Cempoalxóchitl: A Plant of the Day of the Dead

The cempasúchil flower is native to Mexico, its name comes from the Nahuatl "Cempohualxochitl" which means: Flower of 20 petals. During the pre-Hispanic era, the Mexicas assimilated the yellow color of this flower with the sun, therefore, they used it in altars, offerings, and burials dedicated to their dead.

In Mexico, the cempasúchil flower is located wild in the states of Chiapas, Jalisco, Puebla, San Luis Potosi, Mexico, Oaxaca, and Veracruz; it was domesticated by different indigenous groups before the arrival of the Spaniards to America. For example, the Aztecs cultivated it for ceremonial and medicinal purposes and other cultures gave it diverse uses.

What do you think of when you hear the word cempoalxóchitl?

Surely in that intense orange flower, with a characteristic aroma that transports you to the Day of the Dead, which in Mexico is celebrated on November 1 and 2. Most of the time we associate this plant with its ornamental use or in religious ceremonies, so it is difficult to relate it with something else, for example, with the food industry.

Cempoalxóchitl has a long history throughout domestication to which it has been subjected. Domestication is a process of artificial selection by which a wild species is modified by acquiring certain heritable traits to obtain certain benefits for humans.

Currently, six centers of plant domestication are recognized in the world, defined since 1935 by Nikolai Vavilov, and Mexico is part of the Mesoamerican center of origin and diversification of plants such as corn, beans, avocado, chili, and of course, cempoalxóchitl, just to mention a few. Several authors agree that the center of origin of cempoalxóchitl is Mexico, where it has the greatest diversity and can be found both wild and cultivated.

The domestication process of cempoalxóchitl dates back to pre-Hispanic times when the Nahua people had specialists in charge of domesticating, improving, and cultivating species according to their interests. One of them was the search for more beautiful flowers, given the selection of characters to obtain more showy flowers, more intense colors, and aroma.

What do we call cempoalxóchitl?

The Nahuatl group used this name to refer to the variety of plants with characteristics such as green leaves and stems in different shades, very aromatic, with petal heads showy for their colors, among which orange, yellow, and red and their combinations stood out.

This set of characteristics is conferred to the genus Tagetes, family Asteraceae, endemic to the American continent. Therefore, the Nahuatl came to identify different species and varieties of Tagetes. At present, a total of 58 species have been recorded throughout the American continent, of which between 33 and 35 are found in Mexico.

Which species known to the Nahuatl were called cempoalxóchitl?

The General History of New Spain by Fray Bernandino de Sahagún represents one of the first documents that provide ethnobotanical information about the genus Tagetes (Florentine Codex, 1577), as well as the work Natural History of New Spain by the proto-medic Francisco Hernández (1570). In the Florentine Codex of Fray Bernandino de Sahagún, illustrations of the species of the genus Tagetes are presented and some of its characteristics (color, smell, sex of the plant) are described.

While in the work of Francisco Hernandez, goes into more detail about the species and establishes the differences by the Nahuatl name, color, and size. Both works mention the existence of the wild and cultivated conditions of the cempoalxóchitl plants, indicating that, on the one hand, sowing was practiced and on the other hand, harvesting.

From the Florentine Codex, with botanical studies carried out in Mexico, the species Tagetes erecta L. and Tagetes lunulata Ort. are indicated as cempoalxóchitl. However, the cultivated species also correspond to T. erecta and T. patula, while the wild collection species may be T. erecta silvestre, T. lunulata, and T. tenuifolia, respectively.

Distribution of cempoalxóchitl

Tagetes can be found throughout Mexico; however, not all species are distributed uniformly, as a greater concentration of species has been observed in the center-south of the country due to the intersection of the most important mountain ranges of Mexico: Sierras Madre Occidental, Oriental and del Sur and Eje Neovolcánico, combining different climates, soils, geology, relief, and environmental diversity. This diversity of habitat predisposes a wide morphological variability that is observed in the characteristics described for Tagetes species. This has been observed in the maps made of the distribution of 33 Tagetes species.

Importance of the genus Tagetes

The main characteristics of the species of this genus are the pigmentation and diversity of shades of their flowers, given by chemical compounds called carotenoids. This property has given some species not only an ornamental attraction but also a place in the food industry. Secondary metabolites (chemical compounds) have been developed throughout the plant, mainly related to traditional medicine and biocides.

Carotenoids are pigments found naturally in many organisms. Their main biological function is to serve as pigments in the absorption and collection of light in photosynthesis, and they are responsible for the vast majority of orange, red, and yellow colors. They are divided into two large groups: carotenes and xanthophylls. The difference lies in the fact that the latter contains at least one oxygen atom in its chemical structure. The most important carotene in plants is β-carotene and the main carotene in xanthophylls is lutein.

Cultural uses and sources of bioactive compounds

The cempoalxóchitl is strongly related to ceremonial practices referred to pre-Hispanic times. Today, the ceremonial use of the dead continues; however, the meaning differs from that of pre-Hispanic times. Also, currently, several of the Tagetes species used in Mexico are used, due to their characteristic properties (color and aroma) within the framework of traditional medicine, as curative for physical and supernatural diseases.

However, the greatest potential of cempoalxóchitl has been attributed to its biological functions and actions. Therefore, the interest in carotenoids is no longer only for their usefulness as ornamentation, but for their biological properties, since the study of these in the prevention of diseases has proven to be a very broad field and of great importance for its role as a nutraceutical agent, as is the activity of provitamin A of carotenoids.

Countries such as China, India, and Peru have sought to modify through hybridization (crossing of two varieties or two different species) and genetic selection, better varieties to obtain superior pigments; contrary to what one would think, Mexico is not the first producer of Tagetes for its use as a source of bioactive compounds.

Why is it that Mexico is not among the main countries in terms of the production and research of this species?

During the year 2000, there was an increase in the production of cempoalxóchitl, planting around four thousand hectares destined for the pharmaceutical and food industry. However, the pharmaceutical company to which much of the production was destined was sold to Indian investors, causing production to decrease.

Despite the great cultural importance of cempoalxochitl as a source of compounds, due to the lack of support in scientific research and the transfer of production to foreign hands, its study has been neglected and has prevented Mexico from competing in the market of plant pigments.

However, efforts have been made to obtain a higher content of xanthophylls in T. erecta, so in 2008 the Cempoalxóchitl Network was created (reactivated in 2020) to coordinate the participation of researchers, companies, farmers, and the general public, interested in working with plants of the genus Tagetes in areas of in situ and ex situ conservation and resource enhancement.

Mexico has a great advantage in possessing the greatest biodiversity of this species -both morphological and genetic- within its territory, as well as for its planting and growing conditions. However, the true potential of most Tagetes species is unknown due to their scarce study, hence the need for research aimed at increasing the cultivation of cempoalxochitl for cultural and ornamental use and as a source of compounds to compete in the foreign market. As we have seen, the cempoalxochitl has had a great historical trajectory in Mexico, therefore it is important to deepen its study for its conservation and to potentiate this resource.

Written by Kenia Elizabeth Ortega Jiménez and Johnattan Hernández Cumplido, Source: Saber Más Magazine publishes popular science articles in a digital (web) format.