• Journal of the Society of Naval Architects of Korea
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• v.60 no.4
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• pp.213-221
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• 2023

The demand for Liquefied Natural Gas (LNG) carriers and LNG-fueled ships has significantly increased in recent years due to the sulfur-oxide emission regulations by the International Maritime Organization (IMO). The main goal of this paper is to introduce the process for the Engineering Critical Assessment (ECA) of IMO independent type-B cargo tanks made from 9% nickel alloy. A methodology proposed by the British Standard was used to conduct ECA for any structure with initial flaws. Based on this standard, a Matlab code was developed to perform ECA. Coarse mesh Finite Element Analysis (FEA) was performed on an independent type-B LNG cargo tank with a capacity of 15,000 m³. The location with the highest development of maximum principal stress was identified at the bottom of the cargo tank. Fine mesh FEA was performed to obtain the stress range required for ECA. The dynamic cargo tank loads used for FEA were determined using some ship rules presented by Det Norske Veritas. As a result of performing a 20-year long-term crack propagation analysis with a semi-elliptical surface crack, the fracture-to-yield ratio exceeded the Fracture Assessment Line (FAL) and some structural reinforcement was necessary. Performing a 15-day short-term crack propagation analysis, the fracture-to-yield ratio remained within the FAL, and no significant LNG leaks were expected. This paper is believed to provide a guide for performing ECA of LNG cargo tanks in the future by providing the basic theory and application sample necessary to perform ECA.

• Biomolecules & Therapeutics
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• v.32 no.4
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• pp.467-473
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• 2024

In this study, we investigated the potential protective effects of (+)-afzelechin (AZC), a natural compound that is derived from Bergenia ligulata, on lipopolysaccharide (LPS)-induced inflammatory responses. AZC is known to have antioxidant, anticancer, antimicrobial, and cardiovascular protective properties. However, knowledge regarding the therapeutic potential of AZC against LPS-induced inflammatory responses is limited. Thus, we investigated the protective attributes of AZC against inflammatory damage caused by LPS exposure. We examined the effects of AZC on heme oxygenase (HO)-1, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) in LPS-activated human umbilical vein endothelial cells (HUVECs). In addition, the effects of AZC on the expression of iNOS, tumor necrosis factor (TNF)-α, and interleukin (IL)-1β were analyzed in the lung tissues of LPS-injected mice. Data revealed that AZC promoted the production of HO-1, inhibited the interaction between luciferase and nuclear factor (NF)-κB, and reduced the levels of COX-2/PGE2 and iNOS/NO, thereby leading to a decrease in the signal transducer and activator of transcription (STAT)-1 phosphorylation. Moreover, AZC facilitated the nuclear translocation of Nrf2, increased the binding activity between Nrf2 and the antioxidant response elements (AREs), and lowered the expression of IL-1β in the LPS-treated HUVECs. In the animal model, AZC significantly reduced the expression of iNOS in the lung tissue structure and the TNF-α level in the bronchoalveolar lavage fluid. These findings demonstrate that AZC possesses anti-inflammatory properties that regulate iNOS through the inhibition of both NF-κB expression and p-STAT-1. Consequently, AZC has potential as a future candidate for the development of new clinical substances for the treatment of pathological inflammation.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1373-1380
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• 2023

This study investigated the effects of coumarin, a flavonoid known for various physiological activities like antiviral, anticancer, and antibacterial properties, on anti-oxidants and anti-inflammatory processes, aiming to explore its application in functional cosmetics. The results are as follows: Cell toxicity experiments using RAW 264.7 cells showed no significant cytotoxicity for coumarin at any concentration, indicating its safety for skin application. Observing coumarin's antioxidant activity through DPPH radical scavenging showed concentration-dependent effectiveness, though not significantly varied with concentration. The inhibition of silica-induced ROS production in cells was concentration-dependent. Both NO production inhibition and histamine release measurements showed concentration-dependent suppression. These findings suggest that Coumarin can be effectively used as a natural ingredient in cosmetic development for its antioxidant and anti-inflammatory properties.

• Journal of Korean Society of Water and Wastewater
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• v.37 no.6
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• pp.375-382
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• 2023

The binary oxide adsorbent using Fe and Mn (Fe-Mn) has been prepared by precipitation method to enhance the removal of phosphate. Different amounts of chitosan, a natural organic polymer, were used during preparation of Fe-Mn as a stabilizer to protect an aggregation of Fe-Mn particles. The optimal amount of chitosan has been determined considering the separation of the Fe-Mn particles by gravity from solution and highest removal efficiency of phosphate (Fe-Mn10). The application of Fe-Mn10 increased removal efficiency at least 15% compared to bare Fe-Mn. According to the Langmuir isotherm model, the maximum uptake (q_m) and affinity coefficient (b) were calculated to be 184 and 240 mg/g, and 4.28 and 7.30 L/mg for Fe-Mn and Fe-Mn10, respectively, indicating 30% and 70% increase. The effect of pH showed that the removal efficiency of phosphate was decrease with increase of pH regardless of type of adsorbent. The enhanced removal efficiency for Fe-Mn10 was maintained in entire range of pH. In the kinetics, both adsorbents obtained 70% removal efficiency within 5 min and 90% removal efficiency was achieved at 1 h. Pseudo second order (PSO) kinetic model showed higher correlation of determination (R²), suggesting chemisorption was the primary phosphate adsorption for both Fe-Mn and Fe-Mn10.

