Broccoli seed extracts but not sulforaphane have strong free radical scavenging activities

Abstract

The abilities of broccoli seed extracts and purified sulforaphane (SF) to scavenge 2,2 0 -azinobis [3-ethylbenzothiazoline-6-sulphonate] (ABTS •+ ), 2,2-diphenyl-1-picrylhydrazyl (DPPH • ) and superoxide anions were studied. The free radical scavenging activities of broccoli seed extracts had no exact correlation with SF content, indicating that SF was not the main antioxidant component. The broccoli seed extracts were separated by high-speed countercurrent chromatography to obtain purified SF, which showed dosedependent free radical scavenging activities in the DPPH • and ABTS •+ assays, but its activities were weaker to those of ascorbic acid. The same trend was observed in the chemiluminescence assay. The results showed that broccoli seed extracts had strong free radical scavenging activities that were not attributable to SF.

<i>In Vitro</i> Analyses of Antioxidant Activity of Food Supplements GE Kids<SUP>®</SUP> and GE 132+ Natural<SUP>®</SUP>

“…The similar results were found in the case of curcumin extract, constituent of GE kids ® [24], as well as for broccoli seed extracts, ingredient of GE 132+ natural ® which represents the source of sulforaphane [25]. Interestingly, broccoli seed extracts showed strong free radical scavenging activities, but sulforaphane itself showed much lower activity, indicating that this isothiocyanate is not the main contributor to the radical scavenging capacity of broccoli [25]. This highlights the importance of the synergistic effects of the antioxidant components from various natural products.…”

“…Besides extract of Ganoderma lucidum, resveratrol, a component also present in both supplements, was previously shown to have anti-ABTS· + and anti-DPPH· activity [23]. The similar results were found in the case of curcumin extract, constituent of GE kids ® [24], as well as for broccoli seed extracts, ingredient of GE 132+ natural ® which represents the source of sulforaphane [25]. Interestingly, broccoli seed extracts showed strong free radical scavenging activities, but sulforaphane itself showed much lower activity, indicating that this isothiocyanate is not the main contributor to the radical scavenging capacity of broccoli [25].…”

Untargeted polysulfide omics analysis of alternations in polysulfide production during the germination of broccoli sprouts

“…SFN is known to function as a potent inducer of Phase II detoxification enzymes such as NAD(P)H:quinone oxidoreductase 1 and glutathione S -transferase by activating the Keap1/Nrf2 pathway [ 55 ]. Moreover, SFN can directly scavenge radicals; however, a recent study that employed the DPPH radical-scavenging assay reported that the radical-scavenging capacity of SFN was remarkably weaker than that of ascorbic acid [ 56 ]. The free radical– scavenging activities of broccoli seed extracts did not correlate with the SFN content of the seeds, indicating that SFN is not the primary antioxidant component of broccoli seeds [ 56 ].…”

“…Moreover, SFN can directly scavenge radicals; however, a recent study that employed the DPPH radical-scavenging assay reported that the radical-scavenging capacity of SFN was remarkably weaker than that of ascorbic acid [ 56 ]. The free radical– scavenging activities of broccoli seed extracts did not correlate with the SFN content of the seeds, indicating that SFN is not the primary antioxidant component of broccoli seeds [ 56 ]. In contrast, it has been demonstrated that GS2H has a greater H 2 O 2 -scavenging capacity than GSH [ 9 ].…”

Antioxidant and anti‐tyrosinase activity of a novel stilbene analogue as an anti‐browning agent

“…The assay of scavenging the was adopted from a previous report, with minor modifications 21 . Tris–HCl buffer (2 mL, 0.1 mmol L –1 , pH 8.0) was mixed with sample solution at different concentrations (2 mL; 1.01, 2.02, 4.04, 8.08, 12.12, 16.16 and 20.20 mmol L –1 ); then, a pyrogallol solution (1 mL, 5 mmol L –1 ) pre‐incubated at 25 °C was added.…”