• Bulletin of the Korean Chemical Society
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• v.27 no.11
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• pp.1801-1808
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• 2006

The interaction between whey carrier protein $\beta$-lactoglobulin type A and B (BLG-A and -B) and 2,2'-bipyridin n-hexyl dithiocarbamato Pd(II) nitrate (BPHDC-Pd(II)), a new heavy metal complex designed for anticancer property, was investigated by fluorescence spectroscopy combined with chemometry and circular dichroism (CD) techniques. A strong fluorescence quenching reaction of BPHDC-Pd(II) to BLG-A and -B was observed. Hence, BPHDC-Pd(II) complex can be bound to both BLG-A and -B, and quench the fluorescence spectra of the proteins. The quenching constant was determined using the modified Stern-Volmer equation. The binding parameters were evaluated by fluorescence quenching method. The results of binding study provided evidences presence of two and three sets of binding sites on the BLG-B and -A, respectively, for BPHDC-Pd(II) complex. Using fluorescence spectroscopy and chemometry, the ability of BLG-A and -B to form an intermediate upon interaction with BPHDC-Pd(II) complex was assessed. CD studies displayed that under influence of different concentrations of BPHDC-Pd(II) complex, the regular secondary structure of BLG-B had no significant changes, whereas for BLG-A a transition from $\alpha$-helix to $\beta$-structure was appeared. The results for both of BLG-A and -B displayed that BPHDC-Pd(II) complex can induce a conformational transition from the native form to an intermediate state with a slightly opened conformation, which is detectable with chemometry analyses.

• The Plant Pathology Journal
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• v.32 no.4
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• pp.300-310
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• 2016

Pathogen infection in plants induces complex responses ranging from gene expression to metabolic processes in infected plants. In spite of many studies on biotic stress-related changes in host plants, little is known about the metabolic and phenotypic responses of the host plants to Pseudomonas cichorii infection based on image-based analysis. To investigate alterations in tomato plants according to disease severity, we inoculated plants with different cell densities of P. cichorii using dipping and syringe infiltration methods. High-dose inocula (${\geq}10^6cfu/ml$) induced evident necrotic lesions within one day that corresponded to bacterial growth in the infected tissues. Among the chlorophyll fluorescence parameters analyzed, changes in quantum yield of PSII (${\Phi}PSII$) and non-photochemical quenching (NPQ) preceded the appearance of visible symptoms, but maximum quantum efficiency of PSII ($F_v/F_m$) was altered well after symptom development. Visible/near infrared and chlorophyll fluorescence hyperspectral images detected changes before symptom appearance at low-density inoculation. The results of this study indicate that the P. cichorii infection severity can be detected by chlorophyll fluorescence assay and hyperspectral images prior to the onset of visible symptoms, indicating the feasibility of early detection of diseases. However, to detect disease development by hyperspectral imaging, more detailed protocols and analyses are necessary. Taken together, change in chlorophyll fluorescence is a good parameter for early detection of P. cichorii infection in tomato plants. In addition, image-based visualization of infection severity before visual damage appearance will contribute to effective management of plant diseases.

• Korean Journal of Environmental Agriculture
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• v.20 no.2
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• pp.93-98
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• 2001

A chilling-tolerant japonica-type and a chilling-susceptible indica-type of rice (Oryza sativa L.) plants were compared with respect to various physiological parameters during chilling and subsequent recovery. The japonica-type and the indica-type of rice cultivars used were Ilpumbyeo and Taebaekbyeo, respectively. The two rice cultivars exhibited little or no differences in the changes of leaf fresh weight and chlorophyll content during chilling at $5^{\circ}C$ for 3 days. During subsequent recovery at $25^{\circ}C$, however, Ilpumbyeo restored its growth more rapidly than Taebaekbyeo. Since the changes of relative water content, malondialdehyde production, an estimate of lipid peroxidation, and chlorophyll fluorescence were significantly different in the two rice cultivars during the chilling and subsequent recovery, they were found to be more sensitive physiological parameters than fresh weight and chlorophyll content. However, the differences in relation to water content, malondialdehyde production, and chlorophyll fluorescence between the two rice cultivars were smaller during chilling than those during subsequent recovery. These results suggest that relative water content, malondialdehyde production, and chlorophyll fluorescence could widely be used as important physiological parameters for screening chilling-tolerant plants.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.67-67
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• 2020

