• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.601-608
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• 1997

In order to search for the way to utilize rice hull as a renewable resource, the inhibition on ${\alpha}-glucosidase$ and the fractionation of rice hull extract was investigated. An ethanol extract of rice hull from Japonica-type rice seeds exhibited 30% inhibitory activity on rat intestinal brush border ${\alpha}-glucosidase$ (1.4 mU/mL) in vitro at the concentration of 0.8 mg/mL using 6 mM p-nitrophenyl ${\alpha}-D-glucopyranoside$ as a substrate $(IC_{50}\;162\;mg/mL)$. Among the fractions obtained by partitioning the ethanol extract successively with solvents, the ethyl acetate fraction at the concentration of 0.8 mg/mL was found to exhibit the most potent inhibitory activity i.e. 65% inhibition of ${\alpha}-glucosidase\;(IC_{50}\;0.14\;mg/mL)$. Silica gel column chromatography of the ethyl acetate fraction exhibited slightly higher (90%) inhibitory activity, and its subsequent fractionation by Sephadex LH-20 column chromatography did not improve inhibitory activity. Considering the inhibitory activity and yield, the ethyl acetate fraction obtained by the solvent-partitioning process would be a candidate for the hypoglycemic food if it has in vivo effectiveness.

• Journal of Pharmacopuncture
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• v.22 no.2
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• pp.115-121
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• 2019

Objectives: The objective of this study was to evaluate antidiabetic activity of Chaturmukha rasa based on streptozotocin induced diabetes model, alpha amylase inhibitory activity, alpha Glucosidase inhibitory activity and inhibition of sucrase. Methods: Chaturmukha rasa was prepared as per Ayurvedic formulary. Antidiabetic activity was measured in experimentally streptozotocin induced rats. The dose was taken as 45 mg/kg, i.p. The antidiabetic activity of Chaturmukha rasa was compared Triphala Kwatha, a marketed formulation. Further In vitro $\acute{\alpha}$- Amylase Inhibitory Assay, In vitro salivary amylase Inhibitory Assay, In vitro ${\alpha}-Glucosidase$ Inhibitory Assay and In vitro Sucrase Inhibitory Assay was performed with respect to Chaturmukha rasa. The IC50 value was calculated for all the above activity. Results: Streptozotocin with Acarbose showed significant decrease in blood glucose level whereas streptozotocin with Triphala kwatha showed more decrease in blood glucose level than Streptozotocin with Acarbose. The combination of Streptozotocin + Triphala kwatha + Chaturmukha rasa showed a significant decrease in blood glucose level on 21st day. In vitro $\acute{\alpha}$- Amylase Inhibitory Assay the Chaturmukha rasa showed IC50 value $495.94{\mu}l$ when compared with Acarbose $427.33{\mu}l$, respectively. In the ${\alpha}-Glucosidase$ Inhibitory Assay Chaturmukha rasa showed IC50 value $70.93{\mu}l$ when compared with Acarbose $102.28{\mu}l$, respectively. In vitro Sucrase Inhibitory Assay Chaturmukha rasa showed IC50 value $415.4{\mu}l$ when compared with Acarbose $371.43{\mu}l$, respectively. Conclusion: This study supports that Chaturmukha rasa may inhibit diabetes by inhibition of salivary amylase or alpha Glucosidase or sucrase. This may be the mechanism by which Chaturmukha rasa inhibits diabetes. Further this study supports the usage of Chaturmukha rasa for the management of diabetes.

• Journal of Nutrition and Health
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• v.46 no.4
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• pp.315-323
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• 2013

This study was conducted in order to compare the biological activities of leaf and root water extracts of Smilax china L. (SC) by measuring the total polyphenol and flavonoid contents, anti-oxidant activity, inhibitory effect on ${\alpha}$-glucosidase, and anti-inflammatory gene expression. The total polyphenol and flavonoid contents of SC leaf (SCLE) and root (SCRE) water extracts were 127.93 mg GAE/g and 39.50 mg GAE/g and 41.99 mg QE/g and 1.25 mg QE/g, respectively. The anti-oxidative activities of SCLE and SCRE were measured using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity assay and reducing power assay. Both SCLE and SCRE scavenged radicals in a concentration-dependent manner, and SCLE showed stronger radical scavenging activity and reducing power than SCRE; however, both SCLE and SCRE exhibited lower activities than ascorbic acid. Compared to the anti-diabetic drug acarbose, which was used as a positive control, SCLE and SCRE exhibited low ${\alpha}$-glucosidase inhibition activities; nevertheless, the activity of SCLE was 3.7 fold higher than that of SCRE. Finally, SCLE caused significantly decreased expression of the LPS-induced cytokines, iNOS, and COX-2 mRNA in RAW264.7 cells, indicating anti-inflammatory activity. These results indicate that SCLE might be a potential candidate as an anti-oxidant, anti-diabetic, and anti-inflammatory agent.

