Wild Asparagus Shoots Constitute a Healthy Source of Bioactive Compounds.

Wild Asparagus shoots are consumed worldwide, although most species remain understudied. In this work, a total of four wild Asparagus species were collected from different locations and analyzed compared with farmed A. officinalis. Shoots were screened for (i) phenolic compounds by HPLC-DAD and LC-MS; (ii) total phenolic acids and total flavonoid content by the Folin-Ciocalteu and aluminum chloride methods; (iii) vitamin C by HPLC-DAD; (iv) antioxidant activity by the DPPH and ABTS•+ methods; and (v) the in vitro antiproliferative activities against HT-29 colorectal cancer cells by the MTT assay. Phenolics ranged from 107.5 (A. aphyllus) to 605.4 mg/100 g dry weight (dw) (A. horridus). Vitamin C ranged from 15.8 (A. acutifolius) to 22.7 mg/100 g fresh weight (fw) (A. officinalis). The antioxidant activity was similar in all species, standing out in A. officinalis with 5.94 (DPPH) and 4.64 (ABTS) mmol TE/100 g dw. Among phenolics, rutin reached the highest values (574 mg/100 g dw in A. officinalis), followed by quercetin, nicotiflorin, asterin, and narcissin. The MTT assay revealed the inhibitory effects of ethanol extracts against HT-29 cancer cells, highlighting the cell growth inhibition exercised by A. albus (300 µg/mL after 72 h exposure to cells). This work improves knowledge on the phytochemicals and bioactivities of the shoots of wild Asparagus species and confirms their suitability for use as functional foods.

γ-Linolenic and Stearidonic Acids from Boraginaceae of Diverse Mediterranean Origin.

Thirty Boraginaceae species from different tribes were evaluated in a search of γ-linolenic (GLA, 18:3n-6) and stearidonic acid (SDA, 18:4n-3)-rich oils. The high GLA percentages were found in the seed oils of Symphytum bulbosum and S. tuberosum subsp. tuberosum (27.6 and 27.2 % of total fatty acids (FA)), which are unusually high values for GLA-oils in the current literature. On the whole seed, noticeable GLA percentages were found in S. grandiflorum, S. tuberosum subsp. tuberosum and Borago officinalis (7.43, 4.90, and 4.51 g/100 g, respectively). The main SDA-taxa detected in this study were Buglossoides arvensis, B. incrassata and Glandora oleifolia (21.3, 18.9, and 16.3 % of total fatty acids). On total seed weight, Glandora rosmarinifolia showed the highest SDA content (3.57 g/100 g). Finally, the higher FA contents were found in S. grandiflorum and Paramoltkia doerfleri seeds (35.2 and 37.0 g/100 g, respectively). Principal component analysis showed that similarities in FA profiles allow grouping species as botanical criteria for Boraginaceae tribes do, while the FA groupings confirm the metabolic activities of desaturase and elongase enzymes. Data on the FA composition of the seed oils analyzed here suggest their potential use as functional foods and can be considered as novel sources of SDA and GLA.

Ribes taxa: A promising source of γ-linolenic acid-rich functional oils.

Fifty Ribes species and R. nigrum-based cultivars from eight Ribes sections were surveyed for γ-linolenic acid (GLA, 18:3, n-6)- and stearidonic acid (SDA, 18:4, n-3)-rich oils. R. pallidiflorum, R. glabellum and R. pubescens seed oils contain noticeable GLA amounts: 13.3, 11.8, and 11.9% of total fatty acids (FA), respectively. However, the highest GLA contents were found in the seed oils of several blackcurrant cultivars, highlining Ribes 'Myuryucheene' with 20.2% GLA of total FA. Principal Component Analysis showed that similarities in FA profiles allow grouping species as botanical criteria for Ribes sections do. The main GLA-taxa detected in this study correspond to blackcurrant cultivars, all of them native to Siberia. Considering that such cultivars are notable fruit-producers, its cultivation in Siberia besides producing fruits in very difficult agronomic areas, could produce a valuable by-product, i.e. the seeds, which will add economic value to agricultural systems if devoted to GLA-rich oils extraction.

Sardinian Boraginaceae are new potential sources of gamma-linolenic acid.

The aim of this work was to establish the richness in γ-linolenic acid (GLA, 18:3n6) and stearidonic acid (SDA, 18:4n3) of several Sardinian Boraginaceae species. To this end, seeds of selected species were collected from their natural habitats and analysed. The highest GLA contents were found in the seed oils of two endemic Borago taxa, i.e. B. morisiana (24.4 and 24.6% GLA of total fatty acids for samples from San Pietro Island and Sardinia Island, respectively), and 22.9% GLA for B. pygmaea. Both Borago species contained more GLA than B. officinalis collected in the same ecosystems. SDA was found in significant amounts in Echium plantagineum seed oil from the Lattias Mountains (15% SDA of total fatty acids). It is notable that both Borago GLA-rich species are under threat of extinction, thus revealing the importance of the preservation of the natural Sardinian ecosystems for endangered species and human health.