Investigation On College Students Lutein Intake In Qingdao And Metabolism Dynamics Research Of Lutein Chitosan Liposomes

Objective: To understand the college students' dietary lutein intake of a university in Qingdao and analyze its influencing factors.Preparation of lutein chitosan liposomes and evaluated its bioavailability in rats.Methods: 1.488 college students were randomly selected from a university in Qingdao to participate in the questionnaire survey.The questionnaire included general condition,eating habits,dietary intake,etc.Investigation by 3 days 24 hours dietary recall survey.To estimate the amount of food with reference to “Atlas of the illustrative food pictures for use in dietary intake recall”,combined the food display and food pictures which purchased from the restaurant and nearby supermarket.Unified training of research object,and a professional investigators on-site guidance.2.Preparation of lutein liposomes by ether injection method and explored the influence of different factors on entrapment efficiency(EE),like concentration of phospholipids,p H value and shearing rate,etc.According to the best optimum condition of preparation of lutein liposomes,modifying it with the suitable concentration of chitosan.3.Male SD rats were randomly divided into the following two groups,lutein oil group and lutein chitosan liposomes group.After gavage,the rats tail vein blood was collected in 1,2,4,6,8,12,16,24 hours respectively.The plasma concentrations of lutein was determined by HPLC.Results: 1.The dietary lutein intake of college students was 2.14 mg/d.Dietary lutein was mainly composed of vegetables.The main dietary lutein sources was leeks,spinach,broccoli,rape,beans and eggs,etc.But what college students daily eat more was potatoes,tomatoes,beans,cabbage,in which the unit lutein content was low.Analysis related factors of college students' dietary lutein,the results showed that body mass index(BMI)too high or too low,dislike vegetables,sleep more than 8h,chronic diseases of the digestive system could decrease college students' lutein intake.Gender,major,appetite,dislike fruit,exercise time impact on college students' lutein intake had no statistical significance(P > 0.05).2.The optimum conditions of lutein liposomes were phospholipids and cholesterol ratio was 5:1,lutein and phospholipids ratio was 1:10,phospholipids concentration was 4%,pH was 6.5,the shearing rate was 12000 revolutions per minute,shearing time was 3 minute.The EE of lutein was 97% and particle size was87 nm.Modified with 0.4% chitosan,its EE was up to 98.26%,particle size was 116 nm.The lutein chitosan liposomes was stable in 4 ? for 30 days.3.Animal experiment results showed that time of maximum concentration(Tmax)of lutein oil and lutein liposomes was 3.8h and 5.7h,and area under the plasma concentration time curve(AUC)was 0.86?g/ml·h and 1.04?g/ml·h,the fraction of bioavailability of lutein chitosan liposomes increased by120.8%?Conclusion: 1.The dietary lutein intake of college students was low.Nutrition education should be strengthened.College students should reasonable diet and proper take food which lutein content is high.2.The lutein chitosan liposomes improved the water solubility,stability and bioavailability in rats of lutein.