• Plant Biotechnology Reports
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• v.2 no.3
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• pp.171-177
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• 2008

This paper reports an improved protocol for isolation, culture and regeneration of Lotus corniculatus protoplasts. A range of parameters which influence the isolation of L. corniculatus protoplasts were investigated, i.e., enzyme combination, tissue type, incubation period and osmolarity level. Of three enzyme combinations tested, the highest yield of viable protoplasts was achieved with the combination of 2% Cellulase Onozuka RS, 1% Macerozyme R-10, 0.5% Driselase and 0.2% Pectolyase. The use of etiolated cotyledon tissue as a source for protoplast isolation proved vital in obtaining substantially higher protoplast yields than previously reported. Culture of the protoplasts on a nitrocellulose membrane with a Lolium perenne feeder-layer on the sequential series of PEL medium was highly successful in the formation of microcolonies with plating efficiencies 3-10 times greater than previous studies. Shoot regeneration and intact plants were achieved from 46% of protoplast-derived cell colonies.

• Structural Monitoring and Maintenance
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• v.10 no.3
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• pp.243-260
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• 2023

Indonesia has had seismic codes for earthquake-resistant structures designs since 1970 and has been updated five times to the latest in 2019. In updating the Indonesian seismic codes, seismic hazard maps for design also update, and there are changes to the Peak Ground Acceleration (PGA). Indonesian seismic design uses the concept of building performance levels consisting of Immediate occupancy (IO), Life Safety (LS), and Collapse Prevention (CP). Related to this performance level, cases still found that buildings were damaged more than their performance targets after the earthquake. Based on the above issues, this study aims to analyze the performance of base isolation design on existing target buildings and analyze the seismic fragility for a case study in Indonesia. The target building is a prototype design 8-story medium-rise residential building using the reinforced concrete moment frame structure. Seismic fragility analysis uses Incremental Dynamic Analysis (IDA) with Nonlinear Time History Analysis (NLTHA) and eleven selected ground motions based on soil classification, magnitude, fault distance, and earthquake source mechanism. The comparison result of IDA shows a trend of significant performance improvement, with the same performance level target and risk category, the base isolation structure can be used at 1.46-3.20 times higher PGA than the fixed base structure. Then the fragility analysis results show that the fixed base structure has a safety margin of 30% and a base isolation structure of 62.5% from the PGA design. This result is useful for assessing existing buildings or considering a new building's performance.

• Journal of the Korean Society of Tobacco Science
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• v.15 no.2
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• pp.130-136
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• 1993

Protoplasts of palisade cells were aseptically isolated from leaves of Nicotiono apicona Merxm. by the one step enzymatic method. Efficiency of colony formation were depended on cell density and light condition during incubation, but an intensity of 47 ft-c during a period of 2 weeks after isolation of the protoplasts in the Nagata and Takebe's medium promoted the planting efficiency. Protoplast - derived calli of N. africana can be differentiated into shoot when cultured on Murashige and skoog's medium containing IAA(0.Smg/$\ell$) and zeatin(5.0mg/$\ell$).

• Journal of Plant Biology
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• v.26 no.4
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• pp.191-196
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• 1983

The isolatin and culture of protoplasts from hypocotyl originated callus of Phaseolus vulgaris cv. Damyang were carried out. The maximum protoplast yield of 4.6$\times$105 per gram fresh callus, using the 13-day-old callus, was obtained by digeston for 6 hours in the enzyme solution. After 10 day-culture of the isolated callus protoplsts, plating efficiency was 50%. Thereafter, cell cluster medium, and followed by leading to callus formation on an agar medium after 3 weeks of the liquid culture.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.331.1-331.1
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• 2002

Actinomycetes CS0703 has been isolated in soil sample from location in the Jeju province. Korea. and produces alkaline extracellular proteases. To maximize protease production, initial pH of the culture medium was adjusted to 12.0 with NaOH and incubated at $48^{\circ}C$ on a rotary shaking incubator(180rpm). Actinomycetes CS0703 produced high level of protease at late exponential phase when grown in OSYM medium (oatmeal 2.0%. soybean meal 1%. dried yeast 1%. mannitol 1%). (omitted)

• Journal of Microbiology and Biotechnology
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• v.33 no.8
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• pp.1066-1075
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• 2023

