Biosynthesis of Polyhydroxybutyrate from Giant Reed Grass Hydrolysate and Evaluation of its Drug Releasing Profiles

摘要

The cost of biopolymer production is one of the most important factor restricting the industrial application of Polyhydroxybutyrate (PHB). The main aim of this present study is to explore suitable low-cost novel substrate for PHB production. In this study, giant reed grass (GRG) biomass was pretreated with different concentration of NaOH (1-3%) at various conditions like room temperature, microwave irradiation high temperature and pressure (HTP). Among these three conditions, at the HTP pretreatment with 2% NaOH, the maximum fermentable glucose of 79.32% was obtained after removal of llignin by SC/AA treatment. Further, this pretreatment condition was used for hydrolysate preparation for PHB biosynthesis using B. subtilis RNM. Under optimized condition, the maximum PHB of 46.21±0.2 gLsup-1 /supwas obtained from GRG hydrolysate. This result indicates that the GRG hydrolysate could be a novel low-cost substrate for PHB biosynthesis. This is the first attempt we made to use GRG hydrolysate as feedstock for PHB biosynthesis. Moreover, the produced PHB was characterized by sup1/supH NMR, FTIR and thermal amalysis (DSC and TGA) techniques. The characterized results were very similar to characters of commercial PHB. Further, the produced PHB was used for doxorubicin - PHB microparticles preparation with 93.21±0.15 % of encapsulation efficiency and found its anticancer drug delivery efficiency as 98%. Hence, this study demonstrates that the PHB biosynthesized from GRG hydrolysate could be a best biodegradable polymer for anticancer drug doxorubicin encapsulation and delivery.