Maesa indica: a nutritional wild berry rich in polyphenols with special attention to radical scavenging and inhibition of key enzymes, ?-amylase and ?-glucosidase.
ABSTRACT: The present study was aimed to evaluate the nutritional, antioxidant properties and inhibition of the key enzyme such as ?-amylase and ?-glucosidase from the fruits of Maesa indica. The results revealed that M. indica fruits possess an enormous amount of protein (45.68 mg/g), carbohydrates (25.12 mg/g) and mineral elements. The acetone extract were capable of hunting radicals by providing electrons and break chain reaction, especially in ABTS·+ (3719.23 µmol TE/g extract), OH· (66.50 %) and NO· (81.50 %) radical scavenging assays. The methanol extract showed a strong inhibition towards ?-amylase and ?-glucosidase (IC50 of 37.80 and 23.74 µg/mL, respectively). HPLC analysis enumerate that both extracts illustrates the presence of polyphenolic compounds namely quercetin, caffeic acid, rutin and chlorogenic acid.
Project description:The fruits of some Cornus species (dogwoods) are used in traditional medicine and considered potential anti-diabetic and hypolipemic agents. The aim of the study was to determine the ability of extracts from Cornus alba (CA), Cornus florida (CF), and Cornus sanguinea (CS) to inhibit digestive enzymes namely ?-amylase, pancreatic lipase, and ?-glucosidase, as well as isolation of compounds from plant material with the strongest effect. In addition, the phytochemical profile and antioxidant activity of extracts from three dogwoods were compared with HPLC-DAD-MS/MS and DPPH scavenging assay, respectively. Among the aqueous-ethanolic extracts, the activity of ?-amylase was the most strongly inhibited by the fruit extract of CA (IC50 = 115.20 ± 14.31 ?g/mL) and the activity of ?-glucosidase by the fruit of CF (IC50 = 38.87 ± 2.65 ?g/mL). Some constituents of CA fruit extract, such as coumaroylquinic acid, kaempferol, and hydroxytyrosol derivatives, were isolated. Among the three species of dogwood studied, the greatest biological potential was demonstrated by CA extracts, which are sources of phenolic acids and flavonoid compounds. In contrast, iridoid compounds or flavonoid glycosides found in fruits of CF or CS extracts do not play a significant role in inhibiting digestive enzymes but exert antioxidant activity.
Project description:Diabetes mellitus is a multifactorial metabolic disease characterized by post-prandial hyperglycemia (PPHG). ?-amylase and ?-glucosidase inhibitors aim to explore novel therapeutic agents. Herein we report the promises of Dioscorea bulbifera and its bioactive principle, diosgenin as novel ?-amylase and ?-glucosidase inhibitor. Among petroleum ether, ethyl acetate, methanol and 70% ethanol (v/v) extracts of bulbs of D. bulbifera, ethyl acetate extract showed highest inhibition upto 72.06 ± 0.51% and 82.64 ± 2.32% against ?-amylase and ?-glucosidase respectively. GC-TOF-MS analysis of ethyl acetate extract indicated presence of high diosgenin content. Diosgenin was isolated and identified by FTIR, 1H NMR and 13C NMR and confirmed by HPLC which showed an ?-amylase and ?-glucosidase inhibition upto 70.94 ± 1.24% and 81.71 ± 3.39%, respectively. Kinetic studies confirmed the uncompetitive mode of binding of diosgenin to ?-amylase indicated by lowering of both Km and Vm. Interaction studies revealed the quenching of intrinsic fluorescence of ?-amylase in presence of diosgenin. Similarly, circular dichroism spectrometry showed diminished negative humped peaks at 208 nm and 222 nm. Molecular docking indicated hydrogen bonding between carboxyl group of Asp300, while hydrophobic interactions between Tyr62, Trp58, Trp59, Val163, His305 and Gln63 residues of ?-amylase. Diosgenin interacted with two catalytic residues (Asp352 and Glu411) from ?-glucosidase. This is the first report of its kind that provides an intense scientific rationale for use of diosgenin as novel drug candidate for type II diabetes mellitus.
