Blackberry (Rubus fruticosus) leaf

The blackberries (also called bramble or occasionally "bramble raspberry") are a widespread and well known group of several hundred species, a number of which are closely related apomictic microspecies, native throughout the temperate Northern hemisphere.

The flowers are produced in late spring and early summer on short racemes on the tips of the flowering laterals. Each flower is about 2-3 cm in diameter with five white or pale pink petals. The fruit, in botanical terminology, is not a berry, but an aggregate fruit of numerous drupelets ripening to a black or dark purple fruit, the "blackberry". It will tolerate poor soil, and is an early colonist of wasteland and building sites.

The blackberry is known to contain polyphenol antioxidants, naturally occurring chemicals that can upregulate certain beneficial metabolic processes in mammals. The astringent blackberry root is sometimes used in herbal medicine as a treatment for diarrhea and dysentery. Blackberries are notable for their high nutritional contents of dietary fiber, vitamin C, vitamin K, folic acid, a B vitamin, and the essential mineral manganese. Blackberries rank highly among fruits for antioxidant strength, particularly due to their dense contents of polyphenolic compounds, such as ellagic acid, tannins, ellagitannins, quercetin, gallic acid, anthocyanins and cyanidins.

Blackberries are exceptional among other Rubus berries for their numerous, relatively large seeds not always preferred by consumers. The seeds, however, are an exceptional nutrient source if chewed, containing rich amounts of omega-3 (alpha-linolenic acid) and -6 fats (linoleic acid), protein, dietary fiber, carotenoids, ellagitannins and ellagic acid.

More info: [link]