Effect of Natural Products on Some Glycosidases and Their Expected Hypoglycemic Potential (original) (raw)

Glucosidase and -amylase inhibitory effect and antioxidant activity of ten plant extracts traditionally used in Iran for diabetes

Journal of Medicinal Plants Research, 2013

In the present study various extracts of ten medicinal plants, collected in Iran, were examined for αglucosidase and α-amylase inhibition using an in vitro model. Also total phenol content and antioxidant activity of the extracts were investigated. Various extracts of the plants (Cinnamomum zeylanicum, Crataegus oxyacantha, Hibiscus sabdariffa, Morus alba, Portulaca oleracea, Rubus fruticosus, Syzygium aromaticum, Teucrium polium, Trigonella foenum-graecum, and Vaccinium arctostaphylos) were prepared using n-hexane, dichloromethane, chloroform, ethyl acetate and methanol. Methanol, dichloromethane and n-hexane extracts of S. aromaticum exerted high in vitro inhibitory potential against α-glucosidase and α-amylase with IC 50 ranging from 0.3 to 1.1 and 36.2 to 41.9 µg/ml, respectively. The mentioned extracts possessed the highest total phenolic contents (139.8, 119.6 and 136.1 mg GAE/g of extract). The antioxidant activities of the extracts, measured in terms of IC 50 values were 2.2, 3.9 and 0.7 µg/ml, respectively. C. zeylanicum was another traditionally used medicinal plant, which its extracts exhibited high hypoglycaemic effect by inhibition of α-glucosidase and α-amylase (IC 50 ranged from 0.5 to 8.7 and 37.1 to 52.5 µg/ml, respectively). The obtained results support the traditionally use of a number of the analyzed species.

α-Glucosidase and α-amylase inhibitory effect and antioxidant activity of ten plant extracts traditionally used in Iran for diabetes

Journal of medicinal plant research

In the present study various extracts of ten medicinal plants, collected in Iran, were examined for α-glucosidase and α-amylase inhibition using an in vitro model. Also total phenol content and antioxidant activity of the extracts were investigated. Various extracts of the plants (Cinnamomum zeylanicum, Crataegus oxyacantha, Hibiscus sabdariffa, Morus alba, Portulaca oleracea, Rubus fruticosus, Syzygium aromaticum, Teucrium polium, Trigonella foenum-graecum, and Vaccinium arctostaphylos) were prepared using n-hexane, dichloromethane, chloroform, ethyl acetate and methanol. Methanol, dichloromethane and n-hexane extracts of S. aromaticum exerted high in vitro inhibitory potential against α-glucosidase and α-amylase with ranging from 0.3 to 1.1 and 36.2 to 41.9 µg/ml, respectively. The mentioned extracts possessed the highest total phenolic contents (139.8, 119.6 and 136.1 mg GAE/g of extract). The antioxidant activities of the extracts, measured in terms of IC50 values were 2.2, 3.9 ...

Antidiabetic Indian plants: a good source of potent amylase inhibitors

Evidence-Based …, 2008

Diabetes is known as a multifactorial disease. The treatment of diabetes (Type II) is complicated due to the inherent pathophysiological factors related to this disease. One of the complications of diabetes is post-prandial hyperglycemia (PPHG). Glucosidase inhibitors, particularly α-amylase inhibitors are a class of compounds that helps in managing PPHG. Six ethnobotanically known plants having antidiabetic property namely, Azadirachta indica Adr. Juss.; Murraya koenigii (L.) Sprengel; Ocimum tenuflorum (L.) (syn: Sanctum); Syzygium cumini (L.) Skeels (syn: Eugenia jambolana); Linum usitatissimum (L.) and Bougainvillea spectabilis were tested for their ability to inhibit glucosidase activity. The chloroform, methanol and aqueous extracts were prepared sequentially from either leaves or seeds of these plants. It was observed that the chloroform extract of O. tenuflorum; B. spectabilis; M. koenigii and S. cumini have significant α-amylase inhibitory property. Plants extracts were further tested against murine pancreatic, liver and small intestinal crude enzyme preparations for glucosidase inhibitory activity. The three extracts of O. tenuflorum and chloroform extract of M. koenigi showed good inhibition of murine pancreatic and intestinal glucosidases as compared with acarbose, a known glucosidase inhibitor.

Natural products as alpha-amylase and alpha-glucosidase inhibitors and their hypoglycaemic potential in the treatment of diabetes: an update

Mini Reviews in Medicinal Chemistry, 2010

The inhibition of alpha-glucosidase and alpha-amylase, enzymes involved in the digestion of carbohydrates, can significantly reduce the post-prandial increase of blood glucose and therefore can be an important strategy in the management of blood glucose level in type 2 diabetic and borderline patients. Currently, there is renewed interest in plant-based medicines and functional foods modulating physiological effects in the prevention and cure of diabetes and obesity. The plant kingdom is a wide field to search for natural effective oral hypoglycaemic agents that have slight or no side effects. More than ca. 1200 plant species have been recorded to be used empirically worldwide for their alleged hypoglycaemic activity. Therefore, natural alpha-glucosidase and alpha-amylase inhibitors from plant sources offer an attractive strategy for the control of hyperglycaemia. This article reviews recent data on plant extracts and isolated natural compounds that are being tested for their hypglycaemic activity, highlights ongoing research and considers the future persepctives.

