• Korean Journal of Plant Resources
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• v.22 no.5
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• pp.461-466
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• 2009

This study was carried out to evaluate the effects of yam (Dioscorea batatas Dence) extracts on the cell viability, growth and nucleus-DNA damage of tobacco cells which were exposed to $\gamma$-radiation stress. The viability and growth of tobacco cells exposed to 20 Gy of radiation stress were effectively recovered by pretreatment of 10 mg/L ethylacetate (EtOAc) yam extract. Pretreatment of EtOAc extract showed 20% higher cell viability and fresh weight growth than that of cells without pretreatment in 20 Gy radiation treated tobacco cells. Nucleus-DNA damage was measured as the ratio of tail length (T) to head length (H) in individual comet image isolated from tobacco cells. The T/H ratio of control-cells and treated-cells at 20 Gy were 1.05 and 1.68, and % head DNA of those cell were 86.7 and 71.3%, respectively, suggesting that nuclei of tobacco cells were severely damaged in the integrity of DNA by the treatment of $\gamma$-radiation. However, pretreatment of MeOH, EtOAc and n-BuOH extracts decreased radiation induced DNA-damage in the tobacco cells, showing T/H ratio of 1.37, 1.01 and 1.10 and % head DNA of 81.5, 87.6 and 88.7%, respectively.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.115-121
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• 2006

The purpose of this study was to investigate applicability of pretreatment on the existing biological treatment for domestic wastewater reclamation. From Jar Tests, it was found that optimum dosage of coagulant was PAC 0.5mg/L and $FeCl_3$ 180mg/L for urban sewage. In this study, PAC 0.5mg/L was selected considering sludge production and the amount of coagulant required. In a continuous experiment performed with combining chemical coagulation and biological treatment, a considerable removal efficency was obtained in term of BOD, SS, T-N, T-P and ABS. When the raw sewage was supplied into the pre-chamical treatment facility, the removal of BOD and SS was 48.3% and 81.1%. However T-N removal was very low which means T-N consists of $NH_3-N$ mostly. T-P was almost completely recluced by the chemical addition. The effluent BOD & SS was 57~76 and 21~43mg/L, which could reduce the size of biological treatment facility. From the cost estimation pre-chemical treatment could save around half of the area required for biological treatment with post ceagulation.

• Biotechnology and Bioprocess Engineering:BBE
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• v.5 no.5
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• pp.372-378
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• 2000

The cell culture of Angelica gigas Nakai producing decursin derivatives and immunostimulating polysaccharides was preserved in liquid nitrogen after pre-freezing in a deep freezer at -70$^{\circ}C$ for 480 min. The effects of the cryoprotectant and pretreatment before cooling were investigated to obtain the optimal procedure for cyropreservation. When compared to mannitol, sorbitol, or NaCl with a similar osmotic pressure, 0.7 M sucrose was found to be the best osmoticum for the cryopreservation of A. gigas cells. In the pre-culture medium, the cells in the exponential growth phase showed phase showed the best post-freezing survival after cryopreservation. A mixture of sucrose, glycerol, and DMSO was found to be an effective cryoprotectant and a higher concentration of the cryoprotectant provided better cell viability. When compared with the vitrification, the optimum cryopreservation method proposed in this study would seem to be more effective for the long-term storage of suspension cells. The highest relative cell viability established with the procedure was 89%.

• KSBB Journal
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• v.31 no.1
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• pp.85-89
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• 2016

Lactic acid fermentations were conducted using water hyacinth. It is known that the pretreatment and enzyme hydrolysis process optimize the potential of water hyacinth. Lactic acid produced by using lactic acid bacteria. All cells were grown at $37^{\circ}C$ and initial pH 5.5. Lactic acid production was measured by HPLC. All Lactobacillus strains could produce lactic acid from pretreated water hyacinth. The highest lactic acid was achieved when lactic acid fermentation was carried out by L. delbrueckii for D-form and L. helveticus for L-form lactic acid production. The lactic acid concentration was 10.70 g/L by L. delbrueckii and it converted glucose in the medium to lactic acid, almost perfectly. Lactic acid production became higher when fermentation was carried out at a controlled pH 5.5. Lactic acid yield and productivity were 0.52 g/g and 0.19 g/L/h for L. helveticus, while L. delbrueckii was 0.64 g/g and 0.27 g/L/h. This study showed that water hyacinth medium could be alternative medium which can replace the complex and expensive medium for growing Lactobacillus strains in production of lactic acid.

• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.570-575
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• 2015

The green algae have cellulose as a main structural component of their cell wall and the cellulose content in green algae is much higher than other marine algae such as brown algae and red algae. Furthermore, green algae do not contain lignin in their cell wall and store starch as food in their plastids. Thus, it was investigated that the effect of hydrothermal pretreatment process utilizing microwave irradiation for Ulva pertusa Kjellman, a division of green algae, which is expected to be utilized for bioenergy production, on the enzymatic hydrolysis. The hydrothermal temperature have an effect on the pretreatment of Ulva pertusa Kjellman, but the effect of power of microwave irradiation is negligible. The rate of enzymatic hydrolysis was increased as the hydrothermal temperature increased until $140^{\circ}C$. The enzymatic hydrolysis of pretreated Ulva pertusa Kjellman under the optimum pretreatment conditions (50 W of microwave irradiation power and $150^{\circ}C$ of hydrothermal temperature) with cellulase, ${\alpha}$-amylase, and Novozyme 188 having ${\beta}$-glucosidase acitivity resulted in the saccharification of 96 wt% of total carbohydrate in Ulva pertusa Kjellman during 3 hrs, while it took 24 hrs for the enzymatic hydrolysis of untreated Ulva pertusa Kjellman. It confirmed that the hydrothermal pretreatment was effective on Ulva pertusa Kjellman for the enzymatic hydrolysis.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.1
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• pp.90-96
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• 2008

