Frozen mitochondria as rapid water quality bioassay

Abstract

A rapid and relatively low cost bioassay, usable in routine screening water test has been developed modifying the beef heart mitochondria test. In our experiments, mitochondria (FM22) were frozen at )22°C, instead of )80°C (FM80), and their applicability and sensitivity was verified. The oxygen consumption was measured by a Clark electrode that was interfaced to a PC to collect test analysis data. Blank tests were carried out to verify the oxygen consumption linear fitting. Toxicity tests were performed using pure organic and inorganic compounds, such to verify the FM22 sensitivity. A piecewise regression, through an Excel â Macro, identified the break-point in the oxygen consumption and calculated the toxicity. The IC 50 s of the tested compounds were calculated and ranged from 0.123 to 0.173 mg/l for heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) and from 0.572 to 10.545 mg/l for organics (benzene, DMSO, DDE, endrin, dichloromethane, chlorobenzene, 1,2-dichlorobenzene and 1,3-dichlorobenzene). Water effluent samples were then tested. The FM22 gave different toxic reactions to them. Water samples were characterised for heavy metals. The FM22 bioassay had a higher sensitivity than the FM80 and a high reproducibility in the toxicity test with pure compounds. The FM22 test was a good predictor of toxicity for water samples; the bioassay is easy, low cost and rapid, then usable for routine tests.

An in vitro study of the interaction of sea‐nine® with rat liver mitochondria

“…Studies of the in vitro toxicity of this compound have been performed on fish cells [4] and the viability of the cells has been evaluated using the Alamar Blue dye. It has been demonstrated that, in many cases, the preferential target of the toxic compounds responsible for acute toxicity are mitochondria [5–8]. Therefore, in this study, we used the mitochondria (from rat liver) to study the molecular effects of SN, because the behavior and the molecular structure of mitochondria is similar in all living species.…”

Water Quality Monitoring with the Multiplexed Assay MitoOxTox for Mitochondrial Toxicity, Oxidative Stress Response, and Cytotoxicity in AREc32 Cells

“…Concentration−response relationships for cytotoxicity and MMP disruption were considered for individual chemicals or samples to quantify concentrations causing a 10% effect. The inhibitory concentration for a 10% reduction in cell viability was determined as IC 10 , and the effect concentrations for a 10% reduction of the MMP was determined as EC 10 . In case of oxidative stress, the effect concentration leading to an induction ratio (IR) of 1.5 (EC IR1.5 ) was derived, as described by Escher et al 15 Automated data evaluation was performed using R software (version 4.1.3).…”

“…9 Due to the high environmental relevance of mitochondrial toxicity, it would be desirable to monitor the level of mitochondrial toxicants in environmental mixtures and extracts from biota and blood in biomonitoring studies. There have been attempts to monitor water quality based on oxygen consumption rate as an endpoint for mitochondrial toxicity using isolated mitochondria from bovine heart 10 or HepG2 cells. 11 To date, the quantification of the oxygen consumption rate remains limited to low-throughput systems in the 24-well or 96-well plate format.…”