Contents of three kinds of multi-methoxy flavonoids and aroma components in tangerine peel oils from different origins

In this study，the contents of three individual polymethoxylated flavonoids（nobiletin，sevenmethoxy flavonoids，tangeretin）and the aroma components were compared and analyzed in the tangerine peel oils from Guangxi，Guangdong Xinhui，Guangzhou suburbs，Jiangxi and Hunan，to provide evidence for the selection of tangerine peel and the origin identification. The results of the determination of polymethoxylated flavonoids showed that the contents of three individual polymathoxylated flavonoids in tangerine peel oils from the five different origins varied significantly，the tangerine peel from Guangxi ranked the highest，with the total of 33.401 mg/mL，followed by the tangerine peel oils from Guangdong Xinhui，Jiangxi and Guangzhou suburbans，which were 19.091，18.058 and 16.710 mg/mL respectively；and the total contents of the three individual polymethoxylated flavonoids from Hunan origin Tangerine peel was the lowest with 8.705 mg/mL. The GC/MS results showed that tangerine peel oil from Guangdong Xinhui contained 41 constituents，with the main component of olefine，alkane and also a small amount of aldehyde， alcohols，vitamin E，sinensetin and so on，which was far richer than other 4 tangerine peel oils，whose constituents were mainly alkene substances（such as D- limonene etc.）. These substances accounted for above 95% of the total tangerine peel oil component.