• Journal of Applied Biological Chemistry
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• v.50 no.2
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• pp.70-73
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• 2007

Antioxidant and anti-diabetic activities of acorn were evaluated by its potential for scavenging stable DPPH free radical, inhibition of lipid peroxidation, reducing power, and inhibiton of ${\alpha}-glucosidase\;and\;{\alpha}-amylase$. The water extract of acorn exhibited strong antioxidant and antidiabetic related activities in the tested model systems. Solvent fractionation of the water extract revealed that the water fraction and the EtOAc fraction had strong antioxidant activity, and inhibitory activity on ${\alpha}-glucosidase\;and\;{\alpha}-amylase$. The water fraction exhibited higher DPPH radical scavenging activity ($EC_{50}=7.19{\mu}g/mL$) than that of ${\alpha}-tocopherol\;(EC_{50}=7.59{\mu}g/mL)$. It is considered that water extract of acorn has the potential for natural antioxidant and anti-diabetic products.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.164-169
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• 2015

This study evaluated in vitro antioxidant activity, antioxidant content, and ${\alpha}$-glucosidase and pancreatic lipase inhibitory activities of ethanol extracts of samnamul (shoot of Aruncus dioicus), miyeokchwi (Solidago virgaurea), daraesoon (shoot of Actinidia arguta Planchon), and bangpungnamul (leaves of Ledebouriella seseloides), as muknamul, and fresh chamnamul (Pimpinella brachycarpa). Tocopherol content (4.8-78.3 mg/100 g) of sanchae was lower than polyphenols (4.4-12.2 g/100 g). Daraesoon with high tocopherol contents showed high antioxidant activity and ${\alpha}$-glucosidase and pancreatic lipase inhibitory activities. Samnamul had the highest levels of polyphenols and flavonoids, the highest antioxidant activity, and ${\alpha}$-glucosidase inhibition. Antioxidant activity was correlated with flavonoid content ($r^2=0.8895$), but was not correlated with the levels of other antioxidants tested, suggesting that polyphenol content in samnamul, miyeokchwi, daraesoon, bangpung, and chamnamul might not be critical determinant of antioxidant activity. Our results strongly suggest that samnamul and daraesoon could be useful in the treatment of diabetes and obesity.

• Korean Journal of Oriental Medicine
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• v.10 no.1
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• pp.119-126
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• 2004

For the purpose of developing new anti-HIV agents from natural sources, the extracts of Solanum nigrum L. were tested for their inhibitory effects on HIV-1 replication and its essential enzymes as the reverse transcriptase (RT), protease and ${\alpha}$-glucosidase. In the assay of HIV-1-infected human T-cell line, water extracts inhibited the HIV- 1 -induced cytopathic effects with IC (inhibitory concentration) of 100 ug/ml. Moreover water extracts (100ug/ml) of aerial parts showed strong activity of 32.6% on anti-HIV-1 PR using the activity of the enzyme to cleave an oligopeptide. In the HIV-1 reverse transcriptase inhibition assay, aqueous extract a inhibited 17.4%, but no glucosidase inhibitory activities. We found out this result, for these samples it is possible that the inhibition of the viral replication in vitro is due to the inhibition at least one of PR and RT. It would be of great interest to identify the compounds which are responsible for this inhibition, since all therapeutically useful agent up to date are PR, RT and ${\alpha}$-glucosidase inhibitors.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.246-252
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• 2012

