Department of Chemistry and Chemical Engineering, MOE Engineering Research Center of Forestry Biomass Materials and Bioenergy, Beijing Forestry University, Beijing, 100083, China.
College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
Carbohydr Polym. 2018 Nov 15;200:122-127. doi: 10.1016/j.carbpol.2018.07.063. Epub 2018 Jul 20.
Waste paper has considerable potential as a raw material for lactic acid (LA) production due to high cellulose content, abundance and low cost. In this study, four kinds of waste papers were used for LA production through simultaneous saccharification and fermentation (SSF) by Streptococcus thermophilus. The SSF of office paper achieved the highest LA concentration (39.71 g/L), while the highest LA yield was observed for magazine (99.56%), followed by office paper (82.85%). High LA concentration is unfavorable to total LA conversion because of product inhibition. However, the addition of Gleditsia saponin (GS) could obtain both high yield and high concentration of LA at a low enzyme loading, indicating that product inhibition could be moderated. A lactic acid yield of 86.30% was obtained from office paper at an enzyme loading of 9 FPU/g-cellulose with GS, which was higher than that of without GS at a higher loading of 18 FPU/g-cellulose.
废纸由于其纤维素含量高、丰富、成本低，具有相当大的作为生产乳酸（LA）原料的潜力。在这项研究中，通过嗜热链球菌的同步糖化发酵（SSF），使用四种废纸生产 LA。办公用纸的 SSF 达到了最高的 LA 浓度（39.71g/L），而杂志的 LA 产率最高（99.56%），其次是办公用纸（82.85%）。由于产物抑制，高 LA 浓度不利于总 LA 转化率。然而，添加皂角苷（GS）可以在低酶用量下获得高 LA 浓度和高产量，表明产物抑制可以得到缓解。在 GS 存在下，用 9 FPU/g-纤维素的酶用量从办公用纸中获得了 86.30%的乳酸产率，高于在更高的 18 FPU/g-纤维素酶用量下没有 GS 的产率。