Kimchi is a traditional Korean fermented vegetable that is stored and fermented at low temperatures. However, kimchi lactic acid bacteria (LAB) are typically isolated under mesophilic conditions, which may be inappropriate for isolating the diverse LAB. Therefore, this study investigated the suitable conditions for isolating various LAB from kimchi. Here, LAB were isolated from four kimchi samples using MRS, PES, and LBS media and varying isolation temperatures (30, 20, 10, and 5℃). Then, MRS was selected as the suitable medium for LAB isolation. A comparison of culture-dependent and culture-independent approaches indicated that 5℃ was not a suitable isolation temperature. Thus, the number and diversity of LAB were determined at 30, 20, and 10℃ using 12 additional kimchi samples to elucidate the effect of isolation temperature. With the exception of two samples, most samples did not substantially differ in LAB number. However, Leuconostoc gelidum, Leuconostoc gasicomitatum, Leuconostoc inhae, Dellaglioa algida, Companilactobacillus kimchiensis, Leuconostoc miyukkimchii, Leuconostoc holzapfelii, and Leuconostoc carnosum were isolated only at 10 and 20℃. The growth curves of these isolates, except Leu. holzapfelii and Leu. carnosum, showed poor growth at 30℃. This confirmed their psychrotrophic characteristics. In Weissella koreensis, which was isolated at all isolation temperatures, there was a difference in the fatty acid composition of membranes between strains that could grow well at 30℃ and those that could not. These findings can contribute to the isolation of more diverse psychrotrophic strains that were not well isolated under mesophilic temperatures.

• Journal of Power Electronics
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• v.14 no.6
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• pp.1166-1177
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• 2014

A new type of topology with medium-frequency-transformer (MFT) isolation for medium voltage wind power generation systems is proposed in this paper. This type of converter is a high density power conversion system, with high performance features suitable for next generation wind power systems in either on-shore or off-shore applications. The proposed topology employs single-phase cascaded multi-level AC-AC converters on the grid side and three phase matrix converters on the generator side, which are interfaced by medium frequency transformers. This avoids DC-Link electrolytic capacitors and/or resonant L-C components in the power flow path thereby improving the power density and system reliability. Several configurations are given to fit different applications. The modulation and control strategy has been detailed. As two important part of the whole system, a novel single phase AC-AC converter topology with its reliable six-step switching technique and a novel symmetrical 11-segment modulation strategy for two stage matrix converter (TSMC) is proposed at the special situation of medium frequency chopping. The validity of the proposed concept has been verified by simulation results and experiment waveforms from a scaled down laboratory prototype.

• Microbiology and Biotechnology Letters
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• v.22 no.1
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• pp.13-17
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• 1994

We estabilished the procedure for isolation of Streptococcus salivarius subsp. thermophilus from raw milk. First, urease-producing lactic acid bacteria in raw milk were screened on the HY agar medium containing urea. Thereafter the urease-producing colonies were tested the ability to ferment maltose and to grow at43$\circ $C. We obtained about 400 maltose-negative colonies that grew at 43$\circ $C. No significant difference in carbohydrate fermentation test for isolated and type strains(S. salivarius subsp. thermophilus ATCC 19258 and ST-4) was found. And all of the isolated strains were able to ferment galactose. Furthermore, it was investigated that the cellular fatty acid profiles of isolated strains were similar to that of type strains. These results indicated that the isolated strains from raw milk were S. salivarius subsp. thermophilus. But when the isolated and type strains were incubated in 12% reconstituted skim milk at 43$\circ $C, the isolates produced lactic acid more slowly than the type strains.

• Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.259-263
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• 2012

To isolate an alginate-degrading bacterium, we conducted a single colony isolation using a solid medium containing alginate as the sole carbon source. A marine bacterium Y-4 capable of degrading alginate was isolated from seawater. The strain was identified to be Pseudoalteromonas sp., based on morphological, biochemical, 16S rDNA homology, and phylogenetic analyses. Moreover, Pseudoalteromonas sp. Y-4 exhibited alginate lyase activity in the presence of 4% alginate even though many known alginate-degrading bacteria degrade in the range of 0.5-1% alginate. The optimum culture conditions for the Y-4 strain were 2% alginate, pH 8.0, and 3% NaCl at $30^{\circ}C$. The highest alginate lyase activity was also observed under the same conditions. To our knowledge, this is the first reported isolation of a marine bacterium degrading high concentrations of alginate.

• Journal of Environmental Health Sciences
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• v.33 no.1 s.94
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• pp.16-20
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• 2007

Vibrio parahaemolyticus was investigated for analysis of distribution and antibiotic susceptibility at the markets, Seoul in 2004. The average isolation rate was 26.8%(306/1,143) and the highest rate with 64.9% was obtained in August. The isolation rates from December to April was 0.0%. It is more effective to inoculate into the enrichment medium, alkaline pepton water by swabbing a sample with a cotton ball rather than pouring mixed sample. The isolation rates were from 24.4% to 37.1% in domestic samples and from 9.8% to 26.8% in imported ones. All of the isolates were resistent to ampicillin and ticarcillin and most of them were sensitive to chloramphenicol, tetracycline, nalidixic acid, amoxicillin, ceftriaxone, streptomycin, kanamycin, trimethoprim/sulfamethoxazol, ampicillin/sulbactam, ciprofloxacin.