Project description:BACKGROUND: Albizzia Lebbeck Benth. is traditionally important plant and is reported to possess a variety of pharmacological actions. The present research exertion was undertaken to isolate and characterized the flavonoids from the extract of stem bark of Albizzia Lebbeck Benth. and to evaluate the efficacy of the isolated flavonoids on in-vitro models of type-II diabetes. Furthermore, the results of in-vitro experimentation inveterate by the molecular docking studies of the isolated flavonoids on ?-glucosidase and ?-amylase enzymes. METHODS: Isolation of the flavonoids from the methanolic extract of stem bark of A. Lebbeck Benth was executed by the Silica gel (Si) column chromatography to yield different fractions. These fractions were then subjected to purification to obtain three important flavonoids. The isolated flavonoids were then structurally elucidated with the assist of 1H-NMR, 13C-NMR, and Mass spectroscopy. In-vitro experimentation was performed with evaluation of ?-glucosidase, ?-amylase and DPPH inhibition capacity. Molecular docking study was performed with GLIDE docking software. RESULTS: Three flavonoids, (1) 5-deoxyflavone (geraldone), (2) luteolin and (3) Isookanin were isolated from the EtOAc fraction of the methanolic extract of Albizzia lebbeck Benth bark. (ALD). All the compounds revealed to inhibit the ?-glucosidase and ?-amylase enzymes in in-vitro investigation correlating to reduce the plasma glucose level. Molecular docking study radically corroborates the binding affinity and inhibition of ?-glucosidase and ?-amylase enzymes. CONCLUSION: The present research exertion demonstrates the anti-diabetic and antioxidant activity of the important isolated flavonoids with inhibition of ?-glucosidase, ?-amylase and DPPH which is further supported by molecular docking analysis.
Project description:Butea monosperma is one of the extensively used plants in traditional system of medicines for many therapeutic purposes. In this study, the antioxidant activity, ?-glucosidase and ?-amylase inhibition properties of freeze drying assisted ultrasonicated leaf extracts (hydro-ethanolic) of B. monosperma have been investigated. The findings revealed that 60% ethanolic fraction exhibited high phenolic contents, total flavonoid contents, highest antioxidant activity, and promising ?-glucosidase and ?-amylase inhibitions. The UHPLC-QTOF-MS/MS analysis indicated the presence of notable metabolites of significant medicinal potential including apigenin, apigenin C-hexoside C-pentoside, apigenin C-hexoside C-hexoside, apigenin-6,8-di-C-pentoside and genistin etc., in B. monosperma leave extract. Docking studies were carried out to determine the possible role of each phytochemical present in leaf extract. Binding affinity data and interaction pattern of all the possible phytochemicals in leaf extract of B. monosperma revealed that they can inhibit ?-amylase and ?-glucosidase synergistically to prevent hyperglycemia.
Project description:Context: Paederia foetida L. (Rubiaceae) is an edible plant distributed in Asian countries including Malaysia. Fresh leaves have been traditionally used as a remedy for indigestion and diarrhea. Several phytochemical studies of the leaves have been documented, but there are few reports on twigs. Objective: This study investigates the enzyme inhibition of P. foetida twig extracts and compound isolated from them. In addition, in silico molecular docking of scopoletin was investigated. Materials and methods: Plants were obtained from two locations in Malaysia, Johor (PFJ) and Pahang (PFP). Hexane, chloroform and methanol extracts along with isolated compound (scopoletin) were evaluated for their enzyme inhibition activities (10,000-0.000016 µg/mL). The separation and identification of bio-active compounds were carried out using column chromatography and spectroscopic techniques, respectively. In silico molecular docking of scopoletin with receptors (α-amylase and α-glucosidase) was carried out using AutoDock 4.2. Results: The IC50 values of α-amylase and α-glucosidase inhibition activity of PFJ chloroform extract were 9.60 and 245.6 µg/mL, respectively. PFP chloroform extract exhibited α-amylase and α-glucosidase inhibition activity (IC50 = 14.83 and 257.2 µg/mL, respectively). The α-amylase and α-glucosidase inhibitory activity of scopoletin from both locations had IC50 values of 0.052 and 0.057 µM, respectively. Discussion and conclusions: Separation of PFJ chloroform extract afforded scopoletin (1), stigmasterol (2) and γ-sitosterol (3) and the PFP chloroform extract yielded (1), (2), (3) and ergost-5-en-3-ol (4). Scopoletin was isolated from this species for the first time. In silico calculations gave a binding energy between scopoletin and α-amylase of -6.03 kcal/mol.
