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The environmental impact of increased eutrophication and frequent cyanobacterial blooms on the growth and reproduction of aquatic organisms has become increasingly prominent in recent years. Bellamya aeruginosa is a nutrient-rich aquatic snail consumed by humans, and environmental changes may decrease its meat quality. However, the specific characteristics of muscle metabolism and flavor quality in freshwater snails and their response patterns to bloom-forming cyanobacterial stress have not been reported. Therefore, in this study, alterations in metabolites in the snail muscle after following feeding on toxic Microcystis aeruginosa were investigated using untargeted metabolomics. A total of 1,128 metabolites were identified, and the metabolic pathways of unsaturated fatty acid biosynthesis and purine, glutathione, and glycerophospholipid metabolism in snails fed toxic cyanobacteria differed from those in snails fed Chlorella vulgaris. Quantitative analysis showed increased levels of bitter-free amino acids, such as tyrosine, phenylalanine, and histidine, after consuming toxic cyanobacteria for 42 d, whereas a relative decrease was observed in the levels of umami- and sweet-free amino acids, such as glutamic acid, aspartic acid, serine, threonine, and glicine. The muscles of snails fed toxic cyanobacteria exhibited higher hypoxanthine and hypoxanthine nucleoside and lower adenosine triphosphate, adenine nucleotide, adenine nucleoside diphosphate, and hypoxanthine nucleotide contents than those of snails fed C. vulgaris. Furthermore, increased metabolites, such as stearic acid, palmitic acid, and cytidine diphosphate choline, and decreased metabolites, such as docosapentaenoic acid, docosahexaenoic acid, adrenoic acid, and L-glutamic acid, reflect the harmful effects of toxic cyanobacteria on the nutritional value and flesh quality of B. aeruginosa. This study comprehensively evaluated the effects of cyanobacterial blooms on freshwater gastropods, providing an important theoretical basis for the quality, safety, and sustainable development of snails as food and related processing industries. [ABSTRACT FROM AUTHOR]

Purpose: The vertical distribution of phosphorus (P) can vary depending on specific environmental factors like type of water body, soil type, land management and bioturbating macrofauna. To investigate how the benthic macrofauna affects vertical P distribution in aquatic sediment, a mesocosm laboratory experiment was conducted by using two muluscans: Bellamya aeruginosa and Corbicula fluminea. Materials and method: A 21-day mesocosm experiment was conducted with natural assemblages of two benthic macroinvertebrates (B. aeruginosa and C. fluminea). The Standard Measurements and Testing (SMT) method was used to acquire the migration, distribution, and transformation of P forms in benthic sediment bioturbation. Results and discussion: Results showed that the bioturbation of the benthic animals affected the decomposition and transformation of organic P (OP) in the sediment. The OP content in the sediment treated with benthic animal groups decreased dramatically during the experiment (p < 0.05). The non-apatite-inorganic-P (NAIP), inorganic-P (IP), and total-P (TP) of all treatment groups in the sediment layers increased over the experimental period. Comparing the two forms of bioturbation exerted, that of C. fluminea was significantly stronger compared to B. aeruginosa and the control groups. The apatite P content increased significantly in the 0–1-cm layer, and a significant decrease was observed in the 1–2-cm layer of the sediment (p < 0.05). Conclusion: This study shows that the bioturbation forces created by benthic macroinvertebrates B. aeruginosa and C. fluminea have significant impacts on the vertical distribution and transformation of sediment P forms and that the bioturbation effects of the C. fluminea on migration/transformation of P forms was stronger compared to B. aeruginosa. [ABSTRACT FROM AUTHOR]

Gut microbes play a critical role in helping hosts adapt to external environmental changes and are becoming an important phenotype for evaluating the response of aquatic animals to environmental stresses. However, few studies have reported the role that gut microbes play after the exposure of gastropods to bloom-forming cyanobacteria and toxins. In this study, we investigated the response pattern and potential role of intestinal flora in freshwater gastropod Bellamya aeruginosa when exposed to toxic and non-toxic strains of Microcystis aeruginosa, respectively. Results showed that the composition of the intestinal flora of the toxin-producing cyanobacteria group (T group) changed significantly over time. The concentration of microcystins (MCs) in hepatopancreas tissue decreased from 2.41 ± 0.12 on day 7 to 1.43 ± 0.10 μg·g−1 dry weight on day 14 in the T group. The abundance of cellulase-producing bacteria (Acinetobacter) was significantly higher in the non-toxic cyanobacteria group (NT group) than that in the T group on day 14, whereas the relative abundance of MC-degrading bacteria (Pseudomonas and Ralstonia) was significantly higher in the T group than that in the NT group on day 14. In addition, the co-occurrence networks in the T group were more complex than that in the NT group at day 7 and day 14. Some genera identified as key nodes, such as Acinetobacter, Pseudomonas, and Ralstonia, showed different patterns of variation in the co-occurrence network. Network nodes clustered to Acinetobacter increased in the NT group from day 7 to day 14, whereas the interactions between Pseudomonas and Ralstonia and other bacteria almost changed from positive correlations in the D7T group to negative correlations in the D14T group. These results suggested that these bacteria not only have the ability to improve host resistance to toxic cyanobacterial stress by themselves, but they can also further assist host adaptation to environmental stress by regulating the interaction patterns within the community. This study provides useful information for understanding the role of freshwater gastropod gut flora in response to toxic cyanobacteria and reveals the underlying tolerance mechanisms of B. aeruginosa to toxic cyanobacteria. [ABSTRACT FROM AUTHOR]

The benthic gastropods Bellamya aeruginosa (B. aeruginosa) is ubiquitous in freshwater in China and neighboring countries with great edible value. It has been recognized as a potential manipulator to control harmful algal blooms due to its filtration on algal cells. In this study, the control effect of B. aeruginosa on toxic and non-toxic Microcystis aeruginosa (M. aeruginosa), and the accumulation and depuration of microcystins (MCs) in the snail were systematically explored. Results indicated that although toxic M. aeruginosa could protect itself via producing MCs, the introduction of B. aeruginosa could still effectively inhibit the algae with cell density below 1 × 106 cells/mL. Hepatopancreas was the primary target of MCs in all tissues of B. aeruginosa, presenting a maximum of 3089.60 ng/g DW when exposed to toxic M. aeruginosa of 1.0 × 107 cells/mL. The enrichment of MCs in other tissues following the order of digestive tract > gonad > mantle > muscle. Interestingly, snail could again excrete previously enriched MCs when transferred to non-toxic M. aeruginosa, giving rise to over 80% reduction of MCs in the body. After depuration, the estimated daily intake (EDI) of free MCs in intact individuals and the edible parts of B. aeruginosa were both lower than the tolerable daily intake (TDI). These results implicated that B. aeruginosa could control low density of M. aeruginosa in spring. Particularly, the snail could be perfectly safe to consume by purifying for a while after using as manipulator.

