Scripps Research Institute, California, US)to predict ligand-receptor interactions, guiding subsequent experimental validation. Camella sinensisleaf extract exhibited high phenolic content, suggesting potential in managing hyperglycemia. Tannins may aid glucose absorption and inhibit adipogenesis, making them promising for non-insulin-dependent DM (NIDDM). Terpenoids, with antioxidant activity, inhibit advanced glycation. Saponins and steroids were absent. Molecular docking revealed residues like IR, IRS1, and AS160 with significant impact on α-Amylase and α-Glucosidase, comparable to metformin. The findings of this study highlight the promising potential of C. sinensis leaf extract in managing hyperglycemia associated with DM. The high phenolic content aids in glucose regulation. Specifically, the presence of tannins suggests a potential role in modulating glucose absorption and inhibiting adipogenesis, which could be particularly beneficial for individuals with NIDDM.These findings provide valuable insights into the molecular mechanisms underlying the potential therapeutic efficacy of C. sinensis leaf extract against DM, paving the way for further research and development of novel therapeutic interventions in diabetes management.

Exploring the inhibitory action of betulinic acid on key digestive enzymes linked to diabetes via in vitro and computational models: approaches to anti-diabetic mechanisms

ABSTRACT Phytochemicals are now increasingly exploited as remedial agents for the management of diabetes due to side effects attributable to commercial antidiabetic agents. This study investigated the structural and molecular mechanisms by which betulinic acid exhibits its antidiabetic effect via in vitro and computational techniques. In vitro antidiabetic potential was analysed via on α-amylase, α-glucosidase, pancreatic lipase and α-chymotrypsin inhibitory assays. Its structural and molecular inhibitory mechanisms were investigated using Density Functional Theory (DFT) analysis, molecular docking and molecular dynamics (MD) simulation. Betulinic acid significantly (p < 0.05) inhibited α-amylase, α-glucosidase, pancreatic lipase and α-chymotrypsin enzymes with IC50 of 70.02 μg/mL, 0.27 μg/mL, 1.70 μg/mL and 8.44 μg/mL, respectively. According to DFT studies, betulinic acid possesses similar reaction in gaseous phase and water due to close values observed for highest occupied molecular orbital (HOMO) and lowest occupied molecular orbital (LUMO) and the chemical descriptors. The dipole moment indicates that betulinic acid has high polarity. Molecular electrostatic potential surface revealed the electrophilic and nucleophilic attack-prone atoms of the molecule. Molecular dynamic studies revealed a stable complex between betulinic acid and α-amylase, α-glucosidase, pancreatic lipase and α-chymotrypsin. The study elucidated the potent antidiabetic properties of betulinic acid by revealing its conformational inhibitory mode of action on enzymes involved in the onset of diabetes.

In vitro cholinesterases, tyrosinase, α-glucosidase inhibitory and anticancer effects of novel silicon phthalocyanines containing geraniol/phytol

The axially silicon phthalocyanines, consisting of different acyclic hydrocarbons, were generated by SiPcCl2 reacting with either geraniol or phytol in toluene in the presence of NaH. FT-IR, UV–Vis, MALDI TOF, and NMR spectroscopy all provided information about the structures of silicon phthalocyanines. The cholinesterase, tyrosinase, and α-glucosidase inhibitory effects of G-SiPc and P-SiPc were tested using spectrophotometric assays. The IC50 values of G-SiPc and P-SiPc were 7.22 ± 0.53 and 11.28 ± 2.73 µM for AChE; 70.05 ± 3.00 and 60.55 ± 3.80 µM for BuChE. In addition, G-SiPc and P-SiPc inhibited the tyrosinase enzyme with IC50 values of 280.36 ± 7.92 µM and 40.51 ± 3.88 µM, respectively. P-SiPc had about seven times stronger inhibitory properties than G-SiPc. The substances exhibited less inhibition than acarbose in the α-glucosidase inhibitory assay. Finally, the cytotoxic effects of G-SiPc and P-SiPc were investigated using the MTT assay on L-929 mouse fibroblast cells as normal cells. G-SiPc and P-SiPc did not reach IC50 values up to 100 μM.

