겨울철 자연환경에 노출된 문주란 잎의 엽록소형광과 항산화 효소 활성에 관한 연구

오순자 ( Soon Ja Oh ),고석찬 ( Seok Chan Koh ) 한국환경생물학회 2004 환경생물 : 환경생물학회지 Vol.22 No.1

겨울철 저온에 의한 식물의 반응 및 생리적 상태를 확인하기 위해 문주란 (Crinum asiaticum var. japonicum)을 대상으로 엽록소형광과 항산화효소 활성의 변화를 조사하였다. O-J-I-P 곡선을 분석한 결과 겨울철에 J, I, P-단계에서의 형광세기가 현저하게 감소하였다. 문주란 잎의 광계Ⅱ의 광화학적 효율, 즉 Fv/Fm은 겨울철의 온도변화 추이와 유사하게 낮은 값을 나타내어 겨울철 저온이 스트레스 요인으로 작용하는 것으로 보인다. 그리고, 겨울철에 superoxide dismutase, ascorbate peroxidase, peroxidase활성이 다소 증가하였으나 catalase 활성은 여름철에 비하여 크게 낮았다. 이러한 결과는 겨울철의 Fv/Fm의 감소와 함께 문주란이 겨울철 저온에 의해 산화적 스트레스에 처해 있게되며 세포사멸이 일어나는 것으로 해석된다. Chlorophyll fluorescence and antioxidative enzyme activity were investigated from leaves of Crinum asiaticum var. japonicum under the natural condition in winter, in order to monitor plant response and physiological states such as vitality, productivity and so on. In the O-J-I-P transients, the fluorescence intensity of J, I, P-step decreased remarkably depending on temperature drop in winter. The photochemical efficiencies of PSⅡ, Fv/Fm, were significantly low in late winter with decrease of Fm. These results indicate that Crinum plants were affected by seasonal drop of temperature. The catalase activity significantly decreased depending on temperature drop in winter. However, the activity of superoxide dismutase ascorbate peroxidase and peroxidase slightly increased in winter while some isoenzymes appeared in winter. These results, with the remarkable decrease of Fv/Fm in winter, represent that Crinum plants were exposed to oxidative stress and subsequently damaged leading to cell death.

겨울철 저온스트레스에 의한 문주란 잎의 항산화효소 활성과 O-J-I-P 곡선 패턴

오순자 ( Soon Ja Oh ),고석찬 ( Seok Chan Koh ) 한국환경생물학회 2005 환경생물 : 환경생물학회지 Vol.23 No.2

본 연구는 환경요인의 변화, 특히 겨울철 저온이 식물체에 미치는 영향을 정량적으로 밝히기 위해, 저온감수성 식물인 문주란을 대상으로 겨울철 일주기에 있어서 항산화효소 활성과 O-J-I-P 곡선의 변화를 조사하였다. 겨울철의 superoxide dismutase와 peroxidase의 활성은 여름철에 비해 다소 증가하였다. 특히, peroxidase는 겨울철 새벽과 밤에 높은 활성을 보였으며 초겨울에만 특이적으로 검출되는 isoenzyme들로 관찰할 수 있었다. 또한 겨울철 문주란 잎의 O-J-I-P곡선에서 J, I, P-단계의 형광세기가 여름철에 비해 현저하게 감소하였다. 그리고, O-J-I-P 곡선으로부터 산출된 주요 형광변수들 중에 Fm과 Φpo는 겨울철 저온에 노출되는 기간이 길어짐에 따라 각각 30%와 50%로 감소하였으며, ABS/RC는 초겨울보다는 늦은 겨울에 2배 정도 증가하였다. The diurnal and seasonal variations of antioxidative enzyme activity and the O-J-I-P transients were investigated from the leaves of Crinum asiaticum var. japonicum under winter stress in natural habitat, in order to diagnose quantitatively physiological states of plants under stresses. The activities of superoxide dismutase and peroxidase increased slightly in winter. Especially, peroxidase acitivity was higher at dawn and night in winter and some isoforms were detected only in early winter. In the O-J-I-P transients, the fluorescence intensity of J, I, P steps decreased significantly in winter season, contrary to its high value in summer season. Of the chlorophyll fluorescence parameters derived from the O-J-I-P transients, Fm and φpo decreased with the increase of ABS/RC depending on temperature drop in winter.

