Tronchuda cabbage (Brassica oleracea L. var. costata DC) seeds: Phytochemical characterization and antioxidant potential

Abstract

Tronchuda cabbage (Brassica oleracea L. var. costata DC) seeds were studied for their chemical composition and antioxidant capacity. Thirteen phenolic compounds were characterized and quantified by reversed-phase HPLC-DAD-MS/MS-ESI and HPLC-DAD, respectively: two sinapoylgentiobiose isomers, three sinapoylglucose isomers, kaempferol-3-(sinapoyl)sophorotrioside-7-glucoside, sinapoylcholine, kaempferol-3,7-diglucoside-4 0 -(sinapoyl)glucoside, three disinapoylgentiobiose isomers, 1,2,2 0 -trisinapoylgentiobiose and 1,2-disinapoylglucose. Seven organic acids (aconitic, citric, ascorbic, malic, quinic, shikimic and fumaric acids) were also identified and quantified by HPLC-UV. The aqueous extract of tronchuda cabbage seeds was investigated for its capacity to act as a scavenger of DPPH Å radical and reactive oxygen species (superoxide radical, hydroxyl radical and hypochlorous acid), exhibiting antioxidant capacity in a concentration-dependent manner against all radicals. These results may be attributed to the high content of hydroxycinnamic derivatives and ascorbic acid.

Application of ultra performance liquid chromatography-photodiode detector-quadrupole/time of flight-mass spectrometry (UPLC-PDA-Q/TOF-MS) method for the characterization of phenolic compounds of Lepidium sativum L. sprouts

“…Next, dihexoside moiety (2 9 162 amu = 324 amu) is lost which gives rise to a deprotonated kaempferol ion (m/z 285.0403) as a base peak. This kind of fragmentation indicates the occurrence of glycosylation in accordance with literature data which show that in Brassica species, only sugar moieties such as glucose and rhamnose are predominantly bound in positions -7 [19,32,33,35,36]. In the disaccharide moieties present in analyzed compounds [2,3,5, and 6 (Table 1)] after fragmentation, the loss of 324 amu and low abundance of 162 amu selon occur, which, according to Ferreres et al [31], corresponds to a diglucoside with a 1-6 linkage, that is, gentiobioside.…”

Screening of Antioxidant Compounds During Sprouting of Brassica oleracea L. var. costata DC

“…costata sprouts was monitored during 12 days of germination. The HLPC/DAD analysis showed the presence of 12 phenolic compounds already identified in the seeds of B. oleracea, at all germination times [20]. These compounds include five sinapoyl glucosides, four disinapoyl glucosides, one trisinapoyl glucoside, sinapoyl choline, and one kaempferol glucoside acylated with sinapic acid (Figs.…”

“…The analysis of phenolic compounds was carried out as reported previously [20] using HPLC (Gilson) and a RP-18 LiChroCART (Merck, Darmstadt, Germany) column (250 x 4 mm, 5 μm particle size), protected with a 4 x 4 mm LiChroCART guard column. Elution was performed using acetic acid 1% (A) and methanol (B) as solvents, starting with 20% B and using a gradient to obtain 50% B at 30 min and 80% B at 37 min.…”

“…The major phenolic compounds found in Brassica seeds are esterified phenolic acids [20]. Phenolic choline esters are characteristic and may contribute to the bitter taste and astringency of seed products.…”

“…Sinapine, the choline ester of sinapic acid, is the most abundant one in seeds of the Brassicaceae family, being considered a major anti-nutritive com-pound [2,21]. The results obtained with B. oleracea seed extract showed that phenolics and organic acids in seeds were important as antioxidants [20]. This antioxidant potential can be especially important during germination, when oxygen demand is high [16].…”