TITLE:
Difference of Curcumin Content in Curcuma longa L. (Zingiberaceae) Caused by Hybridization with Other Curcuma Species
AUTHORS:
Hiroshi Hayakawa, Yukio Minaniya, Katsura Ito, Yoshinori Yamamoto, Tatsuya Fukuda
KEYWORDS:
Curcuma longa, Curcumin, Hybridization, Introgression, Molecular analysis, Nuclear DNA
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.2 No.2,
July
1,
2011
ABSTRACT: Curcumin, which is traditionally known to have effects on various types of diseases in humans, is found in Curcuma longa L. Previous reports have indicated that the curcumin content varies between the different lines of this species. To clarify the differences in the amounts of curcumin between the lines, we investigated the outcomes of cultivation ex-periments with the hybridization or introgression between C. longa and other Curcuma species using the matK gene of chloroplast DNA (cpDNA) and the external transcribed spacer (ETS) of nuclear DNA (nrDNA). The results show that there is heterogeneity of the ETS and incongruence between the matK and the ETS phylogenetic trees, suggesting that hybridization and introgression had taken place in the diversification of the various lines of C. longa. Moreover, al-though all of the lines had the same cpDNA haplotype of C. longa, the lines of homogeneous C. longa had a high con-tent of curcumin, whereas the lines created by hybridization and introgression with other Curcuma species had a me-dium or low level. These results suggest that the difference of curcumin content among the various lines of C. longa was caused by hybridization and introgression with other Curcuma species.