Borago officinalis L. as an important source of natural aromatic compounds

Abstract

Borage is planted for medicinal and culinary purposes and is also grown commercially to produce borage seed oil, high in GLA (γ-linolenic acid), which is used as a natural flavouring, food, and nutritional supplement. Borage antioxidants have potential in skin health products as UV absorbing components. The borage essential oil extracted by hydrodistillation contains important amounts of the valuable aroma compound 2.6 nonadienal (NDAL). Borage is grown mainly in Europe (England, the Netherlands) and in the United States (mostly in North Dakota) and Canada for commercial seed production. Seven varieties of borage were evaluated in the experiment. The average plant height ranged from 701 to 765 mm (locality Piešt’any). The leaves of borage are characterised by a ground rosette at the base, the lower leaves with petioles 20-80 mm long are mostly elliptic, entire edged. The leaf characteristics were described: leaf length 115,6-166,0 mm, leaf width 69,9-99,4 mm, leaf circumference 311,4-450,5 mm and leaf area 5403-11426 mm2. Borage flowers - predominantly large, long-stalked, 15-30 mm in diameter, mostly blue in colour, except for genotype 7/17 which had white flowers. 1000-seed weight varied 13.6-15.2 g. The evaluation of yield-forming elements, the average weight of fresh biomass per plant was quantified at 520 g (locality Piešt’any) and 243-295 g (locality Plavnica), the average weight of biomass of dry plant was 115 g with a drying ratio of 4.52:1. The concentration of NDAL obtained from borage biomass ranged from 8.24-10.97 mg NDAL/kg for flower and 3.83-8.55 mg NDAL/kg for leaves, depending on the phenophase.