Two Brassica oleracea varieties (B. oleracea L. var. costata DC and B. oleracea L. var. acephala) and Brassica
rapa L. var. rapa inflorescences were studied for their chemical composition and antioxidant capacity.
Phenolic compounds and organic acids profiles were determined by HPLC–DAD and HPLC–UV, respectively.
B. oleracea var. costata and B. oleracea L. var. acephala inflorescences presented a similar qualitative
phenolic composition, exhibiting several complex kaempferol derivatives and 3-p-coumaroylquinic acid,
while B. rapa var. rapa was characterized by kaempferol and isorhamnetin glycosides and several phenolic
acids derivatives. B. oleracea L. var. costata and B. rapa var. rapa showed the highest phenolics content.
The three Brassica exhibited the same six organic acids (aconitic, citric, pyruvic, malic, shikimic and fumaric
acids), but B. oleracea L. var. acephala presented a considerably higher amount. Each inflorescence was
investigated for its capacity to act as a scavenger of DPPH radical and reactive oxygen species (superoxide
radical, hydroxyl radical and hypochlorous acid), exhibiting antioxidant capacity in a concentration
dependent manner against all radicals. These samples were also studied for its antimicrobial potential
against Gram-positive and Gram-negative bacteria and fungi, displaying antimicrobial capacity only
against Gram-positive bacteria.
