WTV2.0:A high-coverage plant volatilomics method with a comprehensive selective ion monitoring acquisition mode

Volatilomics is essential for understanding the biological functions and fragrance contributions of plant volatiles.However,the annotation coverage achieved using current untargeted and widely targeted volatomics(WTV)methods has been limited by low sensitivity and/or low acquisition coverage.Here,we introduce WTV 2.0,which enabled the construction of a high-coverage library containing 2111 plant volatiles,and report the development of a comprehensive selective ion monitoring(cSIM)acquisition method,including the selection of characteristic qualitative ions with the minimal ion number for each compound and an optimized segmentation method,that can acquire the smallest but sufficient number of ions for most plant volatiles,as well as the automatic qualitative and semi-quantitative analysis of cSIM data.Importantly,the library and acquisition method we developed can be self-expanded by incorporating compounds not present in the library,utilizing the obtained cSIM data.We showed that WTV 2.0 increases the median signal-to-noise ratio by 7.6-fold compared with the untargeted method,doubled the annotation coverage compared with the untargeted and WTV 1.0 methods in tomato fruit,and led to the discovery of menthofuran as a novel flavor compound in passion fruit.WTV 2.0 is a Python library with a user-friendly interface and is applicable to profiling of volatiles and primary metabolites in any species.

溶剂红135染料中六氯苯含量的测定

Determination of hexachlorobenzene (HCB) in the solvent red 135 by solvent extraction GC-MS with selected ion monitoring mode.The result showed that the detection limit is 0.05 mg/kg.The relative standard deviation is 3.3%.This method is suitable for the analysis of the HCB in the solvent red 135.

Determination of hyperoside in rat plasma after intravenous administration by UPLC-MS

Hyperoside is one of the major components of Hypericum perforatum L. and also present in many plant species such as Abelmoschus manihot （L.） Medik., Ribes nigrum L. and Rosa agrestis Savi （Rosaceae）. Because hyperoside exhibits many biological activities, the pharmacokinetics profile of hyperoside needs to be studied for further elucidating its mechanism of action. A simple method for the determination of hyperoside in rat plasma was developed by using ultra-high performance liquid chromatography coupled with mass spectrometry （UPLC-MS）. Only 50 ~tL plasma samples were required for sample preparation. The quantitative detection of hyperoside was accomplished by selected ion monitoring （SIM） in negative ion mode. Hyperoside was analyzed in less than 10 rain. Good linearity was obtained （r2〉0.999） and the intra- and inter-day precision of the method were lower than 15%. Lower limit of quantification （LLOQ） was 4 ng/mL for hyperoside in rat plasma. Our method showed advantage in the lower LLOQ compared with the reported method; furthermore, smaller amount of plasma was needed. The method was successfully applied for the pharmacokinetics study of hyperoside in rat after intravenous administration of hyperoside.