In Vitro Alpha-Glucosidase Inhibitory Effect of Etlingera Elatior Ethanol Extract Growing in Gayo Highland, Aceh Province, Indonesia

Background The prevalence of diabetes mellitus (DM) is increasing overtime, potentially leading to various severe health complications and mortality. Despite therapeutic agents have currently been developed, unexpected adverse effects are inevitable. Hence, safe and effective medications such as those of plant origin are critical to prevent unexpected complication in DM sufferers. Etlingera elatior has been widely used as spice and traditional medicine to treat diabetes in Aceh Province, Indonesia. However, study regarding α-glucosidase inhibitory effect of E. elatior growing in Gayo highlands, Aceh, Indonesia, is completely lacking. The aim of this study was to evaluate in vitro α-glucosidase inhibitory effect of E. elatior ethanol extracts (EEEE) growing in Gayo highlands, Aceh Province, Indonesia. Methods Antioxidant activity was determined using DPPH procedure, whereas α-glucosidase inhibition assay was carried out using spectrophotometric method. Data analysis was performed using One-Way Analysis of Variance (ANOVA), followed by Duncan’s multiple range test at α=0.05. Results Phytochemical analysis revealed the presence of total phenolic (TPC), total flavonoid (TFC), and total tannin (TTC) content in all E. elatior plant parts, in which the highest TPC was found in the stem (158.38 GAE/g), whereas the highest TFC and TTC was obtained in the rhizome extracts. The extract of fruit showed the strongest antioxidant activities, followed by the stem and leaf, with IC50 of 2.381 μg/mL, 6.966 μg/mL, and 19.365 μg/mL, respectively. All E. elatior extracts revealed a significant inhibitory activity against α-glucosidase at the concentration of 500 μg/mL, in which the stem extract showed the most effective α-glucosidase inhibitory effect with IC50 value of 5.15 μg/mL, suggesting its promising potential as antidiabetic agent. Conclusions This study highlights E. elatior potency as a novel source of antioxidant and natural antidiabetic compounds that are useful for the prevention and treatment of diabetes.

Assessment of anti-diabetic properties of Ziziphus oenopolia (L.) wild edible fruit extract: In vitro and in silico investigations through molecular docking analysis

Abstract Globally, healthcare is concerned about the rising prevalence of type 2 diabetes. Phytochemicals from medicinal plants have shown great promise in improving human health. The present study aimed to determine the secondary metabolites of Ziziphus oenopolia (L.) fruit extract that contribute to its anti-diabetic activity. The anti-diabetic properties were assessed by in vitro and in silico approaches using α-amylase and α-glucosidase inhibitory assays. Gas chromatography and mass spectroscopy analyses were used to profile Z. oenopolia fruit contents, and a total of four bioactive chemicals and eight phytocompounds were tentatively identified, including flavonoids, terpenoids, phenols, steroids, tannins, and saponins. The Z. oenopolia fruit hydroalcoholic extract inhibits α-amylase and α-glucosidase enzymes in a dose-dependent manner (IC50 = 328.76 and 337.28 µg/mL, R 2 = 0.979 and 0.981). Additionally, phytochemicals found in Z. oenopolia fruit exhibit the ability to inhibit anti-diabetic targets, specifically α-amylase and α-glucosidase (2QV4 vs 3A4A; correlation coefficient, r = 0.955), as demonstrated by computational analysis. This establishes the fruit as a promising and environmentally friendly option for treating hyperglycemia, highlighting the positive correlation between anti-diabetic objectives.

