• The Journal of Korean Medicine
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• v.22 no.2
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• pp.3-9
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• 2001

Objective : Oriental medicinal plants reported to be used as anti-hypertensive drugs have been in vitro screened for inhibitory effects on angiotensin-converting enzyme (ACE). Methods : The bioassay is based on inhibition of plasma angiotensin-converting enzyme, as measured from the enzymatic cleavage of the Hip-His-Leu substrate into His-Leu. The plant material is extracted with hexane, ethylacetate, n-buthanol and water separately. Results : In total, 51 species (202 extracts) have been investigated and $400{\;}\mu\textrm{g}/ml$ of the solvent extracts from 26 extracts inhibit the enzyme activities by more than 50%. Among them, four samples of two plant species (buthanol and ethylacetate extracts of Salvia miltiorrhiza and buthanol and water extracts of Jeffersonia dubia) were found to posses a high ACE inhibition ability more than 90%. Conclusion : These results suggested that many Oriental medicinal plants have a antihypertensive effects by inhibition of ACE.

• Korean journal of food and cookery science
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• v.14 no.5
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• pp.498-502
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• 1998

In order to develop a natural food preservative, freeze dried plantain (Plantago asiatica L.) was extracted with several solvents, and the antimicrobial activity was investigated. The methanol extract exhibited antimicrobial activites against five strains of bacteria such as Bacillus subtilis, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Vibrio parahaemolyticus. The methanol extract at the concentration of 1.0 mg/ml completely inhibited the growth of B. subtilis and V. parahaemolyticus. Antimicrobial activity of the ethylacetate fraction from the methanol extract was the strongest compared with those of other solvent fractions such as n-hexane, chloroform, n-butanol and water. The ethylacetate fraction showed the inhibitory effect at the concentration of 0.5 mg/disc on the growth of B. subtilis and V. parahaemolyticus.

• Microbiology and Biotechnology Letters
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• v.1 no.2
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• pp.105-113
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• 1973

The effect of biotin and biotin vitamer on the fermentative production of L-glutamic acid (L-GA) by Brevibacterium flavum was studied. And results were as follows. 1) L-GA production in the medium containing 10％ Glucose was the best at the concentration of Biotin 5${\gamma}$/l, Desthiobiotin 5${\gamma}$/1, and 7,8-Diaminopelargonic acid 10${\gamma}$/1, respectively. 2) In the experiment using the Glucose-Acetate mixed media derided into four parts, considerable amounts of cell growth and L-GA production were observed in the mixed medium containing 2％ Glucose-Acetate. 3) In the cases of using the media containing methanol, ethanol, ethylacetate, acetic acid (free acetate), Na-acetate:NH$_4$-acetate=2 : 1, the production of L-GA were in decreasing order as follows; Na-Acetate:NH-Acetate=2 : 1> Acetic acid (free acetate)> Ethylacetate> Ethanol＞ Methanol. 4) When biotin vitamers as growth factors were added in the medium containing Glucose or Acetate as the source of carbon, the substitution effect of Desthiobiotin was almost the same, 7,8-Diaminopelargonic acid 3 or 4 times stronger, and Bisnorbiotin has no substitution effect, compared with Biotin.

• The Korean Journal of Food And Nutrition
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• v.14 no.2
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• pp.120-125
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• 2001

The inhibitory effects of xanthine oxidase by the methanol extract and the solvent fractions obtained from persimmon leaves were investigated. The inhibition ratio of xanthine oxidase was 78% by addition of 2.0mg/ml of the methanol extract. Among the solvent fractions, the ethylacetate fraction showed the strongest inhibitory effect against the xanthine oxidase, followed by the hexane fraction. The effect increased with addition of the ethylacetate fraction. At a concentration of 2.0mg/ml of the ethylacetate fraction, 65% of the enzyme activity decreased within 1.0 min of incubation with xanthine oxidase. But the activity of xanthine oxidise did not decrease significantly by the length of the incubation time.

