Reserch On The Selection And Application Of Strains With Lipase Production And Camellia Saponin Tolerance

The isolation, selection, acclimatization, optimation, and identification of strains that yield lipase were studied in this thesis. The isolated strains were fermented with the optimal conditions in the extracting solution of camellia seeds cake in order to remove the oil residue for better utilization of the solution. The main aspects studied in this paper are as follows:1. Isolation, Selection, Taming, and Identification of Lipase-producing StrainsAfter the isolated strains were purified on the nutrient agar, the test was employed to find out if the isolated strains produced lipase. The stains were cultivated and tamed in the nutrient agar with a series of the concentrations of camellia seed oil extracting solution. Based on the measures of camellia saponin before and after the fermentation, those strains which did not decompose camellia saponin were identified.By testing the degrading rate of oil residual in the solution with the Nuclear Magnetic Resonance Oil Content Analyser, one strain was obtained and named Strain K. The morphological characteristics, colonial morphology and physiology, and biochemistry test of Strain K indicated that Strain K belonged to Candida rugosa.2. Optimization of the Lipase-Producing Strain Ultraviolet mutagenesis of protoplast was done to optimize the production of lipase. The cultural conditions were as follows:80minutes for the enzymolysis time,35℃as culture temperature, and14hours for the mid-logarithmic growth phase of the bacteria. The time of getting better UV irradiation was10minutes.3.Optimation of the Conditions for Removing Oil ResidueThe factors, such as fermenting time and temperature, inoculating concentration, and shaking speed, have impact on the removal of the oil residue in the extracting solution of camellia seeds cake. To optimize the consitions, these factors were chosen for the response surface experiment. The optimal conditions were:fermenting8days, under34℃with12%inoculating concentration at130r/min of shaking speed.4.Comprehensive Utilization TestThe optimized strain was utilized to ferment the liquid from the process of extracting camellia seed oil with the aqueous-enzymatic technology to decrease the content of carbohydrate, protein, and fat in the liquid. The fermented liquid was used as the raw material for extracting camellia saponin or as silk and wool detergent. With this way, it will not only reduce the pollution to aquatic animals and plants from the discharged waste water, but also increase revenue by recycling the liquid from the process of extracting camellia seed oil with the aqueous-enzymatic technology. It paved the way for the aqueous-enzymatic technology of extracting camellia seed oil from laboratory into industrialization.