Anti-diabetic potential of Chamaerops humilis L. aerial parts: Phenolic compounds with α-amylase and α-glucosidase inhibitory activates in-vitro, in-vivo and in-silico studies

Five compounds were isolated from the aerial parts of Chamaerops humilis L. and characterized as tricin-7-rutinoside (1), tricin (2), dihydrotricin (3) diasteroisomer of tricin 4′-O(erythro-β-guaiacyl glyceryl) ether (salcolin A)(4a), tricin-4′-O-(threo-β-guaiacyl glyceryl) ether (salcolin B) (4b) and (-)-(5s, 6s)-5,6-dihydro-3,8,10-trihydroxy-5-(4-hydroxy-3-methoxyphenyl)-6-hydroxymethyl-2,4-dimethoxy 7H benzo [e] xanthen-7-one (5). Their structures were elucidated by comparing their spectral data with those reported in the literature. To the best of our knowledge, compounds (3-5) were reported here for the first time from Chamaerops humilis. The methanolic extract of Chamaerops humilis (CHME) and the five isolated compounds were studied for its anti-diabetic effect using in vitro α-glucosidase and α-amylase inhibitory assay that showed a significant activity. The toxicological study indicated that CHME was safe up to 5000 mg/kg bw. Two doses were selected for the in vivo study (800 and 1600 mg/kg bw) and orally administered to high fat diet/streptozotocin-induced diabetic rats for 10 consecutive days. The results revealed that the CHME improved the blood glucose levels in a dose dependent manner, the dose 1600 mg/kg showed the best results dependently along the period of the experiment. CHME and the five isolated compounds were evaluated in silico for their anti-diabetic effect. The anti-inflammatory effect of CHME (1600 mg/kg bw) was proved by significant downregulation of expression for interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and matrix metalloproteinase-1 (MMP-1) genes. In conclusion, CHME and its constituents may be a potential hypoglycemic agent working through the anti-inflammatory and enzyme inhibitory pathways. The docking studies demonstrated that compounds Tricin7-rutinoside and Salcolin isomers had promising binding energies of -9.10 kcal/mol and -8.70 kcal/mol, respectively, against α-amylase. These binding energies were superior to that of acarbose, which had a binding energy of -7.60 kcal/mol. In addition, docking analysis provided promising results for the inhibition of α-glucosidase by Tricin7-rutinoside and Dihydrotricin with binding affinity -7.9 kcal/mol and -7.9 kcal/mol, respectively while the binding affinity of acarbose is -6.40 kcal/mol. Overall, the methanolic extract from Chamaerops humilis exhibited good in silico of α-amylase and α-glucosidase enzyme inhibition potential. These findings suggest that these compounds may have potential as anti-diabetic agents, with further research needed to verify their efficacy and safety.

Increasing structure diversity of farnesylated chalcones by a fungal aromatic prenyltransferase

Farnesylated chalcones were favored by researchers due to their different biological activities. However, only five naturally occurring farnesylated chalcones were described in the literature until now. Here, the farnesylation of six chalcones by the Aspergillus terreus aromatic prenyltransferase AtaPT was reported. Fourteen monofarnesylated chalcones (1F1−1F5, 2F1−2F3, 3F1, 3F2, 4F1, 4F2, 5F1, 6F1, and 6F2) and a difarnesylated product (2F3) were obtained, enriching the diversity of natural farnesylated chalcones significantly. Ten of them are C-farnesylated products, which complement O-farnesylated chalcones by chemical synthesis. Fourteen products have not been reported prior to this study. Nine of the produced compounds (1F2−1F5, 2F1−2F3, 5F1, and 6F1) exhibited inhibitory effect on α-glucosidase with IC50 values ranging from 24.08 ± 1.44 to 190.0 ± 0.28 μM. Among them, compounds 2F3 with IC50 value at 24.08 ± 1.44 μM and 1F4 with IC50 value at 30.09 ± 0.59 μM showed about 20 times stronger than the positive control acarbose with an IC50 at 536.87 ± 24.25 μM in α-glucosidase inhibitory assays.