Though there is an on-going need for the diversity of ornamental plants for in-door environment, their growth and stress adaptability in comparatively low light intensity condition require further studies for implementation. Here investigates the growth and chlorophyll fluorescence parameters of Farfugium japonicum (L.) Kitam, Liriope muscari (Decne.) L.H.Bailey and Acorus gramineus Aiton under several light intensities which were based on common in-door environment. The growth measurement of the plants included the quantity, length, width and SPAD value of the leaves. Calculated values of Fm/Fo, Fv/Fm, Pi_Abs, ETo/RC and DIo/RC were used as the parameters of the chlorophyll fluorescence under 10, 50, 100 and 200 PPFD (μmol·m^-2·s^-1) light intensities. In-door plants group was put in a closed room allowing no other light sources for 10 weeks and the control group was put in glass-greenhouse for the same period. The overall in-door growth of L. muscari was not significantly different in all light intensities compared to the control group and even showed the higher SPAD values. Also, an increasing tendency of Pi_Abs value under 10 to 100 PPFD was observed implying that L.muscari could adapt well to in-door environment. Measurement of A. gramineus growth mostly showed the highest values in the control group especially in the number of the leaves. Nevertheless, chlorophyll fluorescence parameters showed no significant value difference between in-door and the control groups and thus, A. gramineus might have possibility of successful adaptation to in-door environment. F. japonicum showed deficient growth in plant height and leaf length compared to the control but, it seemed to be able to sustain ornamental value under in-door light intensities. Furthermore, Pi_Abs and DIo/RC values were increased under in-door light conditions suggesting potential adaptability of F. japonicum.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.6
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• pp.397-404
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• 1991

The steady state and decay characteristics of primary fluorescenece of phytoplanktons including Cyanophyceae and Cryptophyceae were investigated in vivo. At 580-640 nm region, fluorescence emission spectra were obtained from all algae examined. The observed fluorescence emission maxima were similiar$(\pm3\;nm)$ except Synechocorcus sp. (SYN). Considered $\lambda_{max}$ of emission spectra of phycobiliproteins and the excitation spectra with $\lambda_{max}=540-560nm$, it seems to be originated from biliproteins. Fluorescence lifetimes $(\tau)$ and decay curves were compared with standard solution of candidate organic compounds, b-phycoerythrin. The $\tau$ values obtained for phytoplankton with $\lambda_{max}=580nm$ were different depending upon the species of algae. The observed $\tau$ values were ranged from 1.39 ns to 1.95 ns. These are considerably shorter than $\tau(3.23\;us)$ for standard solution of b-phycoerythrin. The reduction of $\tau$ for phycoerythrin in vivo seems to be originated from effective energy transfer system between Chl. a and phycobiliprotein in intact cell. There are subtantial differences in fluorsecence spectra and lifetimes at the class level. At the species level, differences seems to be much smaller. The result of experiment suggests that measurement of fluorescence lifetimes may be helpful in the rapid characterization of algae. Direct application will likely be found in combination with the measurement of other luminescence parameters.

• Journal of Biosystems Engineering
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• v.37 no.4
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• pp.265-270
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• 2012

Purpose: An analytic method to design excitation and emission filters of a multispectral fluorescence imaging system is proposed and was demonstrated in an application to poultry fecal inspection Methods: A mathematical model of a multispectral imaging system is proposed and its system parameters, such as excitation and emission filters, were optimally determined by linear discriminant analysis (LDA). An alternating scheme was proposed for numerical implementation. Fluorescence characteristics of organic materials and feces of poultry carcasses are analyzed by LDA to design the optimal excitation and emission filters for poultry fecal inspection. Results: The most appropriate excitation filter was UV-A (about 360 nm) and blue light source (about 460 nm) and band-pass filter was 660-670 nm. The classification accuracy and false positive are 98.4% and 2.5%, respectively. Conclusions: The proposed method is applicable to other agricultural products which are distinguishable by their spectral properties.

