• Korean Journal of Fisheries and Aquatic Sciences
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• v.23 no.2
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• pp.155-166
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• 1990

There have been many problems like plasmolysis in the ultrastructural studies with kelps. The present study was conducted with series of different fixatives and buffer solutions and several resins to solve the plasmolysis phenomena. The fixative of 1470 mosmol($3\%$ glutaraldehyde, $2.4\%$ paraformaldehyde in 0.05M cacodylate buffer with 0.2M sucrose and $0.5\%$ caffeine at pH of 7.2) showed the least frequency of plasmolysis. The relationship between the concentration of primary fixatives and the frequency of plasmolysis was not found. With above fixative the possibility of plasmolysis during infiltration period was not identified using ultra-low viscosity resin. Generally, the kelp(Laminaria religiosa) contains a lot of mucilage, which interupts the infiltration of fixative. The possible physiological mechanisms related with mucilage secretion may be unable to fix the region of plasmalemma properly.

• Transactions of the Korean hydrogen and new energy society
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• v.8 no.4
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• pp.155-160
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• 1997

Generation of hydrogen and oxygen gas from water is mostly accomplished by electrolysis. In this report, a scheme is presented regarding the gas generation based on plasmolysis. Unlike electrolysis water dissociation by electrical discharge (plasmolysis) requires a high voltage to cause either electron emission or electron capture, and subsequent ionization of involved molecular species. When electrical discharge is initiated between electrodes separated by water-vapor interface, a very large electric field(~100kV/cm) is developed at the tip of the electrode placed in the vapor phase. It is found that the efficiency of plasmolysis depends on the polarity of the electrode placed in the vapor phase. Also presented is the scheme of hydrogen and oxygen generation by such electrical discharge.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.28 no.1
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• pp.128-132
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• 1983

The water relations parameters such as original osmotic pressure $(\Pi_0)$, osmotic pressure $(\Pi_p)$, at the incipient plasmolysis, the volume of osmotic water $(V_o)$ at the full turgor, the relative water content $(RWC^*)$ at the incipient plasmolysis, the volume of osmotic water$(V_p)$ at the incipient plasmolysis, the volume of symplasmic and apoplastic water$(w_s)$ at the maximum turgor, $V_pV_o, \; V_oW_s, \; W_sD_w, \; V_oF_w$ and the elastic modulus were measured through the pressure chamber (DIK-PC-40 Model) technique with the Williams and Geumgangdaerip soybean cultivar shoots. The original osmotic pressure$(\P $i_{0}$ )$, of the both cultivars shoots were appeared insignificant differences as 8.1 bar and 7.8 bar respectively. The osmotic pressure($\pi$$_{p}$ ) at the incipient plasmolysis was 9.0 bar in Williams and 10.4 bar in Geumgangdaerip. The relative water content(RW $C^{*}$) at the incipient plasmolysis was 86.0 per cent in Geumgangdaerip and 92.6 per cent in Williams. The ratio of volume of osmotic water( $V_{p}$ ) at the incipient plasmolysis to total symplasmic water$(V_o)$ , i.e., $V_p/V_o$ was 83.4 per cent in Geumgangdaerip and 90.4 per cent in Williams. The elastic modulus of Geumgangdaerip shoots showed higher value than Williams$(8.5 $\times$ 10^2bar)$ as $1.6 \times10^5$ bar.r.

• Horticultural Science & Technology
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• v.30 no.1
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• pp.79-84
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• 2012

An efficient protocol for cryopreservation of madder hairy root cultures has been developed using droplet-vitrification. In previous study, combining loading solution C4 (35% PVS3) and vitrification solution B5 (80% PVS3) was the most effective method. In this study, we tried three types of vitrification solution, B5, A3 (90% PVS2, on ice), and A5 (70% PVS2, on ice). Combining loading solution C4 and vitrification solution A5 (on ice) showed the best regeneration rate in this study. Histological changes of the cells within the hairy root of madder were also observed in different steps. The cells from the hairy roots of the control treatment were full and intact with different size of vacuoles and obvious cell nucleus having a dark nucleolus. After the stage of preparing for cryopreservation (after preculturing, loading, followed by dehydration solution A5 or B5), intercellular spaces had become distinct, and within cells, the cytoplasms had become denser and week plasmolyses had appeared. The cell plasmolyses were much more apparent and we measured the degree of plasmolysis by calculating, the area of cell/the area of cytoplasm. The value of plasmolysis degree was the highest in the combination of preculture, loading solution C4, and dehydration solution A5, 1.97. Because the highest regeneration rates appeared in the treatment of A5 for 20 min, we could assume that the optimal degree of plasmolysis for cryopreservation might be around 1.97. The changes in cell structure during cryopreservation might be a useful basis for the development of a proper long-term preservation method for madder germplasms.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.267-275
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• 2020