Comparative antioxidant, antibacterial, and antidiabetic activities of in vitro-grown callus and wild-grown various parts of Piper longum L

BackgroundPiper longum L. is a tropical and subtropical medicinal plant that has been used as antidiabetic, diarrhea, stomachache, cough, asthma, and bronchitis since ancient times. The in vitro-grown callus from the leaf, however, has not been tested and utilized for any of these conditions. Thus, this research pursues to assess the comparative study of antioxidant, antibacterial, and antidiabetic activities of in vitro-grown callus and various parts of Piper longum-grown in the wild. MethodsThe antioxidant activity of crude extracts and the fractions were determined by DPPH (1,1-diphenyl-2-picrylhydrazyl) free-radical scavenging assay, the antibacterial activity by agar-well diffusion method, and antidiabetic activity by α-amylase and α-glucosidase inhibition assay. In addition, the total phenol content (TPC) and total flavonoid contents (TFC) were calculated using Folin-Ciocalteau reagent and aluminum chloride complex-forming assay respectively. ResultsThe highest antioxidant activity (IC50=134.81±1.16 µg/mL), TPC (41.22±0.50 mg of GAE/g dry weight), and TFC (73.41±0.53 mg of QE/g dry weight) were obtained in the dichloromethane (DCM) fraction of root than other crude extracts and fractions. The DCM fractions of root exhibited the minimum inhibitory concentration (MIC) at 5.0 mg/mL and minimum bactericidal concentration (MBC) of 8.35 mg/mL to the Staphylococcus aureus. Moreover, the DCM fraction of root showed the highest α-amylase and α-glucosidase inhibition (IC50=365.21±31.02 and 489.07±27.96 µg/mL) than other crude extracts and fractions. To the best of our information, comparative antioxidant (IC50=206.61±0.64 µg/mL), antibacterial (suppressed 80 % of tested bacteria), and antidiabetic (IC50=1165.15±15.63 and 1304.76±12.43 µg/mL) properties of the in vitro-grown callus were recorded for the first time in P. longum, and were found to be comparative to those of the wild-grown parts. ConclusionsThese results showed that wild-grown P. longum roots, particularly the DCM fraction, could be an important source of natural antioxidants, antimicrobials, and antidiabetics for better curative uses than other wild-grown parts and in vitro-grown callus. In vitro-grown callus, however, could be used as a natural drug source and used to conserve P. longum in its natural habitats in the future.

Phytochemical profiling, antidiabetic, antiobesity, and antibacterial activities of Cometes abyssinica

This study aims to complete my chemical and biological studies on Cometes abyssinica (CA). The chemical profile was reported by LC-ESI-TOF-MS and GC-MS analyses. Antidiabetic (α-Glucosidase and a-amylase inhibitory activity assay), antiobesity (Lipase inhibitory activity assay), and antibacterial activity (agar well diffusion assay) were determined. The GC-MS analysis led to the identification of 27 hydrocarbons representing 93.4% of the total hydrocarbon content in hexane extract. 11-Octadecenoic acid, methyl ester (28.07%), citronellol (9.31%), hexadecanoic acid, methyl ester (7.64%), phytol (5.93%), and 10-epi-γ-eudesmol (4.91%) were the major components. The LC-ESI-TOF-MS analyses of aqueous-methanolic extract led to the identification of 99 secondary metabolites including phenolics, flavonoids, alkaloids, and vitamins. The percentages of inhibition of the n-hexane, chloroform, ethyl acetate, and methanol extracts of CA were evaluated against α-glucosidase, α-amylase, and pancreatic lipase enzymes at different concentrations. Hexane extract showed the most powerful α-glucosidase and α-amylase inhibitory activity with IC50 value of 0.22 and 0.27 mg/ml comparing with acarbose (IC50 0.43 and 0.38), respectively. Among all CA extracts, only ethyl acetate extract revealed potent antiobesity as a lipase inhibitory activity with IC50 value of 0.079 mg/ml comparing with orlistat (IC50 0.11 mg/ml). CA extracts showed mild-weak antibacterial effect against Pseudomonas aeruginosa and Bacillus cereus. KEY WORDS: Cometes abyssinica, Chemical constituents, α-Amylase inhibitors, α-Glucosidase inhibitors, Lipase inhibitors Bull. Chem. Soc. Ethiop. 2024, 38(4), 1051-1067. DOI: https://dx.doi.org/10.4314/bcse.v38i4.19

