Silver Nanoparticles and Silver Ions: Oxidative Stress Responses and Toxicity in Potato (Solanum tuberosum L) Grown in vitro

Mozafar Bagherzadeh Homaee,Ali Akbar Ehsanpour 한국원예학회 2016 Horticulture, Environment, and Biotechnology Vol.57 No.6

Under in vitro conditions, we examined the effects of silver nanoparticles (AgNPs) and silver (Ag) ions on potato (Solanum tuberosum L.) in terms of silver accumulation, production of reactive oxygen species (ROS), oxidative stress responses, and antioxidative defense systems. At all concentrations (except at 2 mg・L-1), the amount of Ag in the shoots and roots of Ag ion-treated plantlets was significantly higher than in plantlets treated with AgNPs. In both treatments, total ROS and superoxide anions were increased at concentrations greater than 2 mg・L-1. Damage caused by oxidative stress, such as ion leakage and cell death, was significantly higher in plantlets treated with AgNPs than those treated with Ag ions. Significant increases in the activities of superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase (GR),were found in both AgNP-treated, and Ag ion-treated plantlets compared to the control. However, in AgNP-treated plantlets, GR activity was significantly decreased at 20 mg・L-1. A significant reduction in glutathione (GSH), ascorbate (ASA), and the ratios of GSH to oxidized glutathione (GSSG) and ASA to oxidized ascorbate (DHA)were observed in plantlets treated with both AgNPs and Ag ions at concentrations higher than 2 mg・L-1. Moreover, a greater decrease in GSH and ASA contents was seen in plantlets treated with AgNPs compared to those treated with Ag ions. The present study indicates that both AgNPs and Ag ion treatments impose oxidative stress on potato plantlets under in vitro conditions. Furthermore, based on plantlets’ responses to oxidative damage, the observed alteration in the activities of radical scavenging enzymes and the depletion of GSH and ASA, AgNPs seem to have higher toxicity than the equivalent mass of Ag ions.

양돈폐수 처리에 의한 포플러클론의 산화스트레스와 항산화반응

제선미 ( Sun Mi Je ),여진기 ( Jin Gi Yeo ),우수영 ( Su Young Woo ) 한국농림기상학회 2011 한국농림기상학회지 Vol.13 No.3

We studied the influence of livestock waste leachate on oxidative damage and antioxidative responses in poplar clones in August which increase the demand of antioxidants because of high temperature and high light during this period. We measured ion leakage, antioxidant enzyme activities (APX, GR), and carotenoid contents. Oxidative damage and antioxidative responses by treated livestock waste leachate in poplar clones showed various results. We divided poplar clones into three groups using the criteria based on ion leakage which represent cell damage induced oxidative stress. Eco 28, 62-10, Bonghwa1 and Dorskamp belonged to the first group in which the cell damaged level was lower than that of the control. The results suggest that this group augmented for demand of antioxidative in summer because high concentration of nitrogen induced by treatment of live stock wastes acted as environmental stress. Consequently, they failed to keep up the homeostasis of reactive oxygen species. The second group in which the cell damaged level was similar to that of the control was Suwon, 72-30 and 72-31 clones. Finally, 97-18 clone belonged to the third group in which the cell damaged level was lower than that of the control group. In this case, nitrogen treated by livestock waste leakage decreased oxidative stress. 97-18 clone was the clones with the least damage in summer oxidative stresses treated by livestock waste leakage. These results suggest that the high concentration nitrogen due to the livestock waste leakage can act differently upon the clones. We speculate that the added oxidation damage in the summer (growing season) may have an effect on the total fresh weight and also influence the purification ability for livestock waste leakage. However, further studies are needed for the confirmation.

