• KSBB Journal
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• v.9 no.5
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• pp.443-449
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• 1994

Fermentation characteristics of Kluyveromyces fragilis CBS 1555 with Jerusalem artichoke juice, in extractive ethanol fermentation in aqueous two phase systems composed of polyethylene glycol 20000 (PEG) and crude dextran(Dx), were investigated as a function of initial sugar concentrations, concentrations of ethanol formed, or fermentation time. Both specific ethanol production rate increased with decrease in concentrations of PEG and Dx in two-phase systems. Without being related to the compositions of aqueous two-phase system, maximum specific cell growth rate and maximum specific ethanol production rate were showed in the initial sugar concentration fo $80g/\ell$ and $120g/\ell$, respectively. The inhibition effects of ethanol on specific cell growth rate and specific ethanol production rate decreased with decrease in PEG concentration and in the range of 2.5 to 5% Dx. Specific cell growth rate and specific ethanol production rate was fitted as an exponential function and a hyperbolic function, respectively, of the concentrations of ethanol formed. Overall ethanol productivity increased with increase in initial sugar concentrations, and also the required time for the maximum productivity was so. Ethanol production rate by the elapsed fermentation time showed the maximum value in the initial sugar concentration of $160g/\ell$.

• KSBB Journal
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• v.9 no.3
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• pp.279-286
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• 1994

A mathematical model has been derived and used to describe phosphoprotein partitioning in Fe(III) IDA-PEG/dextran two-phase systems. This model includes the inhibitory effects of hydrogen and hydroxyl ion concentrations on protein partitioning. For aqueous two-phase partitioning experiments, the Al and A2 subcomponents of ovalbumin carrying two and one surface phosphoryl group(s) were purified using an immobilized metal ion affinity chromatography (IMAC). The ratio of partition coefficients in the presence and absence of Fe(III)IDA-PEG, K/Ko, increased in the pH range of 3.0 to 5.0 due to deprotonation of the second oxygen of the phosphoryl group, and above pH 5.0 declined steeply by the inhibitory binding of hydroxyl ions to the metal ion. This partitioning behavior was well described by the mathematical model. The binding constants for formation of the complex between the phosphoryl group and the Fe(III)IDA-PEG were found to be $6.1{\times}10^3M^{-1} and 2.3{\times}10^4M^{-1}$ in the top and bottom phases, respectively. These values are 3-5 times those for interaction of Cu(II)IDA-PEG with a single surface-accessible histidine.

• KSBB Journal
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• v.22 no.2
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• pp.84-90
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• 2007

Trehalose is non-reducing disaccharide which is found in bacteria, fungi, plants and insects. Trehalose has been determined by several analysis methods. To monitor the concentrations of trehalose in a process, enzymatic methods have more advantage over others, e.g. more specific. In this work, trehalase was immobilized on VA-epoxy polymer and applied to FIA systems. The behaviours of these FIA systems were characterized and used to monitor the trehalose concentrations. Use of optical detection technique was chosen for trehalose-FIA system. On-line monitoring data and off-line data were measured by HPLC.

• Journal of Animal Science and Technology
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• v.57 no.8
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• pp.27.1-27.6
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• 2015

This study was designed to investigate the effects of ${\alpha}$-tocopherol and granulosa cells monolayer on nuclear maturation and cleavage rates of ovine cumulus-oocyte complexes (COCs). The COCs (n = 2814) were matured in maturation medium supplemented with various concentration of ${\alpha}$-tocopherol (0, 5, 10, $15{\mu}g/ml$), oocytes were incubated at $39^{\circ}C$ with 5 % $CO_2$ for 24 h in three culture systems: (a) maturation medium (MM; n = 884), (b) co-cultured with granulosa cells (CG; n = 982) and (c) co-cultured with granulosa cells and cells were further cultured in MM for 12 h (CG + 12hMM; n = 948). Our results showed that ${\alpha}$-tocopherol had no effect on GVBD and MII as compared to control group, but when ${\alpha}$-tocopherol added to maturation medium the rate of cleavage decreased. This indicates interaction of above mentioned factors in any of the treatments showed no significant differences on the rate of maturation and cleavage stages (MII, GVBD and cleavage) (p > 0.05). The oocytes co-cultured with granulosa cells for 24 h had beneficial effects on cleavage rate. The maximum MII and cleavage rates were achieved when oocytes had extra 12 h culture in the maturation medium without granulosa cells. Results also showed our modified co-culture system (CG + 12hMM), improved rates of MII and the cleavage in comparison with other studied maturation systems.

