Publications by authors named "Itayama Tomoaki"

Schistosomiasis, caused by trematodes of genus Schistosoma, is among the most seriously neglected tropical diseases. Although rapid surveillance of risk areas for Schistosoma transmission is vital to control schistosomiasis, the habitat and infection status of this parasite are difficult to assess. Environmental DNA (eDNA) analysis, involving the detection of extra-organismal DNA in water samples, facilitates cost-efficient and sensitive biomonitoring of aquatic environments and is a promising tool to identify Schistosoma habitat and infection risk areas.

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Delafloxacin (DFX), one of the latest additions to the fluoroquinolone antibiotics, is gaining heightened recognition in human therapy due to its potential antibacterial efficacy in a wide range of applications. Concerns have arisen regarding its presence in the environment and its potential interactions with multivalent metals, such as calcium (Ca). The present study investigated the trans- and multigenerational effects of environmentally projected concentrations of DFX (100-400 μg DFX L) on individual- and population-level responses of parental S.

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Microcystin-degrading bacteria first degrade microcystins by microcystinase A (MlrA) to cleave the cyclic structure of microcystins at the Adda-Arg site of microcystin-LR, microcystin-RR, and microcystin-YR, but the cleavage of the other microcystins was not clear. In our study, the microcystin-degrading bacterium sp. C-1 as wild type and that of -disrupting mutant, sp.

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Ciprofloxacin (CFX) and ofloxacin (OFX) are commonly found as residual contaminants in aquatic environments, posing potential risks to various species. To ensure the safety of aquatic wildlife, it is essential to determine the toxicity of these antibiotics and establish appropriate concentration limits. Additionally, in (eco)toxicological studies, addressing the issue of multiple hypothesis testing through -value adjustments is crucial for robust decision-making.

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To address the origins of ocean acidification, seaweed aquaculture is emerging as a key biosequestration strategy. Nevertheless, seaweed biomass is involved in developing food and animal feed, whereas seaweed waste from commercial hydrocolloid extraction is dumped in landfills, which together limit the carbon cycle and carbon sequestration. This work sought to evaluate the production, properties, and applications of seaweed compost and biochar to strengthen the "carbon sink" implications of aquaculture sectors.

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Article Synopsis
  • - Antibiotic-resistant bacteria pose a significant public health risk, and a new isolation method using 41 °C culture and specific primers was developed to evaluate their presence in the environment.
  • - In a study of 110 bacterial strains from a river, only 4% were antibiotic-resistant, compared to 35.7% of clinical strains from the same area, highlighting a stark difference between environmental and clinical bacteria.
  • - A high percentage of antibiotic-tolerance was found, with 78.8% in clinical strains and 90% in environmental strains, suggesting that environmental strains also carry a potential risk for infections, independent of their exposure to antibiotics.
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Remote communities in developing countries are facing ever-increasing water scarcities, due to cumulative demand induced by the climate change and global warming impacts. For the socio-economic and health well-being of the local communities, sufficient, efficient, and affordable water supply is fundamental from local-based adsorbents. Matamba Fruit shell was obtained and pyrolyzed to obtain well-transformed biochar, which exhibited enough capacity to remove Iodine from aqueous solution.

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Antibiotics, widely known as major environmental xenobiotics, are increasingly being released into ecosystems due to their essential functions in human health and production. During the COVID-19 pandemic waves, antibiotic use increases remarkably in treating bacterial coinfections. Antibiotics were initially expected only to affect prokaryotes, but recent research has shown that they can disturb the biological systems of eukaryotes, especially vulnerable aquatic creatures, through both direct and indirect processes.

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Conventional biological treatment has been reported to be ineffective for pollutant removal in tannery wastewater due to high salinity. To overcome it, this work used salt-tolerant bacteria (STB) isolated from a membrane bioreactor to evaluate the organic and nutrient removal through a series of batch experiments. Compared with the control, the STB reactor enhanced the reduction of persistent organics by 11% based on the double exponential decay model.

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Toxic cyanobacterial blooms frequently develop in eutrophic freshwater bodies worldwide. Microcystis species produce microcystins (MCs) as a cyanotoxin. Certain bacteria that harbor the mlr gene cluster, especially mlrA, are capable of degrading MCs.

