Yu Changjiang, Sun Changjiang, Yu Li, Zhu Ming, Xu Hua, Zhao Jinshan, Ma Yubin, Zhou Gongke
Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, PR China.
Beijing Risun Chemical Industry Technology Research institute Co. Ltd, Beijing, 100070, China.
PLoS One. 2014 Dec 17;9(12):e115023. doi: 10.1371/journal.pone.0115023. eCollection 2014.
Energy crises and environmental pollution have caused considerable concerns; duckweed is considered to be a promising new energy plant that may relieve such problems. Lemna aequinoctialis strain 6000, which has a fast growth rate and the ability to accumulate high levels of starch was grown in both Schenk & Hildebrandt medium (SH) and in sewage water (SW). The maximum growth rates reached 10.0 g DW m(-2) day(-1) and 4.3 g DW m(-2) day(-1), respectively, for the SH and SW cultures, while the starch content reached 39% (w/w) and 34% (w/w). The nitrogen and phosphorus removal rate reached 80% (SH) and 90% (SW) during cultivation, and heavy metal ions assimilation was observed. About 95% (w/w) of glucose was released from duckweed biomass hydrolysates, and then fermented by Angel yeast with ethanol yield of 0.19 g g(-1) (SH) and 0.17 g g(-1) (SW). The amylose/amylopectin ratios of the cultures changed as starch content increased, from 0.252 to 0.155 (SH) and from 0.252 to 0.174 (SW). Lemna aequinoctialis strain 6000 could be considered as valuable feedstock for bioethanol production and water resources purification.
能源危机和环境污染已引发了广泛关注；浮萍被认为是一种有潜力的新能源植物，有望缓解此类问题。在 Schenk & Hildebrandt 培养基（SH）和污水（SW）中培养了生长速度快且能积累大量淀粉的浮萍品系 6000。SH 培养基和污水培养的浮萍，其最大生长速率分别达到 10.0 g DW m(-2) day(-1) 和 4.3 g DW m(-2) day(-1)，而淀粉含量分别达到 39%（w/w）和 34%（w/w）。培养过程中氮和磷的去除率分别达到 80%（SH）和 90%（SW），并且观察到了重金属离子的同化作用。浮萍生物质水解产物中约 95%（w/w）的葡萄糖被释放出来，然后由安琪酵母发酵，乙醇产量分别为 0.19 g g(-1)（SH）和 0.17 g g(-1)（SW）。随着淀粉含量的增加，培养物的直链淀粉/支链淀粉比例发生变化，从 0.252 变为 0.155（SH），从 0.252 变为 0.174（SW）。浮萍品系 6000 可被视为生物乙醇生产和水资源净化的宝贵原料。
