School of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
Environ Sci Technol. 2010 Aug 15;44(16):6364-70. doi: 10.1021/es1002499.
The dominant bacteria in nonphotosynthetic microbial community (NPMC) isolated from the ocean were identified by PCR-DGGE. The results revealed that the dominant microorganisms in cultures of NPMC differed when Na(2)S, Na(2)S(2)O(3), and NaNO(2) were used as the electron donor to reduce CO(2). These findings implied that different microorganisms in the NPMC respond to different inorganic compound as suitable electron donor, indicating that matching of Na(2)S, Na(2)S(2)O(3), and NaNO(2) may provide mixed electron donors that increase the ability of NPMC to fix CO(2). Accordingly, the central composite response surface method (RSM) was used to predict the optimal concentration and match of Na(2)S, Na(2)S(2)O(3), and NaNO(2) as mixed electron donors to improve CO(2) fixation efficiency under aerobic and anaerobic conditions without hydrogen. The results indicated that 0.46% NaNO(2), 0.50% Na(2)S(2)O(3), and 1.25% Na(2)S were the optimal match under aerobic conditions, while 1.04% NaNO(2), 1.07% Na(2)S(2)O(3), and 0.98% Na(2)S were the optimal match under anaerobic conditions. Under these conditions, the fixed CO(2) by NPMC was determined to be 387.51 and 512.57 mg/L, respectively, which obviously exceeded those values obtained prior to optimization (5.94 and 7.14 mg/L, respectively), as well as that obtained when hydrogen was used as the electron donor (91.60 mg/L).
从海洋中分离出的非光合微生物群落（NPMC）中的优势细菌通过 PCR-DGGE 进行了鉴定。结果表明，当使用 Na(2)S、Na(2)S(2)O(3)和 NaNO(2)作为电子供体还原 CO(2)时，NPMC 培养物中的优势微生物不同。这些发现表明，NPMC 中的不同微生物对不同的无机化合物作为合适的电子供体有不同的响应，这表明 Na(2)S、Na(2)S(2)O(3)和 NaNO(2)的匹配可能提供混合电子供体，从而提高 NPMC 固定 CO(2)的能力。因此，采用中心复合响应面法（RSM）预测了 Na(2)S、Na(2)S(2)O(3)和 NaNO(2)作为混合电子供体的最佳浓度和匹配，以提高有氧和无氧条件下无氢时 CO(2)固定效率。结果表明，有氧条件下的最佳匹配为 0.46% NaNO(2)、0.50% Na(2)S(2)O(3)和 1.25% Na(2)S，而无氧条件下的最佳匹配为 1.04% NaNO(2)、1.07% Na(2)S(2)O(3)和 0.98% Na(2)S。在这些条件下，NPMC 固定的 CO(2)分别为 387.51 和 512.57mg/L，明显高于优化前的值（分别为 5.94 和 7.14mg/L），也高于使用氢气作为电子供体时的值（91.60mg/L）。
