Hippophae is a genus of flowering plants in the family Elaeagnaceae. They are deciduous shrubs. They are exceptionally hardy plants, able to withstand winter temperatures as low as . As Hippophae species develop an aggressive and extensive root system, they are planted to inhibit soil erosion and used in land reclamation for their nitrogen fixing properties, wildlife habitat, and soil enrichment. Hippophae berries and leaves are manufactured into various human and animal food and skincare products.

Species and description

The shrubs reach tall, rarely up to in central Asia. The leaf arrangement can be alternate or opposite. includes the following species:

  • Hippophae × goniocarpa is a natural hybrid of H. neurocarpa and H. sinensis which grows in mountainous regions in Nepal, Mongolia and China.
  • Hippophae gyantsensis
  • Hippophae litangensis
  • Hippophae neurocarpa
  • Hippophae rhamnoides : Common sea buckthorn has dense and stiff branches, and are very thorny. The leaves are a distinct pale silvery-green, lanceolate, long, and less than broad. It is dioecious, with separate male and female plants. The male produces brownish flowers which produce wind-distributed pollen. The female plants produce orange berries in diameter, soft, juicy, and rich in oils. The roots distribute rapidly and extensively, providing a nonleguminous nitrogen fixation role in surrounding soils.
  • Hippophae salicifolia (willow-leaved sea buckthorn) is restricted to the Himalayas, to the south of the common sea buckthorn, growing at high altitudes in dry valleys; it differs from H. rhamnoides in having broader (to ) and greener (less silvery) leaves, and yellow berries. A wild variant occurs in the same area, but at even higher altitudes in the alpine zone. It is a low shrub not growing taller than with small leaves long.
  • Hippophae sinensis
  • Hippophae tibetana

thumb|right|[[Hippophae rhamnoides|Common sea buckthorn]]

Taxonomy and name

Hippophae is a small genus of Elaeagnaceae having a terminal taxon with seven species recognized, as of 2002. Hippophae rhamnoides is a highly variable species with eight subspecies. In western Europe, it is largely confined to sea coasts where salt spray off the sea prevents other larger plants from outcompeting it. In central Asia, it is more widespread in dry semi-desert sites where other plants cannot survive the dry conditions.

In central Europe and Asia, it also occurs as a sub-alpine shrub above the tree line in mountains, and other sunny areas such as river banks where it has been used to stabilize erosion.

Varieties

Between 1945 and 1991, Soviet and German horticulturists developed new varieties with greater nutritional value, larger berries, different ripening months and branches that are easier to harvest. Over the past 20 years, experimental crops have been grown in the United States, one in Nevada and one in Arizona, and in several provinces of Canada.

Genetics

A study of nuclear ribosomal internal transcribed spacer sequence data showed that the genus can be divided into three clades:

  • H. tibetana
  • H. rhamnoides with the exception of H. rhamnoides ssp. gyantsensis (=H. gyantsensis)
  • remaining species

A study using chloroplast sequences and morphology, unless bletted (frosted to reduce the astringency) and/or mixed as a drink with sweeter substances such as apple or grape juice. Additionally, malolactic fermentation of sea buckthorn juice reduces sourness, enhancing its sensory properties. The mechanism behind this change is transformation of malic acid into lactic acid in microbial metabolism.

When the berries are pressed, the resulting sea buckthorn juice separates into three layers: on top is a thick, orange cream; in the middle, a layer containing sea buckthorn's characteristic high content of saturated and polyunsaturated fats; and the bottom layer is sediment and juice. The upper two layers contain fat sources applicable for cosmetic purposes and can be processed for skin creams and liniments, whereas the bottom layer can be used for edible products such as syrup. Fruit drinks were among the earliest sea buckthorn products developed in China. Sea buckthorn-based juice is common in Germany and Scandinavian countries. It provides a beverage rich in vitamin C and carotenoids.

For its troops confronting low winter temperatures (see Siachen), India's Defence Research and Development Organisation established a factory in Leh to manufacture a multivitamin herbal beverage based on sea buckthorn juice.

The seed and pulp oils have nutritional properties that vary under different processing methods. Sea buckthorn oils are used as a source for ingredients in several commercially available cosmetic products and nutritional supplements. Branches may be used by florists for designing ornaments.

In northwestern China, sea buckthorn shrubs have been planted on the bottoms of dry riverbeds to increase water retention of the soil, thus decreasing sediment loss. Sea buckthorn was once distributed free of charge to Canadian prairie farmers by PFRA to be used in shelterbelts.

Folk medicine and research

Sea buckthorn has been used over centuries in traditional medicine. As of 2022, no sea buckthorn products are approved as prescription drugs by any national regulatory agency.

In Mongolia, there is an active National Association of Seabuckthorn Cultivators and Producers.

See also

  • Sea buckthorn oil
  • Wolfberry, a native Asian plant occasionally mistaken for sea buckthorn

References

Further reading

  • Todd, J. Introduction to sea-buckthorn, Ontario Ministry of Food, Agriculture and Rural Affairs, August, 2022
  • United States Department of Agriculture Seaberry Profile
  • Plants for a Future
  • Purdue University list of articles