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This study is aimed to comprehend the treatment of non-submerged attached growth systems using bio-sponge, bio-cord, and bio-cloth media. Three reactors were set up with internal recirculation ratio of 1 (IR = 1) and similar media surface area. Bio-sponge and bio-cloth reactors showed removal of COD (79 vs.

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Ciprofloxacin (CFX) and ofloxacin (OFX) are two of the most often used fluoroquinolone antibiotics, and their residues are found in large amounts in various aquatic settings. However, the toxicity tests of CFX using eukaryotic organisms such as Daphnia magna are inadequate, and the test result of OFX is currently unknown. Therefore, the chronic toxicity test for D.

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This study aims to offer insights into how ciprofloxacin (CIP) impact bacterial community structures in the Sponge-MBR process when CIP is spiked into hospital wastewater. We found that the CIP toxicity decreased richness critical phylotypes such as phylum class ẟ-, β-, ɣ-proteobacteria, and Flavobacteria that co-respond to suppress denitrification and cake fouling to 37% and 28% respectively. Cluster analysis shows that the different community structures were formed under the influence of CIP toxicity.

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This report describes the whole-genome sequence of a microcystin-degrading bacterium, sp. strain MD-1, isolated from a lake in Japan. The sp.

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This report describes the whole-genome sequence of an alkalitolerant microcystin-degrading bacterium, Sphingopyxis sp. strain C-1, isolated from a lake in China.

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A microfluidic device with analytical chambers for electrochemical measurements has been employed to detect photosynthetic activity at single cell level. The flowing cells (Microcystis viridis) in a main channel are individually guided to the chamber with microelectrodes by an electrophoretic manipulation. The reduction current of oxygen was continuously monitored to determine the photosynthetic activity upon light irradiation.

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The disease caused by cyprinid herpesvirus-3 (CyHV-3) severely impacts the natural freshwater ecosystem and damages carp and koi farming, however, the pathway of CyHV-3 transmission remains unclear. It is possible that the virus adheres to plankton, which then facilitate viral movement and transmission, and therefore, it is hypothesised that plankton are involved in the disease dynamics. In this study, plankton were collected at eight sites in the Iba-naiko lagoon; we detected and quantified CyHV-3 DNA from plankton samples.

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Endocrine disruptors that act like hormones in the endocrine system might have toxic effects. Therefore, it is important to develop a portable device that can detect hormone active chemicals in samples rapidly and easily. In this study, a microfluidic device was developed for the detection of hormone active chemicals using genetically engineered yeast cells.

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A pilot scale fluidized bed bioreactor to control the cyanobacterium, Microcystis, was tested in an outdoor experimental pond system (28 m3) over a 57 day period. The pond system was inoculated with a wild bloom of Microcystis, and the bioreactor was preinoculated with an oligochaete, Aeolosoma hemprichi, which is known to prey on colonial Microcystis. This and other Microcystis predators such as the rotifer, Philodina erythrophthalma were observed to colonize the bioreactor during the experiment.

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A novel microfluidic device with an array of analytical chambers was developed in order to perform single-cell-based gene-function analysis. A series of analytical processes was carried out using the device, including electrophoretic manipulation of single cells and electrochemical measurement of gene function. A poly(dimethylsiloxane) microstructure with a microfluidic channel (150 microm in width, 10 microm in height) and an analytical chamber (100 x 20 x 10 microm (3)) were fabricated and aligned on a glass substrate with an array of Au microelectrodes.

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The presence of cyanobacterial bloom in water supply reservoirs can cause potential health hazards. In this study, we aimed at the quantification of microcystin-producing cyanobacteria based on the microcystin synthetase A (mcyA) gene using real-time PCR. To perform a highly sensitive real-time PCR assay, the novel primer MSR-2R was designed and a coprecipitation DNA extraction method was used in this study.

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In order to make a breakthrough for the acute problem of water shortage in the world, the key words "decentralization and re-use" are very important for new sustainable sanitation systems that will be developed. Therefore, we focused on a new treatments system called "a slanted soil treatment system" which combines a biotoilet system with a domestic grey water treatment system. Because this system is a low cost and compact system, the system can be easily introduced to homes in urban areas or in the suburbs of cities in many developing countries.

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mlrA is the only microcystin-degrading gene detected in Sphingomonas sp. MJ-PV. The gene has an extremely rare nucleotide sequence and homologous genes have not yet been discovered in the DNA database.

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