카드뮴 스트레스에 대한 수생식물 5종의 엽록소형광 반응

오순자 ( Soon Ja Oh ),진국림 ( Kook Lhim Zhin ),고석찬 ( Seok Chan Koh ) 한국환경과학회 2009 한국환경과학회지 Vol.18 No.12

연구논문 : 식물정화를 위한 중금속 내성 작물의 선발과 수수-수단그라스교잡종의 구리와 아연 흡수능력

오순자 ( Soon Ja Oh ),고석찬 ( Seok Chan Koh ) 한국환경과학회 2015 한국환경과학회지 Vol.24 No.11

As essential trace elements, copper and zinc play important roles in many physiological events in plants. In excess, however, these elements can limit plant growth. This study selected a heavy metal-tolerant plant by analyzing seed germination and biomass of alfalfa (Medicago sativa), canola (Brassica campestris subsp. napus var. nippo-oleifera), Chinese corn (Setaria italica), and a sorghum-sudangrass hybrid (Sorghum bicolor × S. sudanense), and determined heavy metal uptake capacity by analyzing biomass, chlorophyll a fluorescence, and heavy metal contents under high external copper or zinc levels. The seed germination rate and biomass of the sorghum-sudangrass hybrid were higher under copper or zinc stress compared to the other three plants. The plant biomass and photosynthetic pigment contents of the sorghum-sudangrass hybrid seedlings were less vulnerable under low levels of heavy metals (≤ 50 ppm copper or ≤ 400 ppm zinc). The maximum quantum yield of PSII (Fv/Fm) and the maximum primary yield of PSII (Fv/Fo) decreased with increasing copper or zinc levels. Under high copper levels, the decline in Fv/Fm was caused only by the decline in Fm, and was accompanied by an increase in non-photochemical quenching (NPQ). The Fv/Fm declined under high levels of zinc due to both a decrease in the maximum fluorescence (Fm) and an increase in the initial fluorescence (Fo), and this was accompanied by a marked decrease in photochemical quenching (qP), but not by an increase in NPQ. Accumulations of copper and zinc were found in both aboveand below-ground parts of plants, but were greater in the below-ground parts. The uptake capacity of the sorghum-sudangrass hybrid for copper and zinc reached 4459.1 mg/kg under 400 ppm copper and 9028.5 mg/kg under 1600 ppm zinc. Our results indicate that the sorghum-sudangrass hybrid contributes to the in situ phytoremediation of copper or zinc polluted soils due to its high biomass yield.

엽록소형광분석을 이용한 담수산 클로렐라(Chlorella vulgaris)에 미치는 중금속의 영향 평가

오순자 ( Soon Ja Oh ),고석찬 ( Seok Chan Koh ) 한국환경과학회 2015 한국환경과학회지 Vol.24 No.12

The response of the freshwater microalga, Chlorella vulgaris, to heavy metal stress was examined based on chlorophyll fluorescence analysis to assess the toxic effects of heavy metals in freshwater ecosystems. When toxic effects were analyzed using regular chlorophyll fluorescence analysis, photosystem II activity(Fv/Fm) decreased significantly when exposed to Cu2+ and Hg2+ for 12 h, and decreased in the order of Hg2+ > Cu2+ > Cd2+ > Ni2+ when exposed for 24h. The effective photochemical quantum yield(Φ′PSII), chlorophyll fluorescence decrease ratio(RFd), minimal fluorescence yield(Fo), and non-photochemical quenching(NPQ), but not photochemical quenching(qP), responded sensitively to Hg2+, Cu2+, and Cd2+. These results suggest that Fv/Fm, as well as Φ′PSII, RFd, Fo, and NPQ could be used to assess the effects of heavy metal ions in freshwater ecosystems. However, because many types of heavy metal ions and toxic compounds co-occur under natural conditions, it is difficult to assess heavy metal toxicity in freshwater ecosystems. When Chlorella was exposed to heavy metal ions for 12 or 24h, Fv/Fm and maximal fluorescence yield(Fm) changed in response to Hg2+ and Cu2+ based on image analysis. However, assessing quantitatively the toxic effects of several heavy metal ions is challenging.

