Antifouling and antibacterial bioactive metabolites of marine fungus (terrein)/polyamide thin-film composite reverse osmosis membranes for desalination applications

Abstract

Marine fungi-derived (+)-terrein is grafted onto a reverse osmosis polyamide membrane using glutaraldehyde, forming a thin film composite (Terrein-PA) membrane. This membrane exhibits improved water permeability, antifouling and antibacterial properties. Compared to conventional reverse osmosis membranes, Terrein-PA membrane shows a 51.0 % increase in permeability (7.4 L/m2·h·bar) due to its beneficial hydroxyl groups. It also effectively inhibits the growth of gram-positive and gram-negative bacteria, achieving antibacterial rates of 98.0 % and 94.9 %, respectively. This reduces microorganism adhesion, extending the membrane's service life. The use of natural (+)-terrein is safer for human health than chlorine treatments. Furthermore, when contaminated with bovine serum albumin, Terrein-PA membrane achieves a flux recovery rate of 90.9 % and a total contamination rate of 12.3 %. This study introduces an innovative approach to produce secure antibacterial reverse osmosis membranes with prolonged lifespan.