Laboratoire de Chimie Bioorganique et Organique Physique-UA CNRS 456, Ecole Nationale Supérieure de Chimie de Paris 11, rue P. et M. Curie, 75231 Paris Cedex 05, France.
Biotechnol Bioeng. 1989 Sep;34(6):755-62. doi: 10.1002/bit.260340605.
Various water-immiscible solvents were tested for biocompatibility and hydrocarbon recovery under different contact conditions with the hydrocarbon-rich microalga Botryococcus braunii. Eighteen solvents were first selected from a database of 1500 compounds (compiled for solvent selection for ethanol recovery from Saccharomyces cerevisiae fermentation). Nine of these candidate solvents were shown to be biocompatible with B. braunii following short contact times. This biocompatibility tends to be associated with high molecular weights and high boiling points but strongly depends on solvent chemical structure. A low polarity is essential to biocompatibility and calculated octanol-water partition coefficients, or capacity factors determined by reversed-phase high-performance liquid chromatography (HPLC), are suitable predictors of biocompatibility with B. braunii. High recoveries of hydrocarbons directly from the algal culture require relatively polar solvents and are, therefore, inimical with maintenance of cell viability. The inaccessibility of weakly polar solvents to the cell surface appears to protect the algae but also prevents substantial recovery of the hydrocarbons stored in B. braunii outer walls. In order to achieve a high recovery, contact with the solvent must be carried out on algae concentrated by filtration. Then, a large fraction of B. braunii hydrocarbons can be recovered, after a short contact time, without impairing cell viability. Under these conditions, the pertinent solvent property is affinity for the nonpolar hydrocarbons, and the highest recovery yield, approximately 70% after contact for 30 min, is achieved with hexane.
研究了 18 种与富含碳氢化合物的微藻 Botryococcus braunii 在不同接触条件下具有生物相容性的疏水性溶剂，这些溶剂均来自数据库中的 1500 种化合物（为从酿酒酵母发酵中回收乙醇而选择溶剂时编译）。结果发现，在短时间接触后，其中 9 种候选溶剂对 B. braunii 具有生物相容性。这种生物相容性往往与高相对分子质量和高沸点有关，但强烈依赖于溶剂的化学结构。低极性对于生物相容性至关重要，而计算的辛醇-水分配系数或反相高效液相色谱（HPLC）确定的容量因子是与 B. braunii 生物相容性的合适预测因子。直接从藻类培养物中获得高碳氢化合物回收率需要相对极性的溶剂，因此不利于保持细胞活力。弱极性溶剂不易到达细胞表面，这似乎既能保护藻类，又能防止 B. braunii 外壁中储存的碳氢化合物大量回收。为了实现高回收率，必须用过滤浓缩的藻类进行溶剂接触。然后，在短接触时间内，无需损害细胞活力，就可以回收大量的 B. braunii 碳氢化合物。在这些条件下，相关的溶剂性质是对非极性碳氢化合物的亲和力，在 30 分钟接触后，正己烷的回收率最高，约为 70%。
