Determination and Safety Assessment of Residual Spirotetramat and Its Metabolites in Amaranth (Amaranthus tricolor) and Soil by Liquid Chromatography Triple-Quadrupole Tandem Mass Spectrometry.

With the purpose of guaranteeing the safe use of spirotetramat and preventing its potential health threats to consumers, a QuEChERS extraction method coupled with LC triple-quadrupole tandem MS was applied in this study to determine residual spirotetramat metabolites in different tissues of amaranth (Amaranthus tricolor) and in soil. The results indicate that the spirotetramat degraded into different types of metabolites that were located in different tissues of amaranth and in soil. B-keto, B-glu, and B-enol were the three most representative degradation products in the leaf of amaranth, and B-glu and B-enol were the two major degradation products found in the stem of amaranth; however, only B-enol was detected in the root of amaranth. B-keto and B-mono were the two products detected in the soil in which the amaranth grew. The cytotoxicity results demonstrate that spirotetramat and its metabolite B-enol inhibited cellular growth, and the toxicity of spirotetramat and its metabolite B-enol exceeded than that of the metabolites B-keto, B-mono, and B-glu. This investigation is of great significance to the safe use of spirotetramat in agriculture.

Assessment of the genotoxic and mutagenic properties of Himatanthus articulatus bark extracts used as phytotherapeutic drug in the Amazon.

ETHNOPHARMACOLOGICAL RELEVANCE: Himatanthus articulatus (Apocynaceae) is a plant native to the Amazon, popularly used to treat external ulcers, tumors, inflammations, cancer, syphilis and malaria. AIM OF THE STUDY: To investigate the in vivo genotoxic and mutagenic potential of this plant, using the comet assay and the micronucleus test. MATERIAL AND METHODS: Female and male adult mice were treated with 500 mg/kg, 1000 mg/kg or 2000 mg/kg of Himatanthus articulatus aqueous or ethanolic bark extracts by gavage for two consecutive days. In addition, blood slides were exposed to hydrogen peroxide (ex vivo) to evaluate the anticlastogenic effect using the comet assay. The HPLC analyses indicated plumieride as the main constituent of both extracts from Himatanthus articulatus barks. RESULTS: No differences between genders were observed. Micronuclei were observed only in the group treated with the highest dose of both extracts. Conversely, lower doses of these extracts showed protective effects to DNA against damage induced by hydrogen peroxide, indicating an important antigenotoxic effect. CONCLUSIONS: The toxicological evaluation indicated that the extracts are non-genotoxic and reduce the clastogenic damage induced by hydrogen peroxide. In part, this result can be atributted to the phytochemical profile of Himatanthus articulatus, which presents iridoids and phenolic compounds.

From retrospective assessment to prospective decisions in natural product isolation: HPLC-SPE-NMR analysis of Carthamus oxyacantha.

An extract of Carthamus oxyacantha (wild safflower) was investigated using two approaches: a traditional, nontarget fractionation by VLC and HPLC, and the hyphenated technique HPLC-PDA-HRMS-SPE-NMR followed by targeted isolation of selected constituents for inclusion in a screening library of pure natural products. While the nontarget fractionation involved considerable time spent on pursuing fractions containing well-known or undesired compounds, the hyphenated analysis was considerably faster and required less solvent and other consumables. The results were used to design and execute an optimized, HPLC-HRMS-guided, targeted isolation scheme aiming exclusively at a series of identified spiro compounds. Thus, HPLC-PDA-HRMS-SPE-NMR is a dereplication technique of choice, allowing economical acquisition of comprehensive data about compounds in crude extracts, which can be used for rational, prospective decisions about further isolation efforts. A total of 15 compounds were identified in the extract. Six spiro compounds, of which four have not previously been characterized, and tracheloside (a lignin glucoside) are presented with assigned 1H and 13C chemical shifts.