Insight into the Influence of Cultivar Type, Cultivation Year, and Site on the Lignans and Related Phenolic Profiles, and the Health-Promoting Antioxidant Potential of Flax (Linum usitatissimum L.) Seeds

Abstract

Flaxseeds are a functional food representing, by far, the richest natural grain source of lignans, and accumulate substantial amounts of other health beneficial phenolic compounds (i.e., flavonols, hydroxycinnamic acids). This specific accumulation pattern is related to their numerous beneficial effects on human health. However, to date, little data is available concerning the relative impact of genetic and geographic parameters on the phytochemical yield and composition. Here, the major influence of the cultivar over geographic parameters on the flaxseed phytochemical accumulation yield and composition is evidenced. The importance of genetic parameters on the lignan accumulation was further confirmed by gene expression analysis monitored by RT-qPCR. The corresponding antioxidant activity of these flaxseed extracts was evaluated, both in vitro, using ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and iron chelating assays, as well as in vivo, by monitoring the impact of UV-induced oxidative stress on the lipid membrane peroxidation of yeast cells. Our results, both the in vitro and in vivo studies, confirm that flaxseed extracts are an effective protector against oxidative stress. The results point out that secoisolariciresinol diglucoside, caffeic acid glucoside, and p-coumaric acid glucoside are the main contributors to the antioxidant capacity. Considering the health benefits of these compounds, the present study demonstrates that the flaxseed cultivar type could greatly influence the phytochemical intakes and, therefore, the associated biological activities. We recommend that this crucial parameter be considered in epidemiological studies dealing with flaxseeds.

A Quick, Green and Simple Ultrasound-Assisted Extraction for the Valorization of Antioxidant Phenolic Acids from Moroccan Almond (<em>Prunus dulcis</em> (Mill.) D.A.Webb) Cold-Pressed Oil Residues

“…An in cellulo antioxidant assay, using yeast cells, based on the measurement of membrane lipid peroxide was carried out with the thiobarbituric acid (TBA; Sigma Aldrich, Saint-Quentin Fallavier, France) method as described by Garros et al [20]. In details, yeast cells (Saccharomyces cerevisiae) strain MAV203 (Invitrogen, Thermo Fisher Scientific, Villebon-sur-Yvette, France) were grown aerobically at 30 °C in an orbital shaker (150 rpm) in complete 2.0% (w/v) glucose YPD medium (Sigma Aldrich, Saint-Quentin Fallavier, France).…”

“…It is generally accepted that the genetic background, but also the environmental conditions, such as the location (i.e., soil conditions) or the climate, could have a great influence on the accumulation of phenolic compounds [3,16,20,28,32,33]. The present preliminary results obtained from 3 native genotypes cultivated on the same year at 3 different location sites from Eastern Morocco, suggested a prominent influence of genetic over environment, since the impact of the genotype was more important than the influence of the cultivation site.…”

“…The protective antioxidant action developed by plant extracts can be influenced by many internal and external factors impacting their phytochemical compositions such as genetics (the use of different genotypes in our case) but also the environment (the use of different culture sites in our case) [3,16,20,28,32,33]. Furthermore, their antioxidant activity is generally based on complex mechanisms which, in order to shorten, depending on the nature of the compounds present in the extract, can be based in particular on radical scavenging mechanisms.…”

Almond Skin Extracts and Chlorogenic Acid Delay Replicative Aging by Enhanced Oxidative Stress Response Involving SIR2 and SOD2 in Yeast

“…The thiobarbituric acid (TBA; Sigma Aldrich, Saint-Quentin Fallavier, France) method described by Garros et al [26] was used for the measurement of membrane lipid peroxide. Briefly, about 10 8 yeast cells ground in double distilled water were centrifuged for 10 min at 10,000 xg.…”

“…Overall, the previous results suggest that AE and CHL may extend the replicative lifespan of the yeast through an antioxidant mechanism. The impact of UV-C-induced oxidative stress on DBY746 yeast was examined to test this hypothesis using our published protocol [6,23,26]. The resulting yeast survival, estimated with a quantitative colony counting assay [49], and ROS/RNS production are presented in Figure 4.…”