Studies on the cultivation and uses of evening primrose (Oenothera spp.) in China

Evening primrose originated in North America and became naturalized in the north-east of China about one hundred years ago, where it has been used as famine food and animal feed. New uses for the seed oil, which contains gamma -linoleic acid (GLA), that have been developed in China and overseas since 1980 have created a much larger commercial demand for the seed. There are eight species of Oenothera L. growing wild in China, of which Oenothera biennis L. is preferred. The maximum annual production of wild evening primrose seed is estimated to be about 3000 tons but, since 1986, evening primrose has also been cultivated for its seed and oil using O. biennis (primarily in the provinces of Jilin, Liaoning, Hebei, and Shandong) to meet the increasing demand. New production techniques have been developed and disseminated and reported seed yields range from 750 to 3000 kg ha(-1). Commercial production follows a cyclical pattern, with the largest harvest to date, in 1999, estimated at 16000-19000 tons of seed. During 20 years of research on a wide range of oilseed plants, Chinese scientists found that evening primrose oil was antiatherosclerotic, lowered hyperlipidemia and was antithrombotic. The oil was developed and licensed as a drug (which required work on processing technology, physiochemical characteristics, pharmacology, formulation, and clinical studies) and it has been widely used in clinical practice. Further research work has been done on other bioactive properties of evening primrose oil, alternative sources of GLA, the concentration of GLA, the synthesis of prostaglandin E-i, and the development of health care drugs and cosmetics containing evening primrose oil. We believe that the prospects for the future development of evening primrose are good.