• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.373-381
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• 2011

This study was carried out to investigate the growth and physiological responses to shading treatment of 1-year-old containerized seedling of Quercus myrsinaefolia. Experimental process was conducted in a facility that consisted of compartments under the lighting control with full sunlight and shading (35%, 55% and 75% of full sunlight). Height and root collar diameter growth were high in the seedlings under both 35% and 55% shading. Regardless of shading level, root collar diameter growth lasted for more than 4 weeks compared to height growth. Highest H/D ratio was observed in the seedlings under 35% shading as 4.31, and the lowest ratio was 3.63 under 75% shading. It was found that seedlings under 55% shading showed highest dry mass production, which was followed in seedlings under 35% shading. In case of leaf dry weight ratio (LWR) after shading treatment, the highest value was 0.53 under 55% shading, and followed in seedlings under 35% shading as 0.52. But root dry weight ratio (RWR) was highest as 0.36 under 75% shading (highest level of shading). In terms of shading treatment, it was found that the higher level of shading had a tendency toward the higher content of chlorophyll a and the higher total chlorophyll content in the leaves of Quercus myrsinaefolia, but there was no significant difference in the content of chlorophyll b depending on the level of shading. It was found that high photosynthesis and transpiration rate were more correlated with high level of shading than full sunlight, but the rates of seedlings had a tendency to be higher under 35% and 55% shading than under 75% shading. The results on growth and physiological responses to different shading levels of 1-year-old containerized seedlings of Quercus myrsinaefolia could be useful in setting up the optimum light intensity for growth, and in estimating the shade tolerance of the species.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.111-118
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• 1996

For the screening and the development of the new bio-material, cultural conditions for the exo-biopolymer (EBP) production throught the submerged cultivation of Ganoderma lucidum mycelium were investigated. Also, the fractionations and the purifications of the exo-biopolymer were carried out and the chemical compositions of the exo-biopolymer were examined. The optimal culture conditions for the exo-biopolymer production were pH 5.0, 30$^{\circ}C$ and 100 rpm of agitation speed in the medium containing of 5% (w/v) glucose, 0.5%(w/v) yeast extract, 0.1% (w/v) ($(NH_4)_2HPO_4$, and 0.05% (w/v) $KH_2PO_4$. In the flask cultivation for 7 days under these conditions, the concentration of the maximum exo-biopolymer and the cell mass were 15.4g/l and 18.8g/l, respectively. The specific growth rate was 0.039 $hr^{-1}$. In addition, the substrate consumption rate, and the exo-biopolymer production rate were 0.043$gg^{-1}$$hr^{-1}$ and 0.025$gg^{-1}$$hr^{-1}$, respectively. The exo-biopolymer was fractionated into BWS (water soluble exo-biopolymer) and BWI (water insoluble exo-biopolymer) by the water extraction, and the sugar contents of two fractions were higher than 97% (based on dry basis). The components sugar of BWS and BWI fractions were glucose, galactose, mannose, xylose, and fucose. Their molar ratios were 3.6:1.5:2.1:0.5: trace and 2.9:3.1:2.0:1.6:0.3, respectively.

• Journal of Korean Society of Forest Science
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• v.99 no.1
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• pp.125-130
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• 2010

The application of bioreactor culture techniques for plant micropropagation is regarded as one of the ways to reduce production cost by scaling-up and automation. In an attempt to optimize mass proliferation systems in Eucalyptus pellita, four types of bioreator systems including temporary immersion system with or without net were tested. Highest growth was achieved with 30-min flushes of medium at every 4-h intervals in TIN (temporary immersion with net) system. Results indicate over three-fold increase in shoot growth with the TIN system when compared with TIX (control: temporary immersion without net) system which is without net in bioreactor. Furthermore, plants produced from the TIN system increased total chlorophyll content, chlorophyll a/b and dry matter, giving higher yields of acclimatized plants. Our findings suggest that plantlet growth increases with appropriate exposure to media at correct intervals, as well as use of net for maintaining aerobic condition in the vessels. The TIN system thus has great potential for in vitro mass production of Eucalyptus clones commercially.

