Preparation And Properties Of "N-Butanol-Water-Tea Oil-Saponin" Microemulsion System

Camellia oleifera is the largest woody oil tree species in China.The oil tea cake remaining after oil extraction has a very rich yield every year,and it is still rich in various natural active ingredients such as tea oil and tea saponin.And the abandonment of camellia cakes can cause huge waste of resources.At present,there are still defects in the processing technology of oil tea cakes,such as complicated process,time-consuming labor and large investment.Even though many researchers have greatly improved the extraction rate of products,there are still shortcomings such as single target products and high energy consumption.In the early stage,the research team used the wet grinding technology of n-butanol aqueous solution to extract tea oil and tea saponin from the oil tea cake,which overcomes the defects of the processing technology of the existing oil tea cake.Based on this,the paper analyzes the system of n-butanol-water-tea oil-saponin.Through the construction and analysis of the system,the microscopic changes of the system in the process of simultaneous extraction of tea oil and saponin by n-butanol aqueous solution were explored.And screening the best preparation process,providing a theoretical basis for the efficient extraction of tea oil and saponin.The main findings are as follows:1.Analyzing the particle size of the clear and transparent “n-butanol-water-tea oil-saponin” system(water content 15%),the average particle size of the droplets is 57.00 nm,and the polydispersity index PDI is 0.200,same as the characteristics of microemulsion.Thus,the "n-butanol-water-tea oil-saponin" four components can form a microemulsion system.The addition of tea saponin increases the amount of water-n-butanol system dissolved in tea oil.When the ratio of tea saponin to n-butanol is 1/140,the water-n-butanol system dissolves the maximum amount of tea oil.2.By measuring the conductivity,the prepared "n-butanol-water-tea oil-saponin" microemulsion system is a W/O type microemulsion.The change of pH has no significant effect on the formation ability of "n-butanol-water-tea oil-saponin" microemulsion system;When the "n-butanol-water-tea oil-saponin" microemulsion is prepared by using sodium acetate solution,sodium chloride solution,potassium chloride solution,sodium hexametaphosphate solution and sodium citrate solution,The order of formation ability of the microemulsion system is: sodium hexametaphosphate> anhydrous sodium acetate> sodium citrate> sodium chloride> potassium chloride;When the "n-butanol-water-tea oil-saponin" microemulsion system is prepared with a concentration of 0.000,0.050,0.075,0.100,1.000,2.000 mol/L of NaCl solution,the formation ability of the microemulsion system first increases and then reduce.When the NaCl concentration is 0.05 mol/L,the microemulsion formation ability can be improved to the utmost extent;When the "n-butanol-water-tea oil-saponin" microemulsion system is prepared with a concentration of 0%,5%,10%,15%,20% glucose solution,the microemulsion is higher with the concentration of the glucose solution.The stronger the formation ability.3.Select the three factors of temperature,Km value and S/O value,and design the three-factor and three-level response surface test with the emulsion efficiency as the index,Optimize the preparation process of “n-butanol-water-tea oil-saponin” microemulsion system.The preparation process was optimized to obtain the optimum preparation conditions: the temperature was 76.73°C,the 1/Km value was 161.64,and the S/O value was 9.41:1.4.The stability of the "n-butanol-water-tea oil-saponin" microemulsion sample prepared under the optimal process conditions was evaluated.It was found that the centrifugation,temperature and storage time had no significant effect on the stability of the system.The salt concentration has a significant effect on the stability of the microemulsion system.When the NaCl solid added in the system forms a NaCl solution with a concentration of 1.0 mol/L in the aqueous phase of the system,the system exhibits obvious demulsification and stratification occurred after standing.5.Combine the content of tea oil and tea saponin in tea cake,determine the extraction conditions,set the ratio of material to liquid to 1:1.20 at 77 °C,and use an aqueous solution of n-butanol with a water content of 23.43%.Simultaneous extraction of tea oil and tea saponin from cold pressed tea cake,the tea oil extraction rate was(93.61±1.67)%,and the tea saponin extraction rate was(56.28±1.21)%,which had superior extraction efficiency.