Study On The Screening Of Candida Strains And Preparation Of Metallothionein

Metallothionein referred to as MT, is a widely present in vivo (except birds), cysteine-rich low molecular weight metal-binding proteins. Strong free radical scavenging, anti-aging, anti-cancer effects, has high research value. The experimental production Nguyen Candida yeast strains by physical mutagenesis and chemical mutagenesis has been the production of a high yield of metallothionein Nguyen Candida strains. And through the single factor experiment to optimize the fermentation conditions of the strains and strains extraction process is optimized by orthogonal experiment. Finally radical scavenging function and Vc to verify The optimum fermentation conditions and optimal extraction conditions on the strains experimental Cu-MT has strong free radical scavenging ability. Data base and theoretical support for the industrial production of yeast production metallothionein.The experiment eventually get a yield metallothionein strain N’’-6production metallothionein than starting sulfhydryl activity of strains reached0.062. Sulfhydryl activity than the starting time of0.013compared to4.77times. The strain after five passages training, little change in the indicators, you can determine its genetic stability.In the second experiment mutant N"-6strains produce metallothionein fermentation process for single-factor experiments, from the eight factors were explored, looking to the second chapter of the resulting strain N"-6The more The fermentation conditions were:activation of the strain40h after induction medium containing1.2mmol/L CuCl2, as an inducer induced at30℃40h shaking speed set at200r/min, inoculum size lml/50ml, The inducing medium liquid loading is set to50m1/250ml conical flask.In Experiment3, the extraction process of metallothionein orthogonal experiment results show that select the pH8.6Tris-HCI buffer between the dry cell solid-liquid ratio (g:mL)1:12ultrasonic The extraction time was20min, the ultrasonic extraction intensity of350W, and80°C heat denaturation time taken6min. According to the experimental results of the orthogonal experiment, strain N"-6through the the Chapter proceeds optimized fermentation process, and the fourth chapter proceeds optimum extraction process to obtain class metallothionein. Detect its sulfhydryl activity assay was0.098, compared to before optimization the mercapto activity increased1.58times.Experiment IV verified this experiment proceeds metallothionein strong scavenging of free radicals. The comparison indicates that the experiment proceeds metallothionein radical scavenging about Vc of3.03times stronger than Vc. The proof of this experiment, the use of high-yielding metallothionein utilis yeast N"-6, obtained metallothionein activity can provide a basis for industrial production strains...