• The Plant Pathology Journal
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• v.23 no.3
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• pp.174-179
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• 2007

Seedlot disinfection techniques to control mung bean sprout rot caused by Colletoricum acutatum and C. gloeosporioides were evaluated for commercial production scheme. Soaking seedlots in propolis (100 X) and ethanol (20% for 30 min) appeared promising with control values of 85.5 and 80.8 respectively, but still resulted in up to 20% rot incidence. None of the C. acutatum conidia survived through hot water immersion treatment (HWT) for 10 min at temperatures of 55, 60 and $65^{\circ}C$, whereas the effective range of the dry heat treatment (DHT) was $60-65^{\circ}C$. Tolerance of mung bean seedlot, as estimated by hypocotyl elongation and root growth, was lower for HWT than for DHT. Germination and growth of sprouts were excellent over the range of $55-65^{\circ}C\;at\;5^{\circ}C$ intervals, except for HWT at $65^{\circ}C$ for 5 min. At this marginal condition, heat damage appeared so that approximately 2% of seeds failed to sprout to normal germling and retarded sprouts were less than 5% with coarse wrinkled hypocotyls. These results suggested that DHT would be more feasible to disinfect mung bean seedlots for commercial sprout production. Heat treatment at above ranges was highly effective in eliminating the epiphytic bacterial strains associated with marketed sprout rot samples. HWT of seedlot at 55 and $60^{\circ}C$ for 5 min resulted in successful control of mung bean sprout rot incidence with marketable sprout quality. DHT at 60 and $65^{\circ}C$ for 30 min also gave good results through the small-scale sprouting system. Therefore, we optimized DHT scheme at 60 and $65^{\circ}C$ for 30 min, considering the practical value of seedlot disinfection with high precision and accuracy. This was further proved to be a feasible and reliable method against anthracnose incidence and those bacterial strains associated with marketed sprout rot samples as well, through factory scale mung bean sprout production system.

• The Plant Pathology Journal
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• v.33 no.3
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• pp.329-336
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• 2017

An experiment was conducted to evaluate the tolerance of micropropagated and mycorrhized alpinia plants to the parasite Meloidogyne arenaria. The experimental design was completely randomized with a factorial arrangement of four inoculation treatments with arbuscular mycorrhizal fungi (AMF) (Gigaspora albida, Claroideoglomus etunicatum, Acaulospora longula, and a non-inoculated control) in the presence or absence of M. arenaria with five replicates. The following characteristics were evaluated after 270 days of mycorrhization and 170 days of M. arenaria inoculation: height, number of leaves and tillers, fresh mass of aerial and subterranean parts, dry mass of aerial parts, foliar area, nutritional content, mycorrhizal colonization, AMF sporulation, and the number of galls, egg masses, and eggs. The results indicated a significant interaction between the treatments for AMF spore density, total mycorrhizal colonization, and nutrient content (Zn, Na, and N), while the remaining parameters were influenced by either AMF or nematodes. Plants inoculated with A. longula or C. etunicatum exhibited greater growth than the control. Lower N content was observed in plants inoculated with AMF, while Zn and Na were found in larger quantities in plants inoculated with C. etunicatum. Fewer galls were observed on mycorrhized plants, and egg mass production and the number of eggs were lower in plants inoculated with G. albida. Plants inoculated with A. longula showed a higher percentage of total mycorrhizal colonization in the presence of the nematode. Therefore, the association of micropropagated alpinia plants and A. longula enhanced tolerance to parasitism by M. arenaria.

• Microbiology and Biotechnology Letters
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• v.2 no.2
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• pp.79-82
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• 1974

Present experiments were designed to estimate the effects of pretreatments by various kinds of alkalis to the agricultural wastes such as cereal straws as the substrate on the production of cellulosic single-cell protein. Among the various kinds of alkalis NaOH was proved to be the most effective on improving the digestibility of cellulose by the bacteria isolated. NH$_4$OH which is inferior to NaOH in the effectiveness of treatment might have more economic advantage in the price, and the ammonium salt resulted from the neutralization can be used as the nitrogen source by bacteria. The treatment with higher concentration than 1 normality of NH$_4$OH didn't increase the productivility of cell mass. About five per cent of (NH$_4$)$_2$SO$_4$ in medium resulted from the neutralization didn't have any influence in the cell mass productivility. Futhermore, the cell mass productibility was higher in the case of neutralization than alkali free washing. The digestibility of straws was increased from 7.9％ to 46.0％ by NH$_4$OH treatment, and 6.3∼6.45g of dry cell were obtained from 40g of NH$_4$OH treated straws. In the case of NaOH treatment, 8.6g of cell mass was obtained from 40g of substrate.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.845-849
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• 2010

