• Journal of Mushroom
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• v.7 no.4
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• pp.156-162
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• 2009

These experiments were carried out to determine the optimal culture conditions for nine strains of collected Hatakeshimeji, Lyophyllum decastes (Fr.:Fr.) Sing. SPA 202 and SPA 205 strains were selected because mycelium grew fast and showed fine density. All strains showed fast mycelial growth and mycelial density on BC(Burke compost) media for 20 days of incubation. The optimal sawdust species for the mycelial growth were the fermented sawdusts of Quercus aliena and Populus deltoides. Spawn running period on the fermented sawdust substrate required 50 days at 20 to $25^{\circ}C$ and additional 7 days after soil casing. Cultivation period and temperature forprimordia formation and fruitbody development appeared from 10 to 11 days and from 7 to 8 days at 17 to $18^{\circ}C$ respectively. The length of pilei and stipes of SPA 202 harvested in optimal stage showed 60mm and 67mm, respectively. Yield of SPA 202 strain grown on fermented sawdust substrate was 130g per 1,100ml in bottle cultivation. The length of pilei and stipes of SPA 205harvested in optimal stage showed 51mm and 81mm, respectively. Yield of SPA 205 strain grown on fermented sawdust substrate was 129g per 1,100 ml in bottle cultivation. SPA 202 strain and SPA 205 strain in artificial bottle cultivation of Lyophyllum decastes used in fermented sawdust substrate were selected as themost appropriate strain in yield.

• Korean Journal of Environmental Agriculture
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• v.13 no.3
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• pp.311-320
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• 1994

This study was conducted to investigate the biochemical properties of isolated bacteria, low temperature tolerant methane-producing clostridia which were selected for using them as inoculum to anaerobic fermentation of agricultural and livestock wastes at low temperature. The results were; 1. Low temperature tolerant methane-producing clostridia were isolated from the samples which showed the high methanogenesis rate by enrichment culture at low temperature in cellulose medium. These clostridia, Clostridium botulinum SRC-64, Clostridium scatologens SRC-91 and Clostridium tyrobutyricum SRC-100, were isolated from swampy sediment at latitude $56.9^{\circ}N$, lake sediment IV at latitude $55.0^{\circ}N$, and tidal land soil II at latitude $37.0^{\circ}N$, respectively. The optimum growth temperature for these isolates was $37^{\circ}C$ and the minimum, around $10^{\circ}C$. They all had detectable amount of $F_{420}$, specific coenzyme of methanogens. 2. As anaerobic fermentation products of glucose SRC-64 produced $H_2$, acetic, isovaleric and caproic acid, SRC-91 produced $H_2$, propionic, butyric, valeric, and caproic acid, and SRC-100 produced only acetic and propionic acid. The isolates were produced $CH_4$ ranged from 2.6 to 8.68 n moles/ml for 2 days at $13^{\circ}C$.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.57-65
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• 2012

Fertilization is essential to seedling production in nursery culture, but excessive fertilization can contaminate surface and ground water around the nursery. The objective of this study was to find optimal fertilization practice of container seedling production for reducing soil and water contamination around the nursery without compromising seedling quality. This study was conducted to investigate chemical properties of the growth medium, growth performance, chlorophyll fluorescence, and chlorophyll contents of larch ($Larix$ $kaempferi$) growing under three different fertilization treatments (Constant rate, Three stage rate, and Exponential rate fertilization). Root collar diameter and height of larch were not significantly different among treatments even though the nutrient supply of the exponential treatment was half that of the constant and three stage treatments. Chemical properties of the growth medium showed the same trends as root collar diameter and height. The total biomass and seedling quality index (SQI) were higher at Constant than at other treatments, but both SQI of Constant and Exponential were not significantly different. Photochemical efficiency and chlorophyll contents were lower at Exponential than at other treatments, but not significantly different among treatments. Therefore, Exponential fertilization which is 50% fertilizer of other treatments would maximize seedling growth and minimize nutrient loss.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.6
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• pp.522-527
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• 2004