• Food Science and Biotechnology
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• v.18 no.5
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• pp.1193-1198
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• 2009

Ethylacetate and butanol fractions of leaf extracts (OLE) showed the higher contents of total phenolic compounds than hexane and water fractions. Oleuropein contents were $4.21{\pm}0.57,\;3.92{\pm}0.43,\;0.32{\pm}0.03,\;5.76{\pm}0.32$, and $32.47{\pm}0.25mg$/100g for ethanol extract, and hexane, chloroform, ethyl acetate, and butanol fraction, respectively. Treatment of ultraviolet-B (UVB) irradiated cells with 3 OLEs prepared by using ethylacetate and butanol at concentrations 0.001, 0.005, and 0.01% respectively showed significant recovery of cell viabilities. Treatment of dexametason 1 mM reduced tumor necrotic factor (TNF)-${\alpha}$ secretion by about 40%. UVB irradiated immortalized human keratinocytes (HaCaT) cells were treated with 3 different OLEs at the same concentrations. Ethylacetate fraction showed the strongest inhibition activity with respect of reduction of the elevated (TNF)-${\alpha}$. Cytotoxicity of OLEs on the B16-F1 cells was evaluated through thiazolyl blue tetrazolium bromide (MTT) assay. Ethylacetate fraction has no cytotoxicity in the range of 0.005-0.01%. A slight cytotoxicity was observed at the concentration of 0.1% butanol fraction of OLE that caused 10% decrease in cell viability.

• Korean Journal of Plant Resources
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• v.24 no.2
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• pp.200-207
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• 2011

This study was designed to investigate the possible utilization of Castanopsis cuspidata as a source of antiseptic agents. The leaves of C. cuspidata, extracted by 80% ethanol, were sequentially fractionated with n-hexane, dichloromethane, ethylacetate, and n-butanol. In order to effectively screen for a natural preservative agent, we first investigated the antioxidant activities such as DPPH radical scavenging capacity, superoxide radical scavenging capacity, and xanthine oxidase inhibitory activity of the C. cuspidata ethanol extracts and fraction. Using a screening system, we found that the ethylacetate fraction had the strongest antioxidant activity, which followed a dose-dependent manner. The antimicrobial activities were shown in the ethylacetate fraction of C. cuspidata. Among the five fractions, the ethylacetate fraction showed the highest antimicrobial activities against microorganisms tested, which were Bacillus sublitis, Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella enteritidis and Salmonella typhimurium. In addition, leaf extracts of C. cuspidata could be suitable for the development of food preservatives.

• Journal of the Korean Wood Science and Technology
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• v.28 no.2
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• pp.66-74
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• 2000

Wood of black locust(Robinia pseudoacacia) and bark of poplar(Populus alba x glandulosa), ash(Fraxinus rhynchophylla) and elm(Ulmus davidiana var. japonica) trees were collected, extracted with acetone-$H_2O$(7:3. v/v), fractionated with hexane, chloroform, ethylacetate and $H_2O$. then freeze dried to get some dark brown powder for bioactive tests. Decay-resistant activity was tested using wood block specimens from the hardwood trees and expressed by weight loss rate. Black locust specimens indicated the best anti-decaying property and poplar blocks were the worst. Antimicrobial and antioxidant activities were also investigated against each wood or bark extractives. Antifungal and antibacterial activities did not indicate any significant differences among the tested fractions. In antioxidant activity. ${\alpha}$-tocopherol one of natural antioxidants. and BHT, one of synthetic antioxidants, were used as references to compare with the antioxidant activities of the extracted fractions. Ethylacetate fraction of ash bark indicated the highest activity besides BHT in this test and all fractions of black locust extractives also indicated higher activities compared with the other fractions.

• Journal of Life Science
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• v.18 no.4
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• pp.467-473
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• 2008

This study was performed to investigate the antioxidant effect of 80% ethanol extracts from Pimpinella brachycarpa in vitro. The extraction yields of 80% ethanol extract was 9.23 g/100 g. The extract was further fractionated subsequently by n-hexane, chloroform, ethylacetate, n-butanol and water. Water fraction showed the highest extraction yield among fractions. Antioxidative activities of different fractions were examined by 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical generation, Rancimat test, thiobarbituric acid (TBA) value, nitrite scavenging activity, inhibition of lipid peroxidation and peroxide value in linoleic acid in comparison with the commercial antioxidant butylated hydroxytoluene (BHT). Antioxidant activities of n-hexane fraction of Pimpinella brachycarpa ethanol extract were the highest among fractions. Furthermore, the antioxidative capacity of the n-hexane fraction was similar to that of BHT.

