The extraction and detection of limonene (4-Isoprophenyl-L-Methyl Cyclohexene) from citrus peel using headspace solid phase micro-extraction (HS - SPME) and gas chromatography with mass spectrometry (GC-MS) / Nur Husna Zainal Abidin

Waste citrus peels can be used as source of several bioactive compounds. Among these, limonene is the major constituent from citrus peels and is of great interest in several fields. In this study, the analysis of volatile compounds in four citrus peel samples, specifically limonene, was carried out using headspace solid - phase microextraction and gas chromatography - mass spectrometry detector to detect and relatively quantify the amount of limonene in all of the citrus peel samples. The conditions of SPME were optimized. The optimized extraction temperature, extraction time and desorption time were 70 °C, 40 min and 100 sec respectively. The retention time (tR.) for limonene in this study was 11.70 min. It was found that limonene was detected in all four citrus peel samples. Kaffir lime peel has the highest peak area of limonene which was 8.23 x 109 while key lime peel has the lowest peak area of limonene which was 3.24 x 109.