• Korean Journal of Microbiology
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• v.42 no.2
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• pp.135-141
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• 2006

We isolated a bacterium which produces antifungal substances from the Sanktpeterburg soils at Russia. The iso-lated strain was identified as Brevibacillus sp. and shown a strong antifungal activity on plant pathogenic fungi. Brevibacillus sp. KMU-391 produced maximum level of antifungal substances under incubation aerobically at $30^{\circ}C$ for 48 hours in trypticase soybean broth containing 1.0% sucrose and 1.0% polypeptone at 180 rpm and initiated pH adjusted to 7.0. Precipitate of culture broth by $30{\sim}60%$ ammonium sulfate precipitation exhibited strong antifungal activity against Didymella bryoniae by dry cell weight. Butanol extract of cultured broth also shown fungal growth inhibitory activity against Botrytis cinerea KACC 40573, Botrytis fabae KACC 40962, Colletotrichum gloeosporioides KACC 40804, Colletotrichum orbiculare KACC 40808, Didymella bryoniae KACC 40669, Fusarium graminearum KACC 41040, Fusarium oxysporum KACC 40037, Fusarium oxysporum KACC 40052, Fusarium oxysporum f, sp. radicis-Iycopersici KACC 40537, Fusarium oxysporum KACC 40902, Monosporascus cannonballus KACC 40940, Phytophthora camvibora KACC 40160, Rhizoctonia solani AG-1(IA) KACC 40101, Rhizoctonia solani AG-4 KACC 40142, and Scleotinia scleotiorum KACC 41065 by agar diffusion method.

• Korean Journal of Organic Agriculture
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• v.25 no.4
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• pp.843-859
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• 2017

The JK-1 isolate which was the best producer of indole-3-acetic acid and carotenoid among the 388 strains isolated from 28 wetlands in Jeju, was identified to be Rhodopseudomonas palustirs belongs to a typical group of non sulfur purple bacteria based on 16S sRNA sequencing. This study investigated the effect of different cultural conditions of pH, temperature, agitation, light and aeration on growth, IAA and carotenoid production of photosynthetic bacterium JK-1 for optimization of IAA and carotenoid production. It was found that growth, IAA, carotenoid, and bacteriochlorophyll production with light (3,000~3,500 Lux) and agitation (100 rpm) showed better results than those with dark/static or dark/agitation (100 rpm) in anaerobic conditions. The optimal pH, temperature and agitation speed for cell growth were 7, $30^{\circ}C$, 150 rpm, for IAA production were 9, $30^{\circ}C$, 150rpm and for carotenoid production were 6, $25^{\circ}C$, 50 rpm, cultured for 72 h under anaerobic light, respectively. The growth and IAA production were high in aerobic culture compared with anaerocic culture, whereas carotenoid and bacteriochlorophyll content were decreased extremely in aerobic condition (0.5~1 vvm). Subsequently, the optimal culture conditions for JK-1 were selected with pH 7, $30^{\circ}C$ and 100 rpm under anaerobic light and the effect on plant growth was tested by pot assay. Inoculation of JK-1 with 3% (v/v) level caused increase in shoot and root dry weigh that varied from 20%~58% to 40%~28% in young radish in camparison to uninoculated treatment at 50 days of growth. The study suggests that the JK-1 isolate may serve as efficient biofertilizer inoculants to promote plant growth.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2003.04a
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• pp.61-62
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• 2003

