This invention provides novel antioxidants comprising hydroquinone substituted polyunsaturated fatty acids. Such fatty acids can be obtained from crude kombo butter and are suitable for preventing oxidation of various organic materials. In particular, the invention relates to the use of these fatty acids as antioxidants in the treatment of cancer, the inhibition of proliferation of cells, in lowering levels of cholesterol both in vivo and in vitro and in the treatment of cognitive disorders, including but not limited to Alzheimer's disease.