a The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, JiangNan University , Wuxi , JiangSu Province , P. R. China.
Prep Biochem Biotechnol. 2014;44(4):355-69. doi: 10.1080/10826068.2013.829498.
Industrial waste substrates, sugarcane molasses, and corn steep liquor were used for production of carotenes by Arthrobacter globiformis in this study. At the first stage, a one-factor-at-a-time approach was used for optimization of different media components such as carbon, nitrogen, MgSO(4) · 7H(2)O, and KH(2)PO(4), as well as pH, temperature, liquid medium volume, and inoculums level. The response surface method was further applied to determination of optimum values of process variables for maximum carotenes concentration. Results showed that the optimum combination for carotenes formation was as follows (g/L): sugarcane molasses, 40.00; corn steep liquor, 50.00; MgSO(4) · 7H(2)O, 0.75; KH(2)PO(4), 1.00. The maximum carotene concentration of 1.19 ± 0.02 mg/g dry biomass, about 113% of 1.05 ± 0.02 mg/g dry biomass growing in basal medium, was demonstrated by confirmatory experiments to be the optimum in liquid medium at 100 rpm, 30°C, initial pH of 7.5, and cultivation for 60 hr. In a second stage, detailed studies showed about 1.64-fold and 1.43-fold increase in carotene concentration (mg/g dry biomass) in the presence of addition of ethanol (4%, v/v) and addition of hydrogen peroxide (4%, v/v) at 40 hr, and 32 hr in liquid medium, separately.
在这项研究中，采用球形节杆菌（Arthrobacter globiformis）以工业废基质、甘蔗糖蜜和玉米浆为原料生产类胡萝卜素。在第一阶段，采用单因素法对不同培养基成分（如碳源、氮源、MgSO4·7H2O 和 KH2PO4）以及 pH 值、温度、液体培养基体积和接种量进行优化。进一步采用响应面法确定最大类胡萝卜素浓度的最佳工艺变量值。结果表明，类胡萝卜素形成的最佳组合如下（g/L）：甘蔗糖蜜 40.00；玉米浆 50.00；MgSO4·7H2O 0.75；KH2PO4 1.00。在最佳条件下（100 rpm、30°C、初始 pH 值为 7.5、培养 60 小时），验证实验表明，最大类胡萝卜素浓度为 1.19±0.02mg/g 干生物质，比基础培养基中 1.05±0.02mg/g 干生物质的最大浓度提高了约 113%。在第二阶段的详细研究中，分别在液体培养基中添加 4%（v/v）乙醇和 4%（v/v）过氧化氢，在 40 小时和 32 小时分别使类胡萝卜素浓度（mg/g 干生物质）提高了约 1.64 倍和 1.43 倍。
