Kose A, Oncel S S
Department of Bioengineering, Faculty of Engineering, Ege University, Izmir, Bornova 35100, Turkey.
Biotechnol Rep (Amst). 2015 Feb 21;6:137-143. doi: 10.1016/j.btre.2015.02.005. eCollection 2015 Jun.
SAG 211-12, a green microalga, as model organism was cultivated photomixotrophically using various organic carbon and nitrogen sources at Erlenmeyer scale. The modified medium selected for the experiments was standard BG11 supplemented with 5 g l glucose and 1 g l proteose peptone (PP). To evaluate the effects of light/dark cycles, 12:12; 18:6 and 24:0 light/dark cycle conditions were examined on hourly basis. 24:0 continuous illumination condition was chosen to continue 2 l continuous stirred tank photobioreactor (CSTR) experiments under 1 vvm aeration, 120 rpm mixing time, 23 ± 2 °C, and 70 μE m s illumination conditions. The results showed significant effect of the culture conditions on the cellular composition. To enhance digestibility of the intact cell; dry biomass was digested with pancreatin enzyme solution and protein digestibility (IVPD) of crude biomass (UTS), cell debris (CVA) and protein hydrolysates (CVH) was measured. IVPD values of UTS, CVA and CVH were found to be 33-41%, 46-58%, 67-89%; respectively with no significant changes regarding culture conditions ( > 0,05). Results also showed the positive effect of the enzyme treatment for digestion which is a key advantage for nutritional characteristic of the algal biomass.
绿色微藻SAG 211-12作为模式生物，在锥形瓶规模下利用各种有机碳源和氮源进行光混合营养培养。实验选择的改良培养基是添加了5 g/L葡萄糖和1 g/L蛋白胨（PP）的标准BG11培养基。为了评估光/暗循环的影响，按小时检查了12:12、18:6和24:0的光/暗循环条件。选择24:0连续光照条件，在1 vvm通气、120 rpm混合时间、23±2°C和70 μE m⁻² s⁻¹光照条件下继续进行2 L连续搅拌罐式光生物反应器（CSTR）实验。结果表明培养条件对细胞组成有显著影响。为提高完整细胞的消化率，用胰蛋白酶溶液消化干生物质，并测定粗生物质（UTS）、细胞碎片（CVA）和蛋白质水解产物（CVH）的蛋白质消化率（IVPD）。发现UTS、CVA和CVH的IVPD值分别为33-41%、46-58%、67-89%；培养条件对此无显著变化（P>0.05）。结果还显示了酶处理对消化的积极作用，这是藻类生物质营养特性的一个关键优势。
