LAUSR

Alligator weed (Alternanthera philoxeroides) is a stoloniferous, amphibious and perennial herb which has invaded many parts of the world and led to serious environmental and ecological problems. In order to exploit cheap carbon source for poly (3-hydroxybutyrate) (PHB) production, alligator weed hydrolysates were prepared by acid and enzyme treatment and used for PHB production via Cupriavidus nector. The bacterium utilized alligator weed enzymatic hydrolysate and produced the PHB concentration of 3.8 ± 0.2 gL-1 at the conditions of pH 7.0, 27.5 °C, 1.5 gL-1 of nitrogen source, and 25 gL-1 of carbon source, this exceeded the value of 2.1 ± 0.1 gL-1 from acid hydrolysate media at the same conditions. In order to obtain the optimum conditions of PHB production, response surface methodology was employed which improved PHB content. The optimum conditions for PHB production are as follows: carbon source, 34 gL-1 ; nitrogen source, 2 gL-1 ; pH, 7; temperature, 28 °C. After 72 h of incubation, the bacterium produced 8.5 gL-1 of dry cell weight and 4.8 gL-1 of PHB. The PHB was subjected to Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and Molecular weight analysis and found the melting temperature, number average molecular mass and polydispersity were 168.20 °C, 185 kDa and 2.1 respectively. This article is protected by copyright. All rights reserved.