Fatty acid profiles and sn -2 fatty acid distribution of γ-linolenic acid-rich Borago species

Abstract

The aim of this work was to assess the seed oils of different Borago species as sources of bioavailable γ-linolenic acid (GLA) by establishing its positional distribution within the triacylglycerol (TAG) structure. To this end, seeds of wild and farmed Borago species were collected and analysed. The highest GLA percentage of total fatty acids (FA) was found in B. morisiana and B. pygmaea (23.1 and 22.9% GLA of total FA, respectively). Other endemic Borago species (B. trabutii and B. longifolia) show a lower GLA content (18.9 and 19.0% of total FA, respectively). Oil content in seeds of B. officinalis ranged from 14.4 to 20.3%, while the GLA percentage of total FA was 15.7–19.4%, which leads to a 2.3–3.7% GLA range in the whole seeds. For endemic Borago, such amounts were 5.6, 5.0, 3.9, and 3.0%, for B. morisiana, B. pygmaea, B. trabutii, and B. longifolia, respectively. The distribution of FA in the sn-2 position of TAG was assessed by enzymatic hydrolysis reaction. The best regiospecific index was found in B. longifolia (0.8) and B. officinalis (1.0). This study provides useful data on novel GLA-rich Borago seed oils, which have potential use in the food and pharmaceutical industries.