Frequent outbreaks of harmful cyanobacterial blooms and the cyanotoxins they produce not only seriously jeopardize the health of freshwater ecosystems but also directly affect the survival of aquatic organisms. In this study, the dynamic characteristics and response patterns of transcriptomes and gut microbiomes in gastropod Bellamya aeruginosa were investigated to explore the underlying response mechanisms to toxic cyanobacterial exposure. The results showed that toxic cyanobacteria exposure induced overall hepatopancreatic transcriptome changes. A total of 2128 differentially expressed genes were identified at different exposure stages, which were mainly related to antioxidation, immunity, and metabolism of energy substances. In the early phase (the first 7 days of exposure), the immune system may notably be the primary means of resistance to toxin stress, and it performs apoptosis to kill damaged cells. In the later phase (the last 7 days of exposure), oxidative stress and the degradation activities of exogenous substances play a dominant role, and nutrient substance metabolism provides energy to the body throughout the process. Microbiomic analysis showed that toxic cyanobacteria increased the diversity of gut microbiota, enhanced interactions between gut microbiota, and altered microbiota function. In addition, the changes in gut microbiota were correlated with the expression levels of antioxidant-, immune-, metabolic-related differentially expressed genes. These results provide a comprehensive understanding of gastropods and intestinal microbiota response to toxic cyanobacterial stress. [ABSTRACT FROM AUTHOR]

Simple Summary: The population genomic study of seven populations of Bellamya aeruginosa across three river systems in China was conducted by specific-locus amplified fragment sequencing (SLAF-seq). A clear division was found among populations from the Yellow River basin and the Pearl River basin, as well as population YC from the Yangtze River basin using the SNPs data. However, there existed no distinct population structure using the mitochondrial DNA. Anthropogenic translocation from the Yangtze River to the Pearl River basin and the passive dispersion from the Yangtze River basin to the Yellow River basin by flooding have weakened the phylogeographic pattern of B. aeruginosa. These results provide useful guidance for the effective selective breeding of Bellamya, which is very important for the development of the industry of LZRSRN. Clarifying the genetic structure can facilitate the understanding of a species evolution history. It is crucial for the management of germplasm resources and providing useful guidance for effective selective breeding. Bellamya is an economically and ecologically important freshwater snail for fish, birds and even humans. Population genetic structures of the Bellamya species, however, were unknown in previous studies. Population genomics approaches with tens to hundreds of thousands of single nucleotide polymorphisms (SNPs) make it possible to detect previously unidentified structures. The population genomic study of seven populations of B. aeruginosa across three river systems (Yellow River, Yangtze River and Pearl River) in China was conducted by SLAF-seq. SLAF-seq obtained a total of 4737 polymorphisms SLAF-tags and 25,999 high-consistency genome-wide SNPs. The population genetic structure showed a clear division among populations from the Yellow River basin (YH and WL) and the Pearl River basin (QSH and LB), as well as population YC from the Yangtze River basin using the SNPs data. However, there existed no distinct population structure using the mitochondrial DNA (mtDNA). The anthropogenic translocation from the Yangtze River basin to the Pearl River basin and the passive dispersion from the Yangtze River basin to the Yellow River basin by flooding have weakened the phylogeographic pattern of B. aeruginosa. The divergence of B. aeruginosa in the three river systems suggests that the anthropogenic dispersal for aquaculture and breeding requires serious consideration of the population structure for the preservation of genetic diversity and effective utilization of germplasm resources. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Hydrobiology is the property of Editorial Department of Journal of Hydrobiology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a hypertoxic natural toxin, the risk of Microcystin-leucine-arginine (MC-LR) residues in Bellamya aeruginosa deserves more attention. Herein, employing the conventional thin-layer chromatography (TLC) technology and a novel surface-enhanced Raman scattering (SERS) substrate, a TLC-SERS chip was fabricated for the purification and quantitative detection of MC-LR in complex samples. The substrate exhibited excellent SERS performance with an enhancement factor of 6.6 × 107, a low detection limit of 2.27 × 10−9 mM for MC-LR, excellent uniformity and reproducibility, as well as a wide linear range. With the application of TLC, the MC-LR was efficiently purified and the concentration was increased to >3 times. Ultimately, recovery rates fluctuated between 93.28% and 101.66% were obtained from the TLC-SERS chip. On balance, the TLC-SERS chip has a robust capacity for achieving rapid and stable quantitative detection of MC-LR, which promises to improve the efficiency of food safety monitoring. • A novel in-situ ZIF-67/Ag NPs/Au NWs SERS substrate was successful prepared. • A multifunctional TLC-SERS chip was fabricated combining the TLC process and SERS. • The TLC-SERS chip enables separation and quantitative detection of MC-LR. • The EF of the TLC-SERS chip was 6.6 × 107 and the LOD on MC-LR was 2.27 × 10−9 mM. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Applied Ecology / Yingyong Shengtai Xuebao is the property of Chinese Journal of Applied Ecology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Various indices based on metal chemical data are used to evaluate pollution and ecological risk, but the consistency of the assessment results is usually unsatisfactory, and it is unclear if the ecological risk from sediment metals is accurately represented in in situ zoobenthos. Herein, the pollution and ecological risk associated with As, Cd, Cr, Cu, Ni, Pb and Zn in the sediments of two adjacent lakes (Datun (DT) and Changqiao (CQ)) were comprehensively evaluated by integrating metal concentrations, chemical forms and bioaccumulation in Bellamya aeruginosa (B. aeruginosa). The metal concentrations and chemical compositions varied widely in the sediments. Over 50% of the Cd, Pb and Zn in the sediments was present in bioavailable forms, followed by 28% of Cu and less than 25% of As, Cr and Ni. According to the enrichment factor (EF) and concentration enrichment ratio (CER) assessments, Cr and Ni were natural in origin, while the other metals were at minor to extremely high pollution levels, with average EFs of 1.5–77.6 and CERs of 1.1–113.4. The pollution levels for Cd, Cu and Pb from the EF and CER assessments were similar, while those for As and Zn were higher according to CER than EF (p = 0.05), likely due to the baseline underestimation associated with the potential diagenetic remobilization of bioavailable metals. The ecological risk index (Er), sediment quality guidelines (SQGs) and risk assessment code (RAC) showed a high eco-risk for Cd, while no similar risk was found for the other metals. By integrating risk indices with the chemical forms and pollution levels of metals, we deduced high eco-risks for As and Pb and moderate eco-risks for Cu and Zn in DT Lake and moderate eco-risks for As, Pb and Zn in CQ Lake. The other metals in the sediments of the two lakes presented low eco-risks. No significant positive correlations (p = 0.05) between metal accumulation in B. aeruginosa and the indices of pollution and eco-risk were observed except for the case of As, implying that measuring the metal concentrations in B. aeruginosa would not accurately characterize the metal pollution and ecological risk of sediments.

