• Korean Journal of Clinical Laboratory Science
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• v.53 no.4
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• pp.363-370
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• 2021

This study was conducted to evaluate the dermal cytotoxicity of lead acetate (LA) and other heavy metal compounds, and the protective effect of Lespedeza bicolor (LB) extract on LA-induced cytotoxicity in cultured B16-/F10 melanoma cells. The study evaluated the antioxidative effects of LB due to its electron-donating ability (EDA), inhibitory effects on melanization and improving cell viability. LA significantly decreased cell viability in a dose-dependent manner, and the XTT₅₀ value was determined at 52.7 µM in the studied cultures. Based on the Borenfreund and Puerner's toxicity criteria, LA was estimated to be highly cytotoxic. LA-induced cytotoxicity and cell damage was reversed by the antioxidant activity of kaempferol (KAE), thereby remarkably improving cell viability. A study of the protective effects of the LB extract on LA-induced cytotoxicity showed that the LB extract remarkably increased cell viability in the LA-treated group, and also inhibited the EDA and the total amount of melanin. The above results suggest oxidative stress-mediated cytotoxicity of LA. In the study, LB extract effectively prevented LA-induced cytotoxicity via its antioxidative activity and inhibition of melanization. In conclusion, natural resources like LB extracts may be useful agents for the prevention of oxidative stress-mediated cytotoxicity and melanization by heavy metallic compounds such as LA.

• Korean Journal of Environmental Biology
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• v.39 no.3
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• pp.311-318
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• 2021

In this experiment, we investigated the toxicity of tebuconazole (fungicide) using domestic frog embryos, along the FETAX (Frog Embryo Teratogenesis Assay-Xenopus) protocol. Bufo gargarizans, Hyla japonica, and Pelophylax nigromaculatus embryos were incubated, and investigation of the tebuconazole effect was performed by the probit analysis. As a result, depending on the concentrations of tebuconazole, the mortality and malformation rates were increased and larval body length was decreased. The teratogenic concentrations (EC₅₀) of tebuconazole were 34.4mg L^-1, 10.6mg L^-1, and 14.9mg L^-1, respectively, and the embryo lethal concentrations(LC₅₀) of tebuconazole were 74.7 mg L^-1, 38.5 mg L^-1, and 39.1 mg L^-1, respectively. The teratogenic index (TI) valuesof tebuconazole were 2.19, 3.58, and 2.65; thus, it showed teratogenicity in embryonic development of these three frogs. These results revealed that in this experiment, tebuconazole suppressed the development of embryos at a relatively low concentration. In addition, mortality, malformation ratios, malformation patterns, and growth rates were similar to the results from the other assay systems. Therefore, tebuconazole was thought to have an effect on the embryo development of domestic frogs. In future, it will be necessary to identify species specificity in order to the clarify the causes of differences in mortality, malformation rate, and malformation patterns depending on the species.

• Ecology and Resilient Infrastructure
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• v.8 no.3
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• pp.135-142
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• 2021

Biopolymers have been known as eco-friendly soil strengthening materials and studied to apply levees. However, the effect of biopolymer on vegetation is not fully understood. In this study, we analyzed the root growth of Camelina sativa L. (Camelina) when the xanthan gum was amended to soil in Aluminum (Al) stress conditions. Amendment of 0.05% xanthan gum increased root growth of Camelina under Al stress conditions. Under the Al stress condition, expression of aluminum activate malate transporter 1 (ALMT1) gene of Camelina root was induced but showed a lower level of expression in xanthan gum amended soil than non-amended soil. Additionally, the binding capacity of xanthan gum with Al ions in the solution was confirmed. Using morin staining and ICP-OES analysis, the Al content of the roots in the xanthan gum soil was lower than in the non-xanthan gum soil. These results suggest that xanthan gum amended soils may reduce the detrimental effects of Al on the roots and positively affect the growth of plants. Therefore, xanthan gum is not only an eco-friendly construction material but also can protect the roots in the disadvantageous environment of the plant.