This study was conducted to compare various culture methods and evaluate economic feasibility of each method for mass propagation of new ever-bearing strawberry 'Goha'. Four different methods such as semi-solid culture, solid culture, liquid suspension culture and bioreactor culture were compared. The solid culture and bioreactor culture showed the shortest and longest root length, such as 3.6 cm and 8.3 cm, respectively. Fresh weights of plants cultured in bioreactor were 2,261 mg, which were heavier than those of cultures. Dry weights of plants cultured in bioreactor were the heavier compared to those in other cultures. The number of axillary bud developed in bioreactor was seven, but axillary bud was not developed in other cultures. Production cost through bioreactor culture was calculated to be 303 won per plant which was 542 won less than that of solid culture. As a result, we found that the bioreactor culture was the most cost effective culture method for in vitro mass propagation in new ever-bearing strawberry 'Goha'.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.301-305
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• 2001

The co-expression of the arg U gene in a double-vector expression system of recombi-nant Escherichia coli BL22(DE3)[pET-IEN2a+pAC-argU] significantly enhanced the production level of reconminant human interferon -$\alpha$2a(rhIFN-$\alpha$2a) in high cell density cultures, compared to a recombinant E. coli culture containing only the single expression vector, pET-IEN2a. The dry cell mass concentration increased to almost 100 g/L, and more than 4 g/L of rhIFN-$\alpha$2a was accumu-lated in the culture broth. Evidently, the synthesis of rhIFN-$\alpha$2a was strongly dependent on the pre-induction growtih rate and more efficient at a higher specific growth rate. The additional sup-ply of tRN $A^{Arg(AGG/AGA)}$ enhanced the expression level of the rhIFN-$\alpha$2a gene in the early stage of the post-induction phase, yet thereafter the specific production rate of rhIFN-$\alpha$2a rapidly de-creased due to severe segregational instability of plasmid vector pET-IEN2a. It would appear that the plasmid instability with only occurred to pET-IEN2a in the double vector system, was re-lated to the effect of translational stress due to the over expression of rhIFN-$\alpha$2a.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.1
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• pp.1-7
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• 1997

This experiment was conducted with total 960 brown layers, consisted of 8 treatment to investigate the effects of dietary chromium as chromium picolinate on egg production, egg quality, nutrient utilizability, serum traits and mortality in brown layers. Layers were fed diets with two levels of dietary protein (14% and 16%) and supplemented with 0, 200, 400, 800 ppb/kg of chromium as chromium picolinate, respectively. The highest egg production, egg weight and egg mass were found in 800 ppb chromium picolinate supplementation group with high protein level (16%) (p < 0.05). Although there was no significant difference, layers receiving 400 ppb of chromium picolinate with high protein (16%) represented the lowest broken eggs. The utilization of energy, dry matter and crude protein of 400 ppb chromium picolinate group with low protein level (14%) were significantly higher than those of control or other chromium picolinate group (p < 0.05). 400 ppb chromium picolinate with low protein level (14%) showed the lowest serum glucose concentration. But serum glucose concentrations in all treatments showed no significant differences. Present date revealed that the lowest serum cholesterol concentration of layers was found at 400 ppb chromium picolinate group with high protein level (16%) (p < 0.05). Crude protein content in yolk was significantly higher in eggs of layers received 800 ppb chromium picolinate and the lowest in eggs from layers received 400 ppb chromium picolinate among chromium picolinate levels (p < 0.05). Mortality was remarkably decreased by chromium picolinate supplementation and the lowest mortality value was found in layres receiving 800 ppb chromium picolinate with high protein level.

• The Korean Journal of Mycology
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• v.31 no.3
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• pp.187-191
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• 2003

Armillaria mellea, honey mushroom is well known as a symbiotic fungus with Gastodia elata, The mycelial yields of the fungus were compared when cultured with various broth media. The highest yield of cell mass, 2.31 g dry weight/50mL, was obtained on germinated-malt extract broth (GMEB). The optimal broth concentration which was measured hand refractometer for mycelium production was $15\;Brix^{\circ}$. The optimal conditions estimated with response surface methodology under temperature, pH and incubation period were $25.9^{\circ}C$, pH 5.72, 15.22 days, respectively, on GMEB having $15\;Brix^{\circ}$ concentration for mycelial production of A. mellea.