AbstractBACKGROUNDAntrodia camphorata is proven to probably inhibit the neurotoxicity of amyloid β‐peptide (Aβ), known as a risk factor toward the development of Alzheimer's disease. Deep ocean water (DOW), drawn from an ocean depth of more than 200 m, has proven to stimulate the growth and metabolite biosynthesis of fungi owing to its rich minerals and trace elements. Based on these advantages of DOW, this study used statistical response surface methodology (RSM) to investigate the effects of DOW on the growth and anti‐Aβ‐induced neurocytotoxicity ability of A. camphorata.RESULTSThe results showed that DOW was useful for increasing the biomass of A. camphorata and enhancing its neuroprotective capability. The anti‐Aβ40‐induced neurocytotoxicity ability of filtrate was increased via raising the mycelium‐secreted components. Furthermore, the anti‐Aβ40‐induced neurocytotoxicity ability of mycelium was also increased by the DOW‐stimulated intracellular antioxidants. Using 80% DOW concentration, initial pH 3.3 and 20% inoculum size as the optimal culture conditions of A. camphorata significantly stimulated the biomass and mycelium‐mediated Aβ40‐induced cell viability from 302 ± 14 mg per 100 mL and 49.2 ± 2.2% to 452 ± 33 mg per 100 mL and 65.0 ± 7.4% respectively.CONCLUSIONThis study indicated that DOW could be used as a promising supplementary for the production of A. camphorata secondary metabolites with strong antioxidant activity to protect neuron cells from damage based on Aβ stimulation cytotoxicity. © 2016 Society of Chemical Industry