Synthesis and Structure Reassignment of Malylglutamate, a Recently Discovered Earthworm Metabolite

Novel spirooxindole alkaloid derivatives from the medicinal insect Blaps japanensis and their biological evaluation

Blapspirooxindoles A-C (1-3), three novel spirooxindole alkaloids with a unique spiro[chromane-4,3'-indoline]-2,2'-dione motif, blapcumaranons A and B (4 and 5), two new 2-cumaranon derivatives, blapoxindoles A-J (6-15), ten new oxindole alkaloid derivatives, along with one known compound (16), were isolated from the whole bodies of Blaps japanensis. Their structures including absolute configurations were determined by using spectroscopic, X-ray crystallographic, and computational methods. Compounds 1-11 and 13 exist as racemic mixtures in nature, and their (-)- and (+)-antipodes were separated by chiral HPLC. Biological evaluations of these compounds were determined with multiple assays including anti-tumor, anti-inflammatory, and renal protection activities in vitro. Several compounds displayed effective activity in one or more assays.

Metabolite biomarkers of chlorothalonil exposure in earthworms, coelomic fluid, and coelomocytes

Earthworm (Eisenia fetida) metabolomics is a useful indicator of toxicant exposure. Extracts of whole earthworms are most commonly used to measure metabolic perturbations, in addition to coelomic fluid which has been used on a more limited basis. Coelomocytes are free moving cells found within earthworm coelomic fluid, and the potential of this compartment has not been evaluated for its utility in earthworm metabolomics. In this study, earthworms were exposed to 18.5 and 37.0 mg/kg chlorothalonil, a commonly used fungicide that targets glutathione. The metabolic impacts of a 14-day chlorothalonil exposure were assessed using ¹H NMR and targeted LC-MS measurements of earthworm, coelomic fluid, and coelomocyte extracts. Coelomic fluid was identified as the most sensitive matrix for measuring the effects of chlorothalonil exposure, where an increase in glutamine levels was the only biomarker observed at both doses. At the high dose, multiblocked-orthogonal partial least squares-discriminant analysis (MB-OPLS-DA) supported increased N-acetylserine and ophthalmic acid levels as additional biomarkers of exposure in coelomic fluid. These perturbations may indicate increased oxidative stress, although no changes in glutathione were observed in any matrix.