제주도 자생 참나무과 식물의 대기 중 CO2 흡수 능력의 비교분석

오순자 ( Soon Ja Oh ),신창훈 ( Chang Hoon Shin ),김철수 ( Chul Soo Kim ),강희석 ( Hee Suk Kang ),강경민 ( Kyeng Min Kang ),양윤희 ( Yun Hi Yang ),고석찬 ( Seok Chan Koh ) 한국환경과학회 2012 한국환경과학회지 Vol.21 No.1

The rate of photosynthesis (A) of leaves from 10 plant species (6 evergreen and 4 deciduous) of the family Fagaceae was measured using a portable photosynthesis analyzer, to examine which species take up CO2 most efficiently. Of the evergreen species, the photosynthetic rate of Castanopsis cuspidata var. sieboldii was highest, and remained above 82.1~106.4 μmol kg-1s-1 from July to November. Of the deciduous species, the photosynthetic rate of Quercus acutissima was higher than that of the other three species, and remained high at 83.5~116.6 μmol kg-1s-1 from September to November. The photosynthetic rate of the 10 species was positively correlated with stomatal conductance (gs) and transpiration rate (E). However, there was no correlation between photosynthetic rate and intercellular CO2 concentration (Ci), although there was a positive correlation just in three species (Q. gilva, Q. acutissima and Q. glauca). These results suggest that the CO2 fixation capacity of C. cuspidata var. sieboldii, an evergreen species, and Q. acutissima, a deciduous species, is significantly higher than that of the other species examined, and that photosynthesis is regulated by both stomatal conductance and transpiration. Therefore, C. cuspidata var. sieboldii and Q. acutissima may be valuable for the evaluation of carbon uptake in urban green spaces as well as in afforested areas.

담수산 클로렐라(Chlorella vulgaris)의 수은 스트레스에 대한 엽록소형광 반응

오순자 ( Soon Ja Oh ),고석찬 ( Seok Chan Koh ) 한국환경과학회 2013 한국환경과학회지 Vol.22 No.6

The response of the freshwater microalga Chlorella vulgaris to mercuric ion (Hg2+) stress was examined using chlorophyll a fluorescence image analysis and O-J-I-P analysis as a way to monitor the toxic effects of mercury on water ecosystems. The levels of photosynthetic pigments, such as chlorophyll a and b and carotenoids, decreased with increasing Hg2+ concentration. The maximum photochemical efficiency of photosystem Ⅱ(Fv/Fm) changed remarkably with increasing Hg2+ concentration and treatment time. In particular, above 200 μM Hg2+, considerable mercury toxicity was seen within 2 h. The chlorophyll a fluorescence transient O-J-I-P was also remarkably affected by Hg2+; the fluorescence emission decreased considerably in steps J, I, and P with an increase in Hg2+ concentration when treated for 4 h. Subsequently, the JIP-test parameters (Fm, Fv/Fo, RC/CS, TRo/CS, ETo/CS, ΦPO, ΨO and ΦEO) decreased with increasing Hg2+ concentration, while N, Sm, ABS/RC, DIo/RC and DIo/CS increased. Therefore, a useful biomarker for investigating mercury stress in water ecosystems, and the parameters Fm, ΦPO, ΨO, and RC/CS can be used to monitor the environmental stress in water ecosystems quantitatively.

아열대성 식물 4종의 엽록소형광과 항산화효소 활성의 일주기적 변화

오순자 ( Soon Ja Oh ),고창효 ( Chang Hyo Goh ),고석찬 ( Seok Chan Koh ) 한국환경과학회 2007 한국환경과학회지 Vol.16 No.5

두릅나무과 식물의 SOD 활성과 광계 2 의 광화학적 효율에 미치는 온도 스트레스와 Paraquat 의 영향

오순자(Soon Ja Oh),고정군(Jung Goon Koh),김응식(Eung Sik Kim),오문유(Moon You Oh),고석찬(Suck Chan Koh) 한국환경생물학회 1999 환경생물 : 환경생물학회지 Vol.17 No.2

The effects of temperature stress and paraquat on the superoxide dismutase(SOD) activity and the photochemical efficiency of photosystem Ⅱ were studied in the leaves of Araliaceae plants. The SOD activity of Acanthopanax koreanum leaf discs increased at 4℃ and 28℃, and increased significantly at 4℃, 28℃ and 35℃ in the presence of paraquat. However, the SOD activity of Dendropanax morbifera leaf discs decreased at 4℃, 28℃ and 35℃ regardless of paraquat treatment. The photochemical efficiency of photosystem Ⅱ, Fv/Fm, of leaf discs of A. koreanum and D. morbifera fell remarkable at 35℃. IN the presence of paraquat, the Fv/Fm values fell slightly at 4℃ in A. koreanum leaf discs and at 35℃, in D. morbifera leaf discs. These results indicate that A. koreanum plants are more resistant to temperature stress or oxidative stress than D. morbifera plants although their photochemical efiiciency falls slightly at 4℃ in the presence of paraquat.

