• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2243-2244
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• 2013

• 한국자원식물학회지
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• 제17권2호
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• pp.75-81
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• 2004

본 연구는 산림 수목 종자를 대상으로 다양한 초저온 동결 조건을 적용하고, 초저온 저장 후에 나타나는 종자의 발아 특성 및 유묘의 생장 특성 조사하기 위해 수행되었다. 유리화 과정을 기초로 한 초저온 저장은 다릅나무 종자의 발아율을 크게 감소시켰으나, 초저온 저장 전 동결보호제 처리와 초저온 저장 후의 빠른 해빙은 종자의 발아율 감소를 완화시켰다. 초저온 저장 전 동결보호제 노출 시간은 종자의 발아율에 영향을 주었다. 즉 동결보호제 노출시간이 길어짐에 따라 종자의 발아율은 감소하였다. 그러나 초저온 저장 기간은 종자의 발아율에 영향을 주지 않았다. 또한 동결보호제의 노출 시간과 초저온 저장 기간은 유묘의 생장 특성에 영향을 주지 않았다. 따라서 수목 종자의 초저온 저장은 조직의 손상이나 변형이 없이 장기간 저장할 수 있는 현지 외 보존 기술로 적절하다고 판단된다. 그러나 산림 종자의 보다 효율적인 초저온 저장을 위해서는 각 수종의 종자 특성에 맞는 동결보호제 및 처리 기술이 개발되어야 할 것으로 판단된다.

• Current Photovoltaic Research
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• 제2권1호
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• pp.1-7
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• 2014

We developed a method of growing thin Si film at $600^{\circ}C$ by hot wire CVD using a very thin large-grained poly-Si seed layer for thin-film Si solar cells. The seed layer was prepared by crystallizing an amorphous Si film by vapor-induced crystallization using $AlCl_3$ vapor. The average grain size of the p-type epitaxial Si layer was about $20{\mu}m$ and crystallographic defects in the epitaxial layer were mainly low-angle grain boundaries and coincident-site lattice boundaries, which are special boundaries with less electrical activity. Moreover, with a decreasing in-situ boron doping time, the mis-orientation angle between grain boundaries and in-grain defects in epitaxial Si decreased. Due to fewer defects, the epitaxial Si film was high quality evidenced from Raman and TEM analysis. The highest mobility of $360cm^2/V{\cdot}s$ was achieved by decreasing the in-situ boron doping time. The performance of our preliminary thin-film solar cells with a single-side HIT structure and $CoSi_2$ back contact was poor. However, the result showed that the epitaxial Si film has considerable potential for improved performance with a reduced boron doping concentration.

• Molecules and Cells
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• 제42권10호
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• pp.711-720
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• 2019

Sink strength optimizes sucrose import, which is fundamental to support developing seed grains and increase crop yields, including those of rice (Oryza sativa). In this regard, little is known about the function of vacuolar invertase (VIN) in controlling sink strength and thereby seed size. Here, in rice we analyzed mutants of two VINs, OsVIN1 and OsVIN2, to examine their role during seed development. In a phenotypic analysis of the T-DNA insertion mutants, only the OsVIN2 mutant osvin2-1 exhibited reduced seed size and grain weight. Scanning electron microscopy analysis revealed that the small seed grains of osvin2-1 can be attributed to a reduction in spikelet size. A significant decrease in VIN activity and hexose level in the osvin2-1 spikelets interfered with spikelet growth. In addition, significant reduction in starch and increase in sucrose, which are characteristic features of reduced turnover and flux of sucrose due to impaired sink strength, were evident in the pre-storage stage of osvin2-1 developing grains. In situ hybridization analysis found that expression of OsVIN2 was predominant in the endocarp of developing grains. A genetically complemented line with a native genomic clone of OsVIN2 rescued reduced VIN activity and seed size. Two additional mutants, osvin2-2 and osvin2-3 generated by the CRISPR/Cas9 method, exhibited phenotypes similar to those of osvin2-1 in spikelet and seed size, VIN activity, and sugar metabolites. These results clearly demonstrate an important role of OsVIN2 as sink strength modulator that is critical for the maintenance of sucrose flux into developing seed grains.

