• Journal of the Korean Wood Science and Technology
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• v.42 no.5
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• pp.624-633
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• 2014

This study separated the crude extract (70% ethanol) of and its three fractions (hexane, chloroform and ethyl acetate extracts) on the basis of polarity indexes, and examined for their insecticidal activities against aphid (Uroleucon lactucicola). For crude extraction, the 70% ethanol extract showed the best extract yield (58.0%) and insecticidal activity (69.0%) among the various concentrations tested (water, 30% ethanol, 50% ethanol, 70% ethanol and 95% ethanol). The major chemical compounds of different fractions (hexane, chloroform and ethyl acetate extracts) were identified as eugenol by head space-GC-MS analysis. The hexane extract showed the highest eugenol content (43.7%) and insecticidal activity (80.0%). The insecticidal activity is accordingly believed to be attributable to the eugenol component. This may provide a useful starting point for the development of bio-pesticides.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.100-106
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• 1999

Use of chemical preservative for controlling harmful microorganisms in food products has been debated due to public concerns about food quality because of perceived toxic and carcinogenic potential. Thus, use of non toxic natural antimicrobial agents has become essential. This study was investigated to determine the antimicrobial activity of water or ethanol extract of commercially available tea, and of solvent fractionated ethanol extracts obtained from steamed green tea. Both of water and ethanol extracts of green tea(steamed or roasted), oolong tea and black tea exhibited strong antimicrobial activity against gram positive and negative bacteria, but not effective against yeast and mold. Also, antimicrobial activity of ethanol extract of 4 different kinds of tea was stronger than that of water extract. Among 4 different tea, ethanol extract of steamed green tea was further fractionated. One thousand g/disk buthanol extract had the strongest antimicrobial activity against bacteria and mold. The concentration of the antimicrobial activity of buthanol extract in tested microorganisms ranged from 125~1000 g/disk except for Rhizopus javanicus. Antimicrobial activity of buthanol extract of steamed green tea was not destroyed by heating at 100oC for 60 min and at 121oC for 15 min, which is very stable over heat treatment. The inhibitory effect of the buthanol extract on the growth of Listeria monocytogenes and Staphylococcus aureus was investigated. Growth of both strains was started in the presence of 250 and 500 g/ml after 12 and 24 hour respectively, whereas complete inactivation of both strains was occurred in the presence of 1000 g/ml.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.625-632
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• 2009

This study determined the effects of added buckwheat extract on the rate of corn starch hydrolysis in vitro as well as blood glucose responses through its supplementation in healthy subjects. The rate of corn starch hydrolysis in the presence or absence of various buckwheat extracts was determined in an in vitro enzyme/dialysis system for 2 hr. The buckwheat was extracted by water, ethanol(40%, 70%, 100%) and methanol(40%, 70%, 100%), respectively. Twenty percent(w/w) additions of the ethanol, methanol and water buckwheat extract to corn starch solution significantly reduced the starch hydrolysis at every minute for 2 hr(p<0.05). The calculated hydrolysis indices of the buckwheat extracts were in the order of 100% ethanol extract(50), 100% methanol(54), 40% ethanol(58), 40% methanol(62), 70% methanol(64), 70% ethanol(68), water (82). For the blood glucose response study, groups of 12 volunteers were given 50 g of boiled rice with or without buckwheat extract(10% and 20% of starch weight) using the 100%, 70%, and 40% ethanol extracts, respectively. The addition of each buckwheat ethanol extract significantly reduced blood glucose concentrations at three or more points during 2 hr and also reduced the mean peak rise and area under the blood glucose curve(p<0.05). The calculated glycemic index(GI) values for all ethanol buckwheat extract groups were significantly decreased compared to the control(rice). At the concentrations of 20%, the buckwheat 100% ethanol extracts lowered the GI by 68%. The 100% ethanol extract was more effective than the 70% and 40% extracts for reducing GI. Therefore, the 100% ethanol buckwheat extract would be the most therapeutically useful in modifying postprandial hyperglycemia.