차나무, 동백나무, 귤나무 잎에서 엽록소 형광 및 CO2 흡수능의 비교 분석

오순자 ( Soon Ja Oh ),이진호 ( Jin Ho Lee ),고광섭 ( Kwang Sup Ko ),고석찬 ( Seok Chan Koh ) 한국환경생물학회 2012 환경생물 : 환경생물학회지 Vol.30 No.2

본 연구는 차나무(Camellia sinensis L.)와 동백나무(C, japonica L.), 제주지역의 주요 과수작물인 귤나무(Citrus unshiu M.) 잎을 대상으로 엽록소형광과 CO2 흡수능을 비교 분석하여 탄소흡수원으로서의 가치를 평가하고자하였다. 차나무의 CO2 고정율은 같은 과의 동백나무보다 높고 과수작물인 귤나무와 유사하였다. 기공전도도 (gs)는 3종 모두 새벽에는 높고 이후 저녁 시간까지 계속하여 감소하였다. 엽육 내 CO2 농도 (Ci)는 3종 모두 새벽 (06:00)에 높고 낮에 감소하였다가 저녁에 다시 증가하는 경향을 보였으며, 잎의 증산율 (E)은 낮 시간에 높아 졌다가 저녁에 감소하였다. 차나무에서 광계II의 광화학적 효율(Fv/Fm)은 낮시간에 다소 낮아졌다가 저녁에 다시 증가하는 양상을 보였다. 이러한 낮시간의 Fv/Fm 감소는 광억제의 결과로 보이며 그 감소폭이 동백나무보다 적어 빛이나 고온 등에 내성을 가지고 있음을 알 수 있다. 엽면적당 활성상태의 반응중심의 상대적 밀도를 의미하는 RC/CS는 3종 모두 낮시간에 감소하였다. ABS/RC, TRo/RC, ETo/RC와 DIo/RC는 차나무와 동백나무에서 낮시간에 증가하였으며, 귤나무에서도 낮시간에 증가하였으나 유의성이 없는 것으로 나타났다. 일동화율은 차나무가 320.1 mmol m-2 d-1로 가장 높았으며, 귤나무와 동백나무는 각각 292.5 mmol m-2 d-1와 244.8 mmol m-2 d-1로 나타났다. 이상의 결과를 토대로 차나무는 광합성율이 높고 낮 시간의 광억제도 낮을 뿐만 아니라, 귤나무보다 수분요구량이 낮고 수분이용효율은 높아 탄소흡 수원으로서 유용한 작물수종인 것으로 보인다. The chlorophyll fluorescence and photosynthetic CO2 fixation capacity of leaves from three major crop trees found on Jeju Island, Camellia sinensis L., Camellia japonica L., and Citrus unshiu M., were analyzed. The photosynthetic CO2 fixation rate of C. sinensis was similar to that of C. unshiu, and much higher than that of C. japonica which belongs to the same genus. Stomatal conductance in the three species was high at dawn and low during daytime. The intercellular CO2 concentration of the three species was also high at dawn and decreased at midday. The transpiration rate showed an opposite trend from the intercellular CO2 concentration. The photochemical efficiencies of PSII (Fv/Fm) in C. sinensis were slightly lower at midday compared to the level at dawn and/or dusk. The decline in Fv/Fm of C. sinensis at midday was much smaller than that of C. japonica. These results indicate that C. sinensis is better acclimated to high levels of radiation under natural conditions in late summer, although its PSII reaction center was inhibited by strong radiation. Of the chlorophyll fluorescence parameters in the species, the RC/CS decreased significantly while the ABS/RC, TRo/RC, ETo/RC, and DIo/RC increased significantly at midday in late summer. However, C. unshiu did not show significant changes in these values depending on the time of day. Among the three species, the daily CO2 fixation rate in C. sinensis (320.1 mmol m-2 d-1) was the highest, followed by that of C. unshiu (292.5 mmol m-2 d-1) and C. japonica (244.8 mmol m-2 d-1). Thus, C. sinensis may be a valuable crop tree in terms of the uptake of CO2 under natural field conditions.