Gut microbes play a critical role in helping hosts adapt to external environmental changes and are becoming an important phenotype for evaluating the response of aquatic animals to environmental stresses. However, few studies have reported the role that gut microbes play after the exposure of gastropods to bloom-forming cyanobacteria and toxins. In this study, we investigated the response pattern and potential role of intestinal flora in freshwater gastropod Bellamya aeruginosa when exposed to toxic and non-toxic strains of Microcystis aeruginosa, respectively. Results showed that the composition of the intestinal flora of the toxin-producing cyanobacteria group (T group) changed significantly over time. The concentration of microcystins (MCs) in hepatopancreas tissue decreased from 2.41 ± 0.12 on day 7 to 1.43 ± 0.10 μg·g−1 dry weight on day 14 in the T group. The abundance of cellulase-producing bacteria (Acinetobacter) was significantly higher in the non-toxic cyanobacteria group (NT group) than that in the T group on day 14, whereas the relative abundance of MC-degrading bacteria (Pseudomonas and Ralstonia) was significantly higher in the T group than that in the NT group on day 14. In addition, the co-occurrence networks in the T group were more complex than that in the NT group at day 7 and day 14. Some genera identified as key nodes, such as Acinetobacter, Pseudomonas, and Ralstonia, showed different patterns of variation in the co-occurrence network. Network nodes clustered to Acinetobacter increased in the NT group from day 7 to day 14, whereas the interactions between Pseudomonas and Ralstonia and other bacteria almost changed from positive correlations in the D7T group to negative correlations in the D14T group. These results suggested that these bacteria not only have the ability to improve host resistance to toxic cyanobacterial stress by themselves, but they can also further assist host adaptation to environmental stress by regulating the interaction patterns within the community. This study provides useful information for understanding the role of freshwater gastropod gut flora in response to toxic cyanobacteria and reveals the underlying tolerance mechanisms of B. aeruginosa to toxic cyanobacteria.

Freshwater gastropods are widely distributed and play an important role in aquatic ecosystems. Symbiotic microorganisms represented by gut microbes can affect the physiological and biochemical activities of their hosts. However, few studies have investigated the response of the gut microbial community of snails to environmental stress. In this study, the dynamics of the gut microbiota of the gastropod Bellamya aeruginosa were tracked to explore their responses in terms of their composition and function to cyanobacterial bloom. Differences in gut microbial community structures during periods of non-cyanobacterial bloom and cyanobacterial bloom were determined. Results showed that the alpha diversity of the gut microbiota exposed to cyanobacterial bloom was lower than that of the gut microbiota exposed to non-cyanobacterial bloom. The main genera differentiating the two periods were Faecalibacterium, Subdoligranulum, Ralstonia , and Pelomonas. Microcystins (MCs) and water temperature (WT) were the primary factors influencing the gut microbial community of B. aeruginosa ; between them, the influence of MCs was greater than that of WT. Fourteen pathways (level 2) were notably different between the two periods. The pathways of carbohydrate metabolism, immune system, environmental adaptation, and xenobiotics biodegradation and metabolism in these differential pathways exhibited a strong linear regression relationship with MCs and WT. Changes in the functions of the gut microbiota may help B. aeruginosa meet its immunity and energy needs during cyanobacterial bloom stress. These results provide key information for understanding the response pattern of freshwater snail intestinal flora to cyanobacterial blooms and reveal the underlying environmental adaptation mechanism of gastropods from the perspective of intestinal flora. [ABSTRACT FROM AUTHOR]

Freshwater gastropods are widely distributed and play an important role in aquatic ecosystems. Symbiotic microorganisms represented by gut microbes can affect the physiological and biochemical activities of their hosts. However, few studies have investigated the response of the gut microbial community of snails to environmental stress. In this study, the dynamics of the gut microbiota of the gastropod Bellamya aeruginosa were tracked to explore their responses in terms of their composition and function to cyanobacterial bloom. Differences in gut microbial community structures during periods of non-cyanobacterial bloom and cyanobacterial bloom were determined. Results showed that the alpha diversity of the gut microbiota exposed to cyanobacterial bloom was lower than that of the gut microbiota exposed to non-cyanobacterial bloom. The main genera differentiating the two periods were Faecalibacterium, Subdoligranulum, Ralstonia, and Pelomonas. Microcystins (MCs) and water temperature (WT) were the primary factors influencing the gut microbial community of B. aeruginosa; between them, the influence of MCs was greater than that of WT. Fourteen pathways (level 2) were notably different between the two periods. The pathways of carbohydrate metabolism, immune system, environmental adaptation, and xenobiotics biodegradation and metabolism in these differential pathways exhibited a strong linear regression relationship with MCs and WT. Changes in the functions of the gut microbiota may help B. aeruginosa meet its immunity and energy needs during cyanobacterial bloom stress. These results provide key information for understanding the response pattern of freshwater snail intestinal flora to cyanobacterial blooms and reveal the underlying environmental adaptation mechanism of gastropods from the perspective of intestinal flora.