Barley growing in paddy fields often suffers from wet-injury due to oxygen deficiency in rhizospere caused by excessive water in the soil. This study was conducted to investigate responsiveness of growth, development and anaerobic glycolysis enzymes to acute hypoxia in barley seedlings. Barley seedlings at the third leaf stage were subjected to hypoxia (1 ppm dissolved oxygen) by sparging the culture solution with nitrogen gas for up to seven days. Length and fresh weights of the shoot and root were affected little by hypoxia for up to 5 days. But root dry weight was slightly decreased by hypoxia for 7 days. In the root, alcohol dehydrogenase and lactate dehydrogenase activities increased drastically under hypoxia, reaching at their maximum levels in 3 to 5 days of hypoxia and decreasing slightly thereafter. However, the activities of both enzymes changed little in the shoot. Increases of their activities in the root were contributed by all the isozymes found in barley. These results suggest that barley seedlings first adapt to hypoxia by rapidly activating fermentative glycolysis to stabilize cellular pH and to increase energy production for the following morphological adaptative changes.

• BMB Reports
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• v.37 no.3
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• pp.282-291
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• 2004

Phytases catalyze the release of phosphate from phytic acid. Phytase-producing microorganisms were selected by culturing the soil extracts on agar plates containing phytic acid. Two hundred colonies that exhibited potential phytase activity were selected for further study. The colony showing the highest phytase activity was identified as Aspergillus niger and designated strain 113. The phytase gene from A. niger 113 (phyI1) was isolated, cloned, and characterized. The nucleotide and deduced amino acid sequence identity between phyI1 and phyA from NRRL3135 were 90% and 98%, respectively. The identity between phyI1 and phyA from SK-57 was 89% and 96%. A synthetic phytase gene, phyI1s, was synthesized by successive PCR and transformed into the yeast expression vector carrying a signal peptide that was designed and synthesized using P. pastoris biased codon. For the phytase expression and secretion, the construct was integrated into the genome of P. pastoris by homologous recombination. Over-expressing strains were selected and fermented. It was discovered that ~4.2 g phytase could be purified from one liter of culture fluid. The activity of the resulting phytase was 9.5 U/mg. Due to the heavy glycosylation, the expressed phytase varied in size (120, 95, 85, and 64 kDa), but could be deglycosylated to a homogeneous 64 kDa species. An enzymatic kinetics analysis showed that the phytase had two pH optima (pH 2.0 and pH 5.0) and an optimum temperature of $60^{\circ}C$.

• Korean Journal of Microbiology
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• v.49 no.1
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• pp.78-82
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• 2013

A novel Chryseobacterium sp. JK1 strain isolated from soil had been reported that this isolate produced large amount of extracellular protease at mesophilic temperature in previous study. The optimal temperature and pH of extracellular protease were $40^{\circ}C$ and 7.0, respectively, showing narrow range of optimal temperature and relatively broad activity from pH 6.0 to 9.0. In addition, the protease showed greatest activity against skim milk and lowest against bovine serum albumin (BSA). The protease strongly inhibited by ethylenediaminetetraacetic acid (EDTA), ethylene glycol tetraacetic acid (EGTA) or phenylmethylsulfonyl fluoride (PMSF), and addition of cation $Ag^+$ or $Cu^{2+}$, and slightly inhibited by $Al^{3+}$. No significant inhibition was found with pepstatin, and addition of cation, $K^+$, $Ca^{2+}$, $Na^+$, $Fe^{2+}$ or $Mg^{2+}$. On the contrary, protease was enhanced by addition of divalent cation $Mn^{2+}$ (5 mM). Zymography analysis of concentrated culture supernatant revealed two major bands at 67 and 145 kDa. These results suggest that Chryseobacterium sp. JK1 strain produced extracellular neutral serine proteases which could apply in food industry.

• Korean Journal of Environment and Ecology
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• v.25 no.1
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• pp.111-117
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• 2011

The purpose of this study is to establish trail use impact indicators, and evaluate the degree of use impact based on the understanding of the causality among the impacts on the spot. Theoretical reviews developed three indicators in terms of three ecological impacts, four physical impacts, and five sociological impacts, respectively. With this indicators, observation and questionnaire survey were employed on Gwanak Mountain Trail to measure the levels of impacts forementioned. As for the ecological impact, Some loss of ground cover vegetation was reveled near the trail due to trail use, however the level of disturbance by the naturalized and exotic plants was insignificant. Physical impacts such as soil hardness, enlargement of trail width were found intensified. The result of measuring sociological impacts showed visitors had expected higher level of crowding and encounters before their visit, therefore overall satisfaction level was positive, despite higher awareness level of actual crowding. Intensified continuing use of the trail is aggravating ecological and physical impacts on Gwanak Mountain trail, because of its location in a metropolitan area. Sociological impacts seem favorable at present, however if ecological and physical impacts were deteriorated, sociological impacts would also be affected. To maintain the quality level of use experience, managerial efforts to improve climbing culture as well as ecological and physical environment such as restoration of damaged areas are needed.