The effect of extraction method on biological activity and phytochemical content of Artocarpus heterophyllus (jackfruit) leaves extract concurrent with its principal component analysis

Artocapus heterophyllus (jackfruit) is available in abundance in tropical regions. The present study explored the effect of different extraction method i.e. maceration, ultrasonication and both of ultrasonication and maceration on its biological activity (antioxidant, antidiabetes and antibacterial activities) and phytochemical content of Artocarpus heterophyllus (jackfruit) leaves extract. Jackfruit leaves were extracted using ethanol as solvent. The capability of jackfruit leaves extract to scavenge radicals was evaluated using a DPPH (2,2-diphenyl-1-picryl-hydrazyl) assay, β-carotene bleaching assay and reducing power assay. The total phenolic content (TPC) was assessed using the Folin- Ciocalteau method. Its antibacterial activity was assessed using the disc diffusion and microdilution method against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhimurim and Escherichia coli. The α-glucosidase inhibitor assay was conducted using α-glucosidase from Saccharomyces cerevisiae. The results revealed that ulrasonication method give the highest antioxidant activity in three metode used, i.e. DPPH assay with IC50 of 42.51 µg/mL, β-carotene bleaching assay of 57.64%, reducing power assay of 919 mg GAE/g. Meanwhile, for α-glucosidase inhibitory assay, ultrasonication method also had the highest value of 83.44% at concentration of 1000 µg/mL. Furthermore, antibacterial assay using disk diffusion method showed ultrasonication had the highest inhibition zone of 7.81 mm at 5 mg/mL against P. aeruginosa, while maceration method had the highest inhibition zone of 8.02 mm at 5 mg/mL against E. coli. These results in accordance with total phenolic content (TPC) of ultrasonication extract which was the highest of 125.06 mg GAE/g. The liquid chromatography-high-resolution mass spectrometry (LC-HRMS) analysis suggested that several bioactive compounds such as phenolic, flavonoid and its derivatives was present in the jackfruit leaves extract. Further analysis using principal component analysis (PCA) revealed that the extraction process affected the metabolite composition of the samples which was confirmed by significant separation of the score plots of extraction methods. The present study revealed that jackfruit leaves is a potent source of natural antibacterial, antioxidants and antidiabetic medicines in functional foods and pharmaceutical industries.

Exploration of the Molecular Mechanism Underlying the Antidiabetic Activity of a Northeast Indian Plant Zingiber rubens Roxb. through Modulation of PKC Phosphorylation

Background: Zingiber rubens Roxb., a new species of the Zingiberaceae family, is found profoundly in the Northeastern region of India. It is a rhizomatous geophyte and grows primarily in the seasonally dry tropical biome native to Indo-China regimens. Objective: The aim is to research the root part of this plant to discover active constituents and evaluate the molecular mechanism of antidiabetic activity Methods: The hydroalcoholic root extract of this plant (HAZR) was evaluated for in-vitro antioxidant assays α-amylase and α-glucosidase inhibition assay. Further, the antidiabetic activity assay was evaluated, exploring the molecular mechanism for modulating oxidative stress in tissue biochemical parameters and HbA1c. To explore the molecular mechanism, we also investigated the inhibition assay of protein kinase C (PKC) phosphorylation in mouse peritoneal macrophages. Results: The experiments' results helped to conclude that HAZR has potent antioxidant and antidiabetic activity and could have been embedded with potent active molecules. They also revealed the mechanism of action as inhibition of PKC phosphorylation, meriting further studies. Conclusion: The present study revealed that HAZR demonstrated its antidiabetic activity against diabetic animal models through oxidative stress-mediated PKC and TGF-β regulation in diabetic individuals.

Aloe juvenna Brandham & S.Carter as α-Amylase Inhibitor and Hypoglycaemic Agent with Anti-inflammatory Properties for Diabetes Management.

