著者

Masaya Matsuki Nobuhiro Shimizu Kazuhiro Tobiishi Yoshito Tanaka Haruyo Yamaguchi Tomoharu Sano

出版者

Japan Society on Water Environment

雑誌

Journal of Water and Environment Technology (ISSN:13482165)

巻号頁・発行日

vol.20, no.6, pp.261-272, 2022 (Released:2022-12-10)

参考文献数

34

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Cyanotoxins produced by blue-green algae in lakes are among the most serious threats to water quality worldwide. As global warming rapidly extends the locations and timing of blue-green algae blooms, a simple and accessible method for the detection and quantification of cyanotoxins in fresh water is increasingly necessary. Here, a quick, simple and accessible simultaneous analytical method for five cyanotoxins (cylindrospermopsin, anatoxin-a, microcystin-RR, YR and LR) is reported. This method has three advantages. First, it does not require complicated operations, such as a concentration operation. Second, it employs an HPLC column without high pressure. Third, the use of stable isotope-labeled surrogates enables correct identification and precise quantification of cyanotoxins. The method was applied to the lakes of Fukuoka Prefecture in Japan, and four of the five above-named cyanotoxins (i.e., all but cylindrospermopsin) were detected. The limits of quantification were 20–43 ng/L, which were considerably lower than the WHO guideline values. The recovery levels were 97–104%. Microbial flora analysis revealed that the sources of anatoxin-a were Pseudanabaena limnetica and Cuspidothrix issatschenkoi, and the source of microcystins was the group A1 of Microcystis aeruginosa. This study provides a quick, easy and accessible method for the worldwide monitoring of cyanotoxin levels.

著者

Shuhei Ota Shigeshi Fuchida Haruyo Yamaguchi Takahiro Yamagishi Hiroshi Yamamoto Hiroshi Koshikawa Masanobu Kawachi

出版者

Japan Mendel Society, International Society of Cytology

雑誌

CYTOLOGIA (ISSN:00114545)

巻号頁・発行日

vol.87, no.2, pp.177-187, 2022-06-25 (Released:2022-06-25)

参考文献数

41

被引用文献数

2

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Seafloor resource development in the future is expected to be accompanied by the mining of metal ores, as these sulfide ores contain valuable metals. However, the mining process is detrimental to marine oceanic environments. As a precautionary approach, innovations in the collection of environmental baseline data and new onboard assessment methods for marine environmental impacts are required. Due to the low cell density in open ocean water, techniques for rapid impact assessment of seawater without sample concentration are required. The purpose of this study was to establish a heavy metal impact assessment system for seawater samples of marine microbes using a portable flow cytometer, On-chip Sort. We established a protocol for detecting heavy metal-induced damage to cells via propidium iodide (PI) staining using algal culture strains (Bathycoccus prasinos NIES-2670, Synechococcus sp. NIES-969, Prochlorococcus sp. NIES-2885, and Cyanobium sp. NIES-981) obtained from the marine environment maintained at the Microbial Culture Collection of the National Institute for Environmental Studies, Tsukuba, Japan. Results showed that PI staining could detect the effects of heavy metals on cells. The proportion of PI-positive cells increased with an increase in the concentration of heavy metal mixture or copper exposure. Compared to cyanobacteria, damaged cells of eukaryotic algae were detected. Therefore, the effects of heavy metals on both eukaryotic and prokaryotic algae can be rapidly assessed via PI-based flow cytometry using samples containing low cell densities.