• Journal of Plant Biotechnology
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• 제47권4호
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• pp.330-336
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• 2020

Ex-situ conservation of the ornamental and medicinal orchid, Coelogyne stricta, was performed by mass propagation using seed culture. Propagation stages were optimized using full- and half-strength solidified MS medium with different phytohormones. Maximum seed germination (88 ± 0.5% over 6 weeks of culture) was achieved on half-strength MS medium supplemented with 15% coconut water. Maximum shoot numbers were found on full-strength MS medium supplemented with 1 mg/L BAP, 2 mg/L Kinetin, and 10% coconut water, while the longest root was developed on full-strength MS medium with 1.5 mg/L IBA. A 2:1:1 combination of coco-peat, pine bark, and sphagnum moss was found to be a suitable potting mixture resulting in 80% seedling survivability. The cytotoxic activity of extracts of both wild plants and in vitro-developed protocorms was determined using an MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay on a cervical cancer cell line. The wild plant extract inhibited the growth of 41.99% of cells, showing that this extract has moderate cytotoxic activity toward cervical cancer cells.

• 한국미생물·생명공학회지
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• 제51권4호
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• pp.416-424
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• 2023

Replacing synthetic additives to preserve food products with natural antimicrobial compounds needs to be considered due to public health. In the present study, the phenolic extract from mango seed kernel (MSK) with the total phenolic content (TPC) value of 5300 ± 380 mg gallic acid equivalent (GAE)/L was used for evaluating the antimicrobial properties against five types of bacterial strains, including Listeria monocytogenes, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhimurium in vitro. This extract was also used for in situ method on the storage of Pangasianodon hypophthalmus fish fillets. The minimum inhibitory concentration (MIC) values for all tested strains were determined at an average concentration of 1325 mg GAE/L. Furthermore, the minimum bactericidal concentration (MBC) values of E. coli, S. aureus, and S. typhimurium were seen at 5300 mg GAE/L, while the extract did not show eliminations in the growth of the remaining strains. The bacterial inhibition speed of the extract illustrated that the concentration equal MIC value eliminated S. typhimurium growth after 24 h, the 4 times MIC value had remarkable effects on S. aureus growth after the 9 h of incubation, and 24 h of incubation for E. coli, L. monocytogenes, P. aeruginosa. Additionally, the MSK extract could inhibit the growth of P. aeruginosa on fish fillets in 4 days of storage. These results provide important evidence for the utilization of MSK as a natural source of antimicrobial agents in food products.

• 한국결정성장학회지
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• 제29권6호
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• pp.383-388
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• 2019

개선된 열탄소환원법으로 합성된 금속불순물함량 1 ppm 이하의 고순도 SiC 미립 분말을 이용하여 2,100℃ 이상고온의 RF 가열 PVT 장치에서 SiC 단결정을 성장시켰으며, In-situ x-ray 이미지 분석을 통해 성장과정 중 분말의 승화거동 및 단결정 성장거동을 관찰하였다. SiC 분말은 단결정 성장의 공급원으로 온도가 높은 외곽 부분부터 소진되고 graphite 잔여물이 남았다. 성장 중 원료의 흐름은 가운데 부분으로 집중되었으며 SiC 단결정의 성장거동에도 영향을 미쳤는데, 이는 미립분말로 인한 도가니 내부 온도분포 차이가 원인으로 예상되었다. 단결정 성장이 완료된 후, 단결정 잉곳을 1 mm 두께의 단결정 기판으로 절단하고 또한, 잉곳에서 얻어진 단결정 기판은 전반적으로 짙은 황색의 4H -SiC가 관찰되었으며, 외곽에 일부 발생한 다결정은 시드결정을 시드홀더에 부착하는 과정에서 혼입된 기포층과 같은 불순물 혼입이 원인으로 사료된다.

