Comparative analysis of petal phytoconstituents reveals insights into the characteristics of an under-reported edible old rose variety native to Chongqing, China

Abstract

Chongqing Old Rose is an ancient edible rose variety native to Chongqing, China, but is under-reported. Further evidence is required to fully establish its potential benefits. The complete metabolic profiles were examined for comparative analysis between the Old Rose and three rose cultivars. The results showed that the pathways of flavonoid biosynthesis, monoterpenoid biosynthesis, and phenylalanine metabolism were significantly enriched in Old Rose. The predominant anthocyanins in Old Rose were cyanidin and peonidin, which may contribute to flower coloration and indicate the antioxidant potential of this plant. Additionally, this plant was rich in aromatic compounds and terpenoids such as 2-phenylethanol, linalool, geraniol, and caryophyllene α-oxide, indicating that it has a natural basis for extracting essential oil. Moreover, the presence of some active phytoconstituents, such as phenols, steroids, and alkaloids, also suggests its potential for edible and medicinal applications besides flavonoids and terpenoids.

Keywords: Edible flower; Floral color; Floral scent; Metabolic pathway; Old rose; Phytoconstituents.

Fig. 1

Flowers of the four roses and the category of the detected phytoconstituents.

Fig. 2

PCA analysis for petals of the four rose varieties. (A) PCA score plot of GC-MS data. (B) Loading plot of GC-MS data. (C) PCA score plot of LC-MS data. (D) Loading plot of LC-MS data.

Fig. 3

Differential metabolites selection between fragrant roses by volcano plots. (A) Volcano plot of differential metabolite in Damascena vs Old Rose based on GC-MS data. (B) Volcano plot of differential metabolites in Crimson Glory vs Old Rose based on GC-MS data. (C) Volcano plot of differential metabolites in Damascena vs Old Rose based on LC-MS data. (D) Volcano plot of differential metabolites in Crimson Glory vs Old Rose based on LC-MS data.

Fig. 4

Differential metabolites selection between fragrant and scentless roses by volcano plots. (A) Volcano plot of differential metabolites in Iceberg vs Damascena based on GC-MS data. (B) Volcano plot of differential metabolites in Iceberg vs Old Rose based on GC-MS data. (C) Volcano plot of differential metabolites in Iceberg vs Crimson Glory based on GC-MS data. (D) Volcano plot of differential metabolites in Iceberg vs Damascena based on LC-MS data. (E) Volcano plot of differential metabolites in Iceberg vs Old Rose based on LC-MS data. (F) Volcano plot of differential metabolites in Iceberg vs Crimson Glory based on LC-MS data.

Fig. 5

Metabolic pathway analysis of the selected differential metabolites. (A) Main metabolic pathways of Old Rose in Old Rose vs Damascena. (B) Main metabolic pathways of Damascena in Old Rose vs Damascena. (C) Main metabolic pathways of Old Rose in Old Rose vs Crimson Glory. (D) Main metabolic pathways of Crimson Glory in Old Rose vs Crimson Glory. (E) Main metabolic pathways of the selected differential metabolites between fragrant and scentless roses.

Fig. 6

Diagram of monoterpenoid biosynthesis and pathway-related compounds. The identified monoterpenoids were mapped to KEGG pathway rcn00902, and the heatmap shows scaled values for relative concentrations. Compounds marked in red: significantly presented in three fragrant roses. Compounds marked in blue: presented in metabolite profiles. Compounds marked in gray: not detected.

Fig. 7

Diagram of phenylalanine metabolism and pathway-related compounds. The identified pathway-related compounds were mapped to KEGG pathway rcn00360, and the heatmap shows scaled values for relative concentrations. Compounds marked in red: significantly presented in three fragrant roses. Compounds marked in blue: presented in metabolite profiles. Compounds marked in gray: not detected.