Molluscan metabolomic analysis is essential for the understanding of the regulatory mechanism of aquatic invertebrate in response to hepatotoxic microcystins (MCs) stress. To understand the system responses of the gastropod to MC exposure, metabolomic alterations caused by two strains (MC-producing and non MC-producing) of Microcystis aeruginosa were characterized indifferent biological matrices (hepatopancreas and muscle) of Bellamya aeruginosa (Gastropoda) using 1H nuclear magnetic resonance (NMR) spectroscopy combined with MCs detections after exposure for 1, 7, and 14 d. Although ELISA analysis showed that no MCs was detected in both tissues after non MC-producing M. aeruginosa exposure, MCs concentrations were increasing in the hepatopancreas (from 1.29±0.48 μg/g to 3.17±0.11 μg/g) and foot muscle (from 0.07±0.02 μg/g to 0.21±0.08 μg/g) after 14-d exposure of MC-producing M. aeruginosa. Meanwhile, we observed that MC induced significant increase in creatine, a variety of amino acids (leucine, isoleucine, valine, threonine, alanine, methionine, glutamate, aspartate, and lysine), carboxylic acids (lactate, acetate, and D-3-hydroxybutyrate), and choline and its derivatives (phosphocholine and glycerophosphocholine) but decreased the energy substance (lipids, glucose, and glycogen) in the hepatopancreas. However, no significant metabolite differences were observed in the muscle between MC-producing and non MC-producing cyanobacteria treated groups. These results suggest that MC exposure may cause hepatic energy expenditure accompanied with various metabolic disorders that involve lipid metabolism, protein catabolism, osmoregulation, glycolysis, glycogenolysis, and tricarboxylic acid (TCA) cycle. Moreover, metabolic perturbation was aggravated as the level of accumulated MCs raised over time in the MC-producing cyanobacteria treatment. These findings indicated that MCs accumulation might lead to oxidative-stress-mediated damage of mitochondria functions. [ABSTRACT FROM AUTHOR]

Frequent outbreaks of harmful cyanobacterial blooms and the cyanotoxins they produce not only seriously jeopardize the health of freshwater ecosystems but also directly affect the survival of aquatic organisms. In this study, the dynamic characteristics and response patterns of transcriptomes and gut microbiomes in gastropod Bellamya aeruginosa were investigated to explore the underlying response mechanisms to toxic cyanobacterial exposure. The results showed that toxic cyanobacteria exposure induced overall hepatopancreatic transcriptome changes. A total of 2128 differentially expressed genes were identified at different exposure stages, which were mainly related to antioxidation, immunity, and metabolism of energy substances. In the early phase (the first 7 days of exposure), the immune system may notably be the primary means of resistance to toxin stress, and it performs apoptosis to kill damaged cells. In the later phase (the last 7 days of exposure), oxidative stress and the degradation activities of exogenous substances play a dominant role, and nutrient substance metabolism provides energy to the body throughout the process. Microbiomic analysis showed that toxic cyanobacteria increased the diversity of gut microbiota, enhanced interactions between gut microbiota, and altered microbiota function. In addition, the changes in gut microbiota were correlated with the expression levels of antioxidant-, immune-, metabolic-related differentially expressed genes. These results provide a comprehensive understanding of gastropods and intestinal microbiota response to toxic cyanobacterial stress.

Clarifying the genetic structure can facilitate the understanding of a species evolution history. It is crucial for the management of germplasm resources and providing useful guidance for effective selective breeding. Bellamya is an economically and ecologically important freshwater snail for fish, birds and even humans. Population genetic structures of the Bellamya species, however, were unknown in previous studies. Population genomics approaches with tens to hundreds of thousands of single nucleotide polymorphisms (SNPs) make it possible to detect previously unidentified structures. The population genomic study of seven populations of B. aeruginosa across three river systems (Yellow River, Yangtze River and Pearl River) in China was conducted by SLAF-seq. SLAF-seq obtained a total of 4737 polymorphisms SLAF-tags and 25,999 high-consistency genome-wide SNPs. The population genetic structure showed a clear division among populations from the Yellow River basin (YH and WL) and the Pearl River basin (QSH and LB), as well as population YC from the Yangtze River basin using the SNPs data. However, there existed no distinct population structure using the mitochondrial DNA (mtDNA). The anthropogenic translocation from the Yangtze River basin to the Pearl River basin and the passive dispersion from the Yangtze River basin to the Yellow River basin by flooding have weakened the phylogeographic pattern of B. aeruginosa. The divergence of B. aeruginosa in the three river systems suggests that the anthropogenic dispersal for aquaculture and breeding requires serious consideration of the population structure for the preservation of genetic diversity and effective utilization of germplasm resources.

Microplastic pollution poses threats to aquatic ecosystems and human health. In this study, in order to investigate the characteristics of microplastic occurrence in different environmental media, the abundance, particle size, shape, color, and composition types of microplastics in the water column, sediment, riparian zone soil, and the benthic snail Bellamya aeruginosa of the Manao River were analyzed using field sampling, microscopic observation, and Fourier infrared spectroscopy. The results showed that the average abundance of microplastics in the surface water of the Manao River was (5.9±0.26) n·L -1 ; the abundance of microplastics in the upper sediment (by dry weight) was (1.35±0.1) n·g -1 , and that in the lower sediment (by dry weight) was (0.93±0.12) n·g -1 . The abundance of microplastics in the near riparian zone soil (by dry weight) was (0.68±0.16) n·g -1 , and that in the far riparian zone soil (by dry weight) was (0.69±0.14) n·g -1 , and the abundance of microplastics in the B. aeruginosa was (2.06±0.25) n·g -1 . The analysis results showed that the abundance of microplastics in the upper and lower sediments were positively correlated; the abundance of microplastics in B. aeruginosa was positively correlated with the abundance of microplastics in the upper and lower sediments, respectively; and the abundance of microplastics in the near and far riparian zone soils were also correlated. Most of the microplastics within each environmental medium and B. aeruginosa were <0.1 mm in size, mainly in the form of fibers and fragments, mainly blue and black in color, and mainly composed of polypropylene (PP) and polyethylene (PE). It was found that microplastics in riparian zone soils mainly originated from the fragmentation and decomposition of agricultural plastic films. The results of this study shed light on the accumulation of microplastics in macrobenthic organisms through the investigation of microplastics in multi-environmental media and in the B. aeruginosa , which helps us to understand the potential ecological risk of microplastics in a comprehensive manner.

