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| 1.
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Bekki, Kanae ; Toriba, Akira ; Ning, Tang ; Kameda, Takayuki ; Hayakawa, Kazuichi ; 戸次, 加奈江 ; 鳥羽, 陽 ; 唐, 寧 ; 亀田, 貴之 ; 早川, 和一
概要:
金沢大学理工研究域自然システム学系<br />Polycyclic aromatic hydrocarbons (PAHs) are included in various environmental pollutants such as
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airborne particles and have been reported to induce a variety of toxic effects. On the other hand, PAH derivatives are generated from PAHs both through chemical reaction in the atmosphere and metabolism in the body.PAH derivatives have become known for their specific toxicities such as estrogenic/antiestrogenic activities and oxidative stress, and correlations between the toxicities and structures of PAH derivatives have been shown in recent studies. These studies are indispensable for demonstrating the health effects of PAH derivatives, since they would contribute to the comprehensive toxicity prediction of many kinds of PAH derivatives.<br />多環芳香族炭化水素類（PAHs）は大気粉塵などの多種類の環境汚染物質に含まれ，長年の研究によって多様な生体影響を引き起こすことが知られている．一方で，PAHsは生体内での代謝反応や，大気中での化学反応によって多種多様な誘導体を生成することが知られている．近年では，PAHだけでなくPAH誘導体の毒性影響が着目されており，エストロゲン様/抗エストロゲン作用，酸化ストレス反応など，PAHとは異なる誘導体独自の毒性影響の存在が報告されている．また，生成するPAH誘導体には多くの構造異性体が存在するが，PAH誘導体が示す毒性作用と構造との間に相関性，いわゆる構造活性相関があることが示されている．以上の研究は，環境中に存在するPAH 誘導体の生体影響を解明する上で重要な研究であるとともに，多種多様なPAH誘導体の総合的な毒性影響予測に貢献できると考えられる．
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| 2.
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Kakimoto, Kensaku ; Toriba, Akira ; Ohno, Takanori ; Ueno, Mariko ; Kameda, Takayuki ; Tang, Ning ; Hayakawa, Kazuichi
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金沢大学医薬保健研究域薬学系<br />To evaluate human exposure to polycyclic aromatic hydrocarbons (PAHs), we developed a rapid, simple
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and sensitive method for determining 1-hydroxypyrene-glucuronide (1-OHP-G) in human urine. To improve precision, a deuterated glucuronide was used as an internal standard. The method requires only 1 mL of urine. The urine was treated with a mixed-mode anion-exchange and reversed-phase solid-phase extraction cartridge (Oasis MAX). The analytes were analyzed with a C18 reversed-phase column with a gradient elution, followed by tandem mass spectrometry with electrospray ionization in negative ion mode. The detection limit of 1-OHP-G (corresponding to a signal-to-noise ratio of 3) was 0.13 fmol/injection. Urinary concentrations of 1-OHP-G determined by this method were strongly correlated (r2 = 0.961) with concentrations of 1-hydroxypyrene by conventional HPLC with fluorescence detection. © 2008 Elsevier B.V. All rights reserved.
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| 3.
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Hosozumi, Chiemi ; Toriba, Akira ; Chuesaard, Thanyarat ; Kameda, Takayuki ; Tang, Ning ; Hayakawa, Kazuichi
概要:
Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) is a widely used noninvasive biomarker of oxidative stress. A selective, se
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nsitive and rapid method for determining 8-OHdG in human urine was developed using hydrophilic interaction chromatography-tandem mass spectrometry (HILIC-MS/MS) with electrospray ionization. 8-OHdG and isotopically labeled 8-OHdG (internal standard) were separated on a HILIC column with a mobile phase of 10. mM ammonium acetate: acetonitrile (1:9, v/v) within 10. min and detected by using a positive electrospray ionization interface under the selected reaction monitoring mode. The detection limits of 8-OHdG (corresponding to a signal-to-noise ratio of 3) for the HILIC-MS/MS system and the conventional method using a reversed-phase column with MS/MS were 1.0 and 26.0. fmol/injection, respectively. The proposed method makes it possible to monitor the basal level of urinary 8-OHdG from non-exposed healthy subjects and can be used for large-scale human studies. © 2012 Elsevier B.V.
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Tang, Ning ; Tokuda, Takahiro ; Izzaki, Akihiko ; Tamura, Kenji ; Ji, Ruonan ; Zhang, Xuemei ; Dong, Lijun ; Kameda, Takayuki ; Toriba, Akira ; Hayakawa, Kazuichi
概要:
Airborne particulates were collected in three size fractions by using Anderson low-volume air samplers in Shenyang, Chin
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a, in winter and summer in 2007. Compared with data obtained in 2001 at the same sites, the total concentrations of nine polycyclic aromatic hydrocarbons (PAHs) in winter decreased by 67% at one site and decreased by 40% at the other site, while the total concentrations of four nitropolycyclic aromatic hydrocarbons (NPAHs) did not decrease. This suggests that environmental countermeasures begun in 2001 were effective in decreasing the concentration of PAHs. However, in summer, the concentrations of PAHs and NPAHs rose by the factors of 4 and 5, respectively, possibly because of an increase in the number of motor vehicles. © 2011 Taylor and Francis Group, LLC.
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| 5.
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Sugitate, Kuniyo ; Yamagami, Takashi ; Nakamura, Sadao ; Toriba, Akira ; Hayakawa, Kazuichi
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Fenthion, fenthion sulfoxide, fenthion oxon sulfoxide and fensulfothion showed two different mass spectra in GC/MS, depe
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nding on their concentrations. The base peaks shifted to lower levels by 1 m/z at lower concentration, and no retention time shifts were observed. The "shifted base peaks" were not obtained by a general EI fragmentation. The product ion scan spectra of the "shifted base peaks" were coincident with those of molecular ions of their corresponding sulfides. These phenomena can be ascribed to the conversion of sulfoxide into sulfide by the dominant deoxidation reaction than EI fragmentation in an ion source. Adding polyethylene glycol 300 (PEG300) into a test solution prevented sulfoxide deoxidation. © The Japan Society for Analytical Chemistry.