효율적인 전기화학적 LiOH 생산을 위한 상용 바이폴라막 특성 분석

송현비,강문성,Song, Hyeon-Bee,Kang, Moon-Sung 한국막학회 2022 멤브레인 Vol.32 No.5

최근 전기자동차용 이차전지 등의 수요가 급증하면서 효율적인 리튬 화합물의 생산이 큰 주목을 받고 있다. 바이폴라막 전기투석은 친환경적이며 경제성 및 효율성이 우수한 전기화학적 리튬 화합물 생산공정으로 알려져 있다. 바이폴라막 전기투석 공정의 효율은 바이폴라막의 성능에 의해 좌우되기 때문에 바이폴라막의 선택이 매우 중요하다. 본 연구에서는 세계적으로 가장 널리 사용되고 있는 대표적인 상용 BPM인 Astom사의 BP-1E 및 Fumatech사의 FBM을 비교 분석함으로써 전기화학적 LiOH 생산을 위한 BPED 공정에 적합한 BPM의 특성을 도출하고자 하였다. 체계적인 평가를 통해 BPM의 특성중 막의 이온전달저항 및 co-ion leakage를 줄이는 것이 가장 중요하고 이러한 관점에서 BP-1E가 FBM보다 더 우수한 성능을 가지고 있음을 확인하였다.

리튬이온전지를 사용하는 ESS에서 CMV 및 누설전류의 발생원인과 저감방법에 관한 연구

김승호(Seung-Ho Kim),최형석(Hyoung-Seok Choi),김진용(Jin-Yong Kim),한아(Ah Han) 대한전기학회 2021 전기학회논문지 Vol.70 No.1

ESS(Energy Storage Systems) using lithium ion battery are rapidly increasing their capacity because they can efficiently store electrical energy in a small area with high energy density. However, 29 fire accidents have been reported in Korea for last 4 years. Up to now, the root cause of ESS fire has not been clearly defined, but some lithium ion battery manufacturer assert that the reason of fire may be caused by CMV(Common Mode Voltage) and leakage current. This study investigated the mechanism, measuring, acceptable level, and mitigation of CMV and leakage current through experimental field analysis with its corresponding simulation. The stray capacitance of IGBT module and lithium-ion battery are investigated as the cause of CMV and leakage current, and the magnitude variation of CMV and leakage current by the type of system earthing of the AC side is investigated too, then this paper suggested the use of an isolation transformer as a mitigation method. In addition, it was analyzed how the use of an isolation transformer can reduce CMV and this study proved that the installation of an isolation transformer is a complete and fundamental solution to reduce both CMV and leakage current by simulation and field measurement results. On the other hand, this study found the shape and period of the waveform of CMV and leakage current are completely identical, and prove that these two are produced by the same cause and the leakage current was also demonstrated to be lowered when the CMV was lowered. On the other hand, based on the analyzing the path of the leakage current flow in the grounded system and the non-ground systems, this study found that it was reasonable to measure CMV and leakage current on the DC side of PCS, and this was proved by P-Sim simulation and field experiments.

Dependence of Na+ leakage on intrinsic properties of cation exchange resin in simulated secondary environment for nuclear power plants

안현경,안치현,박병기,이인형 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.2

Material corrosion in nuclear power plant (NPP) is not controlled only by amine injection but also by ion exchange (IX) which is the best option to remove trace Naþ. This study was conducted to understand the Naþ leakage characteristics of IX beds packed with ethanolamine-form (ETAH-form) and hydrogen-form (H-form) resins in the simulated water-steam cycle in terms of intrinsic behaviors of four kinds of cationexchange resins through ASTM test and Vanselow mass action modeling. Naþ was inappreciably escaped throughout the channel created in resin layer. Naþ leakage from IX bed was non-linearly raised because of its decreasing selectivity with increasing Naþ capture and with increasing the fraction of ETAH-form resin. Naþ did not reach the breakthrough earlier than ETAHþ and NH4 þ due to the increased selectivity of Na þ to the cation-exchange resin (Hþ < ETAHþ < NH4 þ ≪ Naþ) at the feed composition. Naþ leakage from the resin bed filled with small particles was decreased due to the enhanced dynamic IX processes, regardless of its low selectivity. Thus, the particle size is a predominant factor among intrinsic properties of IX resin to reduce Naþ leakage from the condensate polishing plant (CPP) in NPPs

