Development and Application of a Novel Bioreactor with Loofa (Luffa cylindrica) Sponge as a Carrier For Cell Immobilization.

通过简单地用细胞悬浮液接种含有丝络海绵床的反应器，可以实现絮凝细胞的有效固定化。细胞被困在海绵的晶格中，并生长到高细胞密度。对于非絮凝细胞，通过添加絮凝剂（壳聚糖）诱导絮凝，并对絮凝细胞进行有效的固定化。通过将孢子或均质菌丝接种到含有丝瓜海绵床的反应器中来固定化真菌。孢子在海绵的晶格结构内萌发，产生的菌丝在海绵上缠绕（固定）。虽然单个圆柱形海绵固定床的传质效果较好，但使用切片丝瓜海绵构建床时，单位反应器体积的海绵数量和单位海绵固定细胞数量更高。因此，圆柱形或切片丝瓜海绵应分别用于好氧发酵或厌氧发酵过程。以固定化絮凝法（酿酒酵母菌）或非絮凝法（芸苔假丝酵母）作为厌氧发酵的应用实例，以糖蜜和蔗糖为培养基连续生产乙醇。这些过程在很长一段时间内是稳定的。在好氧过程中，固定化丝瓜海绵上的川曲霉可以长期连续生产葡萄糖淀酵酶。此外，利用固定化的awamori曲霉和酿酒酵母的组合实现了淀粉连续直接乙醇生产。上述结果表明，具有代表性的絮凝和非絮凝发酵微生物（酵母、细菌和真菌）可以有效地固定在丝瓜海绵上。此外，通过使用圆柱形或切片丝瓜海绵，可以构建适合好氧或厌氧发酵过程的固定床。由此可见，丝瓜海绵生物反应器在多种发酵工艺中具有广阔的应用前景。少

Efficient immobilization of flocculating cells can be achieved by simply inoculating a reactor containing a bed of the loofa sponge with the cell suspension. The cells were trapped inside the lattice of the sponge and grew to high cell densities. In the case of non-flocculating cells, flocculation was induced by addition of flocculating agent (chitosan) and the flocculated cells were efficiently immobilized as described above. Fungi was immobilized by inoculating either spores or homogenized hyphae into a reactor containing a bed of the loofa sponge. The spores germinated inside the lattice structure of the sponge and the resulting hyphae were entangled (immobilized) on the sponge.Although mass transfer was better in a fixed bed made of a single cylindrical sponge, the amounts of sponge per unit reactor volume and the immobilized cells per unit sponge were higher when sliced loofa sponges were used for bed construction. Thus cylindrical or sliced loofa sponges should be used for aerobi … More c or anaerobic fermentation processes, respectively.As examplex of application to anaerobic fermentation, immobilized flocculating (Saccharomyces cerevisiae) or non-flocculating (Candida brassicae) was used for continuous ethanol production from molasses and sucrose medium. The processes were stable for long periods of time. In the case of aerobic processes, long term continuous glucoamylase production by Aspergillus awamori immobilized on loofa sponge was possible. Furthermore, continuous direct ethanol production from starch was achieved by using a combination of immobilized Aspergillus awamori and Saccharomyces cerevisiae.The above results have shown that representative flocculating and non-flocculating fermentation microorganisms (yeast, bacteria and fungi) can be efficiently immobilized on loofa sponge. Furthermore, by using either the cylindrical or sliced loofa sponge, suitable fixed beds for aerobic or anaerobic fermentation processes can be constructed. It can be thus concluded that bioreactor with loofa sponges has great potential for application in a wide range of fermentation processes. Less