Fermentation Production Of Sophorolipid From Rice Straw And Its Application Research

As a sort of novel natural biological surfactant,sophorolipids(SLs)were concerned by many fields extremely on account of its' s high interfacial activities(embellish,moistureproof,etc.)and good biological activities(anti-tumor,anti-inflammatory,anti-bacterial,etc.).Especially in pharmaceutical industry,there were great theoretical research value and application potential.However,SLs research was still in the laboratory stage because of high productio n cost,complex composition,low added value application and etc.limiting factors.To reduce the production cost and broden the of application fields of pharmaceutical SLs,the main research co ntents were as follows,which will establish foundation for the SLs industrialization.1.Rice straw hydrolysate with the pretreatment of ?SO3 micro-explosion? was taken as hydrophilic carbon source,which is a direct replacement for glucose.The effects of inoculum dose and yeast extract(YE)content etc.conditions on SLs fermentation were optimized.The results shows that SLs yield was increased at the early stage and then decreased with dose,the highest production of SLs was 53.70 g/L when the inoculum dose and YE content were 2 % and 0.15 % respectively.2.The conclusion that there is a negative correlation(y=50.93-8.032x)between the broth p H and the lactonic SL yield,also there is a negative correlation(y=112.5-17.14x)between the broth p H and the ratio of lactonic SL/total SL were proposed firstly.And relationships will still hold when different pH controllers were used to adjust fermentation pH.The conclusion laid a theoretical foundation for SLs application,also the SLs production and the utilization efficiency of raw material were improved.3.Based on the solvent extraction separation of SLs process,according to the difference of desity and state characteristic between acidic SL and lactonic SL,sedimentation-alcohol method was proposed with high separation efficiency.Besides,it will decrese the amount of extraction solvent,reduce the risk of industrialization production,reduce the production cost,and more suitable for the large-scale application.4.According to the SLs' s structure and functional properties,tobacco shred was fistly taken as experimental subject,and the moisturizing properties were evaluated in different additive amount.