Growth, Physiology, and Abiotic Stress Response to Abscisic Acid in Tomato Seedlings

Ngoc-Thang Vu,강호민,김영식,최기영,김일섭 한국원예학회 2015 Horticulture, Environment, and Biotechnology Vol.56 No.3

The effect of abscisic acid (ABA) on growth, abiotic stress tolerance, and physiology of tomato seedlings was investigated. To examine the effect of ABA concentration on growth and abiotic stresses, six ABA concentrations (0, 10, 50, 100, 150, or 200 mg·L-1) were applied by foliar spraying once a day for 10 days. The effect of ABA application number was also studied by using different timing at one ABA concentration (100 mg·L-1) once a day for 1, 3, 5, 7, and 9 days. The effect of ABA on physiology of tomato seedlings was examined by using two concentrations (50 and 100 mg·L-1) as compared to the control (non-ABA). Foliar application of ABA decreased the growth characteristics of tomato seedlings in a concentration-dependent manner; however, no statically significant difference was observed between the 50 and 100 mg·L-1 treatments. Furthermore, although growth parameters decreased statistically with increasing number of ABA treatments, there was no difference between the 3 and 5 application treatments. Application of ABA enhanced stress tolerance (cold and drought) of tomato seedlings by delaying the starting time of wilting point in drought conditions and reducing the relative ion leakage and chilling injury index in low temperature in all treatments. The transpiration rate decreased significantly, while stomatal diffusive resistance increased significantly with increasing ABA concentration. The relative water content decreased significantly during the period without irrigation. However, relative water content increased with increasing ABA concentration. The ABA enhanced drought tolerance of tomato seedlings by delaying the start time of wilting point from day 3 in the control to day 5 and 7 in the 50 and 100 mg·L-1 treatments, respectively. Integrating this result data, we can determine the ABA’s ability to maintain of seedling quality at low temperature and water deficit condition.

Improvement of Tomato Seedling Quality under Low Temperature by Application of Silicate Fertilizer

Ngoc-Thang Vu(넉탕부),Anh-Tuan Tran(안추안트란),Thi-Tuyet-Cham Le(띠투엣참리),Jong-Kuk Na(라종국),Si-Hong Kim(김시홍),Jong-Man Park(박종만),Dong-Cheol Jang(장동철),Il-Seop Kim(김일섭) (사)한국생물환경조절학회 2017 시설원예‧식물공장 Vol.26 No.3

규산 시비가 토마토 플러그 묘소질에 미치는 영향과 묘의 저온저장시 규산의 저온장해 경감효과를 검토하였다. ‘Rapito’품종을 공시하여 30일간 32구 규격의 플러그 트레이에서 육묘한 뒤, 여섯 개의 규산 처리농도구 (8, 16, 32, 64, 128 및 256mM)를 설계하여 20일 동안 주 2회 관주 처리한 뒤, 묘소질을 대조구와 비교하였다. 처리 농도는 16mM과 32mM 처리가 초장, 엽면적, 생체중, T/R율 및 근권부 발육 등 대부분의 생육지표에서 타 처리구에 비해 양호했으며, 특히 16mM의 농도에서 가장 좋은 묘소질을 보였으나, 64mM 이상의 고농도에서는 대조구에 비해 전반적으로 생육이 억제되는 경향을 보였다. 토마토 묘의 생리적 반응에서 엽온에서는 처리구별 차이가 나타나지 않았으나, 증산율은 32mM이상의 농도 처리구에서 기공확산 저항이 증가하면서 증산율이 감소되는 경향을 보였다. 또한, 처리 횟수에 따른 효과를 검토하기 위해 16mM농도의 규산을 20일 동안 6, 10, 20회 관주처리 한 결과, 대부분의 생육지표에서 처리 횟수간에는 큰 차이가 없었으나, 무처리구에 비해 묘소질이 향상되었으며, 특히 뿌리표면적, 근장, root tip수등 근권부의 생육이 현저히 증가하였다. 아울러 규산처리가 저온저장시 토마토 묘의 저온장해를 감소시키는 효과가 있음을 확인하였다. The object of this study was to improve tomato seedling quality in low temperature(below 7, 10℃ during night time or daily mean air temperature was 18℃) by application of silicate fertilizer. Six different silicate fertilizer concentrations (8, 16, 32, 64, 128, and 256mM) or water as the control were applied to tomato seedlings twice a week for 20 days. Positive effects were observed in the growth parameters of the seedlings treated with 16 and 32mM silicate fertilizer; the most effective concentration of silicate at which seedlings showed the best performance was 16mM. However, a high concentration of silicate (256mM) caused negative effects on the growth. The transpiration rate decreased alongside with the increase of silicate concentration up to 32mM, possibly due to the increased stomatal diffusive resistance. Silicate stimulated the growth and development of tomato seedlings, resulting in increased growth parameters and root morphology. However, no significant differences were observed among treatment numbers of soil-drenching wuth the silicate (6, 10, or 20 times with 16mM) for 20 days, suggesting that silicate treatment with 6 times may be sufficient to induce the silicate effects. The application of 16mM of silicate fertilizer reduced relative ion leakage and chilling injury during low temperature storage. In addition, the seedlings treated with silicate fertilizer recovered faster than those without silicate treatment after low temperature storage.

