In this work, sugar cane juice was fermented to produce polyhydroxyalkanoates (PHAs) by Alcaligenes latus TISTR 1403 and A. eutrophus TISTR 1095. The juice was characterized and composed of total sugars 105.5 g·...In this work, sugar cane juice was fermented to produce polyhydroxyalkanoates (PHAs) by Alcaligenes latus TISTR 1403 and A. eutrophus TISTR 1095. The juice was characterized and composed of total sugars 105.5 g·L^-1 (sucrose 36.6g·L^-1 , fructose 26.0g·L^-1 , glucose 21.8g·L^-1 and other sugars 21.1g·L^-1 ). Each inoculums ( 10%, v/v) was separately cultivated in the medium containing 20g·L^-1 total sugars under condition (30℃, 200 rpm, pH 6.5-7). It was found that the A. eutrophus can be grown better than the A. latus. Only the A. eutrophus was further cultured under different total sugar concentrations (20, 30, 40 and 50g·L^-1 ). The optimal contents of total sugar, dry cell mass (DCM) and maximum PHAs were obtained at 50g·L^-1 , 6.013g·L^-1 and 1.84g·L^-1 , respectively after 60 h fermentation which were converted to biomass yield (Yx/s), product yield (Yp/5), specific product yield (Yp/x) and productivity of 0.163, 0.05, 0.306 and 0.031 g.Llhl. Large scale of PHAs production was conducted in 5 L fermentor using the optimal condition obtained under 30% dissolved oxygen. The DCM and the maximum PHAs were 5.881g·L^-1 and 1.281g·L^-1 which were calculated to values of Yx/s, Yp/s, Yp/x and productivity at 0.19, 0.04, 0.218 and 0.021g·L^-1 , respectively.展开更多
文摘In this work, sugar cane juice was fermented to produce polyhydroxyalkanoates (PHAs) by Alcaligenes latus TISTR 1403 and A. eutrophus TISTR 1095. The juice was characterized and composed of total sugars 105.5 g·L^-1 (sucrose 36.6g·L^-1 , fructose 26.0g·L^-1 , glucose 21.8g·L^-1 and other sugars 21.1g·L^-1 ). Each inoculums ( 10%, v/v) was separately cultivated in the medium containing 20g·L^-1 total sugars under condition (30℃, 200 rpm, pH 6.5-7). It was found that the A. eutrophus can be grown better than the A. latus. Only the A. eutrophus was further cultured under different total sugar concentrations (20, 30, 40 and 50g·L^-1 ). The optimal contents of total sugar, dry cell mass (DCM) and maximum PHAs were obtained at 50g·L^-1 , 6.013g·L^-1 and 1.84g·L^-1 , respectively after 60 h fermentation which were converted to biomass yield (Yx/s), product yield (Yp/5), specific product yield (Yp/x) and productivity of 0.163, 0.05, 0.306 and 0.031 g.Llhl. Large scale of PHAs production was conducted in 5 L fermentor using the optimal condition obtained under 30% dissolved oxygen. The DCM and the maximum PHAs were 5.881g·L^-1 and 1.281g·L^-1 which were calculated to values of Yx/s, Yp/s, Yp/x and productivity at 0.19, 0.04, 0.218 and 0.021g·L^-1 , respectively.