• Microbiology and Biotechnology Letters
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• v.4 no.4
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• pp.166-178
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• 1976

Taxonomic study of 11 strains of Bacillus coagulans and 14 strains of 13 spccies of Bacillus by deoxyribonucleic acid (DNA)-DNA hybridization were conducted. Among the 11 strains of B. coagulans, 6 were isolated from soil and the rest were the authentic strains obtained from American Type culture collection (ATCC) or the Institute for Fermentation, Osaka (IFO). All strains were examined to confirm as they are expected species of B. coagulans by the methods of Cordon et al. according to Bergey's Manual (8th ed.). The intraspecific DNA homology indexes among the 11 strains of B. coagulans using strain ATCC 7050 as the standard ($^3$H labeled input DNA) showed 76％ or, more, respectively. These findings accorded well with the results of the conventional taxonomic study according to the Bergey's Manual. The interspecific DNA homology indexes between B. coagulant strain ATCC 7050 and the type cultures of B. subtilis (168), B. licheniformis (IFO 12107), B. pumilus (IFO 12110), B. firmus (ATCC 14575), B. lentus (ATCC 10840), B. circulans (ATCC 4513), B. macelans (ATCC 8244), B. polymyxa (ATCC 842), B. sphaericus (ATCC 14577), B. brevis (ATCC 8246, IFO 12334), B. laterosporus (ATCC 64), and B. pantothenticus (ATCC 14576) respectively, showed 2 to 4％, while that of between B. coagulans ATCC 7050 and Escherichia coli K-12 was less than 1 ％.

• Journal of Plant Biotechnology
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• v.32 no.1
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• pp.51-55
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• 2005

Chinese leymus (Leymus chinensis Trin.) is a perennial grass that is widely distributed at high pH sodic and arid soil in the northeastern Asia. An efficient regeneration system was established through somatic embryogenesis of mature seeds to understand its high adaptability to harsh environmental conditions on the basis of molecular biology. The calli were efficiently induced (about $70\%$) from mature seeds on MS medium supplemented with $1.5\;\cal{mg/L}$ 2,4-D. Somatic embryos were formed from the surface of embryogenic callus on MS medium supplemented with $2.0\;\cal{mg/L}\;kinetin\;and\;0.5\;\cal{mg/L}$ NAA after 3 weeks of culture. Roots were induced from the shoot when transferred to MS medium without plant growth regulator for 1 week. Plant regeneration rate was $36\%$ and regenerated plantlets were grown to normal mature plants in pot. An efficient plant regeneration system in this study will be useful for molecular breeding of L. chinensis.

• Journal of Plant Biotechnology
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• v.32 no.4
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• pp.301-306
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• 2005

Conditions for efficient organogenesis and plant regeneration from Dianthus gratianopol suspension cultured cells were established. Shoot-forming calli of glossy surface, pale green and knobby type were selected from leaf explant-derived calli and were suspension-subcultured every week in CP liquid medium with 1.0 mg/L 2,4-D and 0.5 mg/L BAP. Combinations of 1.0 mg/L 2,4-D and 0.5 mg/L BAP, and 1.5 mg/L 2,4-D and 0.5 mg/L BAP were effective for the induction of regenerative callus from the suspension cultured cell clusters. Multiple shoot primordia were initiated from the green spots of these regenerative callus and formed shoots on MS medium with 1.0 mg/L TDZ and 0.5 mg/L PAA. Shoot regeneration frequency (calli regenerating at least one shoot) was about 87%. For plant regeneration, proliferated shoots were excised and transferred to MS medium with 0.1 mg/L NAA for root initiation after 9 weeks of culture. The regenerants were potted in soil and formed the flowering buds and petals. Also, adventitious shoots were formed from the excised green shoot primordia of regenerative callus and these shoots proliferated successfully and regenerated to whole plants.