Abstract Background Freshwater sediments have been recognized as a long-term sink and potential source for environmental pollutants released into the aquatic ecosystems. In this study, the sediment quality of Taihu Lake, which is susceptible to anthropogenic contamination, was assessed by a combination of chemical analytical and biological end points. Specifically, the snail Bellamya aeruginosa was caged in situ at two locations representing different pollution levels for different exposure times (7, 14 and 21 days). At each of these time points, biochemical parameters, i.e., phase I biotransformation enzymes ethoxyresorufin-O-deethylase (EROD), the antioxidant enzymes superoxide dismutase and catalase, reactive oxygen species, protein carbonyl content and lipid peroxidation, were evaluated in the hepatopancreas of snails. In addition, surface sediments were collected for analysis of contaminants of concern, including inorganic pollutants, organochlorine pesticides, polychlorinated biphenyls and polybrominated diphenyl ethers. Results Chemical analyses revealed that sediments from Taihu Lake were contaminated with trace elements and organic pollutants. Concentrations of trace elements (Cu, Ni and As) and organochlorinated pesticides (4,4′-DDE) exceeded their corresponding threshold effect level according to the sediment quality assessment values for freshwater ecosystems in Canada, indicating that adverse biological effects may occur. All biomarkers, except EROD activity, were induced in snails during all exposure times. The integrated biomarker response index (IBR) indicated that during the initial exposure phase (7 days), B. aeruginosa were subjected to significant environmental stress, which diminished during later sampling time points. Conclusions Results showed that IBR correlated well with the levels of environmental contaminants, demonstrating the applicability of this biomonitoring approach to complex environmental exposure scenarios.

Background: Sediments function as a secondary and significant source of tributyltin (TBT) and triphenyltin (TPT) in aquatic ecosystems and may pose a potential threat on benthic organisms and human health. The subchronic toxicity of sediment-associated TBT or TPT to snails Bellamya aeruginosa at environmentally relevant concentrations was investigated in this study. Multiple endpoints at the biochemical [ethoxyresorufin-O-deethylase (EROD), superoxide dismutase (SOD), catalase (CAT), protein carbonyl content (PCC) and lipid peroxidation (LPO)] and transcriptomic levels were examined. Results: TBT or TPT in sediment could induce antioxidant enzymes' activities and result in oxidative damage in the hepatopancreas of B. aeruginosa after 28-day exposure. A transcriptomic profile of B. aeruginosa exposed to TBT and TPT was reported. CYP genes and EROD activity were sensible and reliable biomarkers for toxicity assessment of TBT or TPT in sediments. Comparative pathway analysis revealed the alteration of steroid hormone biosynthesis and retinol metabolism in B. aeruginosa after 90-day exposure to sediment-associated TBT at the concentration of 2000 ng/g dw, which might affect both reproduction and lipogenesis functions. The ubiquitin proteasome system and immune system might be the toxicity target in B. aeruginosa after exposure to sediment-associated TPT for 90 days. Conclusions: The results offered new mechanisms underlying the toxicity of sediment-associated tributyltin and triphenyltin. [ABSTRACT FROM AUTHOR]

Field investigation and laboratory experiments were conducted to study the Pb and Cd tolerance mechanism of Bellamya aeruginosa from the Xiangjiang River. B. aeruginosa were collected from the middle reaches of the Xiangjiang River, and their Pb and Cd accumulation and subcellular distribution, as well as the related ecological risks, were analysed. Results showed significant differences between Pb and Cd accumulation and distribution in B. aeruginosa. Cd concentration was distributed in the following decreasing order: visceral mass > mantle > foot > shell, with the visceral mass and mantle being the main Cd accumulation sites. The shell was the main part accumulating Pb in B. aeruginosa, with Pb not being detected in soft tissues. Differential centrifugation revealed Cd subcellular distribution, i.e. lysosomes and mitochondria were the important accumulation and effect sites of Cd in B. aeruginosa cells. Cd subcellular distribution effectively reduced Cd damage on the nuclei, which improved the Cd tolerance of B. aeruginosa. The single factor pollution (Pi) and metal pollution (MPI) indices showed that the middle reaches of the Xiangjiang River had been seriously polluted by Pb and Cd. Cd pollution was particularly serious, accumulating in B. aeruginosa, which constituted a food safety hazard to humans. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Fluoroquinolones (FQs) present in water environments pose threats to aquatic organisms. The concentration of FQs adsorbed onto sediments is generally higher than that in water. Here, we studied the toxicities of two FQ antibiotics, norfloxacin (NOR) and ofloxacin (OFL), on the snail Bellamya aeruginosa, an adaptable benthic animal. For this, we performed acute toxicity experiments on young snails and sub-chronic exposure experiments on adult snails by exposure to the FQs for 1–28 days. The 96 h median effective concentrations showed that NOR toxicity was higher than OFL toxicity, although both NOR and OFL were low-toxicity substances (EC50 > 100 mg L−1). Four concentrations were used in the sub-chronic exposure experiments. Results of the measurement of bioconcentration factors (BCF) showed that OFL accumulation was higher than NOR accumulation in snail tissues. During the depuration period (28–49 days), at low concentrations (2 and 20 μg L−1), both FQs required at least 7 days to reach the maximum residue limit (50 μg kg−1). Conversely, at high concentrations (200 and 2000 μg L−1), 14 days (NOR) and 21 days (OFL) were required. Our results could facilitate management of the environmental risks of antibiotics and conservation of aquatic animals. [ABSTRACT FROM AUTHOR]

