Campbell P, Srinivasan R, Knoell T, Phipps D, Ishida K, Safarik J, Cormack T, Ridgway H
Biotechnology Research Department, Orange County Water District, 10500 Ellis Avenue, Fountain Valley, California 92728-8300, USA.
Biotechnol Bioeng. 1999 Sep 5;64(5):527-44.
A series of 23 neutral, anionic, and zwitterionic surfactants were tested at a concentration of 0.1% wt/vol for their influence on attachment of a Mycobacterium sp. to cellulose acetate (CA) and polyamide (PA) reverse osmosis (RO) membranes. Four cell attachment bioassays were used: (1) semiconcurrent addition of surfactant and bacteria to RO coupons (standard assay); (2) surfactant pretreatment of RO membranes (membrane pretreatment assay); (3) surfactant treatment of adsorbed cells (detachment assay); and (4) surfactant pretreatment of mycobacteria (cell pretreatment assay). Seventeen surfactants inhibited attachment to PA membranes, whereas 15 inhibited attachment to CA in standard assays and, in 13 cases, the same surfactant inhibited attachment to both PA and CA. Despite greater cell attachment to PA than CA, surfactants were typically more effective in the former membrane system. More surfactants were effective in impairing cell attachment than in promoting detachment and a number enhanced attachment in membrane pretreatment assays, suggesting surface modification of RO membranes. Cell pretreatment inhibited attachment to CA membranes, suggesting the bacterial surface was also a target for detergent activity. Multivariate regression and cluster analyses indicated that critical micellar concentration (CMC) was positively correlated with Mycobacterium attachment in CA and PA standard assays. Surfactant dipole moment and octanol/water partitioning (LogP) also contributed to detergent activity in the PA system, whereas dipole moment, molecular topology (i.e., connectivity indices), and charge properties influenced activity in the CA system. Influential variables in membrane pretreatment assays included the LogP, topology indices, and charge properties, whereas CMC played a diminished role. Surfactant dipole moment was most influential in CA membrane detachment assays. Increasing system ionic strength by LiBr addition strengthened inhibition of cell attachment to CA membranes by dodecylbenzene sulfonic acid (DBSA) and promoted DBSA adsorption to CA surfaces as indicated by attenuated total reflection Fourier-transform infrared spectrometry. Results indicate that inhibition of bacterial attachment to RO membranes may be maximized by manipulating surfactant molecular structure to optimize surface adsorption behavior.
测试了一系列23种中性、阴离子和两性离子表面活性剂，浓度为0.1%（重量/体积），以研究它们对一种分枝杆菌附着于醋酸纤维素（CA）和聚酰胺（PA）反渗透（RO）膜的影响。使用了四种细胞附着生物测定法：（1）将表面活性剂和细菌半同时添加到RO试片上（标准测定法）；（2）对RO膜进行表面活性剂预处理（膜预处理测定法）；（3）对吸附的细胞进行表面活性剂处理（脱附测定法）；（4）对分枝杆菌进行表面活性剂预处理（细胞预处理测定法）。在标准测定中，17种表面活性剂抑制了对PA膜的附着，而15种抑制了对CA膜的附着，在13种情况下，同一种表面活性剂抑制了对PA和CA膜的附着。尽管细胞对PA膜的附着比对CA膜更多，但表面活性剂通常在前者的膜系统中更有效。与促进脱附相比，更多的表面活性剂在损害细胞附着方面有效，并且在膜预处理测定中有一些表面活性剂增强了附着，这表明RO膜的表面发生了改性。细胞预处理抑制了对CA膜的附着，这表明细菌表面也是去污剂作用的靶点。多元回归和聚类分析表明，在CA和PA标准测定中，临界胶束浓度（CMC）与分枝杆菌的附着呈正相关。表面活性剂偶极矩和正辛醇/水分配系数（LogP）也对PA系统中的去污活性有贡献，而偶极矩、分子拓扑结构（即连接性指数）和电荷性质影响CA系统中的活性。膜预处理测定中的影响变量包括LogP、拓扑指数和电荷性质，而CMC的作用减弱。表面活性剂偶极矩在CA膜脱附测定中最具影响力。如衰减全反射傅里叶变换红外光谱所示，通过添加LiBr增加系统离子强度，增强了十二烷基苯磺酸（DBSA）对细胞附着于CA膜的抑制作用，并促进了DBSA在CA表面的吸附。结果表明，通过操纵表面活性剂分子结构以优化表面吸附行为，可使细菌对RO膜附着的抑制作用最大化。
