Hollow Fiber Liquid-Phase Microextraction Combined with Gas Chromatography-Mass Spectrometry for Determination of Root Exudative Potential Allelochemicals in Capsicum Annuum(Chili)

Abstract

Hollow fiber liquid phase microextraction (HF-LPME) was developed for the determination of potential allelochemicals by gas chromatography-mass spectrometry (GC-MS). Biomass method was applied to study the allelopathic effect. The applicability of the proposed procedure was evaluated through extraction of three potential allelochemicals in recirculating hydroponic culture solution of chili. The parameters affecting extraction. The optimum extraction conditions were obtained with 15 µL toluene as acceptor phase at an extraction time, of 30 min, an extraction temperature of 50°C, a stirring rate of 800 rpm, 9% (w/v) sodium chloride, and pH of 6 in a 10 mL sample. The calibration curves showed a high linearity level in the range of 0.1–-5 µg · mL−1, relative standard deviations between 5.51% and 8.94%, and enrichment factors that had 6.3–12.5 were obtained for 2,6-DTBP, DPA, and DIBP. Recoveries, ranging from 81.4% to 118.7% and an RSD below 10.3% were obtained when the method was applied to determine three potential allelochemicals in root exudates of real samples of 10 d, 20 d, and 30 d after cultivation.