Plant seeds could provide ‘important’ source of omega-3 fatty acids
Searching for potential new sources of plant derived omega-3 polyunsaturated fatty acids (PUFAs) in the seed oils of less well known plants could provide new sources for the in demand compounds, say researchers writing in the European Journal of Lipid Science and Technology.
Led by Dr Katrin Kuhnt from Friedrich Schiller University, Germany, the research team analysed the seed oil composition of 30 plant species – to identify potential new sources of the omega-3 PUFA alpha-linolenic acid (ALA) and stearidonic acid (SDA), and of the n-6 PUFA gamma-linolenic acid (GLA).
“Unfortunately, due to the increasing world population, overfishing of the seas and generally low amounts of n-3 PUFA in major oil crops, there is a demand for new sources of omega-3 PUFA,” said Kuhnt and her colleagues.
She said that one approach to meeting the increasing demand “involves searching for potential vegetable sources of omega-3 PUFA; especially those rich in ALA and SDA.”
Commenting on the research, Harry Rice, PhD, VP of regulatory & scientific affairs for the Global Organization for EPA and DHA Omega-3s (GOED), told NutraIngredients that the demonstrated low conversion from dietary ALA to cardio-protective levels of EPA and DHA means that such protection can only be achieved through direct consumption of EPA or DHA.
However, the omega-3 expert added that SDA is converted to EPA more readily – noting that two recent clinical trials have demonstrated that SDA-enhanced soybean oil can significantly improve the omega-3 Index – an emerging marker of cardiovascular health.
The research team analysed the seeds from 30 species of plants – mainly of Boraginaceae and Primulaceae genus – to identify potential new sources of ALA, SDA and GLA.
They reported that the fatty acid distribution differed enormously between genera of the same family, with the Echium species (Boraginaceae) containing the highest amount of total omega-3 PUFA (47.1%).
Further species of Boraginaceae rich in both SDA and GLA were Omphalodes linifolia (8.4, 17.2%, respectively), Cerinthe minor(7.5, 9.9%) and Buglossoides purpureocaerulea (6.1, 16.6%), revealed the authors.
They added that Cannabis sativa cultivars (Cannabaceae) were rich in linoleic acid (57.1%), but poor in SDA and GLA (0.8, 2.7%).
“Several of the presented plant seeds contain considerable amounts of omega-3 PUFA and GLA, which could be relevant for nutritional purposes due to their biological function,” said the researchers.
They noted that, in particular, plant-derived SDA is “a promising precursor” for the synthesis of omega-3 long-chain PUFA in humans.
“Considering the overfishing of the seas – the integration of omega-3 PUFA-rich plant oils, particularly SDA-containing oils, into the diet could be a promising step forward towards ensuring the n-3 PUFA supply of an increasing world population,” said Kuhnt and her team.
“It is therefore assumed that screening of the fatty acid composition of less-researched plant seed oils may provide a nutritional benefit,” they argued.
Adding further comment on the study, Rice said: “Another question begging to be answered is whether or not there is utility for SDA for something like brain health.”
Source: European Journal of Lipid Science and Technology
Volume 114, Issue 2, pages 153–160, doi: 10.1002/ejlt.201100008
“Searching for health beneficial n-3 and n-6 fatty acids in plant seeds”
Authors: K. Kuhnt, C. Degen, A. Jaudszus, G. Jahreis