• Microbiology and Biotechnology Letters
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• v.10 no.3
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• pp.197-203
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• 1982

The protopectinase from the culture extract of a Verticillium sp. was purified about 1000 fold by ammonium sulfate fractionation, DEAE-Sephadex treatment and Sephadex G-75 column chromatography. The purified enzyme was homogeneous on electrophoresis and its molecular weight was estimated to be 38000 by Andrew's gel filtration, method. The enzyme was almost stable under the temperature of 4$0^{\circ}C$ and within the pH range of 3-5. Its optimum pH and temperature were 4 and 4$0^{\circ}C$, respectively. The activity was markedly inhibited by galacturonic acid. The purified enzyme was able to macerate various kinds of plant tissues, such as radish, cucumber, onion, carrot, and potato. It also reduced the viscosity of pectin solution more rapidly than that of pectic acid solution and showed no lyase or CMCase activity.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.598-602
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• 1998

Twenty two rhizobacteria were isolated from the roots and rhizosphere of radish, carnation, potato and tomato. There isolates produced a fluorescent pigment in King's B medium and identified as Pseudomonas spp. These isolates colonized roots and rhizosphere of the host plants. In the study of cultural characteristics of the bacteria, the pH of the culture broth was changed from neutral (7.0) to alkali (8.8∼9.41) and the numbers of cells were increased from 106 to 108 after 40 hr of incubation in basal standard succinate medium. The salicylic acid production identified by pink color reaction were observed in 7 bacteria. Out of these 7 salicylic acid producing bacteria, only 2 strains of bacteria such as Pseudomonas fluorescens RS006, and Pseudomonas sp. EN401 were confirmed as salicylic acid producers by optical density measurement. Therefore, for screening of salicylic acid producing bacteria from the roots and rhizosphere, color reaction of the culture medium should be done in the first step, and then optical density measurement of culture extract should be made for the confirmation of salicylic acid production.

• Korean Journal of Microbiology
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• v.7 no.2
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• pp.86-90
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• 1969

1. Amylase producing bacteria have been isolated from natural sources and was identified out. The above strain is identical to Bacillus subtillis in every details of physiological and morphorogical characteristics by this investigations. 2. Sikworm chrysalis nad chlorella extracts are prove to be further effective for the stimulation of amylase production than any other sources. The former silkworm extract is more stronger in its activity. 3. It is found that effective results had been accepted by a less soybean meal addition per that of wheat bran in the mixture ratio of them, also less addition of corn is needed in the mixture ratio of between corn and whear bran. In the mixing ratio of wheat bran per silkworm or chlorella extracts, the addition of wheat bran is necessary for stimulation of amylase production. 4. Fro the stimulation of amylase production, the effective substances from natural sources and its order of activity in cultral media cultral media is proved as follows, silkworms ext.>chlorella ext.>alcohol>skim-milk and peptone>fermented milk>radish leaf ext.

• 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.

• The Korean Journal of Food And Nutrition
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• v.27 no.4
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• pp.609-618
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• 2014

We evaluated the yield of extract, antioxidant compounds (total phenolic, total flavonoid), antioxidant (DPPH assay, ABTS assay, Oyaizu's assay, FRAP assay), and antimicrobial activities of Siraegi (dried radish greens) according to cooking process (non-blanched, blanched, seasoned). The yield of non-blanched Siraegi was 4.91%, blanched Siraegi was 0.33%, and seasoned Siraegi was 7.55%. In total polyphenol and flavonoid contents, seasoned Siraegi extracts showed higher antioxidant compounds ($129.85{\pm}0.62mg$ GAE/100 g FW, $35.56{\pm}1.19mg$ CHE/100 g FW) than non-blanched and blanched. Total antioxidant activities (DPPH assay, ABTS assay, FRAP assay, reducing power) were shown to be in the order of seasoned Siraegi > non-blanched Siraegi > blanched Siraegi. In antimicrobial activity, non-blanched Siraegi (5, 10 mg/disc) showed antimicrobial activity against B. cereus, E. cloacae, and E. coli (9.25 mm), and P. aeruginosa (9 mm) at 10 mg/disc. In terms of antimicrobial activity, non-blanched Siraegi was good but eating the dried vegetable was difficult so it is essential to blanch it. Also, with many added seasonings in the process of cooking, it can be easy to eat. Overall, the results of this study demonstrate that cooked Siraegi with seasoning would be the most efficient way of ingesting the antioxidant material.

