China
Africa
Explore chapters and articles related to this topic
Current Issues and Challenges of Applying Microalgae in Environmental Biotechnology
Published in Pau Loke Show, Wai Siong Chai, Tau Chuan Ling, Microalgae for Environmental Biotechnology, 2023
Xiao Gui Xing, Gao Ya Qian, Sook Sin Chan, Guo Rui Xin, Kit Wayne Chew, Pau Loke Show
Some algae (e.g. Microcystis aeruginosa) have microcystins (Schreidah et al. 2020), these toxins pose a significant threat to ecosystems and drinking water quality, which are not suitable for environmental monitoring or environmental treatment. Therefore, the nature of algae species used in environmental biotechnology is also required to be considered. In addition, for some pollutants with low environmental concentration, their impact on algae may not be observed in a short time. For example, Zhang et al. (2017) showed that the growth of microalgae was not affected after 96 hours of exposure to plastic debris. The conclusion that a chemical is non-toxic cannot be drawn only based on the fact that a chemical has no toxic effect on algae. The long-term impact of chemicals on the ecological environment cannot be ignored. It is time-consuming to observe the long-term toxicity of low-concentration pollutants only by prolonging the exposure time. On the other hand, there may be unpredictable problems in the process. Considering that some adverse effects of pollution can only be seen in the environmental after a long time, algae with higher sensitivity than the existing algae may be developed to study the environmental risks of those low-concentration chemicals. Although bioassay is useful in assessing the toxicity of chemicals, there are still some limitations, including, for example, when assessing the impact of pollutants and chemicals, different results may be obtained due to highly specific experimental conditions – that is the repeatability of experiments is limited (Müller et al. 2016).
Toxicity Reduction of Microcystis Aeruginosa Using Microbubble Ozonation
Published in Ozone: Science & Engineering, 2023
Gwiwoong Nam, Min-Seo Jeon, Yoon-E Choi, Jinho Jung
Cyanobacterial blooms are frequently reported in rivers and lakes especially in summer, which produce toxic metabolites that affect both aquatic organisms and human beings (Bullerjahn et al. 2016; Huisman et al. 2018; Paerl and Huisman 2009). Microcystis aeruginosa is one of the most serious and common harmful cyanobacteria (Su et al. 2018; Wang, Chen, Xie, Shang, Ma 2016; Wang and Bai 2017), mainly due to the production of toxins, such as microcystins (MCs) (Chen, Chen, Zhang, Xie 2016; Saraf et al. 2018; Smutná et al. 2014). Several studies reported that M. aeruginosa has acute (mortality) and chronic (growth inhibition and reduced number of offsprings) adverse effects on aquatic organisms (Smutná et al. 2014; Dao, Do-Hong, Wiegand 2010;Shahmohamadloo, Poirier, Almirall, Bhavsar, Sibley 2020). In Lürling (2003a, 2003b) demonstrated that M. aeruginosa (1 × 106 cell mL−1) significantly suppressed development and growth of Daphnia magna and eventually decreased their population growth rate. Considering that daphnids may not distinguish between toxic and nontoxic Microcystis (Shahmohamadloo, Simmons, Sibley 2020), they are substantially vulnerable to toxic cyanobacteria including M. aeruginosa.
Environmental applications of ultrasound activated persulfate/peroxymonosulfate oxidation process in combination with other activating agents
Published in Critical Reviews in Environmental Science and Technology, 2023
Swapnil K. Gujar, G. Divyapriya, Parag R. Gogate, P. V. Nidheesh
Apart from bacteria, cyanobacterial blooms (Microcystis aeruginosa) in aquatic environment cause a severe threat to human health and environment since they can produce carcinogenic hepatotoxins. Wu et al. (2019) studied the inactivation of Microcystis aeruginosa under the catalyst-mediated US-assisted activation of PMS. The uniformly distributed Fe3O4 nanoparticles on the carbon matrix of MWCNTs catalyst exhibited higher removal (90.6% in 30 min) with the catalyst load of 5 mg L−1 and an US frequency of 800 kHz. Similar to bacteria, the inactivation of Microcystis aeruginosa begins with the cell wall penetration of radical species leading to the intracellular damage and consequently cell death occurs.