• Journal of Life Science
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• v.30 no.5
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• pp.443-451
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• 2020

Recently, thrombotic diseases have become rapidly more prevalent due to Westernized lifestyles and high-fat diets. In this study, the anti-thrombosis activities of the aerial parts of Sageretia thea were evaluated using ethanol extracts of the leaf (ST-L), branch (ST-B), and fruit (ST-F), and their anti-coagulation, platelet aggregation inhibition, and hemolytic toxicity were assessed. In comparison to the ST-F extract, the ST-B exhibited 6.7 times more polyphenol content, and the ST-L had 2.7 times more total flavonoid content. The ST-L and ST-B extracts showed stronger inhibitions of thrombin, prothrombin, and blood coagulation factors than aspirin, berry extracts, or commercial oriental herbs. Furthermore, ST-L and ST-B showed superior platelet aggregation-inhibitory activities than aspirin. The ST-F extract demonstrated only minor anti-thrombosis effects, and none of the extracts showed hemolysis against red blood cells up to 1 mg/ml. Phenolic acid and flavonoid analysis of the ST-L and ST-B extracts showed abundant rutin, isoquercitrin, and astragalin as the major active compounds. Further research on the anti-thrombotic activity of isoquercitrin, a rare flavonoid from quercetin, is necessary. This is the first report of isoquercitrin in Sageretia thea, and our results suggest that ST-L and ST-B extracts could therefore developed as anti-thrombosis agents.

• Journal of Life Science
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• v.29 no.1
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• pp.52-59
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• 2019

The leave of Polygonum tinctorium (LPT) have been used for centuries as a traditional medicine and as a food ingredient and natural dye. The aim of the current study was to develop high-value added products using LPT. Hot water extract (HWE) and ethanol extract (EE) of LPT were prepared, respectively, and their bioactivity was evaluated. The extraction ratio for the HWE was 27.6%, which was two-fold higher than that of the EE. The contents of total polyphenol in the HWE and total sugar in the EE were 51.2 mg/g and 297.8 mg/g, respectively. The total flavonoid and reducing sugar contents were similar in the extracts, irrespective of the extraction solvent. The HWE did not show antimicrobial activity in a disc-diffusion assay, but the EE showed strong growth inhibition against gram-positive bacteria. The EE exhibited stronger DPPH and ABTS radical scavenging activities and reducing power than those of the HWE. The HWE was particularly effective as a scavenger of nitrite ($RC_{50}$ of $6.0{\mu}g/ml$). In an antithrombosis activity assay, the EE showed significant anticoagulation activity as determined by an extended blood coagulation time (thrombin time, prothrombin time, and activated partial thromboplastin time), in addition to platelet aggregation activity. The HWE also showed platelet aggregation inhibitory activity. This report provides the first evidence of antithrombosis activities of LPT. Our results suggest that LPT has potential as a new antioxidant and antithrombosis agent.

• Journal of Life Science
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• v.34 no.3
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• pp.153-159
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• 2024

Dioscorea alata L, commonly known as "tropical yam" is the most widely consumed yam species among the 650 yam species belonging to the Dioscoreacea family. It is extensively cultivated in tropical and subtropical regions and is a major food source in Africa and India. Also, it is used for medicinal purposes, particularly in China and Taiwan, for its anti-inflammatory properties. In comparison to other yam varieties such as D. batatas or D. opposita, the tropical yam has gained popularity in Korea due to its higher yield per unit area. In this study, the nutritional characteristics and anti-thrombosis activity of the aerial bulbils of D. alata L. tropical yam were compared to those of D. opposita. The results showed that the aerial bulbils of tropical yam exhibited nutritional characteristics and potent anticoagulant activity compared to those of domestic yam varieties. The bulbils extract of tropical yam showed superior anticoagulant activities against thrombin, prothrombin and blood coagulation factors. Furthermore, the bulbils extract of tropical yam exhibited strong platelet aggregation inhibition at 0.25 mg/ml and showed no hemolytic activity up to a concentration of 2.5 mg/ml. These findings suggest the potential development of high-value anti-thrombosis agents utilizing the aerial bulbils of tropical yam.