Frequent outbreaks of harmful cyanobacterial blooms and the microcystins (MCs) they produce seriously affect the survival of aquatic organisms. Interactions between gut microbiota and hosts often play crucial roles in driving the adaptation of aquatic organisms to environmental changes. In this study, we investigated the phenotypic indicators of the freshwater gastropod Bellamya aeruginosa , after uptake of Microcystis aeruginosa and explored its gut microbial composition and gut metabolites in response to toxic cyanobacterial stress. Results showed that the MCs concentration in the hepatopancreas of snails fed with toxic cyanobacteria decreased from 2.64 ± 0.14 μg·g−1 on day 7 to 1.16 ± 0.10 μg·g−1 on day 14. The compositions of the intestinal microbiota of snails fed with different algae significantly differed, and the relative abundance of gut microbes such as Lactobacillus and Sphingobium significantly increased after feeding toxic cyanobacteria. Significant differences also existed in intestinal metabolites, the relative abundance of the following metabolites significantly increased: l -proline, 5,6-DHET, stachyose, raffinose, and 3-isopropylmalate. Sankey network diagrams showing links between gut microbes and gut metabolites. The association of Lactobacillus and Sphingobium with amino acids may be related to host tolerance to toxicity, and the linkages of gut microbes with metabolites such as levan, imidazolepropionic acid, and eicosanoids may be associated with involvement in host immune responses. The association of microbes with stachyose and raffinose can help the host to regulate energy homeostasis. These results reveal the underlying mechanisms of gut microbes in the snail adaptation to toxic cyanobacterial stress. This study could be great important for gaining new insights into toxic cyanobacteria-induced changes in snail gut microbes and metabolites and their roles in snail adaptation to toxic cyanobacterial stress, and may provide important insights into the use of freshwater gastropods for the prevention and control of cyanobacterial blooms. [Display omitted] • Toxic cyanobacteria caused marked changes in gut microbiota and intestinal metabolites in snails. • Snail gut microbes showed comprehensive correlation with significantly changed gut metabolites. • The results revealed the underlying role of gut microbes in snail adaptation to toxic cyanobacteria. [ABSTRACT FROM AUTHOR]

The biotoxicity of heavy metals in sediments toward benthic organisms has evoked great concern for the health of freshwater ecosystems. This study applied a sediment toxicity testing protocol to investigate the single and joint toxicity of cadmium (Cd) and lead (Pb) on Bellamya aeruginosa. B. aeruginosa were exposed to different concentrations of Cd (5, 25, and 100 mg/kg), Pb (20, 100, and 400 mg/kg), and their different concentration combinations. A suite of biomarkers, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), metallothionein (MT), malondialdehyde (MDA), and acetylcholinesterase (AChE), were measured after 7, 14, 21, and 28 days of exposure to evaluate their oxidative stress status. Cell apoptosis of soft tissue was also determined after exposure. Results revealed that these endpoints represented sensitive biomarkers for the characterization of the oxidative stress response induced by these metals. Specifically, a decrease of SOD and GPx and an increase of MDA were indicative of the potential failure of the antioxidant defense system in neutralizing the reactive oxygen species (ROS) generated in the exposure of the Pb-treated group. The integrated biomarker response (IBR) index revealed the most significant sub-lethal toxicity for Pb-spiked sediments, leading to the highest rate of cell apoptosis (70.8%). Exposure to Cd resulted in a time- and dose-dependent effect on MT levels, which suggested active detoxification of this metal. Exposure to the mixture resulted in amelioration of Pb toxicity, likely due to the competitive binding of Cd to active enzyme, with the result of an observed antagonistic interaction. This study indicated that B. aeruginosa represents a good biomonitor for assessing Cd and Pb contamination of sediments, and laid the foundation for their potential risk assessments in freshwater ecosystems. [ABSTRACT FROM AUTHOR]

Effective remediation of heavy metal pollution in aquatic systems is desired in many regions, but it requires integrative assessments of sediments, water, and biota that can serve as robust biomonitors. We assessed the effects of a 5-year metal contamination remediation along the Xiangjiang River, China, by comparing concentrations of trace metals in water and surface sediments between 2010-2011 and 2016. We also explored the trace metal biomonitoring potential of a freshwater gastropod (Bellamya aeruginosa). Metal concentrations in water (means and ranges) dropped over time to within permissible limits of drinking water guidelines set by China, USEPA, and WHO in 2016. Although sediment means and ranges of Cd, Pb, Zn, and Mn also diminished with remediation, those for Cr and Cu slightly increased, and all six metals retained concentrations higher than standards set by China. All metals in sediments could also be associated with anthropogenic inputs using a hierarchical clustering analysis, and they generate high potential ecological risks based on several indices, especially for Cd and As. The bio-sediment accumulation factors of all measured trace metals in gastropod soft tissues and shells were lower than 1.0, except for Ca. Trace metal contents in gastropods were positively correlated with those in water and surface sediments for As (soft tissues) and Cr (shells). Collectively, our results do not yet highlight strong beneficial effects of 5-year remediation and clearly illustrate the heavy metal pollution remaining in Xiangjiang River sediment. Additional physical, chemical, and biological measurements should be implemented to improve sediment quality. We further conclude that gastropod soft tissues and shells can be suitable biomonitors of spatial differences in some heavy metals found within river sediments (e.g., As, Cr). [ABSTRACT FROM AUTHOR]

The contribution of food sources to the freshwater gastropod Bellamya aeruginosa was estimated using stable carbon and nitrogen isotope ratios in three water bodies (two reservoirs and a pond) with different history of cyanobacterial blooms in the eastern part of Zhejiang Province, China. Results of the isotope mixing model showed that filtered food materials (suspended particulate organic matter) contributed most to the diet of B. aeruginosa in both reservoirs with higher levels of chlorophyll a (Chl a) in the water column, except during the summer, when a cyanobacteria (Microcystis) bloom occurred in Reservoir Tingxia. In contrast, scraped food materials (benthic detritus) contributed most to the diet of B. aeruginosa in the pond, where low levels of Chl a were found in the water column. These results suggest that although filtered food materials were the main food source of B. aeruginosa when the habitat was rich in desirable suspended particles, ingestion of filtered food materials decreased during the cyanobacteria bloom. Feeding experiments were conducted to verify whether snails could avoid ingesting the cyanobacteria. The isotopic ratios in muscle tissue of B. aeruginosa fed by a diet containing only cyanobacteria were similar to those of the no-diet treatment, implying that the snails did not feed, when only cyanobacteria were offered. Moreover, the combination of higher mortality, lower fecal pellet counts, and reduced growth (based on shell height) in the treatment with cyanobacteria indicate that B. aeruginosa stopped feeding when food became undesirable, confirming our field observations that B. aeruginosa avoids feeding on toxic cyanobacteria. [ABSTRACT FROM AUTHOR]

