Enhancement of phenolic and flavonoid compounds in cabbage (Brassica oleraceae) following application of commercial seaweed extracts of the brown seaweed (Ascophyllum nodosum)

Brassica crops are rich is phytochemical compounds and frequent consumption of these vegetables has been associated with a lower risk in cancer, heart disease, hypertension and stroke. The effect of three commercial extracts of the brown seaweed, Ascophyllum nodosum, on phytochemical content and yield in cabbage plants was tested under field conditions in two consecutive crops. Total phenolic content was higher in all seaweed treated plants, with the highest increase recorded with AlgaeGreen (TM) (3.5 l ha(-1)) with a 2 fold increase relative to the control. The other commercial seaweed extract, XT achieved a lower increases of 1.3 fold (3.5 l ha(-1)). Similar increases were recorded in total flavonoid content. No statistically significant increases in yield were recorded with any of the seaweed extracts tested. The results suggest that seaweed extracts stimulated an increased accumulation of phytochemicals in cabbage but had no significant effect in yield under these experimental conditions.