著者

Masayoshi Sano Ryosuke Makabe Ryo Matsuda Norio Kurosawa Masato Moteki

出版者

The Plankton Society of Japan, The Japanese Association of Benthology

雑誌

Plankton and Benthos Research (ISSN:18808247)

巻号頁・発行日

vol.17, no.4, pp.349-357, 2022-11-30 (Released:2022-11-30)

参考文献数

37

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Molecular analysis is a common tool for marine ecological and biological research. For genomic analysis of zooplankton, ethanol preservation and freezing are often used to preserve samples until analysis. However, these methods have disadvantages, such as the loss of morphological information. Recently, 10% Lugol’s iodine solution (10% Lugol) has been shown to be an effective preservative of plankton samples for molecular analysis, even after 18 months. However, that study only reported a PCR-based molecular study using copepods. We tested the preservation effectiveness of 10% Lugol on various zooplankton over 33 months by comparing them to samples preserved by freezing or in 5% formalin seawater. The results revealed that the total amounts of DNA extracted from crustacean and gelatinous zooplankton preserved in 10% Lugol were the same or higher than those preserved in formalin or by freezing. Gel electrophoresis of the extracted DNA indicated that the DNA of the samples preserved in 10% Lugol was not fragmented during the preservation period. PCR amplification of a partial 18S rRNA gene using DNA extracted from various zooplankton taxa (siphonophores, copepods, ostracods, doliolids, polychaetes, pteropods, euphausiids, and chaetognaths) was successful. Sequences of morphologically identified species preserved in 10% Lugol had BLAST hits to sequences of these species deposited in Genbank, with a similarity of 100%, which indicated there was no sequence alteration during the preservation period. Thus, we conclude that 10% Lugol is a suitable preservative for molecular analysis of various zooplankton taxonomic groups.

著者

Md Mehedi Iqbal Masahiko Nishimura Md. Nurul Haider Masayoshi Sano Minoru Ijichi Kazuhiro Kogure Susumu Yoshizawa

出版者

Japanese Society of Microbial Ecology / Japanese Society of Soil Microbiology / Taiwan Society of Microbial Ecology / Japanese Society of Plant Microbe Interactions / Japanese Society for Extremophiles

雑誌

Microbes and Environments (ISSN:13426311)

巻号頁・発行日

vol.36, no.4, pp.ME21037, 2021 (Released:2021-10-13)

参考文献数

81

被引用文献数

10

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Zostera marina (eelgrass) is a widespread seagrass species that forms diverse and productive habitats along coast lines throughout much of the northern hemisphere. The present study investigated the microbial consortia of Z. marina growing at Futtsu clam-digging beach, Chiba prefecture, Japan. The following environmental samples were collected: sediment, seawater, plant leaves, and the root-rhizome. Sediment and seawater samples were obtained from three sampling points: inside, outside, and at the marginal point of the eelgrass bed. The microbial composition of each sample was analyzed using 16S ribosomal gene amplicon sequencing. Microbial communities on the dead (withered) leaf surface markedly differed from those in sediment, but were similar to those in seawater. Eelgrass leaves and surrounding seawater were dominated by the bacterial taxa Rhodobacterales (Alphaproteobacteria), whereas Rhodobacterales were a minor group in eelgrass sediment. Additionally, we speculated that the order Sphingomonadales (Alphaproteobacteria) acts as a major degrader during the decomposition process and constantly degrades eelgrass leaves, which then spread into the surrounding seawater. Withered eelgrass leaves did not accumulate on the surface sediment because they were transported out of the eelgrass bed by wind and residual currents unique to the central part of Tokyo Bay.