Scientific Findings About Organic Agriculture

Flavanol Content Variations in Black Currant Cultivars

Background and methodology:
Flavonoids and related plant compounds in fruits and vegetables are of particular importance because they have been found to possess antioxidant and free-radical scavenging activity. Studies have suggested that a higher intake of flavonoids in food is associated with reduced risks of cancer, heart disease and stroke. The immediate challenge is how to increase the levels of these beneficial phytochemicals in major food plants. The HPLC-based quantitative procedure, with improved extraction and hydrolysis, was used to analyze the content of the flavonols quercetin, myricetin and kaempferol in 10 black currant cultivars from organic farms and in 5 cultivars from conventional farms.

Findings:

Myricetin was the most abundant flavonol, and its amount varied significantly among cultivars, from 8.9 to 24.5 mg/100g (fresh weight). The quercetin levels in black currant also varied widely among the cultivars, from 5.2 to 12.2 mg/100g . The kaempferol levels in black currant cultivars were low, ranging from 0.9 to 2.3 mg/100g. The sum of these major flavonols varied widely among black currant cultivars. No consistent differences in flavonol content of flavonols were found between the same black currant cultivars grown under organic and conventional practices . The high variability in the levels of flavonols in different cultivars offers possible avenues for identifying and selecting cultivars rich in certain flavonols for the production of berries for industrial use.

Reference

Mikkonen, T. P., Maatta, K. R., Hukkanen, A.T., Kokko, H. I., Torronen, A. R., Karenlampi, S. O., and Karjalainen, R. O. (2001). Flavonol content varies among black currant cultivars. Journal of Agricultural and Food Chemistry, 49(7), 3274-3277. Available on-line at: http://pubs.acs.org/doi/full/10.1021/jf0010228.