Phytochemical profiles of Citrus hybrid kanpei and Citrus reticulata natsumi : Analysis of volatile and non-volatile components

Abstract

For analyzing the useful components in kanpei and natsumi, volatile as well as non-volatile components were analyzed using HPLC and GC/MS. Kanpei and natsumi juices contain free sugars and organic acids which are involved in imparting sweet and sour flavors. Analysis of the free sugar content revealed that the sucrose content was 6.53±0.31 g/100 g and 7.36±0.28 g/100 g in kanpei and natsumi, respectively. The content of citric acid, which is an organic acid, in kanpei and natsumi was 0.99±0.04 g/100 g and 0.87±0.06 g/100g, respectively. The analysis of 20 different free amino acids revealed that arginine was the most abundant at 65.27 mg/100 g and 38.09 mg/100 g, respectively. Essential amino acids contents were 13.59 mg/100 g and 17.93 mg/100 g, accounting for 5.95% and 14.3% of the total amino acids for kanpei and natsumi, respectively. Narirutin and hesperidin were identified as the major flavonoids in the juice and peel. Furthermore, nobiletin and tangeretin, which are present only in citrus species, were identified in the peels. The analysis of volatile components revealed that kanpei and natsumi had a high content of limonene>γ-terpinene>linalool, while natsumi was characterized by the abundance of limonene>γ-terpinene>β-myrcene. As a result of this study, many functional components were found in large amounts in kanpei and natsumi. This result can be used as cultivar characteristics evaluation.