Shikonin In Lithospermum Extraction And Functional Study

The main research topics of this task as the following five aspects.First,the studay of Lithospermum pigment's extraction process in Lithospermum. Comparison of advantages and disadvantages of the two methods:alkaline extraction and acid precipitation method and alcohol extraction method. And through orthogonal test to determine the best conditions for extraction. Second,using of Thin Layer Chromatography, identify the components of Lithospermum extract.Useing Ultraviolet and Visible Spectrophotometry, scaning in the 190nm～600nm wavelength range, analysed the major components of extract. Functional groups was determined by infrared analysis. By comparing the mass spectra of extractive and L-shikonin sample, identifying the main components.Third,the study of crude extract's oxidation resistance. It would be embodied through the inhibition rate of Lithospermum extract on pyrogallol autoxidation and axunge oxidation.Forth,the study of crude extract's antimicrobial. The bacteriostasic activity to Staphylococcus aureus,Bacillus subtilis,Bacillus coli,beery microzyme, penicillium,Rhizopus and Mucos of Lithospermum extract.Fifthly,the application of Lithospermum extract in strawberry's refreshment.Eventually the technic has been identified as the microwave-assisted extraction method of alcohol extraction. This method can obtained high purity extracts. And the color and gloss of the crude extracts is far better than the method of alkaline extraction and acid-derived extracts. The process conditions follow as:W:V=1:10, the power of micro-wave is 640 W, the time of micro-wave is 5min,the vol. concentration of alcohol is 70%, in a water bath of 80℃,constant temperature reflux extraction 60min.Through Thin Layer Chromatography, Ultraviolet and Visible Spectrophotometry,Infrared Analysis and FHR,we learned that the main components of Lithospermum extract is shikonin. Lithospermum extract has excellent antioxidant and antibacterial effects. And it can well be applied to fresh strawberries.Shikonin belonging to naphthoquinones compounds,not only have strong anti-oxidation, but also for the temperature and the air have a good stability. But the application of Lithospermum in food only Shikonin as fruit juices, beverages, ice cream, popsicles, fruit coloring agent used. This has been clearly defined in GB2760-1996. The antioxygenation of Lithospermum has been research,but hasn't used in food production as anti-oxidant and preservative. Manufacturer always add the chemical using the method of anti-oxidants and preservatives to extend shelf-life of food products. However, chemical additives runs counter to people's pursuit of green fashion. Food additives market is moving in the direction of natural extracts.The natively and safty of Lithospermum extract bring its wide developmental foreground.Task offer theoretic basis and technical support for Lithospermum's application in food industry;broaden the train of thought for natural extracts' application in food.