• Journal of Environmental Science International
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• v.24 no.10
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• pp.1253-1264
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• 2015

This study assessed the fertilizing value of struvite deposit recovered from swine wastewater in cultivating Chinese cabbage. Struvite deposit was compared with commercial fertilizers: complex, organic and compost to evaluate the fertilizing effect of struvite deposit. Laboratory pot test obviously presented that the struvite deposit more facilitated the growth of Chinese cabbage than organic and compost fertilizers even though complex fertilizer was the most effective in growing Chinese cabbage. It was revealed that the growth rate of Chinese cabbage was simultaneously controlled by phosphorus (P) and potassium (K). Also, the nutrients such as nitrogen (N), P, K, calcium (Ca) and magnesium (Mg) were abundantly observed in the vegetable tissue of struvite pot. Specifically, P was the most abundant component in the vegetable tissue of struvite pot. Meanwhile, the utilization of struvite as a fertilizer led to the lower accumulation of chromium ($Cr^{6+}$) than other pots, except for compost fertilizer pots, and no detection of cadmium (Cd), arsenic (As) and nickel (Ni) in the Chinese cabbage. The experimental results proved that the optimum struvite dosage for the cultivation of Chinese cabbage was 2.0 g struvite/kg soil. On the basis of these findings, it was concluded that the struvite deposits recovered from swine wastewater were effective as a multi-nutrient fertilizer for Chinese cabbage cultivation.

• Proceedings of the KSAR Conference
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• 2000.10a
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• pp.3-4
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• 2000

The synthesis of acyl-CoA catalyzed by acyl-CoA synthetase (ACS, EC 6.2.1.3) from fatty acid, ATP, and CoA is a crucial reaction in mammalian fatty acid metabolism. In arachidonate metabolism, acyl-CoA synthetase(ACS) plays a key role in the esterification of free arachidonate into membrane phospholipids. Following its release by the action of calcium dependent phospholipase, free arachidonate is believed to be rapidly converted to arachidonoyl-CoA and reesterified into phospholipids in order to prevent excessive synthesis of eicosanoids. In previous studies, we have characterized five ACSs (designated as ACS1-5) with different tissue distribution. ACS1, ACS2, and ACS5 are similar in structure and fatty acid preference, and completely different from ACS3 and ACS4. The latter are arachidonate-preferring enzymes closely related in structure but expressed in different tissues: ACS3 mRNA is highly expressed in the brain and the mRNA for ACS4 is expressed in steroidogenic tissues including adrenal gland, ovary, and testis. To learn more about the potential function of ACS4 in arachidonate metabolism, we have produced knock-out mice for ACS4 gene. ACS4+/- females become pregnant less frequently and produce small litters with extremely low transmission of the disrupted alleles. Striking morphological changes including extremely enlarged uterine filled with numerous proliferative cysts of various size were detected in ACS4+/- females. Furthermore, marked accumulation of prostaglandins were seen in the uterus of heterozygous females. These results indicate that ACS4 is critical for the uterine arachidonate metabolism and heterozygous disruption of its gene lead to impaired pregnancy.

• The Korean Journal of Ecology
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• v.28 no.3
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• pp.121-127
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• 2005

To reveal vegetation history and environmental changes in Mt. Jiri, sediment cores were collected from Wangdeungjae moor of Mt. Jiri. Overall dry matter accumulation rates and sedimentation rates by $^{14}C-dating$ were 0.027 $kg{\cdot}m^{-2}{\cdot}yr^{-1}$ and 0.184 mm/yr since 1250 ($760{\pm}40$ yrs BP, 14 cm in depth). There are three pollen zones; the first zone is below 14 cm depth where Quercus dominated, the second zone is from 14 cm to 6 cm depth where Gramineae increased and Quercus and Salix dominated and the third zone is from 6 cm depth to the top where Pinus and Quercus dominated. Total pollen concentration gradually increased from bottom to the top of sediment core, which implies wet, anaerobic and cool condition during covered period by the core. Calcium and magnesium contents had increased since 14 cm depth, with peaks at 13 and 20 cm depths. This indicates that groundwater had recently become relatively more important than surface water as water source of Wangdeungjae moor Exotic plant or Chenopodiacea pollen was less than 1%. There was little variation in total N and P contents along the length of the core. These results support that Wangdeungjae moor has been little affected by anthropogenic activities. Also, nutrients and heavy metal contents indicate the baseline condition of Wangdeungjae moor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.4
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• pp.503-513
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• 2007

