• Korean Journal of Food Science and Technology
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• v.44 no.3
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• pp.350-355
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• 2012

This study investigated the physiological effects of three species of Auricularia known as Auricularia polytricha (JNM21001), Auricularia auricula-judae black (JNM21002), and Auricularia auricula-judae brown (JNM21012). In the ORAC assay, Auricularia spp. showed antioxidant activities in the order of JNM21001>JNM21012>JNM21002. All Auricularia spp. strongly inhibited the action of ${\alpha}$-amyloglucosidase up to 60%. In order to further test in vivo anti-obesity effects, high fat diet induced ICR obese mice fed a diet containing 20% fat were used. All Auricularia spp. supplementation during high fat diet feeding significantly reduced body weight gain, epididymal fat pads weight, and lowered the food efficiency ratio compared to the high fat control (HFC) group. In particular, the group fed with JNM21012 had a lower average daily body weight gain of 0.45 g/day, demonstrating similar levels to the normal diet fed group. The group fed with JNM21012 significantly reduced lowered serum triglycerides (42%), total cholesterol (81%), and LDL-cholesterol level (66%) compared with the HFC group.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.563-574
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• 2007

Laser induced breakdown spectroscopy (LIBS) is a recently developed analytical technique that is based upon the measurement of emission lines generated by atomic species close to the surface of the sample, thus allowing their chemical detection, identification and quantification. With powerful advantages of LIBS compared to the conventional analytical methodology, this technique can be applied in the detection of heavy metals in the field. LIBS allows the rapid analysis by avoiding laborious chemical steps. LES have already been applied for the determination of element concentration in a wide range of materials in the solid, liquid and gaseous phase with simplicity of the instrument and diversity of the analytical application. These feasibility of rapid multi elemental analysis are appealing proprieties for the in-situ analytical technique in geochemical investigation, exploration and environmental analysis. There remain still some limitations to be solved for LIBS to be applied in soil environment as an in-situ analytical technology. We would like to provide the basic principle related to the plasma formation and laser-induced breakdown of sample materials. In addition, the matrix effect, laser properties and the various factors affecting on the analytical signal of LIBS was dealt with to enhance understanding of LIBS through literature review. Ultimately, it was investigated the feasibility of LIBS application in soil environment monitoring by considering the basic idea to enhance the data quality of LIBS including the calibration method for the various effects on the analytical signal of LIBS.

• Journal of Food Hygiene and Safety
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• v.33 no.5
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• pp.399-403
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• 2018

In this study, safety investigations on harmful microorganisms and mycotoxins were conducted on honeybee drone pupae as a new food material, which is rich in nutrients and capable of being mass produced in apiaries. The honeybee drone pupae produced in apiaries were collected from three different regions in Korea and frozen immediately. Subsequently, the samples were subjected to freeze-drying. According to the Korean Food Code test method, coliforms, Salmonella species, Staphylococcus aureus, and enterohemorrhagic Escherichia coli were not detected in 280 honeybee drone pupas. In addition, mycotoxins, aflatoxin $B_1$, ochratoxin A, deoxynivalenol, and zearalenone were not detected. Therefore, it is proposed that the honeybee drone pupae collected from the beehives and immediately frozen as safe from harmful microorganisms and mycotoxins and can be used as a food material.

• Clean Technology
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• v.5 no.1
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• pp.49-61
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• 1999

Fenton's oxidation can improve the biodegradability of refractory organic wastewater by generating $OH{\cdot}$ which is one of the most reactive species. Fenton's reagent is used to treat a variety of industrial waste containing a range of toxic organic compounds. But this process cannot be economical because of high chemical cost of $H_2O_2$, ferrous ion solution and high sludge disposal cost. In this study, we proposed a modified Fenton's oxidation process which can reduce the reagent cost and obtain better removal efficiencies with less Fenton's reagents, and have a good potential of sludge recycling. In modified Fenton reaction, ferrous ion solution is adjusted to optimal pH with NaOH. Then it added to the sample and reacted to $H_2O_2$. For the experiment, synthetic wastewater made of phenol, which is one of the typical water pollutants, was used and the ionic strength of this wastewater was controlled by adding $NaHCO_3$. The effects of DO, ionic strength, and $H_2O_2$ dosing methods were investigated. As a result, modified Fenton's treatment efficiencies are better than conventional Fenton's reaction treating leachate and dyeing wastewater. And modified Fenton's treatment efficiencies combined to the sludge recycling for a half of Iron dosage are as good as the conventional Fenton's for a normal Iron dosage.