Traditional Medicinal Herbs and Food Plants Have the Potential to Inhibit Key Carbohydrate Hydrolyzing Enzymes In Vitro and Reduce Postprandial Blood Glucose Peaks In Vivo

The Scientific World Journal, 2012

We hypothesized that some medicinal herbs and food plants commonly used in the management of diabetes can reduce glucose peaks by inhibiting key carbohydrate hydrolyzing enzymes. To this effect, extracts ofAntidesma madagascariense(AM),Erythroxylum macrocarpum(EM),Pittosporum senacia(PS), andFaujasiopsis flexuosa(FF),Momordica charantia(MC), andOcimum tenuiflorum(OT) were evaluated for α-amylase and α-glucosidase inhibitory effects based on starch-iodine colour changes and PNP-G as substrate, respectively. Only FF and AM extracts/fractions were found to inhibit α-amylase activity significantly (P<0.05) and coparable to the drug acarbose. Amylase bioassay on isolated mouse plasma confirmed the inhibitory potential of AM and FF extracts with the ethyl acetate fraction of FF being more potent (P<0.05) than acarbose. Extracts/fractions of AM and MC were found to inhibit significantly (P<0.05) α-glucosidase activity, with IC50comparable to the drug 1-deoxynojirimycin.In vivostud...

Potent Natural Inhibitors of Alpha-Glucosidase and Alpha-Amylase against Hyperglycemia in Vitro and in Vivo

2017

The inhibition of alpha-glucosidase and alpha-amylase is one of clinic strategies for remedy the type II diabetes. Herbal medicines are reported to alleviate hyperglycemia. However, the constituents from those sources whether are targeted to the alpha-glucosidase and alpha-amylase still unexplored. This study attempted to select the compounds for efficacy of hypoglycemia via cellular and mouse levels. The results illustrated that the cytotoxicity in all tested compounds at various concentrations except the concentration of 16-hydroxy-cleroda-3,13-dine-16,15-olide (HCD) at 30 µM were not significant difference (p > 0.05) when compared with the untreated control. Acarbose (reference drug), Antroquinonol, Catechin, Quercetin, Actinodaphnine, Curcumin, HCD, Docosanol, Tetracosanol, Berberine, and Rutin could effectively inhibit the alpha-glucosidase activity of Caco-2 cells when compared with the control (maltose). The compounds (Curcumin, HCD, Tetracosanol, Antroquinonol, Berberine,...

α-Glucosidase and α-Amylase Inhibitory Activity of Common Constituents from Traditional Chinese Medicine Used for Diabetes Mellitus

Chinese Journal of Natural Medicines, 2010

To screen α-glucosidase and α-amylase inhibitors from common natural products found in traditional Chinese medicines (TCM) usually used for diabetes mellitus clinically and try to illustrate scientific evidence of those TCMs for diabetes mellitus. METHOD: 43 common natural products in TCM for diabetes mellitus were used for assay for α-glucosidase and α-amylase inhibitory activities in vitro. RESULTS: More than 24 and 20 compounds showed obvious α-glucosidase and α-amylase inhibitory activities respectively. Among them, 10 compounds revealed strong inhibition on both α-glucosidase and α-amylase. CONCLUSION: More than 40% test compounds possess inhibitory activities on α-glucosidase and/or on α-amylase, partially interpreting the reasons for these TCMs against diabetes mellitus.

Twenty Traditional Algerian Plants Used in Diabetes Therapy as Strong Inhibitors of α-Amylase Activity

International Journal of Carbohydrate Chemistry, 2014

In the present work, we have studied the inhibitory effects of aqueous and alcoholic extracts of six Algerian medicinal plants known by their therapeutic virtues against diabetes. The total phenolic compounds content, assayed using Folin-Ciocalteu’s reagent, of the samples ranged from 0.183 mg/g to 43.088 mg/g and from 1.197 mg/g to 7.445 mg/g, expressed as gallic acid equivalent (GAE), for the, respectively, whereas the total flavonoids concentrations, detected using 2% of the aluminium chloride, ranged from 0.41 mg/g to 11.613 mg/g and from 0.0097 mg/g to 1.591 mg/g, expressed as rutin equivalents (RE), for the aqueous and methanolic extracts, respectively. The major plants were found to inhibit enzymatic activities of Aspergillus oryzae-amylase in a concentration dependent manner. The values of the inhibition constants (Ki) have been determined according to the Dixon and Lineweaver-Burk methods. The results showed that the Ki values were less than 55 ppm for the all extracts. A s...

EVALUATION OF SELECTED MEDICINAL HERBS FOR ANTIDIABETIC ACTIVITY VIA ALPHA-GLUCOSIDASE INHIBITION

Literature and native therapies have cited bitter melon, dandelion, blueberry, and roselle, as hypoglycemic agents, however, the exact mechanisms of action are unknown. It was hypothesized that, these agents could induce hypoglycemia, through the mechanism of α-glucosidase inhibition. The aim of the present study was, to examine inhibition of alpha-glucosidase as one of the possible mechanisms of action, of bitter melon (Mormodicacharantia), dandelion (Taraxacumofficinale), blueberry (Vacciniumcorybosum), and roselle (Hibiscus sabdariffa). Each of these agents has been used in the treatment of diabetes in, different parts of the world. The study was done in vitro, using α-glucosidase, obtained from Bacillus. The inhibitory effect of different concentrations of alcoholic extracts of the plants, on α-glucosidase was studied. The extracts of the plant showed inhibitory activities, against α-glucosidase, with IC50 values in a dose dependent manner. The result demonstrated that, bitter melon, roselle, dandelion, and blueberry share similar mechanism of action with Acarbose, which is being used as an antidiabetic agent.