The obese population has been increasing worldwide and obesity has become one of the socioeconomic problems. Obesity raises more concerns as more studies regarding its direct and indirect relativity to several diseases such as type II diabetes, hypertension, etc. are published. Since leptin, an important signal in the chronic control of food intake and energy expenditure, was discovered in 1994, there has been a great accumulation of knowledge on fighting obesity by facilitating pharmacological and nutritional strategies on the molecular level of the body weight control system. In particular, evidences are accumulating that particular food components affect our physiological function and gene expressions which are associated with body weight control. In this study, we review the four mechanisms for weight control and antiobesity functional agents such as HCA, L-carnitine, CLA, chitosan, calcium supplements capsaicin contained in red pepper, and oriental herbal mixture. We also describe about the efficacy and working mechanism of these functional agents on the basis of antiobesity mechanisms.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.298-302
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• 2019

Acidic soil significantly reduces crop productivity mainly due to aluminum (Al) toxicity. Alfalfa (Medicago sativa L.) roots were exposed to aluminum stress (Al₃⁺) in calcium chloride (CaCl₂) solution (pH4.5) and root growth, physiological and antioxidant enzyme responses were investigated. The root growth (length) was significantly inhibited after 48 h of aluminum stress imposition. Histochemical staining with hematoxylin indicated significant accumulation of aluminum in Al stress-treated root tissues. Histochemical assay were also performed to detect superoxide anion, hydrogen peroxide and lipid peroxidation, which were found to be more in root tissues treated with higher aluminum concentrations. The enzymatic activity of CAT, POD and GR in root tissues was slightly increased after Al stress treatment. The result suggests that Al stress alters root growth in alfalfa and induces reactive oxygen species (ROS) production, and demonstrates that antioxidant enzymes involved in detoxification of Al-mediated oxidative stress.

• Journal of Life Science
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• v.11 no.5
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• pp.415-422
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• 2001

Many secreted proteins have disulfide bonds that are important for their structure and function. Protein disulfide isomerase (PDI, EC 5.3.1.4.), an enzyme that catalyzes the formation and rearrangement of thiol/disulfide exchange reactions, is a resident of the endoplasmic reticulum (ER). The subcellular localization and its function as catalyst of disulfide bond formation in the biosynthesis of secretory and cell membrane proteins suggest that PDI plays a key role in the secretory pathway. We have isolated a cDNA encoding protein disulfide isomerase from Bombyx mori(bPDI). It has been characterized under ER stress conditions (dominantly induced by calcium ionophore A23187, tunicamycin and DTT), which is known to cause an accumulation of unfolded proteins in the ER. Furthermore, It has also been examined for tissue distribution(pronounced at the fat body), hormonal regulation (juvenile hormone, insulin and juvenile +transferrin; however, it is not effected by transferrin alone), and the effect of exogenous bacteria (peak at 16 h after infection) on the bPDI mRNA expression. The results suggest that bPDI is a member of the ER stress protein group, and it may play an important role in exogenous bacterial infection in fat body, and that homones regulate its expression.

• Korean Journal of Materials Research
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• v.28 no.7
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• pp.376-380
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• 2018

Microalgae produce not only lipids for biodiesel production but also valuable biochemicals which are often accumulated under cellular stress mediated by certain chemicals. While the microcarriers for the application of drug delivery systems for animal cells are widely studied, their applications into microalgal research or biorefinery are rarely investigated. Here we develope dual-functional magnetic microcapsules which work not only as flocculants for microalgal harvesting but also potentially as microcarriers for the controlled release of target chemicals stimulating microalgae to enhance the accumulation of valuable chemicals. Magnetic microcapsules are synthesized by layer-by-layer(LbL) coating of PSS-PDDA on $Fe_3O_4$ nanoparticle-embedded $CaCO_3$ microparticles followed by removing $CaCO_3$ sacrificial templates. The positively charged magnetic microcapsules flocculate microalgae by electrostatic interaction which are sequentially collected by the magnetophoretic separation. The microcapsules with a polycationic outer layer provide efficient binding sites for negatively charged microalgae and by that means are further utilized as a chemical-delivery and flocculation system for microalgal research and biorefineries.

