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| 1.
論文 |
論文
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Li, Ying ; Yoshida, Shota ; Chondo, Yvonne ; Nassar, Hossam ; Tang, Ning ; Araki, Yuki ; Toriba, Akira ; Kameda, Takayuki ; Hayakawa, Kazuichi
概要:
An on‑line concentration and fluorescence determination HPLC for polycyclic aromatic hydrocarbons (PAHs) in seawater was
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proposed. An online concentration column packed with octadecyl polyvinyl alcohol polymer, a pump and a column switching valve were introduced in the conventional HPLC with a fluorescence detector. Only 1.0–100 mL seawater sample was introduced into the concentration column at 1.0 mL min−1 without any other pretreatment except filtration. Then the trapped PAHs totally flew into the separation column and eluted separately to be detected fluorogenically. The proposed method had good linearity with correlation coefficients (r) ranged from 0.951 to 0.998, and limits of detection ranged from 0.002 to 0.50 ng L−1 for 15 PAHs as 100 mL seawater was loaded. The sensitivity of the method was 10 to 100 times higher than those reported by other works. The proposed method was applied to the determination of PAHs in the seawater samples collected in the Japan Sea with satisfactory results and to check the present benzo[a]pyrene concentration at the beaches in Noto peninsula, Japan polluted with C-heavy oil spilled from the tanker in 1997.
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| 2.
論文 |
論文
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Yamada, Maromu ; Nakamura, Kaya ; Kameda, Takayuki ; Kobayashi, Fumihisa ; Matsuki, Atsushi ; Tsuiki, Hisanaga ; Higaki, Seigo ; Iwasaka, Yasunobu ; Hayakawa, Kazuichi
概要:
Polycyclic aromatic hydrocarbons (PAHs) are known as carcinogenic and/or mutagenic substances, and are present at high c
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oncentration in polluted environments. It has recently been reported that spore-forming bacteria (e.g., Bacillus spp.) can be transported long distances alive in the atmosphere, which raises the possibility that some of the transported bacteria could have adverse effects on human health. There is thus a need for filters that can remove gaseous PAHs from the air that people breathe and that can inhibit bacterial growth on the filters. We focused on metallophthalocyanine derivatives (M-Pc) which are known to adsorb PAHs as well as to inhibit the growth of bacteria as a potential filtering agent. In this study, we developed different types of M-Pc-supported rayon fibers by changing central metals, functional groups, concentrations of M-Pc and rayon types, and evaluated their removal effects by measuring adsorption rates of 3- and 4-ring PAHs with a HPLC and growth curves of Bacillus sp. with a spectrophotometer. The results showed that both the effects depended on functional groups and concentrations of M-Pc, and rayon types. The most effective combination was observed in Fe-Pc with sulfo group supported on cationized rayon fiber at the concentration of 2 to 3.3 wt%. Central metal species of M-Pc were influenced only on the antibacterial properties. This fiber would be applicable to filtering agents and textiles.
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| 3.
論文 |
論文
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Hayakawa, Kazuichi ; Bekki, Kanae ; Yoshita, Morio ; Tachikawa, Chihiro ; Kameda, Takayuki ; Tang, Ning ; Toriba, Akira ; Hosoi, Shinzo
概要:
Estrogenic and antiestrogenic activities of 19 quinoid polycyclic aromatic hydrocarbons (PAHQs) and 9 ketone PAHs were e
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valuated by the yeast two-hybrid assay using yeast cells expressing estrogen receptor-α (ERα). Binding affinity of PAHQs to ERα was assayed by the polarized fluorescence method using FluormoneTM ES2. Ten PAHQs having 3-5 rings showed antiestrogenic activities. The most strongly antiestrogenic PAHQs were 1,4-chrysenequinone and 5,6-chrysenequinone. On the other hand, benzo[a]pyrene-3,6-quinone showed the strongest estrogenic activity. However, the other compounds tested did not show so strong estrogenic/antiestrogenic activities. Binding affinity to ER was required but not sufficient for estrogenic/antiestrogenic activities of PAHQs. The length-to-breadth ratios of the rectangular planes surrounding the ring molecules and the distances between the oxygen atom of the carbonyl group and farthest hydrogen atom of estrogenic/antiestrogenic PAHQs were in narrow ranges, suggesting a structure-activity relationship. As interactions between active PAHQ and ER, hydrogen bonding between carbonyl groups and amino acid residues and van der Waals forces were considered.
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