HPLC study on the carotenoid composition of Calendula products

Potential of NIR‐FT‐Raman spectroscopy in natural carotenoid analysis

“…On the basis of HPLC investigations it is known that petals and pollen of marigold (Calendula officinalis L.) contain mostly flavoxanthin and luteoxanthin (see Figure 1). 45 Luteoxanthin is formed from violaxanthin in the process of epoxidefuranoxide rearrangement, resulting in shortening of the chain to 8 conjugated double bonds. Further epoxidation results in the formation of auroxanthin with a 7-conjugated chain.…”

“…1 Auroxanthin is present in marigold petals in high amounts whereas, in the pollen, lutein and antheraxanthin (both pigments are 9-conjugated carotenoids) are additionally detected. 45 The spectra presented in Figure 7A are taken from marigold flower; they show the different location of the carotenoid v 1 bonds. The stretching vibration of CϭC bonds of the diepoxycarotenoid auroxanthin is observed at 1536 cm Ϫ1 , exactly at the same wavenumber as for crocetin, the other 7-conjugated system ( Figure 7A, upper spectrum).…”

“…The distribution of lutein and antheraxanthin is opposite, which is in agreement with the performed HPLC measurements ( Figure 7E). 45 The derived luteoxanthin with 8-conjugated bonds can be allocated to all flower parts ( Figure 7D). However, it is important to stress that the Raman mapping results show the concentration of carotenoids both at the surface and in the surface layer of the flower.…”

Studies on Carotenoids in the Petals of Compositae Plants

“…3), three geometrical isomers of lutein (the all-E form and two mono-Z forms), and two epimeric lutein-5,8-epoxides. Recent researchas revealed that various cis-form carotenoids occur in petals (Deli et al, 1988;Kull and Pfander, 1995;MelendezMartinez et al, 2006;Molnár et al, 1986); however, the di-Z forms of cyclized carotenoids are particularly rare molecular structures and have been reported as natural products only in the petals of rape (Brassica napus L.) ((9Z,9'Z)-lutein; Kull and Pfander, 1997), calendula (Calendula officinalis L.) ((9Z,9'Z)-lutein and (13Z,13'Z)-lutein; Bakó et al, 2002), African marigold ((13Z,13'Z)-lutein; Khachik et al, 1999), and pansy (Viola × wittrockiana Gams) ((9Z,9'Z)-violaxanthin, (9Z,13Z)-violaxanthin, (9Z,13'Z)-violaxanthin, and (9Z,15Z)-violaxanthin; Molnár et al, 1986). The function of these carotenoids in petals is still unknown.…”

“…7). Some carotenoids have been characterized by TLC and HPLC (Bakó et al, 2002;Tóth and Szabolcs, 1981), but their precise molecular structures had not been determined and several unknown components remained to be elucidated.…”