• Environmental Engineering Research
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• v.21 no.1
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• pp.29-35
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• 2016

This study evaluated the fertilizing value of struvite deposit recovered from swine wastewater in cultivating lettuce. Struvite deposit was compared to complex fertilizer, organic fertilizer and compost to evaluate the fertilizing effect of struvite deposit. Laboratory pot test showed that the struvite deposit better enhanced lettuce growth in comparison to commercial fertilizers. It was revealed that the growth rate of lettuce was simultaneously controlled by phosphorus (P) and magnesium (Mg). Moreover, nutrients such as nitrogen (N), P, K, calcium (Ca) and magnesium (Mg) were abundantly observed in the vegetable tissue of struvite pot. Meanwhile, struvite application led to the lower accumulation of mercury (Hg), lead (Pb), chromium ($Cr^{6+}$) and nickel (Ni). In addition, no detection of cadmium (Cd), arsenic (As) and nickel (Ni) in the lettuce tissue was observed in struvite application pots. The experimental results proved that the optimum struvite dosage for lettuce cultivation was 0.5 g struvite/kg soil. The column experiments clearly showed that ammonia nitrogen was more slowly released from struvite deposit than from complex fertilizer. Consequently, it was concluded that the struvite deposits recovered from swine wastewater were effective as a multi-nutrient fertilizer for lettuce cultivation.

• Journal of Microbiology and Biotechnology
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• v.16 no.4
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• pp.531-537
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• 2006

Lactic acid-producing bacteria (LABs) are known to have various beneficial properties for health. However, they are generally considered to have an adverse effect on teeth, since they produce acid. Nonetheless, milk and cheese containing specific LAB strains were recently found to have an inhibitory effect on dental caries in children, with an inhibitory activity towards the growth of Streptococcus mutans suggested as the responsible mechanism. Accordingly, the current study selected a probiotic candidate for oral health and studied its inhibitory mechanism against dental caries. Twenty-two LAB species belonging to eleven genuses were screened for promoting bone nodule formation using direct microscopic examination. Only one isolate, Weissella kimchii strain PL9001, increased the bone nodule formation significantly. The addition of W. kimchii strain PL9001 to bone cells prepared from mouse calvaria increased the bone nodule formation, calcium accumulation, and activity of alkaline phosphatase (the osteoblastic marker). Moreover, W. kimchii strain PL9001 inhibited the invasion of Streptococcus mutans into bone cells, and an organic extract of the culture supernatant of W. kimchii strain PL9001 inhibited the growth of Strep. mutans. Therefore, the results suggest that W. kimchii strain PL9001 can be used as a preventive measure against dental caries. This is the first time that a LAB has been shown to promote bone nodule formation and prevent the invasion of Strep. mutans into bone cells.

• Korean Journal of Pharmacognosy
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• v.45 no.3
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• pp.214-219
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• 2014

Artemisia apiacea is a traditional herbal medicine using treatment of eczema and jaundice in Eastern Asia including China, Korea, and Japan. In this study, the three phytosterol constituents were isolated and identified from the hexane fraction of 80% aqueous methanol extract of A. apiacea. Compounds were isolated using open column chromatography (silica gel). Their chemical structures were also established using $^1H$-NMR and $^{13}C$-NMR. Moreover, neuroprotective activity of each compound against glutamate-induced neurotoxicity in hippocampal HT-22 cell line was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Furthermore, Inhibition of reactive oxygen species (ROS) and calcium ion ($Ca^{2+}$) accumulation were measured for elucidation of neuroprotective mechanism of isolated compounds. They showed that stigmasterol had neuroprotective activity against the glutamate-induced toxicity by inhibition of ROS and $Ca^{2+}$ production. In conclusion, isolated compound of A. apiacea might be useful for therapeutic agent against neurodegenerative diseases.