• Microbiology and Biotechnology Letters
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• v.42 no.3
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• pp.285-292
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• 2014

In the course of study for development of functional food ingredients from aged black garlic (ABG), heat-treated ripe bulbs of Allium sativum L., the water extracts from raw-garlic (RG) and ABG, and the subsequent organic solvent fractions of ABG were prepared, and their antioxidant, antimicrobial, and antithrombosis activities were compared. The extraction yield of ABG was 4-folds higher than that of RG, and the contents of total polyphenol, total flavonoid, total sugar and reducing sugar in the ABG extract were 4-folds, 1.56-folds, 3.36-folds and 6.75-folds higher than those of the RG extract, respectively. In antioxidation activity assay, the extract of ABG showed minor scavenging activity against DPPH anion, but revealed strong scavenging activity against ABTS cation and nitrite. Especially, the ethylacetate fraction from the ABG extract demonstrated stronger antioxidation activity than the RG extract and other fractions. Although the antimicrobial and antithrombosis activities of the RG extract did not appear in the ABG extract, the ethylacetate fraction from the ABG extract had antibacterial activity against Staphylococcus aureus and Bacillus subtilis, and strong antithrombosis activity via the inhibition of prothrombin, blood coagulation factors and platelet aggregation. All extracts and fractions did not show any hemolytic activity against human red blood cells up to 5 mg/ml. Our results suggest that the ethylacetate fraction of ABG could be applicable to the development of functional food ingredients for antithrombosis agents.

• Journal of Life Science
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• v.24 no.8
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• pp.865-872
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• 2014

In this study, ethanol and hot water extracts of lees from Korean traditional wine (J-B, J-S, J-Y, J-H, and J-W) were prepared, and their effects on blood coagulation, platelet aggregation, and hemolysis of human red blood cells (hRBCs) were investigated to develop functional food ingredients from lees. The pH and brix of the lees ranged from 3.90 to 4.29 and 5.0 to $27.0^{\circ}$, respectively, and there was a huge difference in the water and ethanol content among the lees. The nuruk and additives used affected the color and physicochemical properties of lees. The J-W takju made from only rice and traditional nuruk, which has $13^{\circ}$ brix and 1.8% of alcohol, has potential as functional food ingredient. With regard to the extraction yields of lees, higher yields were obtained from J-H, which contains different medicinal plants, in ethanol, followed by J-W, J-B, J-S, and J-Y. Higher extraction yields of lees were obtained from J-S in hot water, followed by J-B, J-W, J-H, and J-Y, respectively. The ethanol extract of J-H and the hot water extract of J-Y had the highest contents of total polyphenol and total flavonoids among the lees extracts. The 10 lees extracts did not show hemolysis activity against hRBCs up to 5 mg/ml. In an anticoagulation activity assay, the ethanol extracts of three yakju lees (J-B, J-S, and J-Y) and the hot water extract of J-W inhibited thrombin activity, whereas the hot water extract of J-B, J-S, and J-H inhibited blood coagulation factors. In an antiplatelet aggregation activity assay, only the J-W takju lees showed significant inhibition activity. Our results suggest that lees from traditional wine had high potential as a novel antithrombosis agent.

• Journal of Life Science
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• v.29 no.2
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• pp.164-172
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• 2019

In Korea, shiitake mushroom, Lentinula edodes, is cultivated on artificial medium containing oak sawdust and wheat bran. The annual production of spent mushroom substrate (SMS) of shiitake, a byproduct of the mushroom industry, is estimated to reach over 50,000 tons per year. This study aimed to improve the use of SMS as a novel bioresource. Hot water extracts of SMS after the first and third harvest were prepared and their bioactivities evaluated. Hot water extracts of uninoculated medium and shiitake were used as controls. Extracts of SMS showed higher radical scavenging of DPPH anions, ABTS cations, nitrites, and a higher reducing power than those of shiitake or medium extracts. After the first and third harvests at 0.5 mg/disc, SMS extracts showed no antibacterial or antifungal activities against the pathogenic and food-spoilage bacteria and fungi. However, they showed good inhibitory activities against ${\alpha}$-glucosidase at 0.5 mg/ml. In addition, SMS extracts had strong anti-coagulation activities via their inhibition of thrombin, prothrombin, and blood coagulation factors without platelet aggregation activity. Our results suggested SMS should no longer be perceived as a useless byproduct but should be understood as a novel bioresource, the extracts of which could be developed as antioxidant, antidiabetic, and antithrombosis agents.

• Journal of Life Science
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• v.19 no.9
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• pp.1245-1250
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• 2009