• Journal of Life Science
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• v.15 no.4 s.71
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• pp.561-565
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• 2005

In this study, we report antigenotoxicity and cytotoxicity of Korean Radish extract (RJ) and its seed protein (RSP) to non-tumoral 3T3 cell line. In the case of antigenotoxicity, each cell line was treated with $10{\mu}l\;of\;100{\mu}g/ml$ N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) before adding $10{\mu}l$of 10mg/ml RJ and 1mg/ml RSP to the cell. Both RJ and RS were shown $30\%\;and\;43\%$ of antigenotoxicity respectively. As a result of quantitative analysis for lactose dehydrogenase (LDH), no cytotoxic activity against 3T3 cells was detected when the cells were treated with various concentrations of RJ and RSP, RSP showed $85\%$ of antimicrobial activity against cosmetic sample (C1) assumed as contaminated by bacteria. RSP and RJ showed $79\%\;and\;76\%$ of antimicrobial activities repectively on another cosmetic sample (C4, contaminated by fungi) were treated with 10mg/ml RJ and 1 mg/ml RSP

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.652-662
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• 2000

This study was performed to measure the mutagenicity of fish by cooking and storage. Mutagenicity of the fish extract was measured by Ames test(Salmonella typhimurium reversion assay with TA 100) in vitro and by micro-nucleus test in vivo. The fish samples screened in this study were white fish(Trichiurus, Croaker, Salted Croaker) and red fish(Saury pike, Mackerel, Yellowtail, Salmon). The number of revertants of red fish were significantly higher than that of white fish. And the mutagenicity of mackerel was higher than other red fish, so followed experiment was made by using the extract of mackerel. Mutagenicity of the samples cooked on microwave oven was the lowest, whereas there was no significant difference between the samples cooked on gas grill and the ones on electric grill. In the presence of S9 mixture, the methanol extract of mackerel showed 2∼4 times high values of mutagenicity in comparison with the extract without S9. The extract of mackerel cooked with various vegetable juices showed inhibitory effects on the mutagenicity in the order of green tea, ginger, and radish. Also, the number of revertants was increased in the stored samples. Mutagenicity of the samples stored in the refrigerator was higher than that of the freezer. In micronucleus test, the methanol extract treated with vegetable juice inhibited micro-nucleus formation in bone marrow by cyclophosphamide in the order of ginger, green tea, and radish. In TBA test, there was a tendency that TBA values were increased as the storage time increased. Also, the rancidity of sample were stored in the refrigerator was higher value than sample stored in the freezer. Samples cooked on microwave oven showed the highest value in rancidity. When the antioxidant effect of vegetable juice was measured by electron donating ability(EDA) of mackerel cooked with vegetable juice to DPPH, the samples treated with onion showed the highest value of EDA(%), and the samples treated with green tea, ginger and cabbage also showed the antioxidant effect.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1537-1543
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• 2008

We tested Trichoderma harzianum as a biocontrol agent for Rhizoctonia solani AG2-1, using six natural antifungal materials to improve its efficacy. Among the six materials tested, peony (Paeonia suffruticosa) root bark (PRB) showed the strongest antifungal activity against R. solani AG2-1, and was not antagonistic to T. harzianum. Scanning electron microscopy showed that treatment with PRB extract resulted in shortened and deformed R. so/ani AG2-1 hyphal cells. The control of radish damping-off caused by R. so/ani AG2-1 was greatly increased by combined treatments of T. harzianum and PRB, as compared with either of the two treatments alone, with the control effect increased from 42.3-51.5% to 71.4-87.6%. The antifungal compound in PRB, which was isolated in chloroform and identified as paeonol by mass spectrometry, $^1H$ NMR, and $^{13}C$ NMR analyses, inhibited the growth of R. so/ani AG2-1 but not that of T. harzianum. Thus, PRB powder or extract may be used as a safe additive to T. harzianum to improve the control of the soil borne diseases caused by R. so/ani AG2-1.

• Korean Journal of Weed Science
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• v.14 no.1
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• pp.42-48
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• 1994

The toxic compounds of sorghum stem extracts were isolated by different organic solvents and pH, and characterized and quantified in terms of their inhibition of seed germination and seedling growth in Echinochloa colona(L.) Link and radish(Raphanus sativus L.). Sequential partitioning of stem extract with various organic solvents with increasing polarity showed that all fractions of hexane, ethyl ether, methylene chloride, ethyl acetate, and the aqueous remainder inhibited germination and seedling growth in E. colona. Of the five fractions, the ethyl ether fraction had the greatest inhibitory effect on E. colona. Further separation of the ethyl ether fraction at different pH(pH 2-11) showed that phytotoxic compounds were acidic. The result indicates that the phytotoxin present in the stem extract may be nonpolar and acidic.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.882-887
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• 1997

Quantitative determination of sulforaphane, S-methylsulfinylbutyl isothiocyanate in 20 cruciferous vegetables of Korean origin was performed. Homogenate of vegetable was extracted with dichloromethane, and the extract, after drying, was subjected to GC/MS analysis, which was based on single ion monitoring (SIM) at m/z 72, 160, 55, 114 and 177. The content of sulforaphane was found to be the highest in the extract of broccoli $(80.2{\sim}617.7\;ppm)$ followed by turnip $(15.4{\sim}23.1\;ppm)$, red cabbage $(9.9{\sim}32.1\;ppm),\;radish\;(5.5{\sim}8.8\;ppm)$ and kale (8 ppm). Among various cultivars of broccoli, broccoli '1243' and broccoli 'Pilgrim' showed higher content of sulforaphane than others. Especially, in the stem of broccoli '1243' and the floret of broccoli 'Pilgrim' the amount of sulforaphane was the highest (>700 ppm). Thus, the content of sulforaphane differed according to the cultivars and the portion of the vegetables.