Extraction And Content Analysis Of Volatile Constituents In Chinese Jujube

Chinese jujube (Ziziphus jujuba Mill.) belongs to the genus Ziziphus Mill. (Rhamnaceae), is a native fruit tree of China. The chemical compounds isolated from Chinese jujube include cyclic AMP, polysaccharides, dietary fibre, triterpenoids acid, flavonoids, saponins, vitamins, protein and fat, known as "natural health food". Volatile components play an important role in the Chinese jujube fruit quality, however, the study on them fouces on one or two varieties. There is little information of volatile constituents of different organs and the influences of drying on the volatile compounds in Chinese jujube. In this paper, three different methods were used to extract the volatile from jujube fruits, the influences of drying on the volatile compounds of jujube fruits and volatile constituents of different organs of Chinese jujube were also stuied. The results were as follows:1. Three different methods including water steam distillation, solvent extraction and simultaneous distillation extraction were used to extract the volatile from jujube fruits. The results showed that simultaneous distillation extraction could reflect the characteristics volatile better than others methods.2. Twenty-six volatile compounds were identified in three jujube varieties, most of them were acids, aldehydes, esters, hydrocarbons and alcohol. There were differences between different varieties. The major chemical compounds in“Zanhuangdazao”were Z-11-hexadecenoic acid, Z-7-tetradecenoic acid, ethyl 9-hexadecenoate, dodecanoic acid, tetradecanoic acid, (E)-2-hexenal, n-decanoic acid and hexanal.The higher abundances compounds in“Jinsixiaozao”were dodecanoic acid, n-decanoic acid, Z-7-tetradecenoic acid, 2-hexenal, 3-furaldehyde, myristoleic acid, hexanoic acid, hexanal, tetradecanoic acid, ethyl 9-hexadecenoate and dodecanoic acid,ethyl ester. The major chemical compounds in“Dongzao”were Z-11-hexadecenoic acid, Z-7-tetradecenoic acid, dodecanoic acid, tetradecanoic acid, 2-hexenal, furfural, hexanal and n-hexadecanoic acid. Hexanal, dodecanoic acid, Z-7-tetradecenoic acid and tetradecanoic acid were the common main compounds in the three jujube varieties.3. More volatile components were found in jujube fruits after drying, and the content of acids increased. In“Zanhuangdazao”, the content of esters and aldehydes decreased after drying, hydrocarbons, ketones and alcohols were only detected in dried samples. The content of esters, aldehydes, alcohols and hydrocarbons decreased in dried“Jinsixiaozao”, compared with fresh fruits, hydrocarbons, ketones and alcohols were only detected in dried samples. In“Dongzao”, the content of aldehydes decreased after drying, ketones, alcohols, phenols, terpenes and esters were only detected in dried samples.4. It is the first time to detect the volatile compounds in flower buds, flowers, leaves and fruits of three jujube varieties. Hydrocarbons and acids were the main chemical constitutes in flower buds, esters in flower buds of“Zanhuangdazao”and“Dongzao”had a higher content, and in“Jinsixiaozao”alcohols had a higher content. Alcohols, aldehydes and hydrocarbons were the main chemical constitutes in flowers, in“Jinsixiaozao”acids had a higher content. Aldehydes and alcohols were the main chemical constitutes in leaves, phenols in“Zanhuangdazao”had a higher content, hydrocarbons and esters in“Jinsixiaozao”had a higher content, esters in“Dongzao”had a higher content. Acids were the prominent group compounds in jujube fruits.