Antioxidant activity and bioactive compounds of ten Portuguese regional and commercial almond cultivars

Abstract

a b s t r a c tThe antioxidant properties of different almond cultivars (cv.), either regional (Casanova, Duro Italiano, Molar, Orelha de Mula and Pegarinhos cv.) or commercial (Ferraduel, Ferranhês, Ferrastar and Guara cv.) were evaluated through several chemical and biochemical assays: DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, reducing power, inhibition of b-carotene bleaching, inhibition of oxidative hemolysis in erythrocytes, induced by 2,2 0 -azobis(2-amidinopropane)dihydrochloride (AAPH), and inhibition of thiobarbituric acid reactive substances (TBARS) formation in brain cells, all used as models for the lipid peroxidation damage in biomembranes. The EC 50 values were calculated for all the methods in order to evaluate the antioxidant efficiency of each almond cultivar. Bioactive compounds such as phenols and flavonoids were also obtained and correlated to antioxidant activity. The results obtained were quite heterogeneous, revealing significant differences among the cultivars assayed. Duro Italiano cv. revealed better antioxidant properties, presenting lower EC 50 values in all assays, and the highest antioxidants contents. The protective effect of this cultivar on erythrocyte biomembrane hemolysis was maintained during 4 h.

Antioxidant and antiproliferative activities of phenolics isolated from fruits of Himalayan yellow raspberry (Rubus ellipticus)

“…The ABTS cation radical scavenging activity was determined as described (Barreira et al 2008). The diluted fruit extracts (50 μl) were allowed to react with fresh ABTS solution (3.0 ml) for 6 min, and then absorbance was measured at 734 nm.…”

“…Ferric reducing power assay was performed according to Barreira et al (2008). The diluted extract was mixed with sodium phosphate buffer (2.5 ml, 200 mM, pH 6.6) and potassium ferricyanide solution (1 % w/v, 2.5 ml) and incubated at 50°C for 20 min.…”

“…Additionally, fruits phenolics have also been demonstrated to possess strong antiproliferative properties (Johnson et al 2011;Sun et al 2002;Liu et al 2002;Seerama et al 2005). Due to the cancer protective effects, and super antioxidant properties, fruits are gaining world wide interest for the exploration of their polyphenolic contents and their various health promoting properties (Kahkonen et al 2001;Leong and Shui 2002;Moyer et al 2002;Karadeniz et al 2005;Marinova et al 2005;Barreira et al 2008;Lim et al 2007;Meda et al 2008).…”

An almond-enriched diet increases plasma α-tocopherol and improves vascular function but does not affect oxidative stress markers or lipid levels

“…Additional nutrients in almonds that associate with positive cardiovascular outcomes include antioxidant flavanoids and arginine, the rate limiting precursor in the biosynthesis of the vasodilatory molecule, nitric oxide. The exact nutrient composition of almonds varies with cultivar [14] and the beneficial effects of almonds may be due to a combination of nutrients.…”

The Inhibitory Mechanisms Study of 5,6,4′-Trihydroxy-7,3′-Dimethoxyflavone against the LPS-Induced Macrophage Inflammatory Responses through the Antioxidant Ability

“…Additionally, high levels of ROS production also leads to the activation of the NF-κB signaling pathway, up-regulation of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) expression and induction of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-α) and interleukins [1][2][3]. Clinically, continuous exposures to oxidative damage have been correlated to cardiovascular diseases, diabetes, chronic inflammation and some types of cancer [4,5]. Therefore, identifying effective blocking agents of ROS production may serve as a potent anti-inflammation and cancer therapeutic.…”