Anthocyanins are antioxidant compounds susceptible to environmental factors. Anthocyanin encapsulation into yeast cells is a viable solution to overcome this problem. In this study, the optimal factors for anthocyanin encapsulation were investigated, including anthocyanin concentration, plasmolysis contraction agent, and ethanol concentration, and response surface methodology was evaluated, for the first time. Anthocyanin from Hibiscus sabdariffa L. flowers was encapsulated into Saccharomyces cerevisiae using plasmolysis contraction agent (B: 3%-20% w/v), ethanol concentration (C: 3%-20% v/v), and anthocyanin concentration (A: 0.15-0.45 g/ml). The encapsulation yield and anthocyanin loss rate were determined using a spectrometer (520 nm), and color stability evaluation of the capsules was performed at 80℃ for 30 min. The results of the study showed that these factors have a significant impact on the encapsulation of anthocyanin, in which ethanol agents have the highest encapsulation yield compared to other factors in the study. Statistical analysis shows that the independent variables (A, B, C), their squares (A², B², C²), and the interaction between B and C have a significant effect on the encapsulation yield. The optimized factors were anthocyanin, 0.25 g/ml; NaCl, 9.5% (w/v); and ethanol, 11% (v/v) with an encapsulation yield of 36.56% ± 0.55% and anthocyanin loss rate of 15.15% ± 0.98%; This is consistent with the expected encapsulation yield of 35.46% and loss rate of 13.2%.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.55-58
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• 1999

Plant water status during growth is directly and indirectly associated with seed yield. The objective of the present study was to determine the genotypic differences in leaf water characteristics at an early growth stage of soybean [Glycine max (L.) Merrill] plants through the pressure-bomb technique. Measurements of water potential as well as relative water content (RWC) were made at the third leaf from the fully-expanded top leaf of eight different soybean genotypes grown for 31 to 35 days after field emergence. On the basis of the modified exponential model, pressure-volume (PV) curves were fitted well ($R^2$=0.92＊＊ to 0.99＊＊ for the curvi-linear region and R=0.67＊＊ to 0.96＊＊ for the linear region), indicating that a segmented model using PROC NLIN of SAS could be used effectively to estimate the leaf water characteristics. The regression analysis for the pressure-volume (PV) curve revealed genotypic variation in the solute potential at saturation (Ψ$_{s,sat}$ :-10.7 to -14.8 bar), solute potential at incipient plasmolysis (Ψ$_{s,ip}$ : -14.3 to -18.3 bar), RWC at incipient plasmolysis (RW $C_{ip}$ : 83.3 to 91.7%), high integrated turgor pressure from saturation to plasmolysis ( $_1$$^{b}$ : 0.39 to 0.81), and maximum volumetric modulus of elasticity ($\varepsilon$$_{max}$ : 150 to 445 bar).).

• Journal of Environmental Science International
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• v.9 no.4
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• pp.331-337
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• 2000

The variation of microorganisms (activated slude, Saccharomyces cerevisiae, Aureobasidium pullulans) caused by the biosorption of $Pb^{2+}$ was observed by TEM and microscope. By the TEM observation of S. cerevisiae, the plasmolysis and lysis of cell wall or cell membrane were occurred by the penetration of $Pb^{2+}$ into the inner cellular region. However, in the case of A. pullulans, the plasmolysis and lysis of cell wall or cell membrane were not occurred because of the prevention of $Pb^{2+}$ penetration by the extracelluar polymeric substances (EPS). A flocculation of microorganisms, in the case of A. pullulans, was observed by the $Pb^{2+}$ accumulation after 3~4 h and the color was changed from white to black after 1 day. The flocculation of activated sludge was improved by the accumulation $Pb^{2+}$ after 1 h, however, the floc was broken up and the settling efficiency decreased after 1 day.

• Journal of Forest and Environmental Science
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• v.22 no.1
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• pp.71-75
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• 2006

Water relations of Kalopanax pictus leaves obtained from the P-V curve. In the upper leaves of Kalopanax pictus seedlings, the original osmotic pressure at maximum turgor was -1.44 MPa, and the osmotic pressure at incipient plasmolysis point was -1.84 MPa, and the relative water content at incipient plasmolysis point was 78.2%.

• The Korean Journal of Ecology
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• v.15 no.1
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• pp.47-58
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• 1992

This study is to investigate the change of the seasonal patterns of relative water relations parameters by the pressure-volume curves in pinus koraiensis needles. The osmotic potentials at full water saturated(Ψ0, sat) and at incipient plasmolysis(Ψ0, tlp) increased in growing season, while decreased in non-growing season. The maximum bulk modulus of elasticity(Emax), relative water content(RWCTLP), and relativefree water content(FWCtlp) at incipient plasmolysis in non-growing season were higher than these of growing season. The maximum pressure potential(Ψp, max) varied from 1.16 to 2.18MPa, torgor index(TI) varied from 3.1 to 4.7. The osmole number(Ns/dw) and symplastic water (Vo/DW) were variable seasonally. The maximum water content(Vt/DW) and apoplastic water(AW) were relatively high in early growing stage, and then decreased to needle aging. The pressure potential(Ψp) and water potential(Ψ) in winter needles were rapidly decreased with decreasing of relative water content. The matric potential occupied over 10 percent of water potential with less than-2.0 MPa.

• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.462-467
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• 1997

The DIS process(dewatering and impregnation soaking process) are using for dewatering of food materials at room temperature. And the DIS process are resulted in diffusion process as well as dewatering phenomena. During the DIS process, plasmolysis or cytorrhysis was happened by according to solute size. A tissue state of food material was very important variables for movement of water or solute, and running conditions are important for dewatering and impregnation. And models for DIS process were fundamentally given by Fick's law at unsteady state or mass balance. For example, Bicompartmental Model was given for quantification of water loss and solid gain.