• Korean Journal of Food Science and Technology
• /
• v.21 no.1
• /
• pp.154-163
• /
• 1989

This studies were designed to improve the productivity of L-lysine by protoplast fusion and immobilized system of fusants using strains of Brevibacterium flavum ATCC 21528, Brevibacterium lactofermentum ATCC 21086 and Corynebacterium glutamicum 820. Mutants were isolated with concentration method of $300{\mu}g/ml$ penicillin-G after treatment of $250{\mu}g/ml$ N-methyl-N-nitro-N-nitrosoguanidine. B. flavum $37-2(Hos^-,\;Kan^r,\;AEC^r)$, B. lactofermentum $6-2(Ile^-,\;Val^-,\;Str^r,\;AEC^r)$ and C. glutamicum 57-5$(Met^-,\;Thr^-,\;Rif^r,\;AEC^r)$ were isolated from mutants. Protoplasts were induced by being incubated with $500{\mu}g/ml$ lysozyme of lysis solution for 6 hr and the ratio of protoplast formation and regeneration were ranging from 97-99% and 33-37%, respectively. Fusion frequencies of fusants of BBFL 21, BCFG 37 and BCLG 59 were shown in the range from $1.25{\times}10^{-6}\;to\;5.83{\times}10^{-7}$ under the optimum conditions. The fusant BBFL 21 showed the highest productivity of $411.1\;ng/ml{\cdot}hr$ L-lysine in the lysine productivity broth at $30^{\circ}C$ for 72hr. In the immobilization systems, fusant BBFL 21 was employed in various polymer matrices such as sodium alginate, polyacrylamide, agar and ${\alpha}-carrageena$. The immobilization of sodium alginate showed the highest productivity of $413\;ng/ml{\cdot}hr$ L-lysine in the batch system. Continuous fermentation of immobilization system by using tube fermentor was produced the highest productivity $416.7\;ng/ml{\cdot}hr $ L-lysine under optimum condition.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.35 no.5
• /
• pp.455-461
• /
• 2002

limiting nutrients for phytoplankton were determined by dissored inorganic nitrogen/phosphorous (DIN/DIP) in situ and algal bioassay experiment in the Seomjin River estuary during a study period from March 1999 to October 2001. DIN/DIP ranged from 14.7 to 681.1 during the study period. DIN/DIP was over 16 at the upper and middle estuarine region where salinity was lower than 25 psu and chlorophyll a concentration was high, probably indicating P-limitation in this region while the ratio was less than 16 at the high saline (> 25 psu) region, reflecting the supply of DIP from Gwangyang Bay and thereby indicating N-limitation at the lower estuarine region. These results suggested that the spatial distribution of DIN/DIP in the study region was controlled by the high supply of phosphate from Gwangyang Bay, the low input from Seomjin River and the active uptake by phytoplankton within the estuarine system. The bioassay experiments using Skeletonema costatum, Thalaasiosira rotula and in situ phytoplankton assemblage displayed relatively higher growth of phytoplankton in the P-added culture media, indicating P-limitation. This result was well consistent with the spatial distribution of inorganic nutrients. S. costatum showed a rapid adaptation to the low salinity compared to other phytoplankton species. This phenomenon seemed to account for the strong (> $90\%$ in total cell number) S. costatum bloom in autumn in this estuary. Moreover, although phytoplankton growth rate was higher in the P-added culture media at the end of culture experiment of in situ phytoplankton, the fast growth in the trace metal-added media at the beginning of the experiment suggested a possibility of limitation by other micro-nutrients such as trace metal and vitamin etc.

