• Journal of Microbiology and Biotechnology
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• v.18 no.2
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• pp.314-321
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• 2008

Acaricidal effects of materials derived from Diospyros kaki roots against Dermatophagoides farinae and D. pteronyssinus were assessed using impregnated fabric disk bioassay and compared with that of the commercial benzyl benzoate. The observed responses varied according to dosage and mite species. The $LD_{50}$ values of the chloroform extract of Diospyros kaki roots were 1.66 and $0.96{\mu}g/cm^2$ against D. farinae and D. pteronyssinus. The chloroform extract of Diospyros kaki roots was approximately 15.2 more toxic than benzyl benzoate against D. farinae, and 7.6 times more toxic against D. pteronyssinus. Purification of the biologically active constituent from D. kaki roots was done by using silica gel chromatography and high-performance liquid chromatography. The structure of the acaricidal component was analyzed by GC-MS, $^1H-NMR,\;^{13}C-NMR,\;^1H-^{13}C$ COSY-NMR, and DEPT-NMR spectra, and identified as plumbagin. The acaricidal activity of plumbagin and its derivatives (naphthazarin, dichlon, 2,3-dibromo-1,4-naphthoquinone, and 2-bromo-1,4-naphthoquinone) was examined. On the basis of $LD_{50}$ values, the most toxic compound against D. farinae was naphthazarin $(0.011{\mu}g/cm^2)$ followed by plumbagin $(0.019{\mu}g/cm^2),$ 2-bromo-1,4-naphthoquinone $(0.079{\mu}g/cm^2)$, dichlon $(0.422{\mu}g/cm^2)$, and benzyl benzoate $(9.14{\mu}g/cm^2)$. Additionally, the skin color of the dust mites was changed from colorless-transparent to dark brown-black by the treatment of plumbagin. Similar results have been exhibited in its derivatives (naphthazarin, dichlon, and 2-bromo-1,4-naphthoquinone). In contrast, little or no discoloration was observed for benzyl benzoate. From this point of view, plumbagin and its derivatives can be very useful for the potential control agents, lead compounds, and indicator of house dust mites.

• Environmental Analysis Health and Toxicology
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• v.30 no.sup
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• pp.3.1-3.11
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• 2015

Objectives This study presents the indicators and proxy variables for the quantitative assessment of green chemistry technologies and evaluates the relative importance of each assessment element by consulting experts from the fields of ecology, chemistry, safety, and public health. Methods The results collected were subjected to an analytic hierarchy process to obtain the weights of the indicators and the proxy variables. Results These weights may prove useful in avoiding having to resort to qualitative means in absence of weights between indicators when integrating the results of quantitative assessment by indicator. Conclusions This study points to the limitations of current quantitative assessment techniques for green chemistry technologies and seeks to present the future direction for quantitative assessment of green chemistry technologies.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1394-1398
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• 2007

Acaricidal activity of the active constituent derived from Pyrus ussuriensis fruits against Dermatophagoides farinae and D. pteronyssinus was examined and compared with that of the commercial benzyl benzoate. The $LD_{50}$ value of the ethyl acetate fraction obtained from the aqueous extract of P. ussuriensis fruits was 9.51 and $8.59{\mu}g/cm^3$ against D. farinae and D. pteronyssinus, respectively. The active constituent was identified as quinone by spectroscopic analyses. On the basis of $LD_{50}$ values with quinone and its congeners, the compound most toxic against D. farinae was quinone ($1.19{\mu}g/cm^3$), followed by quinaldine (1.46), benzyl benzoate (9.32), 4-quinolinol (86.55), quinine (89.16), and 2-quinolinol (91.13). Against D. pteronyssinus, these were quinone ($1.02{\mu}g/cm^3$), followed by quinaldine (1.29), benzyl benzoate (8.54), 4-quinolinol (78.63), quinine (82.33), and 2-quinolinol (86.24). These results indicate that the acaricidal activity of the aqueous extracts can be mostly attributed to quinone. Quinone was about 7.8 and 8.4 times more toxic than benzyl benzoate against D. farinae and D. pteronyssinus. Additionally, quinaldine was about 6.4 and 6.6 times more toxic than benzyl benzoate against D. farinae and D. pteronyssinus, respectively. Furthermore, the skin color of the dust mites was changed from colorless-transparent to dark brown-black by the treatment of quinone. These results indicate that quinone can be very useful as potential control agents, lead compounds, or the indicator of house dust mites.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1591-1596
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• 2006

Acaricidal effects of materials derived from Caesalpinia sappan heartwoods against Dermatophagoides farinae and D. pteronyssinus were assessed and compared with those evidenced by commercial benzyl benzoate and DEET. The observed responses varied according to dosage and mite species. The $LD_{50}$ values of the methanol extracts derived from C. sappan heartwoods were 6.13 and $5.44{\mu}g/cm^3$ against D. farinae and D. pteronyssinus, respectively. Furthermore, the ethyl acetate fraction derived from the methanol extract was approximately 8.71 more toxic than DEET against D. farinae, and 4.73 times more toxic against D. pteronyssinus. The biologically active constituent from the ethyl acetate fraction of C. sappan heartwood extract was purified via silica gel chromatography and high-performance liquid chromatography. The structure of the acaricidal component was analyzed by $GC-MS,\;^1H-NMR,\;^{13}C-NMR,\;^1H-^{13}C\;COSY-NMR$, and DEPT-NMR spectroscopy, and identified as juglone (5-hydroxy-l,4-naphthoquinone). Based on the $LD_{50}$ values of juglone and its derivatives, the most toxic compound against D. farinae was juglone ($0.076{\mu}g/cm^3$), followed by benzyl benzoate ($9.143{\mu}g/cm^3$) and 2methyl-l,4-naphthoquinone ($40.0{\mu}g/cm^3$). These results indicate that the acaricidal activity of C. sappan heartwoods is likely to be the result of the effects of juglone. Additionally, juglone treatment was shown to effect a change in the color of the cuticles of house dust mites, from colorless-transparent to dark brownish-black. Accordingly, as a naturally occurring acaricidal agent, C. sappan heartwood-derived juglone should prove to be quite 'useful as a potential control agent, lead compound, and house dust mite indicator.

