Background: The properties of natural pigments, such as antioxidants, functional,medical, and nutraceutical, have
demonstrated the advantages of these natural compounds over synthetic ones. Some products are accepted only
when they are pigmented with natural, food-quality colorants: for example poultry products (manly marigold
flower extracts). Carotenoids such as β-carotene, β-criptoxanthin and lutein are very attractive as natural food
colorants due to their antioxidant and pro-vitamin activities which provide additional value to the target
products. Marigold (
Tagetes erecta
) is an Asteraceous ornamental plant native to Mexico, and it is also important
as a carotenoid source for industrial and medicinal purposes but nowadays its production is destined mainly for
ornamental purposes.
Results: Friable callus of
T. erecta yellow flower (YF) and white flower (WF) varieties was induced from leaf
explants on Murashige and Skoog (MS) medium supplemented with 9.0 μM 4-dichlorophenoxyacetic acid
(2,4-D) and 8.8 μM benzyladenine (BA). Calluses developed from both varieties were different in pigmentation.
Extract characterization from callus cultures was carried out by high-performance liquid chromatography
(HPLC). This analytical process detected several carotenoids; the main pigments in extracts from YF callus
were lutein and zeaxanthin, whereas in the extracts of the WF callus the main pigmentswere lutein, zeaxanthin,
β-cryptoxanthin and β-carotene. Callus cultures of
T. erecta accumulated pigments even after several rounds of
subculture.
Conclusions: WF callus appeared to be a suitable candidate as a source of different carotenoids, and tested varieties
could represent an alternative for further studies about in vitro pigment production.