• Journal of Life Science
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• v.31 no.4
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• pp.430-441
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• 2021

Sesquiterpene lactones (STLs) are terpenoids found mostly in the Asteraceae family and are known for their strong cytotoxic properties, among other notable bioactivities. Some STLs, such as artemisinin and mipsagargin, are already commercially available and are used to fight malaria and tumor growth, respectively. Although the interest in STLs was low for a time after their discovery due to their toxic nature, past decades have witnessed a soar in STL-based studies focused on developing novel pharmaceuticals via chemical diversification. These studies have reported several promising physiological effects for STLs, including lower toxicity and diverse modes of action, and have demonstrated the antimicrobial, antioxidant, hepatoprotective, antiviral, antiprotozoal, phytotoxic, antitumor, and antiaging properties of STLs. STLs are mainly considered as valuable natural molecules for the fight against cancer since most STLs induce death of different types of cancer cells, as shown by in vitro and in vivo studies. Some STLs can also enhance the effects of drugs that are already in clinical use. Medicinal chemists use various STLs as starting molecules for the synthesis of new STLs or different bioactive compounds. All these developments warrant future research to provide more information on STLs, their bioactivities, and their mode of action. In this context, this review has summarized the bioactivities of some of the widely studied STLs, namely artemisinin, costunolide, thapsigargin, arglabin, parthenolide, alantolactone, cynaropicrin, helenalin, and santonin.

• Journal of fish pathology
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• v.34 no.2
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• pp.201-212
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• 2021

Olive flounder (Paralichthys olivaceus) (Weight 110.9±17.1 g, length 22.3±1.2 cm) were exposed to waterborne nitrite at 0, 30, 60, 120, 240, 480 and 960 mg NO₂^-/L according to water temperature at 20℃ and 25℃ for 96 hours. The lethal concentration 50 (LC₅₀) of olive flounder, P. olivaceus exposed to waterborne nitrite was 513.87 mg NO₂^-/L at 20℃ and 208.35 mg NO₂^-/L at 25℃, which means a significant difference in LC₅₀ by the water temperature. Hemoglobin and hematocrit were significantly decreased by waterborne nitrite exposure. The inorganic component, plasma calcium, was significantly decreased, and the organic components such as plasma glucose and cholesterol were significantly decreased showing a similar tendency with calcium. In enzymatic components, the AST and ALP were also significantly decreased by nitrite exposure. The results of this study indicate that exposure to nitrite can affect the survival and hematological physiology of P. olivaceus, and the effect of exposure to nitrite had a significant effect on nitrite toxicity depending on the water temperature.

• Journal of Convergence for Information Technology
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• v.11 no.12
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• pp.236-243
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• 2021

The aim of this study was to evaluate the anti-oxidant and anti-wrinkle effect of the black carrot(BC) extracted by supercritical dioxide(SC-CO₂). DPPH/ABTS radical scavenging and total polyphenol contents were measured to investigate the anti-oxidant activity of the BC supercritical extract. Collagen production and MMP-1 expression were assessed in normal human dermal fibroblasts(NHDF) for anti-wrinkle activity, The black carrot extract showed the highest total phenolic content(9.037±1.123 mg GAE/g extract) and the best antioxidant properties as shown by DPPH and ABTS assay. The supercritical fluid extracts of black carrot exhibited low toxicity to NHDF cells. In addition, the supercritical fluid extracts showed MMP-1 inhibition and type I pro-collagen synthesis inducing activities in a dose-dependent manner, respectively. Therefore, these results suggest that the black carrot is a potential source of high anti-oxidative, solvent-free and anti-aging material with promising applications in cosmetic, food, and beauty-food industries.

• Journal of Marine Life Science
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• v.4 no.1
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• pp.29-37
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• 2019

In order to control disease caused by multi-drug resistant bacteria in the aquaculture, the use of veterinary antibiotics, which are prohibited to fish, is increasing, instead of the existing fisheries antibiotics. Among them, tiamulin is illegally used in some cultured fish because it exhibits effective antibacterial activity against Gram-positive bacteria. To prevent unauthorized use, treatment of fish should be accompanied by a prescription from veterinarians or fisheries disease managers through research on fish of tiamulin. Tiamulin was injected intramuscularly at 5, 10 and 15 mg kg^-1 for the streptococcus-infected starry flounder, but did not show any therapeutic effect. Oral administration at a concentration of 15 and 30 mg kg^-1 was similarly ineffective. The concentrations of 30 and 60 mg kg^-1 resulted in death due to toxicity of antibiotics. Therefore, it is inappropriate to treat antibiotics with streptococcus-infected starry flounder.