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.419-424
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• 2018

In this work, effect of the culture medium composition on the fermentation process of Clostridium ljungdahlii, which is acetogenic bacteria to product ethanol from synthesis gas, was examined to improve the microbial growth and ethanol production. Components of the culture medium such as yeast extract, fructose, $NH_4Cl$, and $K_2HPO_4$ were selected as influence factors for the cell growth and ethanol production. As the concentration of yeast extract increased, both of the cell growth and ethanol production increased. And the ethanol productivity was the highest at an yeast extract of 0.05 g/L, which is lower than that of base medium. As the concentration of fructose increased, the cell growth increased, but the ethanol production decreased when the concentration of fructose was higher than that of base medium (5 g/L). In an experiment with the yeast extract of 5 g/L, produced ethanol concentration was the highest (0.297 g/L) when fructose concentration was 5 g/L, however, the specific ethanol productivity was higher (0.281 g/g DCW) when the fructose was not added due to very low cell mass. The cell growth and ethanol production were not significantly influenced by $NH_4Cl$ concentration, however the growth inhibition was observed at a 30 g/L of $NH_4Cl$. When the concentration of $K_2HPO_4$ increased, both of the cell growth and ethanol production increased. In experiments with $NH_4Cl$ and $K_2HPO_4$, specific ethanol productivities were higher when the low concentration of yeast extract was used.

• Journal of Life Science
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• v.27 no.1
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• pp.23-31
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• 2017

This study was performed to determine the ethanol ratios (30%, 50%, 70%, and 90%) of extraction solvent of Seomaeyakssuk (Artemisia Argyi H.) prepared using different methods (drying at room temperature [D], aging at $60^{\circ}C$ for 7 days after drying [AD], and roasting for 30 min at $160^{\circ}C$ after drying [RD]). The extract yield of the D extracts was lower than that of the AD and RD extracts, but the ethanol concentration of extract solvent did not affect. The L, a, and b values of the D extracts were highest, whereas those of the AD extracts were lowest. No clear trend was observed in the ethanol ratios. The soluble solids, total phenol, total flavonoid, jaceosidin, and eupatilin contents of each extract varied significantly, with RD > AD > D. The soluble solids significantly increased by ethanol ratio of extraction solvent, but other phytochemicals contents of 50% and 70% ethanol extracts were higher than others without affecting the processing methods. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was highest (77.71%) in the 70% ethanol extract obtained from RD. 2,2-azinbis-(3-ethylbenzo-thiazoline-6-sulphonate(ABTS) radical scavenging activity was significantly higher in 30-70% ethanol extract than 90% ethanol extract from RD. The results suggest that the contents of active ingredients and radical scavenging activity of ethanol extracts from Seomaeyakssuk were highest in the RD extract using 50-70% ethanol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.581-587
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• 1996

This study was done to investigate the effects of Artemisia selengensis methanol extract on ethanol-induced hepatotoxicty in rat liver. Sprague-Dawley(SD) rats weighing about 150g were divided into the following 4 groups : control group(CON), Astemisia selengensis methanol extract administered group(ASE), ethanol adminstered group(ETH) and Artemisia selengenis methanol extract and ethanol administered group(ASA). Ethanol and Artemisia selengenis methanol extract were administered orally by 5m1/kg and 200mg/kg body weight per day for 6weeks, respectively. Body weight, daily food intake and percent liver weight per body weight were significantly changed by ethanol administration in comparison to control group. The activities of serum alanine aminotransferase(ALT), asparate aminotransferase(AST), and hepatic TBA-reactants increased by ethanol were decreased significantly by Artemisia selengensis methanol extract compared with ethanol group. It was also obseued that superoxide dismutase, catalase and glutathione peroxidase were not changed by Artemisia selengensis methanol extract, whereas hepatic xanthine oxidase activity was inhibitied by Artemisia selengensis methanol extract as compared to ethanol group. The glutathione contents in liver decreased by ethanol adminstration, but glutathione levels increased in ASA compared with ethanol group. These results suggest that Artemisia selengenis methanol extract have a possible protective effect on the ethanol-induced hepatotoxicity in rat liver.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.199-203
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• 2007

