Marigold Metabolites: Diversity and Separation Methods of Calendula Genus Phytochemicals from 1891 to 2022

Abstract

Marigold (Calendula), an important asteraceous genus, has a history of many centuries of therapeutic use in traditional and officinal medicines all over the world. The scientific study of Calendula metabolites was initiated at the end of the 18th century and has been successfully performed for more than a century. The result is an investigation of five species (i.e., C. officinalis, C. arvensis, C. suffruticosa, C. stellata, and C. tripterocarpa) and the discovery of 656 metabolites (i.e., mono-, sesqui-, di-, and triterpenes, phenols, coumarins, hydroxycinnamates, flavonoids, fatty acids, carbohydrates, etc.), which are discussed in this review. The identified compounds were analyzed by various separation techniques as gas chromatography and liquid chromatography which are summarized here. Thus, the genus Calendula is still a high-demand plant-based medicine and a valuable bioactive agent, and research on it will continue for a long time.

Keywords: Calendula; chromatography; marigold; metabolites; separation methods.

Figure 1

Distribution of studies on plant species from the Calendula genus by year (1891–2022) and an exponential ‘curve of interest’ (blue line). The X-axis is the year, and the Y-axis is the number of publications. The inset shows the impact of each decade on the total publication value.

Figure 2

Sesquiterpenes 176–209. Ac—acetyl; Ang—angeloyl; But—butyl; dCrt—dicrotaloyl; ^βDChip—β-D-chinovopyranose; ^βDFucp—β-D-fucopyranose; iBu—isobutyryl; iVal—isovaleroyl; ^βDGlcp—β-D-glucopyranose; MBu—methylbutenoyl; MPe—methylpentenoyl; MPn—3-methyl-2-pentenoyl; MPr—methylpropanoyl; MSen—4-methylsenecioyl; Sen—senecioyl; Tig—tigloyl.

Figure 3

Lupane derivatives 237–246 and ursane derivatives 247–270.

Figure 4

Oleanane derivatives 271–340. Ac—acetyl; ^βDGalp—β-D-galactopyranose; ^βDGlcp—β-D-glucopyranose; ^βDGlcAp—β-D-glucuronopyranose; Mal—malonyl; Me—methyl.

Figure 4

Oleanane derivatives 271–340. Ac—acetyl; ^βDGalp—β-D-galactopyranose; ^βDGlcp—β-D-glucopyranose; ^βDGlcAp—β-D-glucuronopyranose; Mal—malonyl; Me—methyl.

Figure 5

Phenols 438–443 and benzoic acid derivatives 444–456.

Figure 6

Hydroxycinnamates 457–478. Caf—caffeoyl; pCou—p-coumaroyl; Fer—feruloyl; iFer—isoferuloyl.

Figure 7

Coumarins 479–488. ^βDGlcp—β-D-glucopyranose; ^αLRhap—α-L-rhamnopyranose.

Figure 8

Flavonoids 489–516. Ac—acetyl; ^βDGalp—β-D-galactopyranose; ^βDGlcp—β-D-glucopyranose; ^αLRhap—α-L-rhamnopyranose.