Microcapsules Technology And Optimization Research For Controlled Release Salidroside

Salidroside possesses antihypoxia, antifatigue, antimicrowave radiation and antipoison. It can adjust nervous system and endocrine system and have an effect of antiaging, cardiovascular system diseases resistant, antitumor and the aged diseases. The health products presently developed have some drawback, such as rise and fall of drug body concentration, low utilization ratio, frequently eating. So it is important for enhancing function of antihypoxia, antifatigue, antimicrowave radiation and antipoison to study chitosan-sodium alginate microcapsules for salidroside controlled release. It can improve biological utilization ratio, extend period of validity, reduce eating frequency.Firstly, the technological process conditions for microwave assisted extraction (MAE) was studied. Then alginate-chitosan controlled-release salidroside microcapsules were prepared and the neural network model has been established. Finally, the optimum process parameters were obtained by using genetic algorithm.MAE needs simple instrument and can be used for the extraction of various compounds, with characteristics of high efficiency and selectivity, good repetition, less pollution and saving time, solvents and energy. So salidroside was extracted by water as solvent from Rhodiola with MAE. According to analyzing mechanism of MAE and factors influencing extraction, the key factors, including the ration of solid to liquid, soak time, microwave power, microwave irradiation time, stirring extraction period and stages of extraction, were selected and studied for the extraction yield. The optimized technological process conditions were the ration solid to liquid 1:20, soaking for 1.5 h, low grade microwave power, irradiation by microwave for 60 s, stirring extraction period 15 min and the stages of extraction 2. The optimal extraction yield of salidroside from rhodiola was 90 %.Chitosan and alginate, which possess health function and a good nonimmunogenicity. They are enzymatically degradable, poisonousless, inexpensive and easily in film and finished form. The electrostatic interaction of alginate with chitosan,whose reaction are mild, forms a membrane of encapsulation. These semi-permeable membranes are fit for encapsulation of biological active substance. So chitosan and alginate, ideal encapsulation materials for water-soluble substance in food industry, have a growing and promising field for functional compounds microcapsules. Controlled release of salidroside from chitosan-alginate microcapsules was studied. The method was selected on the basis of property of salidroside and emulsification experments. The effect of process parameters, such as alginate concentration, ratio of alginate weight to salidroside weight, chitosan concentration, reaction time and chitosan solution pH value, on drug loading, encapsulation rations and release property of alginate-chitosan microcapsules was studied. The results indicated that when alginate concentration was below 2.5 %, drug loading and encapsulation ration gradually increased and release property of alginate-chitosan microcapsules was gradually slowed with its increasing. But when it was beyond 2.5 %, the results was contrary ï¼›Drug loading gradually decreased , encapsulation ration gradually increased and release property of alginate-chitosan microcapsules was gradually slowed with the ratio of alginate weight to salidroside weight increasingï¼› Release property of alginate-chitosan microcapsules was gradually slowed , encapsulation ration gradually increased with chitosan concentration increasing, but when it was beyond 0.8 %, drug loading decreased ï¼› Drug loading and encapsulation ration increased with CaCI concentration increasing, release property became bad when CaCI concentration went to extremesï¼›Drug loading and encapsulation ration gradually decreased as the forming time was extended, the forming time had no effect on release propertyï¼›When chitosan solution pH value was below 5.5,drug loading and encapsulation ration gradually increased and release property of alginate-chitos...