• Radiation Oncology Journal
• /
• v.22 no.2
• /
• pp.138-141
• /
• 2004

Purpose : We have previously reported that human glioblastoma cells are sensitized to radiation-induced death after their exposure to trichostatin A (TSA), a histone deacetylase inhibitor (HDAC-1), prior to the irradiation. We aimed to measure the magnitude of the radiosensitizing effect of TSA in human head and neck cancer cell lines. Materials and Methods : Human head and neck cancer cell lines, HN-3 and HN-9, were exposed to 0, 50, 100, and 200 nM TSA for 18 hr prior to irradiation. Then, the TSA-treated cells were irradiated with 0, 2, 4, 6, and 8 Gy, and cell survival was measured by clonogenic assay. Results : Pre-irradiation exposure to TSA was found to radiosensitize HN-3 and HN-9 cell lines. In HN-9 cells, the fraction surviving after 2 Gy (SF2) was significantly reduced by treatment of TSA at concentration as low as 50 nM. However, a treatment with 200 nM TSA was required to significantly decrease SF2 in the HN-3 cell line. SER of pre-irradiation treatment with 200 nM TSA was 1.84 in HN-3 and 7.24 in HN-9, respectively. Conclusions : Our results clearly showed that human head and neck cancer cell lines can be sensitized to ionizing radiation by pre-irradiation inhibition of histone deacetylase (HDAC) using TSA, and that this potentiation might well be a general phenomenon.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.14 no.2
• /
• pp.135-143
• /
• 2008

An emergy concept was used to evaluate the environment and economy of the estuarine areas of Yeongsan River, Seomjin River, and Han River in Korea. The emergy evaluations clearly showed ecological and socioeconomic characteristics of the estuarine areas that act as ecological and economic centers of surrounding areas. River, tide, and rain provided most of the renewable emergy inputs to the estuarine areas with their contribution to the total emergy input less than 8%. The estuarine areas mostly relied for their operation on the purchased emergy which accounted for $92{\sim}98%$ of the total emergy input to the systems. Emergy indices such as emergy use per unit area, population carrying capacity, environmental loading ratio, and emergy sustainability index revealed that the estuarine areas of Yeongsan River, Seomjin River, and Han River are not sustainable at the current level of economic activities in the areas. The ecological economic values of the environment of the areas were in the range of $7.29{\sim}22.06$ million Em\/ha/yr. They are more than twice that for the whole country, indicating the ecological and economic importance of the eatuarine areas. It is, therefore, urgent to establish and implement estuarine management policies to protect and restore the ecological and economic potentials of the estuarine areas of Yeongsan River, Seomjin River, and Han River. Management plans for the estuarine areas should include both demand-side measures such as reduction of population and economic concentration and consideration of ecological carrying capacity in planning stages for utilization and development of the areas, and supply-side ones such as restoration of degraded ecosystems and construction of new productive ecosystems.

• Korean Journal of Environment and Ecology
• /
• v.24 no.1
• /
• pp.62-68
• /
• 2010

This study was conducted to find out how the germination, phenology and leaf morphology of Phytolacca insularis(endemic species of Korea) and P. americana(alien species) react to the global warming situation. Seed and seedlings of two species were sampled and placed under two separate conditions for the experiment. One of the seed and seedlings was treated in the glass house with control(ambient $CO_2$+ambient temperature, (AC-AT), and the other with control(elevated $CO_2$+ elevated temperature, EC-ET), over the period of one year, 2008-2009. The germination rate of two species was fast, and the time of their germination started early, when they were treated at EC-ET than at AC-AT. Furthermore, the germination rate of Phytolacca insularis(endemic species of Korea) was found to be comparatively lower than that of P. americana(alien species). The former showed only vegetative growth whereas the latter showed both vegetative growth and reproductive growth in one year period. The more $CO_2$ degree and temperature increased, phenological responses of two species, including leaf growth, the formation of flower stems, flowering, and fruit maturing, became much faster, and the time of their leaf-yellowing was delayed. The lamina length of P. insularis was not significantly affected by elevated $CO_2$ and temperature. The lamina length of P. americana, on the other hand, became longer at EC-ET than at AC-AT, but the leaf width of both species increased at EC-ET. As for the number of leaves, both species showed no difference. Finally, the ratio of the leaf area of P. insularis was high at AC-AT, but P. americana was high at EC-ET. These results indicate that P. americana, aliens species, reacts more sensitively to global warming than P. insularis, endemic species, does.

