Comparative Analysis of the Developmental Toxicity in Xenopus laevis and Danio rerio Induced by Al2 O3 Nanoparticle Exposure.

Engineered aluminum oxide nanoparticles (Al2 O3 NPs) having high-grade thermal stability and water-dispersion properties are extensively used in different industries and personal care products. Toxicological response evaluation of these NPs is indispensable in assessing the health risks and exposure limits because of their industrial disposal into the aquatic environment. We assessed and compared the developmental toxicity of Al2 O3 NPs in Xenopus laevis and Danio rerio over a period of 96 h using the frog embryo teratogenic assay Xenopus and a fish embryo toxicity assay. Engineered Al2 O3 NP exposure produced dose-dependent embryonic mortality and decreased the embryo length, indicating a negative effect on growth. Moreover, Al2 O3 NPs induced various malformations, such as small head size, a bent/deformed axis, edema, and gut malformation, dose-dependently and altered the expression of heart- and liver-specific genes in both X. laevis and D. rerio, as revealed by whole-mount in-situ hybridization and reverse transcriptase polymerase chain reaction. In conclusion, the toxicological data suggest that Al2 O3 NPs are developmentally toxic and teratogenic and negatively affect the embryonic development of X. laevis and D. rerio. Our study can serve as a model for the toxicological evaluation of nanomaterial exposure on vertebrate development that is critical to ensure human and environmental safety. Environ Toxicol Chem 2019;38:2672-2681. © 2019 SETAC.

New acylated flavonoid glycosides from flowers of Aerva javanica.

Chromatographic purification of ethyl acetate soluble fraction of the methanolic extract of the flowers of Aerva javanica yielded three new acylated flavone glycosides: kaempferol-3-O-ß-d-[4‴-E-p-coumaroyl-α-l-rhamnosyl(1 â†’ 6)]-galactoside (1), kaempferol-3-O-ß-d-[4‴-E-p-coumaroyl-α-l-rhamnosyl(1 â†’ 6)]-(3″-E-p-coumaroyl)galactoside (2), and kaempferol-3-O-ß-d-[4‴-E-p-coumaroyl-α-l-rhamnosyl(1 â†’ 6)]-(4″-E-p-coumaroyl)galactoside (3), along with p-coumaric acid (4), caffeic acid (5), gallic acid (6), eicosanyl-trans-p-coumarate (7), hexadecyl ferulate (8), and hexacosyl ferulate (9). The compounds 1-9 were characterized using 1D ((1)H, (13)C) and 2D NMR (HMQC, HMBC, and COSY) spectroscopy and mass spectrometry (EI-MS, HR-EI-MS, FAB-MS, and HR-FAB-MS) and in comparison with the reported data in the literature. Compound 1 showed weak inhibitory activity against enzymes, such as acetylcholinesterase, butyrylcholinesterase, and lipoxygenase with IC50 values 205.1, 304.1, and 212.3 µM, respectively, whereas compounds 2 and 3 were only weakly active against the enzyme acetylcholinesterase.