• Korean Journal of Plant Resources
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• v.26 no.4
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• pp.411-416
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• 2013

This study was conducted not only to analyze ${\alpha}$-glucosidase inhibition activity with fronds and rhizomes of nine Pteridophyte species, but also to select the plant materials suitable for natural ${\alpha}$-glucosidase inhibitor. Harvested rhizomes and fronds were washed, freeze-dried and grinded. After conducting ultrasonification extraction for 30 minutes in ultrasonic water tank with 100% methanol solvent, and vacuum filtration, ${\alpha}$-glucosidase inhibition activity was measured. Acarbose was used as the positive control. After mixing $100{\mu}L$ of 0.7 unit ${\alpha}$-glucosidase enzyme solution into $50{\mu}L$ of extract and reacting them at $37^{\circ}C$ for 10 minutes, $50{\mu}L$ of 1.5 mM ${\rho}$-NPG solution was taken and reacted at $37^{\circ}C$ for 20 minutes. The reaction was stopped with 1 mL of 1 M $Na_2CO_3$ and absorbance was measured in 405 nm. With the regression analysis, the content of solubility solids (the value of $IC_{50}$) which can inhibit 50% of 0.7 unit ${\alpha}$-glucosidase solution's activity was investigated. The frond ($IC_{50}=14.00{\sim}913.33{\mu}g{\cdot}mL^{-1}$) and rhizome extracts ($IC_{50}=12.93{\sim}205.84{\mu}g{\cdot}mL^{-1}$) of nine Pteridophyte species showed higher ${\alpha}$-glucosidase inhibition activity in comparison with acarbose ($IC_{50}=1413.70{\mu}g{\cdot}mL^{-1}$). The extracts of fronds and rhizomes showed higher value than acarbose by 1.55~100.98 and 6.87~109.33 times each. Especially, ${\alpha}$-glucosidase inhibition activities of Pyrrosia lingua in fronds and Osmunda cinnamomea var. fokiensis in rhizomes were the highest. The necessary biomass of fronds and rhizomes for inhibiting 50% of ${\alpha}$-glucosidase activity showed the lowest value, 0.35, 0.27 mg each, in O. cinnamomea var. fokiensis. $IC_{50}$ value of P. lingua was the highest among fronds of nine Pteridophyte species, but content of soluble solids was 2.4 times less than O. cinnamomea var. fokiensis. So frond of O. cinnamomea var. fokiensis is more economic in comparison with P. lingua. As the result of this study, O. cinnamomea var. fokiensis showed high ${\alpha}$-glucosidase inhibition activity even with small biomass. Therefore it was considered to be high-valued economic material as natural ${\alpha}$-glucosidase inhibitor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.7
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• pp.993-999
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• 2015

For the purpose of investigating the in vitro antidiabetic activity of a medicinal herb and herb mixture extracts prepared through traditional antidiabetic prescription, this study examined ${\alpha}$-glucosidase inhibitory activity. Tyrosinase, a type I membrane glycoprotein, is synthesized and glycosylated in the endoplasmic reticulum (ER) and Golgi. The enzyme is subsequently transported to melanosomes, where it participates in melanogenesis. Previous studies showed that disruption of early ER N-glycan processing by an ${\alpha}$-glucosidase inhibitor suppresses tyrosinase enzymatic activity and melanogenesis. According to the results, most oriental medicinal herbal extracts were stronger than acarbose and N-butyldeoxynojirimycin, known as an ${\alpha}$-glucosidase inhibitor. Interestingly, ethyl acetate layer of enzyme hydrolyzed Cheongsimyeonjaeum had an inhibitory effect on melanin synthesis in B16F1 cells, although it did not inhibit tyrosinase activity directly. Together, ${\alpha}$-glucosidase inhibition activity could be used to evaluate anti-melanogenesis, although cross-checking with melanin inhibitory assay is recommended.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.22-28
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• 2014