• Journal of Pharmacopuncture
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• v.22 no.2
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• pp.83-89
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• 2019

Introduction: Oxidative stress (OS) during uncontrolled hyperglycemia has a pivotal role in pancreatic dysfunction. Our study aimed to demonstrate that crocin can potentiate anti-oxidant defense systems of pancreatic cells to improve oxidative stress. Methods: Male Wistar rats were divided randomly into four groups: a normal group, a normal-treated group, a diabetic group and a diabetic-treated group (n = 6 rats per group). Diabetes was induced by a single dose of streptozotocin (45 mg/kg/IV). The treated groups received crocin daily for 8 weeks (40 mg/kg/IP). At the end of the experiment, rats were sacrificed and pancreas tissue was obtained. Subsequently, the concentrations of malondialdehyde (MDA), nitrate and glutathione as well as the enzymatic activities of catalase and superoxide dismutase (SOD) were determined in all animals. Data were analyzed by two-way ANOVA with appropriate post hoc testing and a probability value of P < 0.05 was considered to represent a statistically significant difference in mean values. Results: Uncontrolled hyperglycemia weakened the anti-oxidant system by decreasing SOD and catalase enzyme activity in pancreatic tissues and induced OS by increasing the MDA content in diabetic non-treated animals. Crocin potentiated the anti-oxidant defense system by increasing the activity of both SOD and catalase, and improved OS by diminishing MDA production in pancreatic cells of rats contained in the diabetic-treated group. Conclusion: Based on our results, it is concluded that uncontrolled hyperglycemia can weaken the anti-oxidant defense system and cause the development of OS. Also, crocin can improve OS in pancreatic cells by potentiating the anti-oxidant defense system.

• Journal of Life Science
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• v.22 no.4
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• pp.499-507
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• 2012

Previous work has characterized myomodulin A (MMA, PMSMLRLamide) and myomodulin E (MME, GLQMLRLamide) purified from the central nervous systems of the sea hare, $Aplysia$ $Kurodai$, using the anterior byssus retractor muscle (ABRM) of the mussel, $Mytilus$ $edulis$. The amino acid sequences of MMA and MME were the same as those of the myomodulin family peptide found in other mollusks. In this study, we synthesized MME, its derivatives, and other neuropeptides to investigate the relationship between the structure and biological activity of MME. The primary structures of MME's derivatives, Des[$Gly^1$]-MME, Des[$Gly^1,Leu^2$]-MME, and Des[$Gly^1,Leu^2,Gln^3$]-MME, were LQMLRLamide, QMLRLamide, and MLRLamide, respectively. MMA and synthetic peptides were tested on ABRM in $M.$ $edulis$ as well as muscle preparations in $Achatina$ $fulica$. MME displayed an inhibitory effect on phasic contraction of the ABRM at $1{\times}10^{-9}$ M or higher. MME also had a relaxing effect on the catch-tension of AMRM at $1{\times}10^{-8}$ M. Both MMA and its analogs stimulated a contractile response on the crop and relaxed the catch-relaxing response on the penial retractor muscle of $A.$ $fulica$. These results suggest that MME and its analogs have modulatory effects on various muscles of mollusks. This study has also laid the groundwork for future neural and circuit modulation studies during animal behavioral changes.

• Journal of Plant Biotechnology
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• v.44 no.4
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• pp.484-489
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• 2017

Lilies as cut flowers are one of the most popular ornamental plants in South Korea. It is necessary to develop lily cultivars with high qualities. Therefore, highly efficient propagation systems are needed following release of elite cultivars. In this study, we used taurine treatment to improve the growth conditions including shoot and bulb formation, fresh weight gain, and reduction of rooting and browning. We experimentally evaluated the effect of taurine as a growth stimulator, at concentrations of 0, 2.5, 5, 10, 15 and 20 mg/l. The results showed that 20 mg of taurine enhanced shoot formation by 85% and increased fresh weight 5.5-fold, which was higher than the approximately four-fold increase in the control. In addition, multiple bulb formation rate was increased by 80% and rooting by 82% following exposure to 20 mg/l of taurine. The efficiency of taurine treatment was higher than that of control with 50% multiple bulb formation rate and 60% rooting rate. The browning was 10.6% at 2.5 mg/l of taurine when compared with 0.8% at 20 mg/l. Taurine showed a positive effect on the overall growth of lily plants in terms of increased fresh weight, shoot formation rate, rooting, and formation of multiple bulbs, indicating that taurine can be used as an alternative to amino acids or as an antioxidant such as citrate and vitamin C in plant tissue culture.