In order to meet the stringent requirement of sludge disposal and to find ecological alternative, aerobic digestion coupled with alkaline pretreatment was studied. The treated sludge was tested for the potential of liquid fertilizer. In the aerobic digestion, it was obvious that the performance of digester B(fed with the sludge pretreated by NaOH) was better than that of digester A(fed with raw sludge) in terms of COD and SS removal. SS and VSS removal rates in digester B were 66% and 69%, respectively. At 5 days, TSS removal rate reached 47% in the digester B, which was 71% of final TSS removal rate. It revealed that the pretreatment process can shorten the retention time of aerobic digestion. 94.1% of TCOD in the raw sludge was reduced by alkaline pretreatment and aerobic digestion. Final SCOD was in the range of 220$\sim$230 mg/L implying the sludge was stabilized. Nitrification and pH drop were observed in the aerobic digestion. Final nitrate concentrations in digester A and B were 445.4 and 223.1 mg/L and final pH in digester B was 3.0. Biological assays reported that leaf size of cucumber seedling increased with nitrate concentration and sludge to soil ratio. The sludge treated by alkaline and aerobic digestion promoted the growth of seedling leaf and stem remarkably compared to raw sludge. In contrast, the aerobically digested sludge without pretreatment improved leaf growth and inhibited stem growth.

• Journal of Plant Biology
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• v.17 no.1
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• pp.9-14
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• 1974

Inhibitory effect of alantolactone and isoalantolactone was shwon in Avena straight growth test and in the formation of adventitious root in Phaseolus seedling. However, di-, and tetrahydroalantolactones given no effect on the elongation and the rooting. Inhibitory effect of alantolactone could partly be removed by cysteine, cystine, and reduced glutthione. The plant materials were made less sensitive to alantolactone by the pretreatment of cysteine, but cysteine supplied after the treatment of alantolactone brought about no effect on the action of alantolactone. A new spot was shown on TLC plate from the mixture of alantolactone and cysteine, indicating that alantolactone can be inactivated by cysteine, not cystine, without any biological processes.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.68-68
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• 2018

In this study, we investigated whether S. baicalensis rhizome ethanol extract (SBRE) has antioxidant capacities against oxidative stress induced cellular damage in the HaCaT keratinocytes. Our results revealed that treatment with SBRE prior to hydrogen peroxide ($H_2O_2$) exposure significantly increased the HaCaT cell viability. SBRE also effectively attenuated $H_2O_2$ induced comet tail formation, and inhibited the $H_2O_2$ induced phosphorylation levels of the histone ${\gamma}H2AX$, as well as the number of apoptotic bodies and Annexin V positive cells. In addition, SBRE exhibited scavenging activity against intracellular ROS generation and restored the mitochondria membrane potential loss induced by $H_2O_2$. Moreover, $H_2O_2$ enhanced the cleavage of caspase-3 and degradation of poly (ADP-ribose)-polymerase as well as DNA fragmentation; however, these events were almost totally reversed by pretreatment with SBRE. Furthermore, SBRE increased the levels of HO-1 associated with the induction of Nrf2. Therefore, we believed that SBRE may potentially serve as an agent for the treatment and prevention of neurodegenerative diseases caused by oxidative stress.

• Korean Journal of Biological Psychiatry
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• v.1 no.1
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• pp.17-30
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• 1994

Several different classes of antidepressants(ADs) with newer drugs becoming available have been used for the phamacological management of a broad spectrum of mental disorders, among which depressive disorder is most commonly indicated. Successful clinical use of ADs requires a complete understanding of the psychopharmacological properties of ADs and on accurate knowledge of patients, characteristics based on clinical experience and theoretical framework. This paper aims at providing some practical information on the clinical use of ADs to assist clinicians in treating patients with major depression. The author describes (1) different classes of ADs and their presumed mechanisms of action, (2) clinical characteristics of ADs focusing on side-effect profiles, (3) some issues arising during the treatment course such as : a) pretreatment tasks, b) choice of ADs, c) therapeutic drug dose and monitoring of drug concentration, d) three stages of treatment and e) strategies in refractory depression and (4) ADs in special patient groups.

• Mycobiology
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• v.50 no.6
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• pp.457-466
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• 2022

Epicoccum nigrum is a saprophytic or endophytic fungus that is found worldwide. Because of the antagonist effects of E. nigrum on many plant pathogens, current studies on E. nigrum have focused on the development of biological control agents and the utilization of its various metabolites. In this study, E. nigrum was collected from a wheat field, and its genetic diversity was analyzed. Phylogenetic analyses identified 63 isolates of E. nigrum divided into seven groups, indicating a wide genetic diversity. Isolates antagonized the wheat pathogen Fusarium graminearum, and reduced disease symptoms caused by F. graminearum in wheat coleoptiles. Moreover, pretreatment of wheat coleoptiles with E. nigrum induced the upregulation of pathogen-related (PR) genes, PR1, PR2, PR3, PR5, PR9, and PR10 in wheat coleoptiles responding to F. graminearum invasion. Overall, this study indicates that E. nigrum isolates can be used as biological pathogen inhibitors applied in wheat fields.