Beimu (Fritillaria thunbergii Miquel), a bulbous plant of Liliaceae found in Korea, Japan and China, has been used as an antitussive and expectorant agent, and is also useful in alleviating stonsillitis and bronchiolitis. Most researches have been focused on micro-propagation and plant regeneration, component analysis, and dormancy relieving of beimu. Reports regarding the biological activity of beimu, such as anti-Helicobacter pyroli or platelet aggregation inhibition activity, are few and not widely available. In this study, methanol extract and its organic solvent fractions were prepared from Fritillaria thunbergii Miquel and their antimicrobial, antithrombin, and antioxidant activities were evaluated, respectively. The methanol extract contained lots of water-soluble materials (58.98%) and hexane-soluble oils (14.85%). The ethylacetate and butanol fraction at $500{\mu}g$/disc concentration showed strong antibacterial activity against tested bacteria, except Escherichia coli. Antifungal activity was not observed in methanol extract and its fractions. The hexane, ethylacetate and butanol fractions showed strong antithrombin activity at 4.8 mg/ml concentration. Especially, the ethylacetate fraction showed 95.4 sec of thrombin time at a concentration of 1.2 mg/ml, which is comparable to aspirin, a widely used antithrombosis agent. For antioxidation activity, the ethylacetate and butanol fraction showed good 1,1-diphenyl-2-picryl hydrazyl scavenging activity ($IC_{50}$ of $344{\sim}368{\mu}g$/ml). In superoxide dismutase-like activity and reducing power, the fractions showed $20{\sim}25%$ of vitamin C, and $51{\sim}54%$ of butyl hydroxytoluene, respectively.

• Tuberculosis and Respiratory Diseases
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• v.45 no.6
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• pp.1265-1276
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• 1998

Background : Nitric oxide(NO) is an endogenously produced free radical that plays an important role in regulating vascular tone, inhibition of platelet aggregation and white blood cell adhesion to endothelial cells, and host defense against infection. The highly reactive nature of NO with oxygen radicals suggests that it may either promote or reduce oxidant-induced cell injury in several biological pathways. Oxidant injury and interactions between pulmonary vascular endothelium and leukocytes are important in the pathogenesis of acute lung injury, including acute respiratory distress syndrome(ARDS). In ARDS, therapeutic administration of NO is a clinical condition providing exogenous NO in oxidant-induced endothelial injury. The role of exogenous NO from NO donor or the suppression of endogenous NO production was evaluated in oxidant-induced endothelial injury. Method : The oxidant injury in cultured rat lung microvascular endothelial cells(RLMVC) was induced by hydrogen peroxide generated from glucose oxidase(GO). Cell injury was evaluated by $^{51}$chromium($^{51}Cr$) release technique. NO donor, such as S-nitroso-N-acetylpenicillamine(SNAP) or sodium nitroprusside(SNP), was added to the endothelial cells as a source of exogenous NO. Endogenous production of NO was suppressed with N-monomethyl-L-arginine(L-NMMA) which is an NO synthase inhibitor. L-NMMA was also used in increased endogenous NO production induced by combined stimulation with interferon-$\gamma$(INF-$\gamma$), tumor necrosis factor-$\alpha$(TNF-$\alpha$), and lipopolysaccharide(LPS). NO generation from NO donor or from the endothelial cells was evaluated by measuring nitrite concentration. Result : $^{51}Cr$ release was $8.7{\pm}0.5%$ in GO 5 mU/ml, $14.4{\pm}2.9%$ in GO 10 mU/ml, $32.3{\pm}2.9%$ in GO 15 mU/ml, $55.5{\pm}0.3%$ in GO 20 mU/ml and $67.8{\pm}0.9%$ in GO 30 mU/ml ; it was significantly increased in GO 15 mU/ml or higher concentrations when compared with $9.6{\pm}0.7%$ in control(p < 0.05; n=6). L-NMMA(0.5 mM) did not affect the $^{51}Cr$ release by GO. Nitrite concentration was increased to $3.9{\pm}0.3\;{\mu}M$ in culture media of RLMVC treated with INF-$\gamma$ (500 U/ml), TNF-$\alpha$(150 U/ml) and LPS($1\;{\mu}g/ml$) for 24 hours ; it was significantly suppressed by the addition of L-NMMA. The presence of L-NMMA did not affect $^{51}Cr$ release induced by GO in RLMVC pretreated with INF-$\gamma$, TNF-$\alpha$ and LPS. The increase of $^{51}Cr$ release with GO(20 mU/ml) was prevented completely by adding 100 ${\mu}M$ SNAP. But the add of SNP, potassium ferrocyanate or potassium ferricyanate did not protect the oxidant injury. Nitrite accumulation was $23{\pm}1.0\;{\mu}M$ from 100 ${\mu}M$ SNAP at 4 hours in phenol red free Hanks' balanced salt solution. But nitrite was not detectable from SNP upto 1 mM The presence of SNAP did not affect the time dependent generation of hydrogen peroxide by GO in phenol red free Hanks' balanced salt solution. Conclusion : Hydrogen peroxide generated by GO causes oxidant injury in RLMVC. Exogenous NO from NO donor prevents oxidant injury, and the protective effect may be related to the ability to release NO. These results suggest that the exogenous NO may be protective on oxidant injury to the endothelium.