• Food Science and Preservation
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• v.31 no.3
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• pp.462-473
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• 2024

The anti-inflammatory effect of beluga lentil extract (BLE) and its underlying mechanisms were investigated in lipopolysaccharide (LPS)-treated RAW 264.7 cells. Treatment with BLE significantly decreased nitric oxide (NO) production and protein and mRNA expressions of inducible NO synthase (iNOS) in LPS-treated RAW 264.7 cells. Down-regulation of this inflammatory gene expression was not associated with NF-κB/MAPK signaling pathways, and further mechanistic studies demonstrated that BLE decreased LPS-induced iNOS expression through upregulation of the nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated heme oxygenase-1 (HO-1) expression. These results suggest that beluga lentil represent a potential source of natural anti-inflammatory agents, and further studies will be necessary to determine its anti-inflammatory effects in vivo.

• BMB Reports
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• v.28 no.4
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• pp.293-300
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• 1995

The radical centers detected in the reaction of metmyoglobin (MetMb) with hydrogen peroxide ($H_2O_2$) have been studied by using a spin trapping technique. A broad 5-line asymmetric electron spin resonance (ESR) spectrum, with $2A_{max}=4.07\;mT$ and $2A_{min}=2.97\;mT$, obtained after incubation of MetMb with $H_2O_2$ in the presence of a spin trap, 5,5-dimethyl pyrroline-N-oxide (DMPO) was gradually weakened with time and disappeared completely by 6 min after addition of guanidine-HCl (14 M). When a higher concentration (6 M) of the agent was added, the signal disappeared within 40 see and the DMPO/OH signal appeared immediately. Then, a new 8-line signal with similar intensities grew gradually and was fixed by 45 min, coexisting with the DMPO/OH signal. This new signal was found to be composite, consisting of two different radical species. One of the 6-line signals, with $a_N$ 1.49 mT and $a_H$ 0.988 mT, was assigned to the DMPO/phenoxyl radical adduct. The second 6-line signal with $a_N$ 1.55 mT and $a_H$ 2.22 mT was assigned to carbon-centered radical adduct. When 3,3,5,5-tetramethylpyrrolin-N-oxide (TMPO), was employed in the place of DMPO, another broad asymmetric 5-line signal was detected with $2A_{max}=3.99\;mT$ and $2A_{min}=3.04\;mT$, which is virtually identical to that obtained from the DMPO system The shape of the spectrum of the TMPO adduct changed drastically, with lapse of time resulting in a broad singlet after 40 min. The broad singlet was assigned to the porphyrin radical adduct. Incubation of globin with Fenton reagent in the presence of DMPO initially gave a DMPO/OH signal. Then, a new 12-line signal began to grow after one minute and fixed after 15 min. coexisting with the DMPO/OH signal, This 12-line signal was assigned to DMPO/phenoxyl with $a_N$ 1.47 mT, $a_{{\beta}H}$ 0.99 mT and $a_{{\gamma}H}$ 0.13 mT. A minor concentration of carbon-centered radical adduct was also detected. This radical composition is identical to that of guanidine HCl treated MetMb/DMPO/$H_2O_2$ system, indicating that the radical producing conditions are somehow common in both systems. Heme iron can be released by excess $H_2O_2$ in the MetMb/$H_2O_2$ system, providing for Fenton reagent. When MetMb was pretreated with tyrosine blocking agent, $KI_3$ the broad 5.line MetMb-derived signal was not detected in the MetMb/DMPO/$H_2O_2$ system, whereas no such effect was detected on such system of Hb in which the radical center was assigned to cysteine residue not tyrosine, indicating that tyrosine residue is a main radical center produced in the MetMb/$H_2O_2$ system Thus, the present data strongly support the previous indication that the apomyoglobin-derived radical center formed in the reaction of MetMb with $H_2O_2$ is a tyrosine residue.

