There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
In order to reduce the raw material cost of d-lactic acid fermentation, the unpolished
rice from aging paddy was used as major nutrient source in this study. The unpolished
rice saccharificate, wheat bran powder and yeast extract were employed as carbon source,
nitrogen source and growth factors, respectively. Response surface methodology (RSM)
was applied to optimize the dosages of medium compositions. As a result, when the
fermentation was carried out under the optimal conditions for wheat bran powder (29.10g/l)
and yeast extract (2.50g/l), the d-lactic acid yield reached 731.50g/kg unpolished
rice with a volumetric production rate of 1.50g/(lh). In comparison with fresh corn
and polished rice, the d-lactic acid yield increased by 5.79% and 8.71%, and the raw
material cost decreased by 65% and 52%, respectively, when the unpolished rice was
used as a major nutrient source. These results might provide a reference for the industrial
production of d-lactic acid.