Oil and air dispersion in a simulated fermentation broth as a function of mycelial morphology
Oil and air dispersion in a simulated fermentation broth as a function of mycelial morphology
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DOI：
10.1021/bp020118e
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发表时间：
2003-03-01
影响因子：
2.9
通讯作者：
Galindo, E
中科院分区：
文献类型：
--
作者：
Lucatero, S;Larralde-Corona, CP;Galindo, E
为了研究哈兹木霉菌丝形态对蓖麻油和空气分散的影响，模拟了形态复杂菌丝多相发酵的培养条件。利用与混合槽相连接的图像分析系统对油滴和气泡进行了测量。可以清楚地观察到所涉及的相的复杂相互作用。加入体系的生物量形态类型（球团或分散菌丝体）影响了液滴和气泡的直径和大小分布。由于肉汤的高表观粘度，分散菌丝体比球团获得了更大的油滴，这导致了功率的下降，减少了油滴的破裂。出乎意料的是，分散菌丝观察到的气泡尺寸比球团小，这一现象可以解释为在高生物量浓度下分散菌丝发生分离。产生了非常复杂的油滴，其中含有气泡和大量可能由小水滴组成的结构。气泡的位置受生物量形态的影响。随着分散菌丝浓度的增加，油捕获气泡的体积百分比从32%增加到80%。在所有生物量浓度下，观察到几乎恒定（32%）的油捕获气泡呈颗粒状形态。结果证明了相相互作用的高度复杂性和菌丝形态在这一过程中的重要性。
The culture conditions of a multiphase fermentation involving morphologically complex mycelia were simulated in order to investigate the influence of mycelial morphology (Trichoderma harzianum) on castor oil and air dispersion. Measurements of oil drops and air bubbles were obtained using an image analysis system coupled to a mixing tank. Complex interactions of the phases involved could be clearly observed. The Sauter diameter and the size distributions of drops and bubbles were affected by the morphological type of biomass (pellets or dispersed mycelia) added to the system. Larger oil drop sizes were obtained with dispersed mycelia than with pellets, as a result of the high apparent viscosity of the broth, which caused a drop in the power drawn, reducing oil drop break-up. Unexpectedly, bubble sizes observed with dispersed mycelia were smaller than with pellets, a phenomenon which can be explained by the segregation occurring at high biomass concentrations with the dispersed mycelia. Very complex oil drops were produced, containing air bubbles and a high number of structures likely consisting of small water droplets. Bubble location was influenced by biomass morphology. The percentage (in volume) of oil-trapped bubbles increased (from 32 to 80%) as dispersed mycelia concentration increased. A practically constant (32%) percentage of oil-trapped bubbles was observed with pelleted morphology at all biomass concentrations. The results evidenced the high complexity of phases interactions and the importance of mycelial morphology in such processes.