2 Department of Biochemistry and Food Chemistry, University of Turku, FIN-20014 Turku, Finland

Berries of sea buckthorn (Hippophaë rhamnoides) are rich in a wide range of hydrophilic and lipophilic bioactive compounds and are a valuable raw material for functional foods and nutraceuticals. Great variation is found in the composition of sea buckthorn berries and berry fractions. It is often difficult to compare compositional data in literature because of different analysis methods and pretreatment of the berries. Systematic studies on the influence of various factors on the composition of the berries are important in guiding plant breeding, cultivation and industrial utilization of sea buckthorn. In the present study, berries of different growth sites, belonging to three major subspecies, are collected from China, Finland and Russia in four consecutive years. A comprehensive compositional mapping was carried out by extensive analysis of vitamin C, sugars, fruit acids, aromas, lignans, flavonoids, fatty acids, tocopherols, tocotrienols, carotenoids, and plant sterols of these berries. The difference between subspecies and the influence of harvesting times as well as annual variation is studied. While difference is found in most of the compounds analysed, the fatty acid composition of seed oil is identical among samples of different origins and harvesting dates. Subsp. sinensis from China has the highest content of vitamin C (20 times higher than subsp. mongolica), sugars (2-5 times higher than subsp. rhamnoides and mongolica) and vitamin E (2 times higher than other two subspecies) in fresh berry and the lowest content of seed and berry oils. Subspecies mongolica is the richest source of seed oil and berry oil and palmitoleic acid. Harvesting date strongly influences the composition of the seedless fraction, especially sugars and vitamin C. The different weather conditions among harvesting years directly influence the water content of the fresh berries and have a significant impact on the composition of the seedless parts. Based on large number of samples, the present study provides an overall picture of the compositional characteristics of sea buckthorn berries.