Surfactant induces ROS-mediated cell membrane permeabilization for the enhancement of mannatide production

Abstract A surfactant was a substance that had an important influence on the excretion of intracellular substances. In this work, it was found that cetyltrimethylammonium bromide (CTAB) inhibited cell viability but increased the mannatide production by optimizing the addition time. Results revealed that CTAB changed cell surface properties (cell surface hydrophobicity and Zeta potential was increased from 3% to 14% and −14.5 mV to −10.2 mV, respectively) and permeabilized cell membrane (intercellular ATP content was decreased from 28.599 μg/g to 9.737 μg/g while extracellular ATP content was increased from 33.051 μg/g to 82.809 μg/g; the concentrations of K+ and Ca2+ were increased to 3.9 mg/L and 2.1 mg/L, respectively; membrane potential was formed). Moreover, the images of scanning electron micrographs indicated distinct morphological changes and disruption on the surface of the cells. Further pyridinium iodides staining showed CTAB could induce cell apoptosis from 4.24% to 31% with increasing the relative intracellular reactive oxygen species (ROS) from 0.11% to 7.31%. It is the most noteworthy that the addition of CTAB increased the mannatide production to 1.46 g/L, 98.6% higher than that of untreated cells. Consequently, the utilization of CTAB for the preparation of mannatide provide theoretical foundation for the further large-scale production.