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| 6.
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Koyama, Kazuo ; Hirao, Takashi ; Toriba, Akira ; Hayakawa, Kazuichi
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The quality of starch-containing foods may be significantly impaired by contamination with very small amounts of α-amyla
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se, which can enzymatically hydrolyze the starch and cause viscosity loss. Thus, for quality control, it is necessary to have an analytical method that can measure low amylase activity. We developed a sensitive analytical method for measuring the activity of α-amylase (from Bacillus subtilis) in starch-containing foods. The method consists of six steps: (1) crude extraction of α-amylase by centrifugation and filtration; (2) α-amylase purification by desalting and anion-exchange chromatography; (3) reaction of the purified amylase with boron-dipyrromethene (BODIPY)-labeled substrate, which releases a fluorescent fragment upon digestion of the substrate, thus avoiding interference from starch derivatives in the sample; (4) stopping the reaction with acetonitrile; (5) reversed-phase solid-phase extraction of the fluorescent substrate to remove contaminating dye and impurities; and (6) separation and measurement of BODIPY fluorescence by HPLC. The proposed method could quantify α-amylase activities as low as 10mU/mL, which is enough to reduce the viscosity of starch-containing foods. © 2012 John Wiley & Sons, Ltd.
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| 7.
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Tang, Ning ; Sato, Kousuke ; Tokuda, Takahiro ; Tatematsu, Michiya ; Hama, Hirotaka ; Suematsu, Chikako ; Kameda, Takayuki ; Toriba, Akira ; Hayakawa, Kazuichi
概要:
Airborne particulates were collected at a background site (Wajima Air Monitoring Station; WAMS) on the Noto Peninsula, J
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apan from January 2006 to December 2007. 1-, 2-nitropyrenes (1-, 2-NPs) and 2-nitrofluoranthene (2-NFR), in the particulates were determined with a sensitive HPLC method with chemiluminescence detection. The average concentrations were higher in winter than in summer. A meteorological analysis indicated that the air samples collected in winter were transported mainly from Northeast China over the Japan Sea. Both the concentration ratios of 2-NFR to 1-NP and 1-NP to pyrene were similar to those in Shenyang in Northeast China which located along the air transportation route to WAMS, but not in Kanazawa which near WAMS. These results strongly suggest that most of the atmospheric 1-, 2-NPs and 2-NFR at WAMS in winter were long range transported from Northeast China. © 2014 Elsevier Ltd. All rights reserved.
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| 8.
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Tang, Ning ; Yoda, Yoshiko ; Otani, Naruhito ; Kameda, Takayuki ; Toriba, Akira ; Hayakawa, Kazuichi ; Shima, Masayuki
概要:
Twenty-one data sets composed of readings collected by atmospheric ozone monitors worn by individuals on their clothing
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and installed outside their home or office were collected using Ogawa passive ozone samplers in southeastern Hyogo prefecture, Japan from September 12 to 13, 2011. The concentrations of personal and outdoor ozone ranged from not detectable to 23.2 ppb and from 4.7 to 38.3 ppb, respectively. The mean concentration of personal exposure to ozone was 3.7 ppb and was significantly lower than that of outdoor ozone (18.5 ppb). This suggests that the concentrations of outdoor ozone affect personal ozone exposure. However, in this study, we found no correlation between the concentrations of personal ozone and the total time spent outdoors or the time of day the individual was outside. In contrast, the mean concentrations of outdoor ozone were similar to those of ozone measured at the 12 nearest Ambient Monitoring Stations (AMSs). However, when the AMS was situated near a main road, the regional ozone levels were underestimated.
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| 9.
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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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| 10.
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Tamura, Masayoshi ; Mochizuki, Naoki ; Nagatomi, Yasushi ; Harayama, Koichi ; Toriba, Akira
概要:
Fumonisin A-series (FAs) in a reference material of corn sample that was naturally contaminated with fumonisins was char
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acterized using high-resolution liquid chromatography-Orbitrap mass spectrometry (LC-Orbitap MS). Peaks for fumonisin B1 (FB1), fumonisin B2 (FB2), and fumonisin B3 (FB3), in addition to three peaks corresponding to unknown compounds I, II, and III, were detected in the chromatogram for the corn sample. Fragment ion analysis for FB1, FB2, and FB3 showed that while the ions formed at m/z values of 200-800 were similar to those formed by the cleavage of the tricarballylic acids and the hydroxyl groups, the fragmentation patterns at m/z values of 50-200 varied depending on the hydroxyl group locations in the compounds. Fragment ion analysis of compounds I-III revealed structural similarities to FBs, only differing by an additional C<inf>2</inf>H<inf>2</inf>O in the unknown compounds. Using these results and by comparing the product ion mass spectra of compound I with fumonisin A1 (FA1) synthesized from FB1 standards, compounds I-III were hypothesized to be N-acetyl analogs of FBs: fumonisins A1 (FA1), A2 (FA2), and A3 (FA3). The method for determining concentrations was validated with FA1, FB1, FB2, and FB3 standards and applied to analyze the reference material. The FB1, FB2, and FB3 analytical levels were within acceptance limits and the amount of FA1 in the material was ~15% of FB1 amount at 4.2 mg/kg. © 2014 by the authors; licensee MDPI, Basel, Switzerland.
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