• Fisheries and Aquatic Sciences
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• v.13 no.3
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• pp.236-243
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• 2010

Fecal sterols, nonylphenolic compounds (NPs), and polycyclic aromatic hydrocarbons (PAHs) were determined in surface water from Masan Bay and its adjacent rivers in February 2005. Concentrations of coporstanol (Cop), an indicator of fecal pollution, in surface water ranged from <10 to 13,853 ng/L, and concentrations of nonylphenol, the most toxic of the NPs, ranged from 10.2 to 481 ng/L, and concentrations of PAHs ranged from 8.61 to 223 ng/L. The concentrations of the compounds measured in this study were lower than or comparable to those at other locations in Korea and other countries. The contamination of Cop and PAHs in surface water was associated with the discharge from rivers passing through cities and/or industrial complexes. The NP contamination was associated with wastewater treatment plant (WWTP) effluents through outfalls as well as riverine discharge. Compared to ecotoxicological values, the concentrations of NPs from rivers, the mouths of rivers, and WWTP outfall areas exceeded guidelines, suggesting that hot spot areas may pose a potential risk to sensitive species.

• Korean Journal of Environmental Biology
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• v.42 no.1
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• pp.54-61
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• 2024

The ecosystem provides a diverse array of environmental conditions for organisms, and only those that are capable of successfully adapting to these conditions within their habitats can endure, thrive, and proliferate. Further, the environmental conditions within these habitats can significantly affect the bioavailability of chemicals that are introduced therein, thus resulting in varied adverse impacts on the organisms. The present study aims to evaluate the sensitivity of Yuukianura szeptyckii - a species adapted to riparian - to heavy metals following ISO guideline 11276, with the objective of assessing its potential as an indicator species for ecotoxicological evaluations in riparian habitats. The findings revealed that cadmium and copper both had significant toxic effects depending on their concentrations. For cadmium, the LC₅₀ was 280 mg kg^-1, EC₅₀ was 66 mg kg^-1, and NOEC and LOEC were 25 and 50 mg kg^-1, respectively. For copper, the LC₅₀ was 911 mg kg^-1, EC₅₀ was 151 mg kg^-1, and LOEC was 50 mg kg^-1. Comparative analysis with previous results for the international standard species Folsomia candida and the domestic standard species Allonychiurus kimi indicated that Y. szeptyckii exhibited even greater sensitivity to toxicity values. The adverse effects on survival and reproduction were closely associated with the influx concentration of heavy metals in their bodies. Altogether, the results suggest that Y. szeptyckii is a sensitive species for ecotoxicological assessments in riparian habitats, thus making it suitable as an indicator species, particularly in riparian ecosystems that are characterized by relatively high humidity conditions.

• Korean Journal of Veterinary Research
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• v.36 no.4
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• pp.873-886
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• 1996

For better understanding the interrelationship of hemorrhage and aggregation mechanism, cyclopiazonic acid(CPA) known as promoting the aggregation of platelet, aflatoxin $B_1(AFB_1)$ inhibiting platelet aggregation were used as toxic mycotoxins in these studies. In order to investigate the potential role of prostaglandin metabolism on the platelet aggregation, a variety of prostaglandin metabolites such as $PGF_{2{\alpha}}$, $PGE_2$ and $TXB_2$ were measured in homogenized rabbit platelets by TLC and LSC. And the role of $Ca^{{+}{+}}$ on the platelet aggregation was investigated by flow cytometer. Finally, the morphological effects of mycotoxins on platelet were determined by transmission electron microscope. The results and conclusions obtained from these studies are: 1) CPA induced no changes but $AFB_1$ increased $PGE_2$ and $TXB_2$. 2) CPA promoted ADP, collagen, thrombin, A.A., and PAF-induced $Ca^{{+}{+}}$ release. $AFB_1$, however, decreased $Ca^{{+}{+}}$ level except collagen-induced $Ca^{{+}{+}}$ release. When the calcium blocker, verapamil, was used, CPA decreased thrombin-induced $Ca^{{+}{+}}$ release and increased collagen, ADP, PAF and A.A.-induced $Ca^{{+}{+}}$ release. $AFB_1$ in contrast decreased the all factors induced $Ca^{{+}{+}}$ release. 3) $AFB_1$ did not induce any ultrastructural changes except large vacuole formation in a few platelets. And CPA also did not induce any changes except moderate shape change, indicator of platelet activation. In conclusion, CPA promoted platelet aggregation by the increases of $Ca^{{+}{+}}$ release but had no changes in A.A. metabolites. Antiaggregating effects of $AFB_1$ may be due to decreases of $Ca^{{+}{+}}$ release and increases of $PGE_2$ and $PGF_{2{\alpha}}$ formation. These data provide the basis for the future study of mobilization and function of $Ca^{{+}{+}}$ in platelet aggregation.