• Journal of Forest and Environmental Science
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• 제32권3호
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• pp.311-322
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• 2016

Since forest trees form the basis of forest ecosystem, their prolong subsistence is crucial for various flora and fauna. The foremost challenges to sustain the forest ecosystem comprise of the declining forest tree population accompanied with structural changes due to afforestation and exploitation of forest area, environment changes, pests, pollution, and introgressive hybridization. For ex situ conservation approach, in vitro techniques encompass basic role for conserving tree genetic resources, predominantly where natural propagules like recalcitrant seed might not be appropriate for long-term conservation. The practice includes restricted growth techniques, conventional micropropagation, production and storage of synthetic seeds, and cryopreservation. Even though these practices have been applied chiefly to herbaceous species, but recently, woody species were also focused upon. Key conceptions, challenges and techniques for forest tree seed conservation are discussed briefly in this review with special emphasis on some successful cryopreservation approaches for long-term storage.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.37-37
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• 2018

We use two different methods for laboratory propagation from seed of lady's slipper orchid(Cypripedium macranthos Sw.); immature seed which also called green capsule or fully mature seed about 120~130 days from pollination. In green capsule culture, the seed pods should be collected within precisely right time. The right time of seed collection could be diverse under the wether conditions or nutritional factors of the plants. In fully matured seed culture, the more complicated procedures are needed to break the dormancy of the seed; thermal or chemical treatment. The seedlings in this study were easily germinated from immature seeds in Harvais medium; 53 days after pollination(DAP) in Cypripedium pubescens, DAP 65 in C. parviflorum and C. macranthos. The germinated seedlings were transplanted to hormone free media immediately to avoid abnormal growth of seedlings. When the seedlings have roots with a minimum length of around 2-3cm and have visible dormant buds, the seedlings were removed from the flask and stored in refrigerator for vernalization. To examine the correlation of seedlings and maternal plants, the 125 seedlings of C. macranthos were transplanted in the soil bed at a distance of 20-100 cm from mother plants on April 20. The survival rate of seedlings were 92% in 20 cm distance from the ripe plants, and 56 % in 100 cm distance. The seedlings which were transplanted near mother plants showed vigorous growth in plant height, leaf width, and especially dormant buds. Considering the existence of mycorrhiza which is a symbiotic association between a fungus and the roots of a orchid vascular, the various fungus from mother plants could affect the growth of the seedlings. These results indicate the possibility of high and stable production and practical industrialization of endangered lady's slipper orchids.

• 한국물환경학회지
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• 제22권2호
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• pp.300-307
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• 2006

The combined SHARON (Single reactor system for High ammonium Removal Over Nitrite)-ANAMMOX (Anaerobic ammonium oxidation) reactor were operated in mesophilic condition ($35^{\circ}C$). In this study, microbial granulation and characteristics of SHARON and ANAMMOX sludges were investigated using settling test, Scanning Electron Microscopy (SEM) and Fluorescence In Situ Hybridization (FISH). In SHARON reactor, Aerobic granulation with diameter of 1.5~2.5 mm was accomplished but aerobic granulation was weaker than anaerobic granular sludge. Initial seed sludge of ANAMMOX reactor was used as attached media for biofilm growth. ANAMMOX sludge was more compact and rounder rather than seed sludge. Though ANAMMOX sludge has high activity, it has lower settling ability than the seed granule. The color of ANAMMOX sludge was changed from dark to redish brown granular with diameter of 1~2 mm. In FISH of ANAMMOX sludge, high fraction of Candidatus B. stuttgartiensis which paid great role of nitrogen conversion was detected. Also, FISH results reveals that ANAMMOX bacteria inhabit at inner parts near surface, having advantages in utilization of substrates and protection from oxygen inhibition.