• Journal of Plant Biotechnology
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• v.33 no.3
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• pp.171-184
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• 2006

According to ISAAA report, the global area of genetically modified (GM) crops increased more than 50 fold during the ten-year period from 1996 to 2005 with a sustained double-digit growth rate of 10%. This biotechnology adoption is one of the highest rates of technology adoption in agriculture history and this phenomenon indicates that the industrial value of the GM crops is highly perspective. In addition, the year 2010, 60% of cereal seeds in the global market would be GM or biotechnology related seeds so that the GM crop regards as the second green revolution that could provide a huge impact to food and agriculture. Nevertheless, there has not been any GM variety ever successfully commercialized in Korea and even none of the GM crops has ever been approved for safety testing by risk assessment. This seems that Korean agriculture industry might be indeed lost in the war of future seed market. However, lots of evidence show that Korean scientists have established advanced technologies and protocols to develop GM crops for last 20 years. Actually there have been many cases of successful transformation of crops that were previously known very difficult in transforming. Therefore, Korean agbiotechnology arena firmly holds an infrastructure for developing GM crops with a superior technology. Then what were the problems? Why has even a single GM crop not been commercialized in Korea? The tardiness shown by business in adopting the GM crop is caused by many factors: academical weakness, poor research funding, short knowledge of risk assessment, public concern, no successful experience, lack of professional leaders on GM variety development, lack of systems toward industrialization and inappropriate target transgenes from the beginning. In order to catch up in the race for the new green industry, each one of us in private sectors alongside academia and national research institutes needs to focus altogether on what can be done best in terms of choosing crops, investing fund and establishing a road map for commercialization of GM crops.

• Animal cells and systems
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• v.1 no.3
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• pp.467-473
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• 1997

Taurine (2-aminoethanesulfonic acid), one of bioactive amino acid in the mammalian brain, is known to exert inhibitory effects on neurons via GABA receptor. In the present study, we examined effects of taurine on glutamateinduced neurotoxicity on hippocampal neuron cell culture using cell counting method and lactate dehydrogenase (LDH) assay. After 10 d of culture, cells were stimulated with appropriate drugs. Only 43% of cultured neuronal cells survived at one day after stimulation with 500 uM L-glutamate for 10 min. Survival rate was enhanced by 82% in the presence of 10 mM taurine. LDH activity from the culture supernatant incubated with a combination of L-glutamate and taurine was less than half of that with L-glutamate alone. In the next series of experiments, interleukin-6 (IL-6) mRNA expression in cultured astrocytes was investigated using reverse tanscription-PCR (RT-PCR). IL-6 mRNA was detected in the astrocytes stimulated with L-glutamate in a dose-dependent manner, while not detected in the unstimulated control astrocytes. The expression of IL-6 mRNA caused by 10 mM glutamate was inhibited by taurine, but not by GABA. These findings demonstrated a neuroprotective action of taurine against glutamate-induced toxicity.

• Animal cells and systems
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• v.2 no.1
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• pp.133-137
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• 1998

The present study aims to characterize a cDNA encoding zebrafish thyroid hormone receptor $\alpha{1}$ $(zTR\alpha{1)}$ in order to investigate its possible role in the early stage of embryonic development. A mobility shift assay showed that $zTR\alpha{1}$ overexpressed in COS7 cells specifically bound to thyroid hormone response element (TRE). In addition, the specific interaction of anti-rat $TR\alpha{1}$ antibodies with $zTR\alpha1$/TRE complexes demonstrated that the cDNA clone encoded zebrafish thyroid hormone receptor $\alpha{1}$. Transient cotransfection assays showed that $zTR\alpha{1}$ repressed the transcription which was induced by retinoic acid (RA), a well-characterized embryonic morphogen. These results suggest that zTRal may be involved in regulating the RA-induced gene transcription during early embryonic development.