• Journal of Life Science
• /
• v.23 no.3
• /
• pp.389-398
• /
• 2013

Platycodin D is a major constituent of triterpene saponins, which is found in the root of Platycodon grandiflorum, Platycodi Radix, which is widely used in traditional Oriental medicine for the treatment of many chronic inflammatory diseases. Several pharmacological effects of this compound have been reported recently, such as anti-inflammation, immunogenicity, anti-adipogenesis, lowered cholesterol, and anti-cancer activity. However, the mechanism by which this action occurs is poorly understood. In this study, we found that platycodin D greatly increased the potential of the anti-proliferative effect in various cancer cell lines. Our data revealed that platycodin D treatment resulted in a time- and concentration-response growth inhibition of U937 cells by inducing apoptosis, as evidenced by the formation of apoptotic bodies, chromatin condensation, and the accumulation of cells in the sub-G1 phase. Apoptosis induction of U937 cells by platycodin D correlated with an increase in the Bax/Bcl-2 ratio and caused the down-regulation of IAP family members. In addition, platycodin D treatment resulted in proteolytic activation of caspase-3, the concomitant degradation of poly(ADP-ribose) polymerases, and the collapse of the mitochondria membrane potential (${\Delta}{\Psi}_m$). However, the cytotoxic effects induced by platycodin D treatment were significantly inhibited by z-DEVD-fmk, a caspase-3 inhibitor, which demonstrated the important role that caspase-3 played in the observed cytotoxic effect. These findings suggest that platycodin D may be a potential chemotherapeutic agent for use in the control of human leukemia U937 cells. These findings also provided important new insights into possible molecular mechanisms of the anti-cancer activity of platycodin D.

• Journal of Life Science
• /
• v.28 no.10
• /
• pp.1156-1162
• /
• 2018

To investigate the anti-thrombotic activities of the lotus (Nelumbo nucifera Gaertner), various hot-water extracts were prepared from the leaf, pod of seed (PS), seed, embryo of seed (ES), root, and the node of root (NR) of the lotus. The highest extraction ratio was found in the NR (20.3%), followed by the seed, root, leaf, ES, and PS. These extracts had pH and acidity levels ranging from 5.6~6.5 and 0.06~0.20%, respectively. The seed extract showed 70% brix, whereas the leaf and PS extracts showed less than 0.1% brix. The highest contents of total polyphenol (179.7 mg/g), total flavonoids (161.4 mg/g), and reducing sugar (161.4 mg/g) were observed in the leaf extract, and the highest total sugar content (873.0 mg/g) in the seed extract. Anti-coagulation assay of the extracts of NR, leaf, and PS showed strong activities. In particular, at a concentration of 5 mg/ml, the PS extract had 15-fold extended thrombin, prothrombin, and activated partial thromboplastin times. However, only the ES extract showed activities inhibitory to platelet aggregation, with treatment with 0.25 mg/ml of ES extract decreasing platelet aggregation to 25.1%, a reduction comparable to that effected by aspirin. The extracts other than the seed extract showed no hemolysis activities against human RBC at treatments of up to 1 mg/ml. These results suggest that the NR, PS, seed, and ES, all byproducts of the lotus agriculture industry, have high potential as novel sources of anti-thrombotic agent.

• Food Science of Animal Resources
• /
• v.32 no.2
• /
• pp.228-233
• /
• 2012

This study was conducted to determine the effects of stevia (Stevia rebaudiana bertoni) and charcoal supplementation on growth performance, immune response and carcass characteristics of finishing pigs. A total of 420 pigs (LYD) were randomly allocated into 7 treatments with 3 replications. Dietary treatments were 1) T1 (basal diet), 2) T2 (basal diet+0.3% stevia), 3) T3 (basal diet+0.6% stevia), 4) T4 (basal diet+0.3% charcoal), 5) T5 (basal diet+0.6% charcoal), 6) T6 (basal diet+0.3% stevia+0.3% charcoal) and 7) T7 (basal diet+0.6% stevia+0.6% charcoal). During the experimental period, average daily gain (ADG) was higher in T2 and T6 groups than the other treatments (p<0.05). Feed conversion ratio (FCR) was higher in T6 group compared to the others (p<0.05). There were no significant differences in total cholesterol level and glutamic pyruvic transaminase (GPT) activity of blood among treatments. In glutamic oxaloacetic transaminase (GOT) activity, T3, T5, T6 and T7 groups showed lower values (p<0.05) compared to T1. Insulin-like growth factor-1 concentration was higher in T2 and T6 groups than the others (p<0.05), but there were no significant differences in immunoglobulin G, lymphocyte, eosinophil, basophil and atypical lymph levels among treatments. In neutrophil, T6 showed higher level compared to the others (p<0.05). In the carcass characteristics, T6 showed higher level of a carcass grade compared to the other treatments. However, carcass length did not show any significant difference among treatments. As a result, dietary supplementation of 0.3% stevia and 0.3% charcoal showed higher ADG, higher FCR and better immune response resulting in better growth performance and carcass characteristics of finishing pigs.