• Journal of Life Science
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• v.21 no.4
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• pp.561-567
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• 2011

This study was performed to evaluate the anti-inflammatory and antioxidant activities of methanol extract from natural products. Cell viability was determined by MTT assay. The production of NO and TNF-${\alpha}$ were measured by Griess assay and enzyme-linked immunosorbent assay (ELISA). In order to effectively screen for anti-inflammatory agents, we first examined the inhibitory effects of 24 natural products on the production of lipopolysaccharide (LPS)-induced nitric oxide (NO) in RAW 264.7 cells. Three extracts of Terminalia chebula Retz., Lavandula spica L., and Dalbergia odorifera T. significantly inhibited NO production. The three extracts significantly decreased production of NO in a dose-dependent manner. Terminalia chebula Retz. decreased TNF-${\alpha}$ production. Antioxidative effects of the three extracts were measured based on polyphenol and flavonoid contents and DPPH radical scavenging activity assay. The three extracts showed high polyphenol contents as well as strong DPPH scavenging activities. In particular, Terminalia chebula Retz. contained the highest polyphenol and flavonoid levels of 616 and $96\;{\mu}g/mg$, respectively, compared to Lavandula spica L. and Dalbergia odorifera T. As DPPH radical scavensing activities, RC50 values of Terminalia chebula Retz. were $2.09\;{\mu}g/ml$.

• Journal of Korean Society of Environmental Engineers
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• v.39 no.11
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• pp.634-640
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• 2017

Toxicity and fate assessment is necessary in the evaluation of the environmental, health and safety risks of engineered nanomaaterials (ENMs). Therefore, in order to ensure the reproducibility, reliability and relevance of ENMs toxicity results, stable and monomodal dispersion protocols in toxicity test media are needed. Zinc oxide nanoparticles (nZnO) are widely used in various products such as cosmetic products, paper, paints etc. In this study, nZnO dispersions in ecotoxicity test media were produced by following a series of steps of modified National Institute of Standards and Technology (NIST) Special publication 1200-5. In addition, natural organic matter (humic acid (HA)) was used as a stabilizing agent to disperse nZnO in the test media. The hydrodynamic diameters (HDD) of the nZnO in dispersion ranged between 150 and 200 nm according to the dynamic light scattering (DLS) measurement. Based on these dispersions in ecotoxicity test using ecological species (Oryzias latipes, Daphnia magna, Pseudokirchneriella subcapitata and Chironomusus riparius), dispersion protocol was found to have a considerable potential in ecotoxicity test of ENMs.

• Journal of Life Science
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• v.27 no.9
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• pp.994-1002
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• 2017

This study was performed to evaluate the anti-oxidative, anti-inflammatory, anti-allergy, and whitening effects of Zizania latifolia ethanol extracts prepared from 5 different ethanol concentrations (10, 30, 50, 70, and 90%). As the ethanol concentration in the extraction solvent was increased, the radical scavenging activities also increased. The inhibitory activity of Z. latifolia ethanol extracts on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells tended to increase as the content of ethanol increased. The highest inhibitory activity was obtained with 70% ethanol extract. The antiallergy effects of Z. latifolia ethanol extracts were tested by measuring the release of ${\beta}-hexosaminidase$ in IgE-sensitized RBL-2H3 cells. The suppressive effect of Z. latifolia ethanol extracts increased in a dose-dependent manner as the proportion of ethanol increased, except for the 10% ethanol extract. Furthermore, the inhibitory effects of Z. latifolia ethanol extracts against melanin production in ${\alpha}-melanocyte$ stimulated hormone (MSH)-stimulated B16F0 cells increased as the ethanol ratio increased, and 70 and 90% ethanol extracts showed similar inhibitory activities to arbutin, a positive control, at $250{\mu}m$. The present study confirmed the efficacy of Z. latifolia ethanol extracts in various areas, demonstrating antioxidative, anti-inflammation, antiallergy, skin protective, and skin whitening effects, with no cytotoxicity. It could be used as a raw material in functional foods, as well as in cosmetics.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.416-423
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• 2023

Figs has known to have antioxidant, whitening, anti-inflammatory, and antibacterial effects in their leaves, roots, stems, latex, and fruits. In order to develop cosmetic materials based on natural products, we have studied on the skin activity of the ficin in latex as well as the whitening function of the fruit extract with 70% ethanol, and used it as a raw material for released cosmetic product. However, there is little research on the demand for the development of new eutectic solvent extraction methods and its ability to control skin inflammation and psoriasis regulation. Thus, in this study, we evaluated the effectiveness of fig fruit extracts and fractions using eutectic solvent extraction for skin inflammation control and psoriasis. First, fig fruits were extracted under optimal eutectic solvent conditions and fractionated with n-hexane, dichloromethane, ethyl acetate, and butanol. First, the antioxidant activity and inhibition of nitric oxide (NO) production were confirmed in mouse macrophage RAW264.7 cells. In addition, as a result of observing the mRNA expression through RT-PCR, pro-inflammatory cytokines such as TNF-α, IL1α, and IL-1β were suppressed significantly in the hexane, dichloromethane, and ethyl acetate fractions. In addition, it was confirmed in TNF-α stimulated HaCaT keratinocyte model. Finally, chemokine CC motif ligand 20 (CCL20), marker gene of human psoriasis skin disease, was significantly suppressed in the hexane, dichloromethane, and ethyl acetate fractions. These results suggested its anti-inflammatory and skin soothing effect and the possibility of development as an excellent skin soothing natural cosmetic material in the future through future clinical trials.