Clonal propagation of high-value forest trees through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. A major barrier to the commercialization of this technology is the low quality of the resulting embryos. Several factors limit commercialization of SE for Corsican pine, including low initiation rates, low culture survival, culture decline causing low or no embryo production, and inability of somatic embryos to fully mature, resulting in low germination and reduced vigour of somatic seedlings. The objective was to develop a Corsican pine maturation medium that would produce cotyledonary embryos capable of germination. Treatments were arranged in a completely randomized design. Data were analyzed by analysis of variance, and significant differences between treatments determined by multiple range test at P=0.05. Corsican pine (Pinus nigra var. maritima) cultures were initiated on modified !P6 medium. Modifications of the same media were used for culture multiplication and maintenance. Embryogenic cultures were maintained on the same medium semi solidified with 2.5 g/l Gelrite. A maturation medium, capable of promoting the development of Corsican pine somatic embryos that can germinate, is a combination of iP6 modified salts, 2% maltose, 13% polyethylene glycol (PEG), 5 mg!l abscisic acid (ABA), and 2.5 g/l Gelrite. After initiation and once enough tissue developed they were grown in liquid medium. Embryogenic cell suspensions were established by adding 0.951.05 g of 10- to 14-day-old semisolid-grown embryogenic tissue to 9 ml of liquid maintenance media in a 250ml Erlenmeyer flask. Cultures were then incubated in the dark at 2022$^{\circ}$C and rotated at 120 rpm. After 2.53 months on maturation medium, somatic embryos were selected that exhibited normal embryo shape. Ten embryos were placed horizontally on 20 ml of either germination medium ($\frac{2}{1}$strength Murashige and Skoog (1962) salts with 2.5 g/l activated charcoal) or same medium with copper sulphate adjusted to 0.25 mg/1 to compensate for copper adsorption by activated carbon. 2% and 4% maltose was substituted by 7.5% and 13% PEG respectively to improve the yield of the embryos. Substitution of' maltose with PEG was clearly beneficial to embryo development. When 2% of the maltose was replaced with 7.5% PEG, many embryos developed to large bullet-shaped embryos. At latter stages of development most embryos callused and stopped development. A few short, barrel-shaped cotyledonary embryos formed that were covered by callus on the sides and base. When 4% of the maltose was removed and substituted with 13% PEG, the embryos developed further, emerging from the callus and increasing yield slightly. Microscopic examination of the cultures showed differing morphologies, varying from mostly single cells or clumps to well-formed somatic embryos that resembled early zygotic embryos only liquid cultures with organized early-stag. A procedure for converting and acclimating germinants to growth in soil and greenhouse conditions is also tested. Seedling conversion and growth were highly related to the quality of the germinant at the time of planting. Germinants with larger shoots, longer, straighter hypocotyls and longer roots performed best. When mature zygotic embryos germinate the root emerges, before or coincident with the shoot. In contrast, somatic embryos germinate in reverse sequence, with the cotyledons greening first, then shoot emergence and then, much later, if at all, the appearance of the root. Somatic seedlings, produced from the maturation medium, showed 100% survival when planted in a field setting. Somatic seedlings showed normal yearly growth relative to standard seedlings from natural seed.

• Korean Journal of Plant Resources
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• v.26 no.2
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• pp.149-158
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• 2013

The objective of this study was to investigate the antioxidative capacity of ethanol extracts from Sanguisorbae officinalis L. root (Sanguisorbae radix) in vitro. The concentration of Sanguisorbae radix extract at which DPPH radical scavenging activity was inhibited by 50% was 0.33 mg/mL, which was similar to $IC_{50}$ of ${\alpha}$-tocopherol (0.40 mg/mL), as compared to 100% by pyrogallol as a reference. Total antioxidant status was examined by total antioxidant capacity against ABTS radical reactions. Total antioxidant capacities of Sanguisorbae radix extract were significantly (p<0.05) higher than those of ${\alpha}$-tocopherol. Superoxide scavenging activities of Sanguisorbae radix extract were significantly (p<0.05) higher than those of catechin. Oxygen radical absorbance capacities of Sanguisorbae radix extract were significantly (p<0.05) higher than those of ascorbic acid. Cupric reducing antioxidant capacities of Sanguisorbae radix extract were significantly (p<0.05) higher than those of ${\alpha}$-tocopherol. Sanguisorbae radix extract prevented supercoiled DNA strand breakage induced by hydroxyl radical and peroxyl radical. Total phenolic contents of Sanguisorbae radix extract at concentrations of 0.5 and 5 mg/mL were 0.50 and 3.33 mM gallic acid equivalents, respectively. Sanguisorbae radix extract at concentration of 0.01, 0.1 and 0.5 mg/mL inhibited 0.2 mM tert-butyl hydroperoxide-induced cytotoxicity by 33.8, 79.1 and 96.9%, respectively, in HepG2 cell culture system. Thus, strong antioxidant and cytotoxicity-ihnibiting effects of Sanguisorbae radix extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation as well as high levels in total phenolic contents.