• Journal of Environmental Science International
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• v.13 no.4
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• pp.359-365
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• 2004

The change of chlorophyll fluorescence parameters, O-J-I-P transients and psbA gene expression were investigated in the leaves of Crinum asiaticum var. japonicum on the natural condition in winter, in order to elucidate physiological responses of photosystem II (PS II) activity to winter stresses. The photochemical efficiencies of PS II, Fv/Fm, were significantly low in winter, contrary to its high value in summer. The values of I -qN and I-qP were lower in midday than at dawn or night both in summer and winter, although their decrease in midday was less in winter than in summer. In the O-J-I-P transients, the fluorescence intensity of J, I, P-step decreased remarkably depending on temperature drop in winter. And the D I reaction center protein of PS II decreased in late winter more than in early winter, concomitantly with relatively high content of description products of psbA gene in midday. These results indicate that low temperature in winter causes irreversible damage to PS II and subsequently leads to cell death.

• Journal of Sensor Science and Technology
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• v.13 no.2
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• pp.85-89
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• 2004

This paper represents the development of high sensitivity photo-sensor for the fluorescence detection in the integrated biological analysis system. The finger-type PIN photodiodes were fabricated as the photo-sensor, and had a high sensitivity ($I_{light}/I_{dark}$ = 8720). The interference filter consisted of $TiO_{2}$ and $SiO_{2}$ was directly deposited on the photodiodes. Deposited filter with 95.5% reflection under 532 nm and 98% transmission over 580 nm exceedingly decreased the magnitude of background signal in the detection. The PDMS micro-fluidic channels are bonded on the photodiode by $O_{2}$ plasma treatment. The detection current was proportional to two primary parameters (light intensity, concentration), and the on-chip detection system could detect fluorescence signals down to 100 nM concentration (LOD = Limit of detection of rhodamine).

• Journal of Environmental Science International
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• v.7 no.2
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• pp.133-140
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• 1998

To investigate the effects of sulfite on the chloroplast development, etiolated barley seedlings were treated with 100 mM sulfite solution every 3 hour by spraying during 96 hours greening Period. The effects were determined by chlorophyll a, b and carotenoids contents, photosynthetic electron transport activity, chlorophyll fluorescence yield and fluorescence quenching parameters. The contents of chlorophyll a and carotenoids were decreased than that of control by treatment of salfite over 48 hours greening. PS II Is more sensitive to sulfite than PS I Is. And by the addition of DPC to the chloroplasts of the barley seedling treated with sulfite, the photoreduction of DCPIP was not recovered. In greening with suite treated barley leaves, Fo, Fv and Nlh ratio were decreased with little difference from that of control. But qP, qNP and qR were lowed in comparison with those of controls whereas qE was markedly higher than that of control. Especially, It is Interesting that qR was decreased markedly compared to that of control. The results in the change of PS I activity, Nf and qP suggest that the strate of Inhibition by suite Is carbon dioxide reduction cycle.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.12a
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• pp.91-95
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• 2006

In whole world consciousness of environment maintenance have increased very quickly for the end of the 20th century. To use and disuse toxic substances have been controled at the field of industry. Also the field of lighting source belong to environmental control. And in the future the control will be strong. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem. In radiational mechanism of fluorescence lamp mercury is the worst environmental problem root. In the mercury free lighting source system the Xe gas lamp is one type. And the Ne:Xe mixing gas lamp improvements firing voltage of Xe gas lamp. Purpose and subject of this study are understand, efficiency, ideal of Ne:Xe plasma which mercury free lamp. Before ICP was designed, basic parameters of plasma, which are electron temperature and electron density, were measured and calculated by langmuir probe data. Property of electron temperature and electron density were confirmed by changing ratio of Ne:Xe.