overview_bact_biolum.xlsx

A battery of four bioassays was exposed to the POCIS extracts to determine environmental mixture toxicity at the four sites (Table 1). Before application in the bioassays, the POCIS extracts were evaporated under a gentle stream of N₂ to dryness and reconstituted in dimethyl sulfoxide (DMSO). An in vivo bacterial bioluminescence inhibition assay using Alliivibrio fischeri was performed at the Vrije Universiteit Amsterdam following Hamers et al. (2001) to assess bacterial luminescence inhibition (commercially known as the Microtox® assay). Dose-response curves for the in vivo assays were made in GraphPad Prism (GraphPad Software Inc., version 9.1.2.226, San Diego, CA, USA) and the half maximal effective concentration (EC₅₀), expressed as the relative enrichment factor of the extract in the bioassays, was determined by non-linear regression with a built-in log-logistic model. Toxicity was expressed in toxic units (TU) and was calculated by 1/EC₅₀.