کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1208170 1493741 2007 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Analysis of free and conjugated phytosterols in tobacco by an improved method using gas chromatography–flame ionization detection
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی آنالیزی یا شیمی تجزیه
پیش نمایش صفحه اول مقاله
Analysis of free and conjugated phytosterols in tobacco by an improved method using gas chromatography–flame ionization detection
چکیده انگلیسی

An improved and simple method using capillary gas chromatography coupled with a flame ionization detection system (GC–FID) has been developed for quantitative analysis of free and conjugated phytosterols in tobacco. Direct acid and alkaline hydrolysis were first introduced into tobacco analysis to liberate free phytosterols from conjugates, followed by extraction with hexane, derivatization to trimethylsilyl ether derivatives and finally GC quantitative determination. The generality and applicability of this improved method for analyzing free and conjugated phytosterols in tobacco were validated after a series of optimization and comparison were done. Compared with traditional methods, this improved method not only simplified procedures, but also saved time and solvent. The limits of detection (LODs) of phytosterols varied from 0.35 to 0.10 μg mL−1, the relative standard deviations (RSD) were from 2.3% to 3.3% and recovery ranged from 87% to 99%. The analysis results showed that total phytosterols’ content in tobacco ranged from 1.0 to 2.5 mg g−1, and most phytosterols existed as conjugates, only approximately 15–25% phytosterols existed in free-form. Ergosterol was only found in mildewy flued-cured tobacco and the level was approximately 0.2–0.25 mg g−1.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Chromatography A - Volume 1163, Issues 1–2, 7 September 2007, Pages 304–311
نویسندگان
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