In vitro: |
Natural Product Research, 2007, 21(8):726-732. | Antioxidant hydroxycinnamic acid derivatives isolated from Brazilian bee pollen.[Pubmed: 17616901] | One novel and three known hydroxycinnamic acid derivatives having antioxidant activities were isolated from a Brazilian bee pollen. They were identified as kaempferol 3-O-[2-O-p-coumaroyl]-α-L-arabinopyranoside, N1,N5,N10-tri-p-coumaroyl spermidine(N1,N5,N10-(E)-tri-p-coumaroylspermidine), N1,N5,N10,N14-tetra-p-coumaroyl spermine, and monocaffeoyl-tri-p-coumaroyl spermine, respectively. The structure of the kaempferol glycoside was established on the basis of spectroscopic and chemical investigations.
CONCLUSIONS:
Among the isolated compounds, monocaffeoyl-tri-p-coumaroyl spermine showed the strongest free radical-scavenging activity, which was almost identical to that of α-tocopherol. On the other hand, the antioxidant effect of tri-p-coumaroyl spermidine on autooxidation of linoleic acid was strongest and nearly equal to that of α-tocopherol. |
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