Submitted to: Association for the Advancement of Industrial Crops Conference
Publication Type: Abstract Only
Publication Acceptance Date: 7/26/2007
Publication Date: 10/7/2007
Citation: Morris, J.B., Wang, M.L. 2007. Anthocyanin Content in Leaves and Flowers of Several Hibiscus Species [abstract]. Association for the Advancement of Industrial Crops Conference. p-45.
Technical Abstract: Hibiscus species contain bioactive phytochemicals and nutraceuticals to be utilized in the pharmaceutical and nutraceutical markets. Twenty eight Hibiscus species consisting of more than 300 accessions are conserved at the USDA, ARS, Plant Genetic Resources Conservation Unit, Griffin, GA. Anthocyanins as well as related flavonoid compounds (quercetin and kaempferol) are present in flowers, leaves, calyxes. Anthocyanins are not only responsible for leaf, stem, flower and seed color, but can inhibit LDL oxidation as well as hypertension in humans while the antioxidants, quercetin and kaempferol are known to be anticancer compounds. The objective of this study was to determine the amount of anthocyanin from leaves, flowers, and calyxes of H. brackenridgei, H. calphyllus, H. cannabinus, H. laevis, H. ludwigii, H. radiatus, and H. sabdariffa. An Opti Sciences CCM-200 chlorophyll content meter was converted to an experimental hand-held anthocyanin meter. The manufacturer replaced the 655 nm light emitting diode (LED) of the CCM with a 520 nm LED in order to measure absorbance near the wavelength at which free anthocyanin aglycones, cyaniding and pelargonidin monoglucosides absorb. Anthocyanin indexes will be recorded from each of the three leaves using this modified anthocyanin meter. Preliminary analysis revealed that leaf anthocyanin indexes ranged from 2.9 – 30.5 for H. cannabinus, H. calophyllus, H. laevis, H. ludwigii, H. radiatus, and H. sabdariffa. However, flower anthocyanin indexes from H. cannabinus ranged from 1-167.7. The extremely low anthocyanin indexes (1) were recorded from the white petal portion of the corolla lobes, while the very high anthocyanin indexes (167.7) were recorded from the inner purple and red corolla lobes. The Isoflavones, quercetin and kaempferol have similar biochemical pathways as the anthocyanins, cyanidin and pelargonidin. Hibiscus sabdariffa leaves can produce 280.8 ng/ul of quercetin and 183.4 ng/ul of kaempferol. This indicates that leaf anthocyanins produced in H. sabdariffa include both quercetin and kaempferol. A useful, quantative method employed in the quantification of anthocyanin indexes from different Hibiscus species will be demonstrated. The Hibiscus species identified in this study can serve as potential new sources of high anthocyanins to be introduced into breeding lines or cultivars and/or used as a pharmaceutical or nutraceutical crop in the southeastern U.S.