Growth Inhibition, Seedling Damage, and Antioxidant Change of Cucumber Plug-transplants in Response to UV Spectra and Irradiation Timing

Sung-Woo Jeong(정성우),Joong-Choon Park(박중춘),Moo-Ryong Huh(허무룡) 한국원예학회 2009 원예과학기술지 Vol.27 No.1

자외선의 파장과 조사주기가 오이 플러그묘의 생육억제, 유묘장해, 그리고 항산화 물질의 함량 변화에 미치는 영향을 구명하고자 본 실험을 수행하였다. B-UV(274-400㎚)의 처리는 조사주기와 관계없이 초장과 절간길이를 현저히 억제시켰다. 그러나 이온누출, 지질과산화, 그리고 엽록소의 유의적인 변화를 초래했으며, 결국 잎의 황백화와 주름현상을 나타내었다. 한편, F-UV(286-400㎚)의 처리는 오이 유묘에 생리장해를 초래하지 않았고 초장과 절간장을 각각 24%와 21% 억제시켜 유의성이 있는 것으로 나타났고, 아울러 ascorbic acid와 총 페놀 화합물의 함량을 증진시켰다. 이는 F-UV 처리에 대한 항산화 물질의 증가로 판단되며, 새로운 도장억제 처리기술의 가능성을 제시해주었다. The objectives of this study were to determine the effect of UV spectra (B-UV: 274-400 ㎚ or F-UV: 286-400 ㎚) and irradiation timing (at day or night) on growth inhibition, seedling damage, and antioxidant change in cucumber (Cucumis sativus L. cv. Garakmanchun) plug-transplants. B-UV (274-400 ㎚) significantly inhibited plant height and internode length; however, it increased ion leakage and lipid peroxidation, and decreased photosynthetic pigments, resulting in leaf necrosis and wrinkle regardless of irradiation timing. While F-UV (286-400 ㎚) did not cause plant damage such as leaf necrosis and wrinkle regardless of irradiation timing, it significantly inhibited plant height and internode length by 24% and by 21%, respectively and simultaneously increased the content of ascorbic acid and total phenolic compounds. Our results suggest that F-UV irradiation may be desirable for controlling the over-growth in cucumber plug-transplants.