• Korean Journal of Plant Tissue Culture
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• v.24 no.2
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• pp.119-124
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• 1997

Plantlets were regenerated from various explants (shoot tip, leaf blade, petiole and root segments) via organogenesis and/or somatic embryogenesis from Armoracia rusticana(Lam) Gaerth., Mey, et Scherb.. Shoot regeneration rate from callus was highest on the MS mediums supplemented with 0.5 ㎎/L IAA, 5.0㎎/L BA and 10.0㎎/L spermine. A Low frequency of regeneration occurred on hormone-free MS medium. Multiple shooks were regenerated at a pH of 4.0 to 8.0 on MS medium supplemented with 1.0 ㎎/L BA and 0.1 ㎎/L NAA. Polyamines promoted shoot- and root-formation by 2 to 4 times normal, Specific proteins associated with organogenesis were identified. Somatic embryogenesis occurred directly from the leaf blade, petiole and root segments cultured on MS medium with 2.0 ㎎/L BA and 2.0 ㎎/L BA and 2.0 ㎎/L NAA. Three types of regeneration in A, rusticana were clearly established, which could be applied to the study of morphogenesis and genetics at cell, tissue and organ levels.

• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.323-328
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• 2006

A bacterium producing the extracellular protease was isolated from insect-eating plant and has been identified as a member of the genus Bacillus based on partial 165 rRNA sequences. In order to develop the medium composition, effects of ingredients including nitrogen sources, carbon source, metal ions and phosphate were examined for protease production of the isolate, SH-8. Soluble starch increased the protease productivity, while glucose repressed it. Yeast extract was effective nitrogen source for enzyme production, but the pretense production of Bacillus sp. SH-8 was reduced by large amount of yeast extract. The calcium was found to induce pretense activity as well as protease productivity. However, cell growth and enzyme production was completely inhibited by divalent ions such as $Zn^{2+}$, $Cu^{2+}$, $Co^{2+}$ and $Mn^{2+}$. The maximum protease productivity was reached 435 unit/ml in the optimized medium consisting of soluble starch (2%), yeast extract (0.3%), $CaCl_2$ (0.3%), $K_2HPO_4$ (0.01%) and $KH_2PO_4$ (0.01%). The pretense activity of culture filtrate was dramatically decreased after incubation for 26 h.

• Korean Journal of Plant Resources
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• v.23 no.5
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• pp.445-450
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• 2010

This study was carried out to investigate the antioxidative capacity of Ampelopsis brevipedunculata 95% ethanol extracts. The concentration of A. brevipedunculata extract at which DPPH radical scavenging activity was inhibited by 50% was 0.42 mg/mL as compared to 100% by pyrogallol as a reference. Total antioxidant status was examined by total antioxidant capacity against ABTS radical reactions. Total antioxidant capacities of A. brevipedunculata extract at the concentrations of 0.1 and 1 mg/mL were 0.65 and 3.71 mM Trolox equivalents, respectively. Oxygen radical absorbance capacities of A. brevipedunculata extract at the concentrations of 5 and $100\;{\mu}g/mL$ were 22.75 and $131.25\;{\mu}M$ gallic acid equivalents, respectively. Superoxide scavenging activities of A. brevipedunculata extract at the concentrations of 0.1 and 1 mg/mL were 27.7 and 56.0%, respectively. Total phenolic contents of A. brevipedunculata extract at the concentrations of 0.5 and 2.0 mg/mL were 0.55 and 2.06 mM gallic acid equivalents, respectively. A. brevipedunculata extract at the concentration of 0.1 mg/mL inhibited 0.2 mM and 0.5 mM tert-butyl hydroperoxide induced cyototoxicity by 36.2 and 23.3%, respectively, in HepG2 cell culture system. Thus strong antioxidant and cytotoxicity-inhibiting effects of A. brevipedunculata extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation as well as high levels in total phenolic contents.

