Analysis Of Jujube Flowers Aroma Components And Main Chemical Components

Jujubae is the fruit of Ziziphus jujuba Mill belonging to the Rhamnaceae family. Jujube is mainly distributed in the tropical and subtropical region in Asia and North America. It blooms in May and flowers for three months. However, few information have been reported in jujube flower. Our study was based on the jujuba flower collected from the science arboretum of Agricultural University of Hebei. The pretreatment process of GC-MS analysis for jujuba flower was optimized. A preliminary analysis about the aroma prifiles of flower which from nine Varieties(fengmiguan、jingzao、yueguang、suanzao17、suanzao11、xingtai608、zanyou、zi1、xingtai0648), nutrient component and mineral element of different varieties were determined respectively. The extraction conditions of polysaccharide were optimized and the polysaccharide was isolated and purified further to analysis its composition.The best treatment parameters for GC-MS analysis of flower aroma is:2g sample in the headspace bottle, keeping 60 min at 40℃ water bath and headspace direct injection method was used. By analysis of the database retrieval and the spectrum chart of the system,60 and 59 aroma components were found from nine varieties jujuba flowers and four organs of fengmiguan using GC-MS. The presented compounds in different samples were mainly esters, alkane, aldehyde, ketones. It is included pterin-6-carboxylic acid、nonaldehyde、2- methyl butyrate、4-cyclopropyl carbonyl oxy tridecane、ethyl benzoate、9,12,15-octadecatrienoic aldehyde、á-ocimene、E-2- benzoic acid vinyl ester、ethyl ester of ethyl cinnamon、cyclopropane tetradecanoic acid 2-butyl methyl ester、1,4-benzenedicarboxylic acid methyl ester and so onAnalysis result of chemical components of nine varieties jujuba flowers is as follow: Moisture content between 74.89%-77.23%; protein content between 0.91%-0.96%; fat content in 0.24%-0.26%; crude fiber content between 1.76%-1.96%; total ash content in 1.41%-1.50%, mineral elements including Ca(2023~2384μg/g)、Fe(99.36~133μg/g) Mg(59.2~69.6μg/g)、 Zn(8.2 ~9.9μg/g). The results show that the chemical composition in 9 varieties of jujube flowers had no obvious difference.Polysaccharide was extracted by ethanol precipitation method. A serious of single factor tests(the solvent ratio, ultrasonic time, extraction temperature and time) and response surface methodology was introduced to optimized the extraction conditions. It concluded that the optimum extracting conditions for polysaccharide were: the solvent ratio: 1:45、ultrasonic time: 13min、extraction temperature: 100℃. Polysaccharide extraction rate is 18.57mg/g of fresh flowers,which consistent with the expectations. After dialysis and derivative with PMP, polysaccharide crude extract was used for analysis monosaccharide constitute by HPLC. The results showed that it was mainly composed of mannose, rhamnose, galactose, glucose xylose, arabinose with the mass ratio of 2.00:1.00:1.00:0.41:0.62:1.00.