In this study, we conducted the anti-HIV-1 enzymes assay in vitro and its active components were predicted by QSAR in silico for the elucidation of action mechanism on anti-HIV of natural resources. The extracts of Gardenia jasminoides var. radicans Makino were tested for their inhibitory effects on the reverse transcriptase (RT), protease and ${\alpha}$-glucosidase. In the enzyme inhibition assay, the methanol extracts of Gardenia jasminoides var. radicans Makino stem showed a strong activity of 32.5% on the enzyme activity to cleave an oligopeptide, resembling one of the cleavage sites in the viral polyprotein which can only be processed by HIV-1 protease. Moreover the methanol extracts of stem exhibited alpha-glucosidase inhibitory activities of 26.1%. The methanol extracts ($100{\mu}g/ml$) of stem showed a weak activity of 13.4% on anti-HIV-1 RT using Enzyme Linked Oligonucleotide Sorbent Assay (ELOSA) method. However, all extracts of leaf and stem didn't exhibit the HIV-1-induced cytopathic effects with IC (inhibitory concentration) of $100{\mu}g/ml$ in HIV-1-infected human T-cell line. From these results, it is suggested that Gardenia jasminoides var. radicans Makino extracts may possibly be involved in the inhibition of reverse transcriptase, protease and alpha-glucosidase but can't vitally concerned with the viral replication in vitro.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1243-1248
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• 2010

The physiological activities of Strychnos nux-vomica extracts were investigated through the total phenolic contents (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (RSA), comet assay, and $\alpha$-glucosidase inhibitory activity. S. nux-vomica extracts were prepared with methanol, ethanol, and acetone. The methanol extract showed the highest phenolic content (71 mg/100 g gallic acid equivalents). Pretreatment with S. nux-vomica extracts resulted in significant reductions in oxidative DNA damage at all of the concentrations tested ($1{\sim}50\;{\mu}g/mL$). The $\alpha$-glucosidase inhibitory activity of a methanol extract was 12.8% at the concentration of 1 mg/mL. Therefore, these results indicate that S. nux-vomica might be a noble potential candidate exhibiting antioxidant and $\alpha$-glucosidase inhibitory activity.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.857-863
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• 2010

This study was conducted to evaluate the antioxidant activity, Angiotensin I Converting Enzyme (ACE) inhibitory activity, ${\alpha}$-glucosidase inhibitory activity, nitrate synthesis inhibitory activity, and antiproliferation inhibitory effect on ethanol extract and its solvent fractions of $Coreopsis$ $tinctoria$ Nutt. Ethyl acetate fraction was the strongest at 1,1-diphenyl-2-picryl hydrazyl (DPPH) ($IC_{50}=0.100mg{\cdot}mL^{-1}$) and 2,2'-Azino-bis-(3-ethylbenozothiazoline-6-sulfonic acid) (ABTS) (15.785 mg AA $eq{\cdot}10mg^{-1}$) radical scavenging activity, ACE (40.96% at $1mg{\cdot}mL^{-1}$), and ${\alpha}$-glucosidase ($IC_{50}=0.125mg{\cdot}mL^{-1}$) inhibitory effect among the solvent fractions. Nitrate synthesis inhibitory activity of ethanol extract, chloroform fraction, and ethyl acetate fraction effectively inhibited NO formation in a dose-dependent manner without the cytotoxic effect. Ethanol extract and its solvent fractions inhibited growth of HCT-116 colon cancer cells in a dose-dependent manner. n-Hexane fraction showed the highest antiproliferation inhibitory effect of $0.041mg{\cdot}mL^{-1}$ among fractions.

• Food Science and Preservation
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• v.21 no.4
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• pp.460-467
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• 2014

This study was conducted to investigate the effect of the addition of Hizikia fusiforme, Capsosiphon fulvescens, and Undaria pinnatifida sporophyll on the antioxidant and inhibitory potentials against key enzymes related to type 2 diabetes of a commercial vegetable extract. The nutritional quality and mineral concentration of a vegetable extract with seaweeds added were also analyzed. The addition levels of seaweed did not influence the proximate composition, whereas the calcium, sodium, potassium, magnesium, and iron concentrations significantly increased at the 5% Hizikia fusiforme and Undaria pinnatifida sporophyll addition levels. The 20% Hizikia fusiforme addition level significantly increased the total phenolic content and reducing power by 47.08% and 16.82%. The hydroxyl radical scavenging ability of the vegetable extract was not strengthened with the addition of seaweeds. The DPPH radical scavenging activity at the 20% Hizikia fusiforme, Capsosiphon fulvescens, and Undaria pinnatifida sporophyll addition levels significantly increased by 27.47%, 22.25%, and 17.27%, respectively. The vegetable extract with seaweeds added showed higher-level ${\alpha}$-glucosidase inhibition activities, accompanied by relatively weaker ${\alpha}$-amylase inhibition activity. In particular, at the 5% Undaria pinnatifida sporophyll addition level, the ${\alpha}$-glucosidase activity was significantly inhibited by 98.26%. Overall, the results showed that the incorporation of seaweeds into a vegetable extract effectively increased the mineral concentration and improved the antioxidant and inhibitory abilities of the extract on key enzymes linked to type 2 diabetes.

• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.208-213
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• 2016

This study evaluated the in vitro radical scavenging and ${\alpha}$-glucosidase inhibitory activities of dried daraesoon (shoot of hardy kiwi) during cooking involving rehydration and subsequent heating at $180^{\circ}C$ with or without perilla oil. Pigments and antioxidants were quantified by HPLC and spectrophotometry. Unlike the tocopherol content, the polyphenol, flavonoid, chlorophyll, and carotenoid contents as well as the DPPH radical scavenging and ${\alpha}$-glucosidase inhibitory activities of daraesoon extract were significantly decreased by rehydration (p<0.05). Heating the rehydrated daraesoon for 10 or 20 min increased its radical scavenging activity irrespective of perilla oil addition, whereas the ${\alpha}$-glucosidase inhibitory activity increased significantly only after heating with perilla oil (p<0.05). During cooking, changes in both activities showed a similar pattern to that showed by polyphenol content changes. These results suggest that the health functionality of daraesoon can be enhanced by an appropriate cooking process that retains polyphenols.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.558-561
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• 2008

Culture broth of Bacillus subtilis Y3-7 in tryptic soy broth (TSB) isolated from Korean traditional fermented food was evaluated for the inhibition of $\alpha$-glucosidase. The results of in vitro studies using the yeast $\alpha$-glucosidase demonstrated that the culture broth exerted inhibitory effects on $\alpha$-glucosidase with $IC_{50}$ value of 1.62 mg/mL, and functioned as a competitive inhibitor. Furthermore, the culture broth of B. subtilis Y3-7 significantly improved glucose tolerance in normal and streptozotocin-induced diabetic mice. The blood glucose levels in the mice receiving sucrose supplementation in the culture broth (1 g/kg, 2 g/kg) were measured at 48.7%, which corresponded to 22.2% of the levels measured in the control mice. These results indicated that the culture broth of B. subtilis Y3-7 in TSB might be considered as a useful compound for the preparation of functional foods for diabetic patients.

• Korean Journal of Food Science and Technology
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• v.42 no.5
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• pp.598-604
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• 2010

Electron donating ability (EDA), reducing power, total phenolic contents, total flavonoid contents, antimicrobial activity, and ${\alpha}$-glucosidase inhibitory effects of twenty-two sorghum varieties were examined using ethanol extracts (70%, v/v). The electron donationg abilities (EDA) of Mesusu and Bulgeunjangmoksusu (94% at 10 ${\mu}g$/mL) indicated higher antioxidant activity compared to those of other varieties and standard antioxidants such as BHT (13%) and BHA (74%). The reducing power of Mesusu ($OD_{700}$=0.71) suggested higher antioxidant activity, which was dependent on sample concentration. Bitjarususu showed the highest content of total phenolics (22.9 mg GAE/g); however, extracts from Heuinsusu exhibited the lowest content of total phenolics (16.4 mg GAE/g). Jangmoksusu showed the highest total flavonolic contents (3.5 mg QE/g), and Sigyeongsusu and Chal (GS) susu displayed the most antibacterial activity (MIC=8 ${\mu}g$/mL) against Escherichia coli. Extracts of Bulgeunjangmoksusu, Moktaksusu, and Ginjangmoksusu showed the highest ${\alpha}$-glucosidase inhibitory effect (98%) at the concentration of 5 ${\mu}g$/mL.

• Korean Journal of Plant Resources
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• v.26 no.5
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• pp.519-525
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• 2013

The Opuntia extract has been traditionally used to treat diabetes, inflammation, and rheumatoid arthritis in oriental medicine. The purpose of this study is to investigate characteristics of biological activity between Opuntia humifusa and Opuntia ficus-indica which is cultivating in korea using cell-free system or cell-based assay. O. humifusa extract effectively inhibited ${\alpha}$-glucosidase activity or improved the immune function, and its biological activity was more effective than O. ficus-indica extract. The scavenging activity of DPPH radical and the inhibitory effect of tyrosinase similarly showed by O. humifusa and O. ficus-indica extract, however neuroprotective effect only showed a tendency to increase compared with control in PC12 cells. Therefore the results suggest that O. humifusa can be a useful agent for treatment of diabetes and immunodeficiency.