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.228-235
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• 2013

Radish (Raphanus sativus) is a common cruciferous vegetable, and its aerial parts, called Mu-chung in Korean, have plentiful nutritional components such as vitamins, minerals and dietary fibers. Mu-chung has been used as a kimchi, a traditional Korean fermented dish, and dried Mu-chung is an important component of soups commonly consumed during winter in Korea. Since the advent of the mass production of radish in Korea, with the segregation of farm areas and towns and changing diets, Mu-chung has mostly been discarded instead of utilized. In addition, studies concerning the efficient utilization and useful bioactivities of Mu-chung are still lacking worldwide. In this study, we prepared the ethanol extract of Mu-chung and its subsequent solvent fractions. Antimicrobial, antioxidation, and anticoagulation activities were then evaluated in the hopes of developing a functional biomaterial from Korean radishes' aerial parts. The ethanol extraction yield for hot-air dried Mu-chung was 5.6%, and the fraction yields of n-hexane (H), ethylacetate (EA), butanol (B) and water residue were 25.3, 3.6, 19.4, and 51.7%, respectively. Analysis of total polyphenol and total flavonoid contents showed that the EA fraction had the highest content (97.57 and 152.91 mg/g) amongst the fractions. In antimicrobial activity assays, the H and EA fractions were effective against gram positive bacteria (Staphylococcus aureus, Listeria monocytogenes, and Bacillus subtilis), but not effective against gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa). The B fraction also exhibited moderate antibacterial activity, suggesting that the extract of Mu-chung has various antibacterial components. In antioxidation activity assays, the EA fraction showed strong DPPH, ABTS and nitrite scavenging activities ($69-222{\mu}g/ml$ of $IC_{50}$), including reducing power. In anticoagulation activity assays, the EA fraction demonstrated strong inhibition activity against human thrombin and prothrombin. Prominent anticoagulation activity was found in aPTT assays; the aPTT of the EA fraction was extended 15-fold compared than that of the solvent control. Our results suggest that Mu-chung is an attractive nutritional food material possessing useful bioactivities, and the EA fraction of Mu-chung could be developed as a functional food ingredient.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.989-994
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• 2007

This study was designed to investigate whether Sasa borealis leaves extracts (SLE) may inhibit yeast ${\alpha}-glucosidase$ and ${\alpha}-amylase$ activities and postprandial hyperglycemia in STZ-induced diabetic mice. Freeze-dried SLE was extracted with 70% methanol and followed by a sequential fractionation with dicholoromethan, ethylacetate, butanol, and water. Both ethylacetate and butanol fractions showed high inhibitory activities against the ${\alpha}-glucosidase$ and ${\alpha}-amylase$ enzymes. The $IC_{50}$ of ethylacetate and butanol fractions against ${\alpha}-glucosidase$ were 0.54 and 0.63 mg/mL, respectively, indicating a greater inhibition effect than acarbose (0.68 mg/mL) (p<0.05). Likewise, the two fractions exhibited a smaller $IC_{50}$ against ${\alpha}-amylase$, compared with acarbose (p<0.05). However, the yield of ethylacetate fraction of SLE was relatively small. Postprandial blood glucose testing of normal mice and STZ-induced diabetic mice by starch soln. loading (2 g/kg B.W.) showed that postprandial blood glucose level at 30, 60, and 120 min were markedly decreased by single oral administration of SLE butanol fraction (200 mg/kg B.W.) in both normal (p<0.0l) and diabetic mice (p<0.0l). Furthermore, the incremental area under the curve (AUC) was significantly lowered via SLE administration (5,745 versus 12,435 $mg{\cdot}mim/dL$) in the diabetic mice (p<0.0l). The incremental AUC in normal mice corroborated the hypoglycemic effect of SLE (p<0.0l) found in the diabetic mice. These results suggest that SLE may delay carbohydrate digestion and thus glucose absorption. In addition, SLE may have the potential to prevent and treat diabetes via its ability on lowering postprandial hyperglycemia.