After a mixed carbohydrate diet, inhibition of ${\alpha}$-amylase and ${\alpha}$-glucosidase involved in the digestion and absorption of carbohydrates can significantly decrease the postprandial increase of blood glucose level. In the course of screening these useful enzyme inhibitors, we selected five kinds of bean, using an in-vitro enzyme inhibition assay method. To evaluate the effect of germination process on the functionality of the bean, we investigated the inhibitory activities of the water extracts of non-germinated bean and germinated bean against ${\alpha}$-amylase and ${\alpha}$-glucosidase, relevant to postprandial hyperglycemia. We also investigated the oxygen radical absorbance capacity(ORAC), total phenolics content, and postprandial blood glucose lowering effect in rats(Sprague-Dawley rat model). Most germinated beans showed significantly higher ${\alpha}$-glucosidase inhibitory activity, compared with non-germinated beans. Among germinated beans, Glycine max had the highest ${\alpha}$-glucosidase inhibitory activity(53.3%). The water extract of germinated Phaseolus vulgaris L. had the highest ${\alpha}$-amylase inhibitory activity(95.1%), followed by Glycine max(58.7%), and Glycine max L. Merr(54.1%). Furthermore, the five germinated beans also showed high antioxidant activities in ORAC assay. Results suggested that the germination process may improve and enhance the anti-hyperglycemia potential and antioxidant activity of the bean.

• Food Science and Preservation
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• v.23 no.2
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• pp.239-245
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• 2016

This study was conducted to compare the functionality (antioxidant, anti-diabetic, and anti-dementia activities) of the methanol extract of Allium hookeri root grown in Korea (KR) and Myanmar (MR). The total polyphenol and flavonoid contents of KR and MR were 5.27 and 4.80 mg GAE/g, and 0.35 and 0.24 mg QE/g, respectively. KR contained significantly higher levels of total polyphenols and total flavonoids than those of MR (p<0.05). The IC50 values of KR and MR were 6.53 and 5.31 mg/mL, respectively, for DPPH radical scavenging activity. However, KR had a significantly higher ABTS radical scavenging activity, $Fe^{2+}$ chelating ability, and reducing power compared with those of MR (p<0.05). In the evaluation of anti-diabetic activity, KR showed significantly higher ${\alpha}-glucosidase$ inhibition activity than acarbose and MR at whole concentrations (p<0.05). KR and MR had acetylcholinesterase inhibition activities that of 51.44% and 44.33%, respectively, at a 50 mg/mL concentration. These results suggested that roots of A. hookeri, especially KR, could be useful in improving diabetic and dementia disorders due to their high antioxidant, anti-diabetic, and anti-dementia activities.

• Microbiology and Biotechnology Letters
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• v.38 no.2
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• pp.183-189
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• 2010

In the course of screening for anti-acidosis and anti-diabetes agent from natural products, the inhibitory activities of Nepales plant extracts against microbial $\alpha$-amylase and $\alpha$-glucosidase were evaluated. Among the 100 different kinds of ethanol extracts, Cedrus deodara (Roxb.) G. Don and Myrica nagi Thunb showed strong inhibition activities against $\alpha$-amylase. The $IC_{50}$ values of C. deodara (Roxb.) G. Don, M. nagi Thunb and acarose, a commercial available anti-diabetes agent, were 44.5, 47.5 and $50.5\;{\mu}g/mL$, respectively. Considering the crude extract of C. deodara (Roxb.) G. Don, and M. nagi Thunb, these extracts have strong potentials as anti-acidosis or anti-diabates agent. In a while, Cleistocalyx operculatus (Roxb.) extract showed a good inhibition activity to $\alpha$-amylase and $\alpha$-glucosidase, even it was recently reported. The selected three extracts did not show any hemolysis activity against human red blood cell up to 1 mg/mL, and the inhibition activities were maintained by heat or acid treatment. Moreover, treatment of HCl (0.01N) for 1 h into C. operculatus (Roxb.) and M. nagi Thunb increased the inhibition activity from 50% to 70%. Our results suggest that C. deodara (Roxb.) G. Don, M. nagi Thunb, and C. operculatus (Roxb.) are potential as anti-acidosis and anti-diabetes agents.

• Journal of Applied Biological Chemistry
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• v.51 no.3
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• pp.111-116
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• 2008

Aralia elata seeds were successively extracted with water, methanol, ethanol, acetone and chloroform. The crude extracts were investigated for antioxidant and antidiabetic activities. The antioxidant properties of various extracts were evaluated by antioxidant tests, such as DPPH free radical-scavenging activity, hydroxyl radical-scavenging assay, metal-chelating activity, lipid peroxidation inhibition activity and reducing power assay. The 70% methanol extract exhibited the highest activity in the in vitro models of DPPH free radical-scavenging activity, metal-chelating activity, and reducing power assay. Acetone extract showed good effects on lipid peroxidation inhibition and hydroxyl radical-scavenging assay at a low concentration. In addition, the $\alpha$-glucosidase inhibition assay showed that 70% methanol extract had the highest activity. These results indicate the high possibility of using A. elata seeds for medical application due to their efficient antioxidant properties.