• Journal of Microbiology and Biotechnology
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• v.30 no.11
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• pp.1720-1728
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• 2020

We have previously characterized AprESJ4, the major fibrinolytic enzyme from Bacillus subtilis SJ4 (Yao et al., 2019). During that study, we observed a 68 kDa protein with fibrinolytic activity. In this study, we cloned the gene (vprSJ4) encoding the 68 kDa protein, a mature Vpr and minor protease secreted by Bacillus species. vprSJ4 encodes a preproenzyme consisting of 810 amino acids (aa) including signal sequence (28 aa) and prosequence (132 aa). The mature enzyme (650 aa) has a predicted molecular weight of 68,467.35. Unlike Vprs from other B. subtilis strains, VprSJ4 has 4 additional amino acids (DEFA) at the C-terminus. vprSJ4 was overexpressed in Escherichia coli. PreproVprSJ4 was localized in inclusion bodies, and subjected to in vitro renaturation and purification by an affinity column. SDS-PAGE and western blot showed that autoprocessing of preproVprSJ4 occurred and 68 kDa and smaller proteins were produced. The optimum pH and temperature of the recombinant VprSJ4 were pH 7.0 and 40℃, respectively. Kinetic parameters of recombinant VprSJ4 were measured by using an artificial substrate, N-succinyl-ala-ala-pro-phe-p-nitroanilide. Coexpression of vprSJ4 and aprESJ4 using pHY300PLK increased the fibrinolytic activity a further 117% when compared with aprESJ4 single expression using the same vector in B. subtilis WB600.

• Journal of the Korean Chemical Society
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• v.44 no.6
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• pp.526-532
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• 2000

Cation exchange separation and inductively coupled plasma atomic emission spectrometric(ICP-AES) determination of ruthenium in HCl solutions were studied to quantitatively determine ruthenium in spent nuclear fuels. Ruthenium-bearing samples were dissolved with the mixed acid solution(9 : 1 mole ratio, HCl-HNO$_3$) using an acid digestion bomb. Based on the absorption spectra and ion exchange behaviour of ruthenium in hydrochloric acid media, its possible chemical species were discussed. On a cation exchange column (0.7 ${\times}$ 8.0 cm) packed with AG 50W ${\times}$ 8(100~200 mesh) and equilibrated with 0.5 M HCl, ruthenium was eluated with 0.5 M HCl while uranium was retained on the column. The established separation method was applied to a simulated spent nuclear fuel and resulted in the recovery of 98.5% with a relative standard deviation of 0.7%.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.8
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• pp.1107-1113
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• 2018

Ultrasonography and photodynamic therapy have been proposed as useful tools as a treatment for inducing necrosis of cells using reactive oxygen species. Apoptosis is an internal mechanism necessary for cells regardless of damage. Ultrasound has the effect of inducing the apoptosis of these cells, and the frequency of 1 MHz is the most applicable area for medical use. The laser which is generally used in photodynamic therapy has a heat reaction and the treatment is limited. However, as a small light emitting diode is developed, it shows possibility to minimize the equipment and reduce heat reaction. On the other hand, there are relatively few researches on direct effects of light compared with studies using photosensitizers, and the area is also limited. Therefore, in this paper, we have developed a cancer cell proliferation control module using ultrasonic and light emitting diodes, which have relatively few side effects, and quantitatively analyze the effect of the module to propose an optimal suppression technique.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.403-412
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• 2017