Despite Aloe's traditional use, Aloe juvenna Brandham & S.Carter is poorly characterized. Other Aloes are known for their antidiabetic activity. This study describes the antidiabetic potentials and phytoconstituents of the A. juvenna leaves methanolic extract (AJME). Twenty-six phytoconstituents of AJME were described using HPLC/MS-MS. Lupeol and vitexin were isolated using column chromatography. The antidiabetic activity of AJME was investigated using an in vivo high-fat diet/streptozotocin-induced diabetic rat model and in vitro α-glucosidase and α-amylase inhibitory activity assays. AJME demonstrated its α-amylase inhibitory activity (IC50=313±39.9 ppm) with no effect on α-glucosidase. In vivo, AJME dose-dependently improved hyperglycaemia in a high-fat diet/streptozotocin-induced diabetic rat model. Notably, the higher dose (1600 mg/kg) of AJME significantly downregulated serum interleukin-6, tumor necrosis factor-α, and matrix metalloproteinase-1 genes, suggesting its anti-inflammatory effect. These findings indicate AJME's potential as a significant antidiabetic agent through its α-amylase inhibition, hypoglycaemic, and anti-inflammatory properties.

Exploring the multifaceted bioactivities of Lavandula pinnata L. essential oil: promising pharmacological activities.

Introduction: This study investigates the biological activities of Lavandula pinnata essential oil (LPEO), an endemic lavender species from the Canary Islands, traditionally used in treating various ailments. Methods: LPEO was extracted by hydrodistillation and analyzed using GC-MS. Antioxidant activity was assessed by DPPH radical scavenging and total antioxidant capacity assays. Antimicrobial activity was evaluated by disc diffusion, MIC, MBC, and MFC determination against bacterial (Staphylococcus aureus, Micrococcus luteus, Escherichia coli, Pseudomonas aeruginosa) and fungal (Candida glabrata, Rhodotorula glutinis, Aspergillus niger, Penicillium digitatum) strains. Antidiabetic and anti-gout potential were investigated through α-amylase, α-glucosidase, and xanthine oxidase inhibition assays. Antityrosinase activity was determined using a modified dopachrome method. Cytotoxicity was assessed by MTT assay against breast (MCF-7, MDA-MB-468), liver (HepG2), colon (HCT-15) cancer cells, and normal cells (PBMCs). Results and discussion: LPEO exhibits potent antiradical activity (IC50 = 148.33 ± 2.48μg/mL) and significant antioxidant capacity (TAC = 171.56 ± 2.34μg AA/mg of EO). It demonstrates notable antibacterial activity against four strains (Staphylococcus aureus, Micrococcus luteus, Escherichia coli, and Pseudomonas aeruginosa) with inhibition zones ranging from 18.70 ± 0.30mm to 29.20 ± 0.30mm, along with relatively low MIC and MBC values. LPEO displays significant antifungal activity against four strains (Candida glabrata, Rhodotorula glutinis, Aspergillus niger, and Penicillium digitatum) with a fungicidal effect at 1mg/mL, surpassing the positive control (cycloheximide), and MIC and MFC values indicating a fungicidal effect. It exhibits substantial inhibition of xanthine oxidase enzyme (IC50 = 26.48 ± 0.90μg/mL), comparable to allopurinol, and marked inhibitory effects on α-amylase (IC50 = 31.56 ± 0.46μg/mL) and α-glucosidase (IC50 = 58.47 ± 2.35μg/mL) enzymes.The enzyme tyrosinase is inhibited by LPEO (IC50 = 29.11 ± 0.08mg/mL). LPEO displays moderate cytotoxic activity against breast, liver, and colon cancer cells, with low toxicity towards normal cells (PBMC). LPEO exhibits greater selectivity than cisplatin for breast (MCF-7) and colon (HCT-15) cancer cells but lower selectivity for liver (HepG2) and metastatic breast (MDA-MB-468) cancer cells. These findings suggest the potential of LPEO as an antioxidant, antimicrobial, anti-gout, antidiabetic, and anticancer agent.

