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Betacyanins extracted from red beets are currently used as food colorants in food industries. In order to produce betacyanins from red beets (Beta vulgaris L.) in in mitro, tissue culture conditions were evaluated and partial characterization of betacyanins extracted from callus was carried out. Callus was induced from hypocotyls of red beet seedlings under a regime of different concentrations of several growth regulators such as NAA, BAP, kinetin, IAA, 2,4-D, and p-CPA on the SH medium. Although a combination of IAA and BAP treatment yielded much higher callus induction frequencies than other treatments, this group resulted in lower callus fresh weight. On the other hand, 0.5㎎/? BAP+3.0㎎/? NAA or 1.5㎎/? BAP with NAA concentration ranging 2.0~4.0㎎/? yielded 100％ callus induction rate. The callus induced by kinetin and IAA developed hairy roots, and the one induced by IAA and BAP had compact structure, while callus induced by BAP and NAA was friable and brittle with very well developed red color. Higher concentrations of IAA and kinetin tended to favor red color accumulation in the red beet callus. On the other hand, no clear tendeny for red color formation was observed in IAA and BAP treatments. In BAP and NAA treatments, intermediate levels of BAP and NAA concentration resulted in a higher red color content in the callus. Red color extracted from callus and beet root showed a identical spectrum in the visible region with ?? at 550nm. The absorption spectra of betacyanins extracted from Beta vulgaris callus were identical between pH 5.0 and 7.0. However, increasing pH from 7.0 to 9.0 caused the ?? to shift to a longer wavelength (?? 537 nm).
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