The benthic gastropods Bellamya aeruginosa (B. aeruginosa) is ubiquitous in freshwater in China and neighboring countries with great edible value. It has been recognized as a potential manipulator to control harmful algal blooms due to its filtration on algal cells. In this study, the control effect of B. aeruginosa on toxic and non-toxic Microcystis aeruginosa (M. aeruginosa), and the accumulation and depuration of microcystins (MCs) in the snail were systematically explored. Results indicated that although toxic M. aeruginosa could protect itself via producing MCs, the introduction of B. aeruginosa could still effectively inhibit the algae with cell density below 1 × 106 cells/mL. Hepatopancreas was the primary target of MCs in all tissues of B. aeruginosa , presenting a maximum of 3089.60 ng/g DW when exposed to toxic M. aeruginosa of 1.0 × 107 cells/mL. The enrichment of MCs in other tissues following the order of digestive tract > gonad > mantle > muscle. Interestingly, snail could again excrete previously enriched MCs when transferred to non-toxic M. aeruginosa , giving rise to over 80% reduction of MCs in the body. After depuration, the estimated daily intake (EDI) of free MCs in intact individuals and the edible parts of B. aeruginosa were both lower than the tolerable daily intake (TDI). These results implicated that B. aeruginosa could control low density of M. aeruginosa in spring. Particularly, the snail could be perfectly safe to consume by purifying for a while after using as manipulator. [Display omitted] • B. aeruginosa can effectively inhibit M. aeruginosa whose density below 1 × 106 cells/mL. • Toxic M. aeruginosa could protect themselves by releasing microcystins. • B. aeruginosa could renewably excrete microcystins facing with non-toxic algae. • The edible security of B. aeruginosa could be observably improved after depuration. [ABSTRACT FROM AUTHOR]

Objective: To investigate the prevalence of Angiostrongylus cantonensis infection in market-sold and field-captured snails in Fujian Province, so as to provide the scientific basis for the formulation of the angiostrongyliasis control measures., Methods: In each month from May to October during the period from 2017 through 2021, Pomacea snails were collected from two field fixed surveillance sites and Bellamya aeruginosa collected from one agricultural product market in Fuzhou City, while Pomacea and B. aeruginosa snails were collected from two agricultural product markets and four restaurants in Xiamen City. At least 50 Pomacea snails and 500 g B. aeruginosa were sampled each time. A. cantonensis infection was detected in Pomacea snails using lung microscopy, and in B. aeruginosa using a tissue homogenate method., Results: A total of 9 531 Pomacea snails were detected for A. cantonensis infection in two cities of Fuzhou and Xiamen, and the overall prevalence of A. cantonensis infection was 4.40%, with the highest prevalence in 2017 (6.82%, 116/1 701) and the lowest prevalence in 2019 (3.46%, 83/2 400). The prevalence of A. cantonensis infection was significantly higher in Pomacea snails sampled from Fuzhou City (11.23%, 326/2 903) than from Xiamen City (1.40%, 93/6 628) (χ 2 = 461.48, P < 0.01). A. cantonensis larvae were detected in larval Pomacea snails in two cities of Fuzhou and Xiamen each month. The prevalence of A. cantonensis infection in Pomacea snails appeared an overall tendency towards a rise with month in Fuzhou City, with the highest prevalence in October (15.24%), and there was a significant difference among month (χ 2 = 14.56, P < 0.05), while the prevalence of A. cantonensis infection in Pomacea snails was low in Pomacea snails sampled from Xiamen City each month, with the highest prevalence in June (2.64%), and there was a significant difference among month (χ 2 = 23.17, P < 0.05). A total of 18 966 B. aeruginosa snails were detected for A. cantonensis infection in two cities of Fuzhou and Xiamen, and the overall prevalence of A. cantonensis infection was 0.01%., Conclusions: A. cantonensis infection was identified in Pomacea and B. aeruginosa snails in Fujian Province from 2017 to 2021, and there is a potential risk of human A. cantonensis infection.

Various indices based on metal chemical data are used to evaluate pollution and ecological risk, but the consistency of the assessment results is usually unsatisfactory, and it is unclear if the ecological risk from sediment metals is accurately represented in in situ zoobenthos. Herein, the pollution and ecological risk associated with As, Cd, Cr, Cu, Ni, Pb and Zn in the sediments of two adjacent lakes (Datun (DT) and Changqiao (CQ)) were comprehensively evaluated by integrating metal concentrations, chemical forms and bioaccumulation in Bellamya aeruginosa (B. aeruginosa). The metal concentrations and chemical compositions varied widely in the sediments. Over 50% of the Cd, Pb and Zn in the sediments was present in bioavailable forms, followed by 28% of Cu and less than 25% of As, Cr and Ni. According to the enrichment factor (EF) and concentration enrichment ratio (CER) assessments, Cr and Ni were natural in origin, while the other metals were at minor to extremely high pollution levels, with average EFs of 1.5–77.6 and CERs of 1.1–113.4. The pollution levels for Cd, Cu and Pb from the EF and CER assessments were similar, while those for As and Zn were higher according to CER than EF (p = 0.05), likely due to the baseline underestimation associated with the potential diagenetic remobilization of bioavailable metals. The ecological risk index (Er), sediment quality guidelines (SQGs) and risk assessment code (RAC) showed a high eco-risk for Cd, while no similar risk was found for the other metals. By integrating risk indices with the chemical forms and pollution levels of metals, we deduced high eco-risks for As and Pb and moderate eco-risks for Cu and Zn in DT Lake and moderate eco-risks for As, Pb and Zn in CQ Lake. The other metals in the sediments of the two lakes presented low eco-risks. No significant positive correlations (p = 0.05) between metal accumulation in B. aeruginosa and the indices of pollution and eco-risk were observed except for the case of As, implying that measuring the metal concentrations in B. aeruginosa would not accurately characterize the metal pollution and ecological risk of sediments. [Display omitted] • Metal pollution and eco-risk were evaluated by integrating various chemical data and indices. • As, Cd, Cu, Pb and Zn were typical pollutants with minor to extremely high pollution levels. • Discrepancies among the different indices were found in the gradings of metal pollution and ecological risk. • Anthropogenic metal concentrations were comparable between EF and CER assessments. • Bioaccumulation in B. aeruginosa cannot be used to indicate metal pollution and ecological risk in sediments. [ABSTRACT FROM AUTHOR]