To investigate the control effect of insect pests by natural enemies, sticky traps were used in commercial tomato greenhouses in Chun-cheon and the experiment fields of Gangwon-do Agricultural Research and Extension Services, Republic of Korea using semi-forcing culture (February to June). We selected low toxicity pesticides, environment-friendly agricultural materials (EFAM), and natural enemies of the study species, combinations of which have been previously used in farms to control insect pests. In this study, Trialeurodes vaporariorum and thrips, which are major agricultural insect pests, were studied in experimental greenhouses. The adult T. vaporariorum population was observed in mid-April and the population of thrips showed occurrences in early April. Regarding seasonal fluctuation, T. vaporariorum peaked in mid-May and thrips peaked after June. one insecticide, spiromesifen suspension concentrate (SC); one fungicide, cyazofamid SC; and two EFAMs containing neem tree extract were shown to be slightly toxic to Encarsia formosa and Orius laevigatus. The results of this study could be used to develop management models using natural enemies of control the insect pests; T. vaporariorum and thrips in semi-forcing culture of tomato.

• Journal of Advanced Marine Engineering and Technology
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• v.39 no.4
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• pp.495-500
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• 2015

Currently the fish aquaculture industry of Korea is focused on the mass culture of flatfish (Paralichthys olivaceus) and and rockfish (Sebastes schlegeli) with completely controlled culture techniques. Recently, there has been considerable interest in new species development, such as the starry flounder (Platichthys stellatus). The value of starry flounder (Platichthys stellatus) as a raw fish increases with time because it is tasty, light, and bouncy. In this paper, the growth characteristics dependent on the LED wavelengths and the optimal growth conditions of the starry flounder were studied. In these experiments 4 different kinds of LED lighting, configurations were designed and prepared using red, green, blue and white, respectively. The fish aquaculture experiments were conducted over 10 weeks in four fish tanks, each installed with a different color of LED lighting. 10 starry flounders of 13 ~ 17g were placed into each tank. The effects of each color of light on the growth rate of the starry flounders were then examined. As a result, the starry flounders under the green LED lighting showed the highest growth rate, followed by the white, red, and blue LED lighting. Based on these results, a green light provides a suitable breeding environment for the starry flounder.

• The Korea Journal of Herbology
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• v.35 no.4
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• pp.25-36
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• 2020

Objective : Reflux esophagitis is a disease caused by the reflux of gastric acid and inflammation due to unstable gastroesophageal sphincter. The aim of the present study was to clarify the effect of Phellodendri Cortex (PC) on chronic reflux esophagitis (CRE) in rats. Methods : The anti-oxidant activity of PC was measured by total polyphenol, total flavonoid contents, 1, 1-diphenyl-2-picrylhydrazyl (DPPH), and 2, 2'-azinobis-3-ethyl-enzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity. A CRE was established surgically in SD rats. And then CRE rats were treated with water or PC 200 mg/kg body weight for 14 days. Besides, the anti-oxidant and inflammatory protein levels were evaluated using western blotting. Results : PC reduced esophagus tissues injury. The total polyphenol (36.05 ± 0.25 mg/g) and total flavonoid (72.90 ± 0.61 mg/g) of PC showed a high content. PC strongly reduced radical scavenging activities (DPPH IC₅₀ 43.58 ± 1.54 ㎍/㎖; ABTS IC₅₀ 36.75 ± 0.35 ㎍/㎖). Moreover, reactive oxygen species (ROS) and peroxynitrite (ONOO^-) levels in serum, the protein expression of inducible nitric oxide synthases (iNOS) were significantly reduced. In addition, the protein expression of NADPH oxidases related to oxidative stress were significantly reduced in PC compared to CRE control. PC effectively reduced inflammatory factors including, TNF-α, and IL-6 via NF-κBp65 inactivation through the inhibition of p-IκBα and increased anti-oxidant enzyme such as HO-1, SOD, catalase, and GPx-1/2 via Nrf2 activation. Conclusions : Taken together, these results show that PC can alleviate the esophageal mucosal ulcer though the inhibition of NF-κB inflammatory and the enhancement of Nrf2 anti-oxidant pathway.