Volatile components from Exocarpium Citri Grandis (ECG) were, respectively, extracted by three methods, that is, steam distillation (SD), headspace solid-phase microextraction (HS-SPME), and solvent extraction (SE). A total of 81 compounds were identified by gas chromatography-mass spectrometry including 77 (SD), 56 (HS-SPME), and 48 (SE) compounds, respectively. Despite of the extraction method, terpenes (39.98~57.81%) were the main volatile components of ECG, mainly germacrene-D, limonene, 2,6,8,10,14-hexadecapentaene, 2,6,11,15-tetramethyl-, (E,E,E)-, and trans-caryophyllene. Comparison was made among the three methods in terms of extraction profile and property. SD relatively gave an entire profile of volatile in ECG by long-time extraction; SE enabled the analysis of low volatility and high molecular weight compounds but lost some volatiles components; HS-SPME generated satisfactory extraction efficiency and gave similar results to those of SD at analytical level when consuming less sample amount, shorter extraction time, and simpler procedure. Although SD and SE were treated as traditionally preparative extractive techniques for volatiles in both small batches and large scale, HS-SPME coupled with GC/MS could be useful and appropriative for the rapid extraction and qualitative analysis of volatile components from medicinal plants at analytical level. 1. Introduction Exocarpium Citri Grandis (ECG, Huajuhong in Chinese), the dried unripe or ripe fruit peel of Citrus grandis Osbeck or Citrus grandis Osbeck var. tomentosa Hort, is a well-known traditional Chinese medicine [1]. Since it has been proved to possess the effects of clearing heat and expectoration, regulating the flow of vital energy, and stimulating appetite, ECG has been employed in the treatment of coughing, dyspepsia, nausea, itching of throat, and so forth, which makes it widely used in practice for a long time in China [2–4]. ECG from Citrus grandis “tomentosa” (Maojuhong in Chinese) is generally acknowledged to be of better quality than Citrus grandis (L.) Osbeck (Guangjuhong in Chinese). ECG from Huazhou city, Guangdong province, whose plant origin is Citrus grandis “tomentosa,” is usually considered as the genuine medicinal materials [5]. Main phytochemical constituents of ECG were reported as volatile oil, flavonoids, coumarins, and polysaccharides [6–8], among which volatile composition has been investigated worldwide and the essential oil from ECG was broadly used as aroma flavor in food products and flavoring agents to mask the unpleasant tastes of drugs in pharmaceutical
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