Hippophae, the sea buckthorns, are deciduous shrubs in the family Elaeagnaceae. The name sea buckthorn may be hyphenated to avoid confusion with the buckthorns (Rhamnus, family Rhamnaceae). It is also referred to as sandthorn, sallowthorn, or seaberry. Sea buckthorn fruit consists of sugars, sugar alcohols, fruit acids, vitamins (C, E and K), phenolic compounds, carotenoids, fiber, amino acids, minerals and plant sterols. The fruit contains many of these in high amounts, and is thus considered highly nutritious. Species belonging to genus Hippophae accumulate oil both in soft parts and in seed of the fruit. Oil content in soft parts is 1.5–3 % while in seed this is 11% of the fresh weight. For the compositions of sea buckthorn oils, see article: sea buckthorn oil.
Major sugars in sea buckthorn fruits are fructose and glucose, with total sugar content of 2.7-5.3 g/100 ml of juice. Typical sourness of the fruits is due to high content of malic acid (0.8-3.2 g/100 ml of juice) while astringency is related to quinic acid (1.2-2.1 g/100 ml of juice). Major sugar alcohol in fruit is L-quebrachitol (0.15-0.24 g/100 ml of juice). The fruit of the plant has a high vitamin C content – in a range of 114 to 1550 mg per 100 grams with an average content (695 mg per 100 grams), placing sea buckthorn fruit among the most enriched plant sources of vitamin C. Additionally, fruits have high concentrations of carotenoids, vitamin E and vitamin K. The main carotenoids are beta-carotene, zeaxanthin and lycopene while alpha-tocopherol is the major vitamin E compound