Qualitative chemical compounds analysis and in vitro estimation of antiproliferative, antidiabetic and anti-Alzheimer’s disease effects of Ononis natrix (L.) family Fabaceae

The O. natrix belongs to the family Fabaceae and is distributed in Jordan. Different species of the family Fabaceae contain chemical compounds that may have potential antiproliferative, antidiabetic, and anti-Alzheimer’s disease. High-performance liquid chromatography (HPLC) was applied to analyse the phenolic compounds found in O. natrix methanolic extract. Using the MTT assay, the antiproliferative action was studied. The enzymes α-glucosidase and butyrylcholinesterase inhibition assays were used to study the antidiabetic and anti-Alzheimer’s disease actions, respectively, of methanolic extract of O. natrix. Eleven phenolics and seven flavonoids were identified in the methanolic extract of O. natrix by HPLC. The highest phenolics and flavonoids were gallic acid (1.25 mg/100 g dry weight) and rutin (1.44 mg/100 g dry weight), respectively. The most cancer cell lines influenced by the extract of O. natrix were PC-3 (IC50 = 55 ± 2 µg/mL) and HepG-2 (IC50 = 68 ± 2 µg/mL) compared to positive control cisplatin. However, the cancer cell lines CaCo-2, MCF-7, and HeLa showed IC50 values of 109 ± 2 µg/mL, 123 ± 2 µg/mL, and 79 ± 1 µg/mL, respectively, related to cisplatin. The O. natrix extract inhibited the α-glucosidase enzyme and butyrylcholinesterase enzyme by 84% and 86%, respectively compared to positive controls acarbose and rivastigmine. The O. natrix may possess antiproliferative effects against prostate cancer and hepatocellular carcinoma. It also may have antidiabetic and anti-Alzheimer’s disease effects.

Vitis vinifera L. seed standardized extract; a promising therapeutic against metabolic syndrome induced by high-fat/high-carbohydrate diet and streptozotocin in rats

Metabolic syndrome (MetS) is a group of abnormal disorders; hypertension, glucose intolerance, dyslipidemia, proinflammatory, and prothrombotic states, affecting approximately 14 % of the world's population. The potential of grape seeds extract (GSE) supplementation to improve the metabolic disturbances and their related conditions like obesity, type 2 diabetes, and nonalcoholic fatty liver disease was investigated in this study. In-vitro metabolic syndrome assays were investigated through α-amylase, α-glucosidase, lipase, lipoxygenase (LOX), cyclooxygenases (COX-1 and COX-2), renin and angiotensin converting enzyme (ACE) inhibition assays. Additionally, in-vivo rat model of high-fat-high-carbohydrate diet (HFD)-induced MetS was established, where metformin (MT) (200 mg/kg) was used as a reference drug and GSE was given at 100 and 200 mg/kg by oral gavage. GSE was standardized using HPLC analysis for the major reported compound; catechin which should be ≥ 160.76 ± 5.52 μg/mL. Total phenolic content of GSE was 21.12±0.61 µg gallic acid equivalent/1 mg extract and total flavonoid content was 23.81±0.64 µg rutin equivalent/1 mg extract. In-vitro assays revealed the potential of GSE to manage the metabolic syndrome, besides its strong antioxidant capacity. Treatment with GSE (100 mg/kg and 200 mg/kg) markedly (P < 0.05) controlled the weight gain, improved the metabolic pathways (total glucose, cholesterol, triglycerides, AST, and ALT), oxidative stress parameters (MDA, GSH, and catalase) and inflammatory biomarkers in HFD fed rats. GSE downregulated the expression of insulin resistance gene (IR) and some inflammatory related genes (TNF-α and NF-κB), additionally it improved the pathological features of metabolic conditions and upgraded the expression of Nrf2 compared to HFD group. The superior effects were owned to the high dose of GSE, 200 mg/kg b.wt. (P < 0.05, P < 0.001). All results sustenance the beneficial effects of the standardized GSE in the management of metabolic syndrome.