Chlamydomonas reinhardtii is one of the most characterized green algae. The open-pond cultivation can be challenging due to sensitivity of strain to fluctuating environmental conditions and unavailability of low-cost photoautotrophic media. In this study, the photoautotrophic growth of C. reinhardtii was evaluated in 1-m2 open ponds placed in greenhouse. Sodium bicarbonate (NaHCO3) was evaluated as an alternative buffering agent to tris. The effect of buffer and pH was tested. The growth was studied in the presence of various nitrogen [urea and ammonium bicarbonate (NH4HCO3)] sources. In the study, it was found that 125-ppm NaHCO3 as an optimum concentration. The buffering agent in the media was found to have major impact on growth. Without buffering agent, culture did not grow, and pH drop was observed. The sodium bicarbonate-buffered media reported to have the lowest bacterial contamination (18.3%), highest AFDW per OD (0.39 ± 0.027 g/L) and higher Fv/Fm (0.714 ± 0.016), whereas these values were found to be 62%, 0.19 ± 0.02 g/L and 0.537 ± 0.053 for tris-grown culture, respectively. The pH 7.0-7.5 was determined as an optimum, whereas pH 6.5-7.0 and 8.0-8.5 were found to affect the growth and induce palmelloidy. The OD and AFDW of culture grown in NH4HCO3 were found equivalent to a standard nitrogen source (NH4Cl), whereas culture shown poor growth in urea. Based on these data, NH4HCO3 media recipe and the optimized cultivation parameters were selected for photoautotrophic cultivation of Chlamydomonas in greenhouse open ponds.

中文翻译：

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温室露天池塘莱茵衣藻光自养培养

莱茵衣藻是最具特征的绿藻之一。由于菌株对波动的环境条件的敏感性和低成本光能自养培养基的不可用，露天池塘培养可能具有挑战性。在这项研究中，莱茵衣藻的光合自养生长在温室中的 1 平方米开放池塘中进行了评估。碳酸氢钠 (NaHCO3) 被评估为 Tris 的替代缓冲剂。测试了缓冲液和 pH 值的影响。在各种氮[尿素和碳酸氢铵 (NH4HCO3)] 源存在下研究了生长。在研究中，发现 125 ppm NaHCO3 作为最佳浓度。发现培养基中的缓冲剂对生长有重大影响。在没有缓冲剂的情况下，培养物不生长，并且观察到 pH 值下降。据报道，碳酸氢钠缓冲介质具有最低的细菌污染 (18.3%)、最高的 AFDW/OD (0.39 ± 0.027 g/L) 和更高的 Fv/Fm (0.714 ± 0.016)，而这些值被发现为 62% , 0.19 ± 0.02 g/L 和 0.537 ± 0.053 对于 tris 生长的培养物。pH 7.0-7.5 被确定为最适，而 pH 6.5-7.0 和 8.0-8.5 被发现影响生长并诱导棕榈状。发现在 NH4HCO3 中培养的培养物的 OD 和 AFDW 相当于标准氮源 (NH4Cl)，而培养物在尿素中的生长较差。基于这些数据，选择了NH4HCO3培养基配方和优化的培养参数，用于温室开放池塘中衣藻光合自养培养。714 ± 0.016)，而对于 Tris 培养的培养物，发现这些值分别为 62%、0.19 ± 0.02 g/L 和 0.537 ± 0.053。pH 7.0-7.5 被确定为最适，而 pH 6.5-7.0 和 8.0-8.5 被发现影响生长并诱导棕榈状。发现在 NH4HCO3 中培养的培养物的 OD 和 AFDW 相当于标准氮源 (NH4Cl)，而培养物在尿素中的生长较差。基于这些数据，选择了NH4HCO3培养基配方和优化的培养参数，用于温室开放池塘中衣藻光合自养培养。714 ± 0.016)，而对于 Tris 培养的培养物，发现这些值分别为 62%、0.19 ± 0.02 g/L 和 0.537 ± 0.053。pH 7.0-7.5 被确定为最适，而 pH 6.5-7.0 和 8.0-8.5 被发现影响生长并诱导棕榈状。发现在 NH4HCO3 中培养的培养物的 OD 和 AFDW 相当于标准氮源 (NH4Cl)，而培养物在尿素中的生长较差。基于这些数据，选择了NH4HCO3培养基配方和优化的培养参数，用于温室开放池塘中衣藻光合自养培养。发现在 NH4HCO3 中培养的培养物的 OD 和 AFDW 相当于标准氮源 (NH4Cl)，而培养物在尿素中的生长较差。基于这些数据，选择了NH4HCO3培养基配方和优化的培养参数，用于温室开放池塘中衣藻光合自养培养。发现在 NH4HCO3 中培养的培养物的 OD 和 AFDW 相当于标准氮源 (NH4Cl)，而培养物在尿素中的生长较差。基于这些数据，选择了NH4HCO3培养基配方和优化的培养参数，用于温室开放池塘中衣藻光合自养培养。