| The quality of Mingguang mung bean as the crown of the country, known as "Ming mung bean", once seen as a tribute. Its crystal color green, big grain thin, rotten soup Qingyi, fragrance delicious and other characteristics. In 2008, it was listed as "national geographical indication protection products". The research on Ming mung bean have focused on planting for a long time in our country, but its basic characteristics, functional characteristics, comprehensive utilization and depth development of mostly lack of depth systematic study. At the same time, the achievement of using high and new technology to the raw material for the depth development is still rare.In this paper, Ming mung bean as the raw material, the basic components were determined; the isolation and purification of phenylalanine ammonia-lyase?PAL? in Ming mung bean was studied by saturation of ammonium sulfate grade deposition, dialysis desalting, DE-52 anion exchange chromatography. Studying on the properties of PAL preliminarily, and the influence of external factors such as metal ions and amino acids on the activity of the enzyme. The separation and purification of superoxidase dismutase?SOD? was studied by the adoption of saturated ammonium sulfate fractional precipitation,dialysis desalting, Sephadex G-75 molecular sieve chromatography.The Plackett-Burman design and response surface method was used to optimize ultrasonic assisted extraction SOD from Ming mung bean. At the same time, the preparation of SOD liposome?L-SOD? was optimized by response surface method.Studying on the properties of SOD and the stability of liposome encapsulated SOD preliminarily. It provided a theoretical basis for the comprehensive utilization of Ming mung bean and its further development and utilization of functional ingredients. The main results were as follows:1. The basic components of mung bean were as follows:?1? The content of basic component in Ming mung bean: water 11.82%, crude starch53.25%, crude protein 25.26%, crude fat 0.90%, ash content is 3.70%;?2? The content of essential amino acid in the Ming mung bean: valine 22.57 mg/g,threonine 16.63 mg/g, methionine, 5.94 mg/g, isoleucine 18.21 mg/g, leucine, 38.00 mg/g,phenylalanine 28.50 mg/g, lysine 35.23 mg/g; Threonine is the first limiting amino acid in Ming mung bean;?3? The content of mineral in Ming mung bean: Ca 47.76, Cu mg/kg 0.54 mg/kg, Fe 1.94mg/kg, Zn 2.09 mg/kg, mg/kg 576.69 K, Mn 0.79 mg/kg;2. The best conditions for the separation and purification for PAL from Ming mung bean:PAL eluent p H value of 8.8, best ionic strength is 0.4 mol/L sodium chloride. PAL purification multiples of 6.982 9, protein yield was 4.65%, the enzyme yield is 32.45%.3. The basic characteristics of PAL in Ming mung bean :?1? The suitable p H range of PAL in borax and boric acid buffer solution is 7.6 7.6, the optimum p H was 8.0 and 8.6.?2? The optimum temperature range of PAL between 35 45 ?, the optimum reaction temperature is 40 ?.?3? There are two Km about PAL, respectively: Km1 6.94 x 10-5mol/L, Km2 of 1.23 x10-4 mol/L. The molecular weight of the subunit was 52 KD and 57 KD, respectively, by SDS-PAGE identification.?4? L-cysteine, histidine and tyrosine ferulic acid has inhibitory effect on PAL activity, the degree of inhibition with inhibitors differ. L-tyrosine inhibitory effect is stronger, is a competitive inhibitor to PAL. L-cystine had no effect on the activity of PAL.4. The best extraction conditions of SOD from Ming mung bean : The optimal extraction conditions for SOD were determined as phosphate buffer at p H 7 as the extraction solvent with a solvent-to-solid ratio of 22:1?m L/g?, water bath extraction at 44 ? with an ultrasonic power of 140 W for 20 min and subsequently at 60 ? for additional 1.5 h without ultrasonication. Under these conditions, the specific activity of SOD was 856.95U/mg.5. The separation and purification of SOD from Ming mung bean: SOD purification multiples of 29.93, protein yield was 4.65%, the enzyme yield is 46.62%.6. The basic properties of SOD in Ming mung bean :The SOD has certain stability to acid,the optimum p H range for 6 8; The SOD has some thermal stability, the optimum temperature range for 40 60 ?, the optimal temperature of 60 ?.The SOD is Cu/Zn-SOD.7. The best preparation process parameters of SOD liposome: optimal phosphatidylcholine/cholesterol mass ratio, lipid concentration, the ratio of oil phase to aqueous phase were2.1:1, 21 mg/L and 4.1:1. Under these conditions, the encapsulation efficiency of SOD liposomes is 88.71%.8. Stability of encapsulated L-SOD: the cumulative release is 12 h, the release of SOD degree is 77%, the release of SOD degree is 95% when its' time to 24 h. At 80 ? water bath temperature for 150 min, L-SOD relative energy is 90%, the free of SOD is only 2%.By pepsin function after 10 min at 37 ?, the free residual SOD activity 5.2%, L-SOD activity of the residual 72.6%. |
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