Utilization of the zebrafish model to unravel the harmful effects of biomass burning during Amazonian wildfires

Abstract

Amazonian wildfires in 2019 have raised awareness about rainforest burning due to increased emissions of particulate matter and carbon. In the context of these emissions, by-products of lignin thermal degradation (i.e. methoxyphenols) are often neglected. Methoxyphenols entering the atmosphere may form intermediates with currently unknown reaction mechanisms and toxicity. This study for the first time provides a comprehensive insight into the impact of lignin degradation products [guaiacol, catechol], and their nitrated intermediates [4-nitrocatechol, 4,6-dinitroguaiacol, 5-nitroguaiacol] on zebrafish Danio rerio. Results revealed 4-nitrocatechol and catechol as the most toxic, followed by 4,6DNG > 5NG > GUA. The whole-organism bioassay integrated with molecular modeling emphasized the potential of methoxyphenols to inhibit tyrosinase, lipoxygenase, and carbonic anhydrase, consequently altering embryonic development (i.e. affected sensorial, skeletal, and physiological parameters, pigmentation formation failure, and non-hatching of larvae). The whole-organism bioassay integrated with in silico approach confirmed the harmful effects of lignin degradation products and their intermediates on aquatic organisms, emphasizing the need for their evaluation within ecotoxicity studies focused on aquatic compartments.

Bioprospecting of Less-Polar Fractions of Ericaria crinita and Ericaria amentacea: Developmental Toxicity and Antioxidant Activity

“…A zebrafish embryotoxicity test was conducted in accordance with the OECD Test Guideline, with slight modifications already described in Babić et al [56]. The embryos (n = 20, 4-64 blastomeres) were exposed to a wide range of concentrations (FdEa F3 (8-40 µg/L), FdEa F4 (12-194 µg/L), FdEc F3 and FdEc F4 (4-50 µg/L)).…”

The utility of alternative models in particulate matter air pollution toxicology

“…PM immersion studies in zebrafish mimic the natural route of exposure to PM in aquatic organisms that may result from watershed runoff, ash deposits, or other forms of contamination ( Mesquita et al, 2016 , Mesquita et al, 2017 , Babić et al, 2021 ) making it a useful model for screening the ecotoxicological effects of PM and other chemicals. However, PM exposure via immersion and injection contrasts with the primary route of exposure to PM in humans, i.e., inhalation.…”

In Vivo and In Vitro Antioxidant Activity of Less Polar Fractions of Dasycladus vermicularis (Scopoli) Krasser 1898 and the Chemical Composition of Fractions and Macroalga Volatilome

“…Zebrafish maintenance and spawning have been described in our recent paper [43]. The zebrafish embryotoxicity test (OECD 236, 2013) was conducted to determine the negative potential of tested F3 and F4 fractions.…”