Dental caries is a major worldwide oral disease problem. Streptococcus mutans (S. mutans) plays an important role in the information of dental plaque and it is being noticed as major causative bacteria of dental caries. Therefore, the development of more effective, substantial and safe preventive agents against dental caries is strongly required. In the present study, inhibitory effects of the ethanol extract of the husk of pomegranate (Punica granatum L.) on the growth, acid production, adhesion and water-insoluble glucan synthesis of Streptococcus mutans (S. mutans) were examined. The ethanol extract of pomegranate husk (250 - 4000 ${\mu}$g/ml) significantly lowered the growth of S. mutans in a dose dependent manner. The acid production of S. mutans were inhibited by the presence of ethanol extract of pomegranate husk (500 - 4000 ${\mu}$g/ml) significantly. The ethanol extract of pomegranate husk (5000 - 4000 ${\mu}$g/ml) also significantly lowered the adherence of S. mutans. In water-insoluble glucan synthesis assay, 1000 - 4000 ${\mu}$g/ml of the ethanol extract of pomegranate husk significantly inhibited the formation of water-insoluble glucan. These results suggest that pomegranate husk may inhibit the caries-inducing properties of S. mutans. Further studies are necessary to clarify the active constituents of pomegranate husk responsible for such biomolecular activities.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1364-1368
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• 1999

This study was carried out to investigate the inhibiton effects of Coprinus comatus ethanol extract of edible mushroom on liver damage in benzo(a)pyrene (B(a)P) treated mice. The activities of serum aminotransferase, cytochrome P 450 and hepatic content of lipid peroxide after B(a)P treatment were increased than those of control, but those levels were significantly decreased by the treatment of Coprinus comatus ethanol extract. Whereas, the hepatic glutathione content and glutathione S transferase activity were decreased by B(a)P treatment than those of control, but those were increased by the treatment of Coprinus comatus ethanol extract. Also the activities of superoxide dismutase, catalase and glutathione peroxidase after B(a)P treatment were markedly increased than those of control, but those levels were decreased by the treatment of Coprinus comatus ethanol extract. These results suggest that Coprinus comatus ethanol extract have a protective effect on liver damage by benzo(a)pyrene through the mechanisms of decreasing lipid peroxide and activities of free radical generating enzymes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.443-450
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• 2011

The effects of dietary supplementation with Hizikia fusiformis on anti-hyperlipidemic activities were investigated in an animal study in which normal rats were fed Hizikia fusiformis, Hizikia fusiformis ethanol extract and Hizikia fusiformis ethanol extract residue. Serum total lipid and triglyceride levels were significantly (P<0.05) reduced in rats fed Hizikia fusiformis ethanol extract residue at a dose of 200 mg/kg body weight when compared to hyperlipidemic control rats. There were also significant decreases in serum total cholesterol and LDL-cholesterol levels in the rats fed Hizikia fusiformis ethanol extract residue at 200 mg/kg body weight. In addition, the atheroscrelosis index and superoxide dismutase in blood lipids were significantly (P<0.05) lowered in rats fed Hizikia fusiformis ethanol extract residue at 200 mg/kg body weight, as compared to control rats. In conclusion, Hizikia fusiformis and Hizikia fusiformis ethanol extract residue had beneficial antihyperlipidemic and antiarteriosclerosis effects.

• Toxicological Research
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• v.12 no.2
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• pp.251-258
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• 1996

Panax ginseng has been used for various diseases including hepatic disorders. The aim of the present study was to investigate the hepatoprotective effects of ethanol extract and saponin of Panax ginseng in thioacetamide-intoxicated rats and to compare with silymarin, a known hepatoprotective agent. Male Sprague-Dawley rats were given single intragastric administration of thioacetamide. Aqueous solutions of ethanol extract and saponin of Panax ginseng with or without silymarin were administered intragastrically daily for six days from four days before until one day after thioacetamide administration. At the end of the treatment, the rats were fasted overnight and sacrificed. As a result, thioacetamide caused significant increase in serum levels of AST, ALT, 5'-nucleotidase and bilirubin. Thioacetamide increased $Ca^++$ content but decreased protein content in liver tissue. These thioacetamide-induced biochemical changes were prevented both by ethanol extract of ginseng and silymarin, but not by ginseng saponin. Silymarin did not potentlate the effect of either ethanol extract or saponin of ginseng on these parameters. Thioacetamide-induced confluent necrosis was not protected by the test drugs. In conclusion, ethanol extract of ginseng protects the liver possibly by stabilizing the cell membrane and by inhibiting thioacetamide-induced $Ca^++$ increase in the hepatocytes, which was comparable to that of silymarin.