Callewaert R, De Vuyst L
Department of Biotechnology, Faculty of Sciences, Vrije Universiteit Brussel (VUB), Belgium.
Bioseparation. 1999;8(1-5):159-68.
Expanded bed adsorption using a strong cation exchanger allowed the direct isolation of amylovorin L471, a bacteriocin from Lactobacillus amylovorus DCE 471, from the fermentation medium. The pH of the loading and elution buffer were optimised in a packed bed with cell-free culture supernatant. Bound bacteriocin was eluted with 1.0 M NaCl. The highest recovery (30%) was obtained at the lowest pH (3.6). At higher pH values the recovery was lower, namely 12%, 15% and 7% at pH 4.5, 6.5 and 8.0, respectively. In expanded bed mode, direct isolation of the bacteriocin from the fermentation medium at pH 3.6 (loading and elution) initially resulted in a recovery of 12%. After optimisation of the pH (loading and elution at pH 3.6 and 6.5, respectively), the recovery for amylovorin L471 increased up to 30% and higher. Recovery of enterocin A from Enterococcus faecium CTC 492 fermentation medium averaged 15% (loading and elution at pH 3.6 and 6.0, respectively). With pediocin, produced by Pediococcus acidilactici ATCC 8042, 26% recovery was obtained at a pH of 6.5 during loading and elution. Low recoveries can be ascribed to non-optimal operation conditions (pH of loading and elution buffer), inactivation of the bacteriocin on a cationic resin, and the formation of more insoluble and less active, strongly hydrophobic bacteriocin aggregates upon further purification.
使用强阳离子交换剂的扩张床吸附法可直接从发酵培养基中分离出支链淀粉乳杆菌DCE 471产生的细菌素支链淀粉乳杆菌素L471。在装有无细胞培养上清液的填充床中对上样和洗脱缓冲液的pH值进行了优化。结合的细菌素用1.0 M NaCl洗脱。在最低pH值（3.6）下获得了最高回收率（30%）。在较高pH值下回收率较低，在pH 4.5、6.5和8.0时分别为12%、15%和7%。在扩张床模式下，在pH 3.6（上样和洗脱）条件下直接从发酵培养基中分离细菌素，最初回收率为12%。在优化pH值（分别在pH 3.6和6.5下上样和洗脱）后，支链淀粉乳杆菌素L471的回收率提高到30%及更高。从粪肠球菌CTC 492发酵培养基中回收肠球菌素A的平均回收率为15%（分别在pH 3.6和6.0下上样和洗脱）。对于嗜酸乳杆菌ATCC 8042产生的片球菌素，在上样和洗脱pH值为6.5时回收率为26%。回收率低可归因于非最佳操作条件（上样和洗脱缓冲液的pH值）、细菌素在阳离子树脂上的失活以及在进一步纯化时形成更多不溶性且活性较低的强疏水性细菌素聚集体。