Project description:As part of an ongoing search for new natural products from medicinal plants to treat type 2 diabetes, two new compounds, a megastigmane sesquiterpenoid sulfonic acid (1) and a new cyclohexylethanoid derivative (2), and seven related known compounds (3-9) were isolated from the leaves of Wedelia chinensis (Osbeck.) Merr. The structures of the compounds were conducted via interpretation of their spectroscopic data (1D and 2D NMR, IR, and MS), and the absolute configurations of compound 1 were determined by the modified Mosher's method. The MeOH extract of W. chinensis was found to inhibit ?-amylase and ?-glucosidase inhibitory activities as well as by the compounds isolated from this extract. Furthermore, compound 7 showed the strongest effect with IC50 values of 112.8?±?15.1??g/mL (against ?-amylase) and 785.9?±?12.7??g/mL (against ?-glucosidase). Compounds 1, 8, and 9 showed moderate ?-amylase and ?-glucosidase inhibitory effects. Other compounds showed weak or did not show any effect on both enzymes. The results suggested that the antidiabetic properties from the leaves of W. chinensis are not simply a result of each isolated compound but are due to other components such as the accessibility of polyphenolic groups to ?-amylase and ?-glucosidase activities.
Project description:Cissus polyantha (Vitaceae) is a plant used in Cameroonian traditional medicine for the treatment of diabetes. The aims of this study were to evaluate the in vitro antioxidant and antidiabetic activities of the aqueous extract of Cissus polyantha leafy stems. The enzyme inhibitory activity was determined in vitro on ?-amylase and ?-glucosidase enzymes, followed by confirmative study in vivo on normal rats (oral starch and sucrose tolerance tests at doses of 111, 222, and 444?mg/kg). The ferric reducing antioxidant power and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) antiradical activity of the extract were examined to evaluate the antioxidant potential of the extract. The total content of phenols, flavonoids, and tannins of the extract were also determined. The results showed an inhibitory effect of the extract on the ?-amylase and ?-glucosidase activities with IC50 values of 216.14 and 182.40??g/mL, respectively. The extract at doses of 222 and 444?mg/kg induced a significant decrease in postprandial glycaemia during the starch and sucrose tolerance tests. A remarkable antiradical activity of the extract was obtained although lower than that of the standard product. The aqueous extract of leafy stems of Cissus polyantha has an interesting inhibitory activity on the ?-amylase and ?-glucosidase enzymes, as well as an antioxidant potential, thus validating its use in traditional medicine for the treatment of diabetes mellitus and its complications.
Project description:Regulating activities of ?-amylase and ?-glucosidase through the use of specific inhibitors is a main strategy for controlling type 2 diabetes. Smilax aristolochiifolia root decoctions are traditionally used in Mexico as hypoglycemic and for weight loss, but the active principles and mechanisms underlying such putative metabolic effects are yet unknown. Here, we isolated the major bioactive compounds from a hydroethanolic extract of S. aristolochiifolia root by fast centrifugal partition chromatography and evaluated their effects against pancreatic ?-amylase and yeast ?-glucosidase. A chlorogenic acid-rich fraction (CAF) inhibited ?-amylase activity with an IC50 value of 59.28??g/mL in an uncompetitive manner and ?-glucosidase activity with an IC50 value of 9.27??g/mL in a noncompetitive mode. Also, an astilbin-rich fraction (ABF) inhibited ?-glucosidase activity with an IC50 value of 12.30??g/mL, in a noncompetitive manner. CAF inhibition ?-amylase was as active as acarbose while both CAF and ABF were 50-fold more potent inhibitors of ?-glucosidase than acarbose. The molecular docking results of chlorogenic acid and astilbin with ?-amylase and ?-glucosidase enzymes correlated with the inhibition mechanisms suggested by enzymatic assays. Our results prove that S. aristolochiifolia roots contain chlorogenic acid and astilbin, which inhibit carbohydrates-hydrolyzing enzymes, suggesting a new mechanism for the hypoglycemic effect reported for this plant.