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We evaluated the transcriptome dynamics of the freshwater river snail Bellamya aeruginosa exposed to 17β-estradiol (E2) using the Roche/454 GS-FLX platform. In total, 41,869 unigenes, with an average length of 586 bp, representing 36,181 contigs and 5,688 singlets were obtained. Among them, 18.08, 36.85, and 25.47 % matched sequences in the GenBank non-redundant nucleic acid database, non-redundant protein database, and Swiss protein database, respectively. Annotation of the unigenes with gene ontology, and then mapping them to biological pathways, revealed large groups of genes related to growth, development, reproduction, signal transduction, and defense mechanisms. Significant differences were found in gene expression in both liver and testicular tissues between control and E2-exposed organisms. These changes in gene expression will help in understanding the molecular mechanisms of the response to physiological stress in the river snail exposed to estrogen, and will facilitate research into biological processes and underlying physiological adaptations to xenoestrogen exposure in gastropods. [ABSTRACT FROM AUTHOR]

Clarifying the genetic structure can facilitate the understanding of a species evolution history. It is crucial for the management of germplasm resources and providing useful guidance for effective selective breeding. Bellamya is an economically and ecologically important freshwater snail for fish, birds and even humans. Population genetic structures of the Bellamya species, however, were unknown in previous studies. Population genomics approaches with tens to hundreds of thousands of single nucleotide polymorphisms (SNPs) make it possible to detect previously unidentified structures. The population genomic study of seven populations of B. aeruginosa across three river systems (Yellow River, Yangtze River and Pearl River) in China was conducted by SLAF-seq. SLAF-seq obtained a total of 4737 polymorphisms SLAF-tags and 25,999 high-consistency genome-wide SNPs. The population genetic structure showed a clear division among populations from the Yellow River basin (YH and WL) and the Pearl River basin (QSH and LB), as well as population YC from the Yangtze River basin using the SNPs data. However, there existed no distinct population structure using the mitochondrial DNA (mtDNA). The anthropogenic translocation from the Yangtze River basin to the Pearl River basin and the passive dispersion from the Yangtze River basin to the Yellow River basin by flooding have weakened the phylogeographic pattern of B. aeruginosa . The divergence of B. aeruginosa in the three river systems suggests that the anthropogenic dispersal for aquaculture and breeding requires serious consideration of the population structure for the preservation of genetic diversity and effective utilization of germplasm resources.

Benthic invertebrates play important roles in oxygen uptake and nutrient cycling in the benthic boundary layer. Temperature is an important factor that influences both invertebrate activity and the effects of the bioturbation on biogeochemistry. The present study aimed to investigate the influence of temperature on the sediment oxygen uptake and nutrient flux across the sediment-water interface in sediment inhabited by molluscs, animals that often dominate the benthic community. A microcosm was constructed using sediment, lake water, and molluscs from Lake Taihu, China. The clam Corbicula fluminea (Bivalvia: Corbiculidae) and the snail Bellamya aeruginosa (Gastropoda: Viviparidae) were selected for the experiment because they dominate the benthic community in the lake. The effect of C. fluminea and B. aeruginosa on sediment oxygen uptake and nutrient flux was simultaneously examined at both 15 and 25℃. The results indicated that C. fluminea significantly increased the sediment oxygen uptake and release of soluble reactive phosphorus (SRP) and ammonium from the sediment to the overlying water at both temperatures, and the net sediment oxygen uptake, and the net SRP and ammonium fluxes caused by the clams were significantly higher at 25℃ than at 15℃. Moreover, B. aeruginosa significantly increased the sediment oxygen uptake at the two experimental temperatures, however the net sediment oxygen uptake induced by the snail did not differ significantly between 15 and 25℃. The SRP released from the sediment was stimulated significantly by B. aeruginosa at 25℃, and B. aeruginosa also produced significantly more net SRP release at 25℃ than that at 15℃. In contrast, the influence of B. aeruginosa on the net ammonium flux at each temperature was not statistically significant.

The increasingly frequent algal blooms in freshwater have become a major environmental problem in the world. In recent years, algae removal by the biological method is receiving more attention for its eco-friendly characteristics. In this study, we examined the effects of Bellamya aeruginosa , a common macrobenthic snail in eutrophic lakes in China, on the growth and photosynthesis activities of the common algae occurred in freshwater blooms, including cyanobacterium Microcystis aeruginosa , coupled with green algae Chlorella vulgaris and Scenedesmus obliquus . The main aims were to clarify the interactive relationships between B. aeruginosa and algae, and to verify feasibility of using B. aeruginosa as an algal-removing organism. The results showed that B. aeruginosa could feed a large amount of algae cells in a short period after inoculation, and reached the maximal removal rate of toxic and non-toxic M. aeruginosa as well as S. obliquus within 12 hours, which were 73.7%, 73.2%, and 51.1%, respectively. Furthermore, its feeding on C. vulgaris was stronger than on other algae, with the removal rate reaching 99.2% by the end of the experiment. The microcystins produced by the toxic M. aeruginosa accumulated in the body of B. aeruginosa induced the histopathological changes in the liver tissue, and thereby hindered the feeding of B. aeruginosa . In the late stage of the experiment, the photosynthetic activities of the algal cells under each treatment were significantly lower than that in the control, indicating that the feeding of B. aeruginosa damaged algal cells and inhibited their proliferation. In addition, in the mixture of non-toxic M. aeruginosa and S. obliquus , the selective feeding of B. aeruginosa caused the dominance of non-toxic M. aeruginosa to be replaced by S . obliquus . Therefore, B. aeruginosa could inhibit the photosynthesis and reduce the biomass of algae through feeding, and thus would eliminate or mitigate the formation of algal blooms.