Extraction Of Pigment In Fruits Of Ziziphus Jujuba And The Flavonoids Analysis Containing Various Cultivars In Different Regions

From 2009 to 2011, the experiments were carried out by using the fruit of Ziziphus jujuba. The extraction process of pigment, its chemical stability and compositions in fruit, flavonoids analysis containing various cultivars in different regions were studied. The results were summarized bellow:1,The comparing and optimizating pigment extraction process,and innovatively establishing the best extraction process of MWW, the results shew that the proper extraction solvent was 1% NaOH. The optimal hot-water extraction conditions were as follow: water temperature 80℃, solid-liquid ratio 1:25 , extraction time 5.0h. The conditions of ultrasonic-assisted extraction were as follow: extraction power 760W, solid-liquid ratio 1:25, 30min. under 80℃. The optimal conditions of microwave-assisted extraction were as follow: extraction power 640W, 1 min. for the two extraction. The innovative extraction process of MWW conditions were as follow: extraction power 640W, 85℃,1 min., total extraction 3.0h2,The pigment cannot be completely dissolved and easy be precipitation in the acidic environment, the pigment was stable in night,temperature and alkaline conditions, being high solubility with bright color in neutral or alkaline environment, insensitive to light and heat. The pigment was obviously unstable existing Cu²⁺,Al³⁺,Zn²⁺,Mg²⁺, but Na⁺,K⁺,Ca²⁺,Fe³⁺(<35mg/kg)being little influence to the pigment. The pigment was good stability in all kinds of sweeteners and preservatives, but being obviously unstable to the substance of citric acid, ascorbic acid Na₂SO₃ and H₂O₂ .3,Jujube pigment chemical compositions were analyzed by Infrared and GC / MS The results shew that hydrochloric acid-magnesium color reaction and lead salt precipitation test showed the extract contains flavonoids. Infrared spectrum result showed that the pigment structure contains O-H,C-O-C,C-O-H,C-H bond, aromatic ring and heterocyclic ring. The analysis of pigment by GC / MS showing: the main components were glycosides, esters, carboxylic acids and flavonoids; the glycoside substances accounting for 42.48% of total content, esters 22.17% and flavonoids 7.27%, the flavonoids containing quercetin derivatives, catechin, epicatechin and others. the dates may be flavonols were red or flavanol compounds and the results of the combined effects of other substances. The red colour of Ziziphus jujuba may be formated by the flavonols or flavanol compounds with other substances..4,The four kinds of flavonoids analyzed by HPLC in 10 various cultivars in different regions Ziziphus jujube were as follow: The Rutin content was the highest in Jinsixiaozao (Shandong) and was 125.99μg·g^-1,the minimum content was 51.94μg·g^-1 in Tanzao (Shanxi).The Quercetin content was the highest in Hamidaxing (Xinjiang) and was 58.92μg·g^-1, the minimum content was 23.33μg·g^-1 in Banzao (Shanxi). The Chrysin content was the highest in Jinsixiaozao (Shandong) and was 6.00μg·g^-1, the minimum content was 1.70μg·g^-1 in Lingwuchangzao (Ningxia). The Luteolin content was the highest in Hamixiaobaozao (Xinjiang) and was 192.22μg·g^-1, the minimum content was 17.09μg·g^-1 in Banzao (Shanxi).