• The Korean Journal of Pharmacology
• /
• v.14 no.1_2
• /
• pp.1-11
• /
• 1978

The $Na^+$-and $K^+$-induced $Ca^{++}$ release was measured isotopically by Milipore filter technique in mitochondria isolated from rabbit ventricles. The release of $Ca^{++}$ from mitochondria could be induced by 1-3 mM of $Na^+$ added in incubating medium under the presence of 0.5mM EGTA to prevent the released $Ca^{++}$ from rebinding with mitochondrial membrane. The amount of $Ca^{++}$ released was increased by increasing the concentration of $Na^+$ added. 100mM $K^+$, in itself, did not induce the $Ca^{++}$ release from cardiac mitochondria, the $Na^+$-induced $Ca^{++}$ release, however, was potentiated by the presence of $K^+$. The potentiation of $Na^+$-induced $Ca^{++}$ release by $K^+$ was proportional to the $Na^+/K^+$ ratio presented in the incubating medium. Among the monovalent cations other than $Na^+$, the release of $Ca^{++}$ from cardiac mitochondria was shared only by $Li^+$. The $Na^+$-induced $Ca^{++}$ release could be also observed in the mitochondria isolated from liver and kidney. However, the $Na^+$ sensitivity was somewhat lower in liver and kidney mitochondria than in heart mitochondria. The release of $Ca^{++}$ induced by $Na^+$ in the mitochondria isolated from the experimentally produced failured heart was not different from that in the normal heart mitochondria, and was not directly modified by $10^{-6}{\sim}10^{-5}$ M of Ouabain. From the experiments, it was suggested that the $Ca^{++}$ released from mitochondria by $Na^+$ could be used in excitation-contraction coupling process to initiate the contraction of the cardiac myofibrils. Futhermore, it appeared that the phenomenon of $Ca^{++}$ release from cardiac mitochondria by $Na^+$ and $K^+$ might be related to the inotropic effect of digitalis glycoside which could bring about the increase of $Na^+$ or the reduction of $K^+$ intracellulary through the inhibition of $Na^+$, $K^+$-ATPase.

• Microbiology and Biotechnology Letters
• /
• v.38 no.4
• /
• pp.461-466
• /
• 2010

In this study the feasibility of simultaneous electricity generation and treatment of swine farm wastewater using microbial fuel cells (MFCs) was examined. Two single-chamber MFCs containing an anode filled with different ratio of graphite felt and stainless-steel cross strip was used in all tests. The proportion of stainless-steel cross strip to graphite felt in the anode of control microbial fuel cell (CMFC) was higher than that of swine microbial fuel cell (SMFC) to reduce construction costs. SMFCs produced a stable current of 18 mA by swine wastewater with chemical oxygen demand (COD) of $3.167{\pm}80\;mg/L$ after enriched. The maximum power density and current density of SMFCs were $680\;mW/m^3$ and $3,770\;mA/m^3$, respectively. In the CMFC, power density and current density was lower than that of SMFC. CODs decreased by the SMFC and CMFC from $3.167{\pm}80$ to $865{\pm}21$ and $930{\pm}14\;mg/L$, achieving 72.7% and 70.6% COD removal, respectively. The suspended solid (SS) of both fuel cells was also reduced over 99% ($4,533{\pm}67$ to $24.0{\pm}6.0\;mg/L$). The concentration of nutritive salts, ${NH_4}^+$, ${NO_3}^-$, and ${PO_4}^{3-}$, dropped by 65.4%, 57.5%, and 73.7% by the SMFC, respectively. These results were similar with those of CMFC. These results show that the microbial fuel cells using electrode with mix stainless-steel cross strip and graphite felt can treat the swine wastewater simultaneously with an electricity generation from swine wastewater.