• Journal of Bio-Environment Control
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• v.18 no.1
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• pp.67-73
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• 2009

This study was conducted to gather the basic data on making good use of a kind of groundsel (Ligularia fischeri). We have made methanol extracts from Ligularia fischeri and have also determined the effects of extracting temperature and time on the physiological activities of methanol extracts from Ligularia fischeri. Total phenolic compound and flavonoid contents in the methanol extracts from Ligularia fischeri at the extracting concentration of $1,000mg{\cdot}L^{-1}$ were $75.8-297.7mg{\cdot}L^{-1}$ and $45.6-173.6mg{\cdot}L^{-1}$. Total phenolic compound and flavonoid contents, and DPPH radical scavenging activities were most increased when Ligularia fischeri was extracted with methanol at $95^{\circ}C$ for 6 hours, however, nitrite radical scavenging activities were extremely increased at $75^{\circ}C$ for 12 hours by 97.4%. At $200mg{\cdot}L^{-1}$ and $400mg{\cdot}L^{-1}$ methanol extracting concentration, the hyperplasia of lung cancer cells (Calu-6) and stomach cancer cells (SNU601) were effectively inhibited over 90%. Consequently, it was assumed that Ligularia fischeri was a functional vegetable with a higher physiological activities. Making the processed foods, it had better make the extracts from Ligularia fischeri with methanol at $95^{\circ}C$ for 6 hours.

• Research in Plant Disease
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• v.11 no.2
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• pp.158-161
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• 2005

Stenotrophomonas maltophilia BW-13 is a potent biocontrol agent to control crisphead lettuce bottom rot caused by Rhizoctonia solani. To define the optimum conditions for the mass production of the S. maltophilia BW-13, we have investigated optimum culture conditions and effects of various carbon sources on the bacterial growth. The optimum initial pH and temperature were determined as pH $6.0\~7.0 and $35^{\circ}C$, respectively. For the selection of effective carbon source for the mass production, we tested the low molecular carbon sources such as sucrose, glucose, lactose, maltose, manose and the high molecular carbon source such as dough conditioner, rice bran, corn starch, sweet potato starch. As the results, the addition of dough conditioner in a basal medium ($1.25\%\;K_{2}HPO_4,\;0.38\%\;KH_{2}PO_4,\;0.01\%\;MgSO_4{\cdot}7H_{2}O,\;0.5\%\;Yeast extract$) was able to achieve higher cell density and the antifungal activity than others. Therefore, the basal medium containing $3\%$ dough conditioner (named as dough conditioner medium) was finally selected the optimized media for the mass production of BW-13 strain.

• Korean Journal of Plant Resources
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• v.24 no.4
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• pp.456-460
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• 2011

The objective of this study was to investigate the antioxidative capacity of Rhododendron brachycarpum 95% ethanol extracts. Total antioxidant status was examined by total antioxidant capacity against ABTS radical reactions. Total antioxidant capacities of R. brachycarpum extract at the concentrations of 0.2 and 1 mg/mL were 0.33 and 2.26 mM Trolox equivalents, respectively. Superoxide scavenging activities of R. brachycarpum extract at the concentrations of 0.2 and 1 mg/mL were 45.0 and 77.0%, respectively. Oxygen radical absorbance capacities of R. brachycarpum extract at the concentrations of 5 and 100 ${\mu}g/mL$ were 40.88 and 131.00 ${\mu}M$ Trolox equivalents, respectively. Total phenolic contents of R. brachycarpum extract at the concentrations of 0.2 and 1 mg/mL were 0.37 and 1.25 mM gallic acid equivalents, respectively. R. brachycarpum extract at the concentration of 0.1 mg/mL inhibited 0.2 mM and 0.5 mM tert-butyl hydroperoxide induced cyototoxicity by 52.1 and 30.3%, respectively, in HepG2 cell culture system. Thus, strong antioxidant and cytotoxicity-inhibiting effects of R. brachycarpum extract seem to be due to, at least in part, the prevention from free radicals-induced oxidation as well as high levels in total phenolic contents.