• Journal of Marine Life Science
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• v.4 no.2
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• pp.45-52
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• 2019

Polycyclic aromatic hydrocarbons (PAHs) are persistent and commonly detected in marine ecosystem. They coexist with a various contaminants including heavy metals in real environment, but most studies have been still focused on single effects of these contaminants to aquatic organisms. In this study, the single and combined effects of benzy[a]pyrene (B[a]P) and HgCl₂ were investigated in the brackish water flea, Diaphanosoma celebensis. For combined effect study, three mixtures A (3:7), B (5:5), and C (7:3) of benzy[a]pyrene (B[a]P) and HgCl₂ were determined by 48 h - LC₅₀ values of single exposure. Combined effects of both chemicals were estimated by concentration addition (CA) model and independent action (IA) model. As results, 48 h - LC₅₀ values of benzy[a]pyrene (B[a]P) and HgCl₂ was 25.75 ㎍ l^-1 and 3.6 ㎍ l^-1, respectively. TU values of mixture A, B, and C were 1.06, 0.83, and 0.96, respectively, indicating additive effects of mixtures using CA model. This study will be helpful as basic data for understanding the combined effects of contaminants in marine environment.

• Korean Journal of Organic Agriculture
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• v.29 no.1
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• pp.97-109
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• 2021

Plant parasitic nematodes are causing significant damage in crop production. There is a need to develop eco-friendly nematicide that reduces the damage of nematode and has little effect on the environment and human. In this study, we have isolated a substance having nematicidal activity from Ginkgo biloba L. outer seedcoat. Studies of G. biloba L. outer seedcoat are insufficient compared to the seed and leaves due to their odor and toxicity. The dried G. biloba L. outer seedcoat was extracted with dichloromethane:methanol (1:1) and fractionated into hexane, ethyl acetate and H₂O. Four steps TLC were performed from EtOAc fraction to purely isolate GB4-3 with nematicidal activity. To compare nematicidal activity, G. biloba L. seedcoat methanol extract and purified GB4-3 were investigated in terms of treatment concentration and time. As a result, the nematicidal activity increased with concentration and time. In the place treated with 20 ㎍/mL of crude G. biloba L. seedcoat MeOH extract, strong activity appeared after 12 hours, and 46% nematicidal activity shown after 18 hours. About 69% of nematicidal activity was confirmed in the place where GB4-3 purified from outer seedcoat was treated with 20 ㎍/mL, and the possibility of development as nematicide was very high. This study could be used as a basic data for the development of a nematode preparation from G. biloba L. outer seedcoat.

• Journal of Environmental Health Sciences
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• v.47 no.2
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• pp.111-122
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• 2021

Objectives: There was a judgment of acquittal for the manufacturer SK Chemical and the vendor Aekyung regarding humidifier disinfectant (HD) containing 5-chloro-2-methylisothiazol-3(2H)-one/2-methylisothiazol-3(2H)-one (CMIT/MIT). The rationale used in this judgement is discussed here in the light of scientific consideration. Methods: The sentencing document for the judgements was obtained from the Korea Supreme Court Service. In particular, the judgements made by the court related to the risk of HD and external and internal exposure to CMIT/MIT are discussed based on scientific evidence. Results: Rendering a determination in a criminal trial of insufficient evidence of causation, the court dismissed the prosecution's motion that humidifier disinfectant-associated lung injuries (HDLI) and asthma were associated with the utilization of these products. However, CMIT/MIT, a strong sensitizing and corrosive substance, has been reported to be associated with brain toxicity, allergic contact dermatitis, and asthma. Furthermore, the judgment did not consider total consumption amounts or the cumulative dose of CMIT/MIT in the humidifier. Lastly, there are several cases supporting the fact that exposure to water-soluble substances including CMIT/MIT can cause lower respiratory tract diseases. In addition to cases of asthma among the workers exposed to CMIT/MIT, we identified lung injury victims who were exposed to HDs exclusively containing CMIT/MIT. Conclusions: We conclude that there is sufficient evidence supporting the assertion that HDs containing CMIT/MIT cause lung injuries, including asthma, contrary to the court's judgement.