以原位固相微萃取探討黃豆芽對含氯有機化合物的吸收

Investigation of Absorption of Chlorinated Compounds by Soybean Sprout with in situ Solid Phase Microextraction

陳仕育(Shi-Yu Chen) ； 張美玲(Meei-Ling Chang)

《臺灣農業化學與食品科學》 60卷1期 (2022/03) Pp. 30-36

https://doi.org/10.6578/TJACFS.202203_60(1).0004

摘要

本研究以光纖作為固相微萃取（solid phase microextraction, SPME）纖維，將1 cm光纖直接置入黃豆芽莖部，探討其在農業用有機資材（茶、咖啡、木醋液）配製的培養溶液下對污染物的吸收。光纖經由簡單的預處理，可改善氣相層析的波峰。光纖在各種培養溶液背景下吸收達有龍或1,2,3-三氯苯的檢量線大致良好，惟在達有龍茶水溶液中的線性較不佳，檢量線的靈敏度以純水中最高，顯示有機資材的溶解性成分（dissolved organic matters, DOM）會改變污染物在水、DOM及光纖上的PDMS膜之間的分配。以原位SPME纖維監測水耕豆芽的吸收動力，各培養溶液中的達有龍訊號皆隨時間逐漸下降，12小時後接近平衡。在茶水及咖啡渣培養溶液中，植體汁液中的訊號在初期隨時間增加而升高，之後逐漸平緩；但在木醋培養溶液中，訊號仍持續上升達48小時，推測可能與木醋可促進作物生長有關。對三氯苯的吸收則僅見於以純水培養的黃豆芽，顯示植物對三氯苯的吸收會受DOM所抑制，且吸收濃度也比log K_(ow)值較低的達有龍更低。由原位SPME纖維直接偵測植體汁液中的污染物濃度（C_(pw)），不需使用有機溶劑或耗時的萃取，為一創新及對環境友善的方法，結合組成模式（composition model），可估計植體的總濃度，相信此方法值得應用於食用作物安全性評估與植生復育等領域。

關鍵字

原位固相微萃取 ； 有機資材 ； 達有龍 ； 1,2,3-三氯苯 ； 黃豆芽 ； 組成模式

並列摘要

This study investigates pollutants absorbed through soybean sprouts cultivating in aqueous solutions of agricultural organic materials (tea, coffee, and wood vinegar) by using 1-cm optical fiber with polydimethylsiloxane (PDMS) coating as solid phase microextraction (SPME) fiber, which is embedded in the stem of the soybean sprout during the sorption course. The peak shape of pollutant in GC chromatogram could be improved by the baking pretreatment for the fiber. The sensitivity (slope) of calibration curves for the fiber established from those cultivating solutions were different and less than that in water which suggests that the partition of pollutant among water, dissolved organic matters (DOM), and the coating of fiber would be affected by the DOM. The GC signals of the SPME fibers in the cultivating solutions and the plant were simultaneously monitored during the sorption. Diuron concentration in cultivating solutions gradually decreased and approached to equilibrium in about 12 hr. The signals from in-situ SPME fiber in the plant cultivating in both of tea and coffee solutions gradually increased and then approached to a plateau while that of the plant in wood vinegar continually increased for 48 hr, which may be attributed to the vitality promotion by wood vinegar. However, 1,2,3-trichlorobenzene could only be found in the plant cultivating in water rather than in the organic material solutions. It is suggested that absorption of plant will reduce for pollutant of higher log K_(ow) and be hindered by DOM. In-situ SPME is an innovative and environment friendly method, which can directly and rapidly detect the concentration of plant fluid phase (C_(pw)) without extraction by organic solvent. Once C_(pw) is obtained, then the total absorption amount of plant could be estimated by the composition model. It is believed that the in-situ SPME method is worthy to be applied to evaluation for crop pollution and phytoremediation.

並列關鍵字

in-situ solid phase microextraction ； Organic materials ； Diuron ； 1,2,3-trichlorobenzene ； Soybean sprout ； Composition model

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