Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/25/1996
Publication Date: N/A
Technical Abstract: It has been difficult to carefully examine the bioregulation of flavonoid accumulation in citrus species due to a lack of good model system. Most established cell lines derived from Citrus do not accumulate flavonoids. However, a ten-year old callus culture line originally established from the embryonic tissues of Mexican lime (Citrus aurantifolia Swing.) has been shown to actively accumulate flavonoids in culture, especially kaempferol glycosides. Several plant bioregulatory compounds were evaluated for their effect on flavonoid accumulation in this callus system. Abscisic acid, naphthalene acetic acid, zeatin and gibberellic acid all increased the accumulation of the callus flavonoids. We also found that the addition of a crude oligosaccharide fraction prepared from mechanically-wounded citrus leaves induced the formation of new flavonoids in both the Mexican lime callus and in Marsh grapefruit callus which does not normally accumulate flavonoids. From these model studies, it may be possible to develop simple protocols for the biomodulation of flavonoid accumulation in developing plants and fruits. As an example of this method development, Gibberellic acid applied in lanolin pastes or as sprays has been shown to be an effective modulator of naringin levels in developing grapefruit.