Project description:This study aims at investigating the contribution of two classes of compounds, flavonoids and iridoids, to the bioactivity of Arbutus unedo L. leaves and fruits. The impact of different extraction procedures on phytochemicals content and hypoglycemic, antioxidant, and nitric oxide (NO) inhibitory activities of A. unedo fresh and dried plant materials was investigated. Ellagic acid 4-O-?-D-glucopyranoside, kaempferol 3-O-glucoside, and norbergenin were identified for the first time in this genus by using liquid chromatography-electrospray ionization-quadrupole-time of flight-mass spectrometry (LC-ESI-QTOF-MS). Three iridoids (gardenoside, geniposide, unedoside) are specifically identified in the leaves. Interestingly, asperuloside was extracted only from dried fruits by ethanol with Soxhlet apparatus. Extracts were screened for their potential antioxidant activities by using the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Activity Power (FRAP), and ?-carotene bleaching tests. Based on the Global Antioxidant Score (GAS) calculation, the most promising antioxidant extract was obtained by hydroalcoholic maceration of dried leaves that showed half maximal inhibitory concentration (IC50) of 0.42 and 0.98 ?g/mL in ABTS and DPPH assays, respectively. The hypoglycaemic activity was investigated by ?-amylase and ?-glucosidase inhibition tests. Extracts obtained by ethanol ultrasound extraction of fresh leaves and hydroalcoholic maceration of fresh fruits (IC50 of 19.56 and 28.42 ?g/mL, respectively) are more active against ?-glucosidase than the positive control acarbose (IC50 of 35.50 ?g/mL). Fruit extracts exhibited the highest anti-inflammatory activity.
Project description:Hyperglycemia is the hallmark of type 2 diabetes mellitus, and its prevention will go a long way in managing the disease and its associated complications. Reduction of postprandial hyperglycemia through retarding carbohydrates digesting enzymes is one of the major therapeutic approaches used in the management of diabetes.The aim of the present study was to investigate the antidiabetic and cytotoxic effects of Cissus cornifolia extracts in vitro.The α-amylase and α-glucosidase inhibitory activities of ethanolic and aqueous extracts of C. cornifolia root and leaves were investigated when the cytotoxic effects of these extracts were analyzed using MTT assay on human embryonic kidney (HEK 293) cell lines.The root ethanolic extract showed a mild α-amylase inhibitory activity with IC50 value of 22.75 ± 1.23 μg/ml, but strong α-glucosidase inhibitory activity with IC50 value 2.81 ± 0.97 μg/ml and the aqueous root extract indicated moderate inhibition for both α-amylase and α-glucosidase with IC50 values of 33.70 ± 3.75 and 37.48 ± 2.35 μg/ml, respectively. The ethanolic root extract was found nontoxic at tested concentrations on HEK 293 cell lines as confirmed by the MTT assay with 93% cell viability at the highest concentration (200 μg/ml) tested. However, the aqueous extracts (leaf and root) were found cytotoxic at concentrations above 50 μg/ml.Data of this study suggest that the root ethanolic extracts of C. cornifolia possesses moderate α-amylase, but strong α-glucosidase inhibitory activity in vitro and did not show significant cytotoxicity with the tested concentrations.Present study was conducted to examine effects of antidiabetic and cyctotoxic effects of Cissus conrnifolia root and leaves extracts in vitro. Data of this study suggest that the root ethanolic extract of C. cornifolia possesses mild to moderated antidiabetic activity via inhibiting carbohydrate digesting enzymes when no significant toxicity was observed with tested concentrations. Abbreviations used: alex: Aqueous leaf extract; arex: Aqueous root extract; CC: Cissus cornifolia; DNS: Dinitrosalicylic acid; DMSO: Dimethylsulfoxide; elex: Ethanolic leaf extract; erex: Ethanolic root extract; IDF: International Diabetes Federation; MEM: Minimum essential medium; NIDDM: Noninsulin-dependent diabetes mellitus; pNPG: Para-nitrophenyl glucopyranoside; SD: Standard deviation; T2D: Type 2 diabetes.