Overexpression of AtSZF2 from Arabidopsis Showed Enhanced Tolerance to Salt Stress in Soybean

( Mi-jin Kim ),( Hye Jeong Kim ),( Jung Hun Pak ),( Hyun Suk Cho ),( Hong Kyu Choi ),( Ho Won Jung ),( Dong Hee Lee ),( Young-soo Chung ) 한국육종학회 2017 Plant Breeding and Biotechnology Vol.5 No.1

Plants have adapted to environmental challenges by expressing many plant genes in response to the stresses. Among those genes, CCCH zinc finger proteins are involved in abiotic and biotic stresses. Transgenic soybean plants overexpressing AtSZF2 were produced to investigate that its ectopic overexpression enhanced salt stress tolerance by Agrobacterium-mediated transformation using half-seed explants. Sixteen transgenic lines were chosen to analyze for T-DNA insertion and transcription levels, and most of them were confirmed as positive. In further analysis with Southern blot, stable transformation event and copy number were confirmed. Following high salinity stress on the detached leaf and whole plant of two transgenic lines (#4 and #6) revealed that the ectopic expression of AtSZF2 was correlated with stress tolerance in phenotype, ion leakage and chlorophyll content with statistical significance. In another test with 20% PEG treatment, similar tolerance of transgenic plants was observed with lower ion leakage and higher chlorophyll content, indicating that the damage of cell membrane was prevented in transgenic plants. Finally, expression of various abiotic stress-responding genes was detected by reverse transcriptase and quantitative real-time PCR analysis with the transgenic plants. It could be proposed that introduction of AtSZF2 resulted in the modulation of ABA/stress responsive gene expression in transgenic soybean plants and make them tolerant against salt stress. Considering soybean as a salt-sensitive crop and importance of salt stress tolerance in specific farming region, the introduction of AtSZF2 may provide an approach for crop improvement in soybean breeding.

수확 후 고온처리가 참외의 저온장해 완화와 저장성 향상에 미치는 영향

강호민(Ho-Min Kang),박권우(Kuen-Woo Park),김일섭(Il-Sop Kim) (사)한국생물환경조절학회 2005 시설원예‧식물공장 Vol.14 No.3

저장전 고온처리(38℃, 48시간)는 참외의 당도, 산도, 비타민 C의 함량과 α-tocopherol 활성을 높였으며, 3℃의 MA저장중 생체중 감소 이산화탄소, 에틸렌그리고 아세트알데히드 발생량을 낮게 유지시켰다. 또한 저장후 외관상 품질, 경도, 당도, 산도, 비타민 C, α-tocopherol 활성 등 내적품질이 고온처리한 참외에서 높은 수준을 유지하였는데 특히 저온장해정도를 알 수 있는 이온용출량이 고온처리구에서 낮아 수확후 고온처리로 저온장 해가 완화되었음을 알 수 있었다. 고온처리를 하지 않은 대조구는 저장 25일부터 Alternaria rot이 발견되었으나 고온처리구는 저장 종료일인 39일까지 부패가 발견되지 않았으며 외관상 품질에 대한 저장일수로 세운 회귀식에 의하면 저장수명이 고온처리구에서 8일 이상 연장되었다. 참외의 경우 저장전 38℃의 낮은 고온에서 장시간 열처리를 함으로써 살균효과 저온장해 완화효과와 더불어 수명연장까지 얻을 수 있었다. Oriental melons hold at 38℃ for 48 hours before storage increased their soluble solid, titratable acidity, vitamin C contents and α-tocopherol activity. These heat treated oriental melons maintained lower production of carbon dioxide, ethylene and acetaldehyde and loss of fresh weight than untreated them, called control, during 3℃ MA storage. After 39 days in storage, the last day of storage, visual quality and internal quality, such as firmness, soluble solid, titratable acidity, vitamin C and α-tocopherol activity, showed higher in heat treated oriental melons. Especially, Ion leakage of flesh, index of chilling injury, increased remarkably in control, so that heat treatment had to alleviate chilling injury in oriental melon. Moreover, while Alternaria rot was shown in control plot after 25 days in 3℃ MA storage, oriental melons treated heat were not appeared any decomposition after 39 days in 3℃ MA storage. As storage life of oriental melon was calculated by regression equation between visual quality and days in storage, that was longer 8 days in heat treated than control. Consequently, heat treatment that was mild, 38℃ and long period, 48 hours, executed before storage, sterilized surface alleviated chilling injury and lengthened storage life in oriental melons.