Profiles of Essential Oils and Correlations with Phenolic Acids and Primary Metabolites in Flower Buds of Magnolia heptapeta and Magnolia denudata var. purpurascens

Abstract

Magnolia flower buds are a source of herbal medicines with various active compounds. In this study, differences in the distribution and abundance of major essential oils, phenolic acids, and primary metabolites between white flower buds of Magnolia heptapeta and violet flower buds of Magnolia denudata var. purpurascens were characterised. A multivariate analysis revealed clear separation between the white and violet flower buds with respect to primary and secondary metabolites closely related to metabolic systems. White flower buds contained large amounts of monoterpene hydrocarbons (MH), phenolic acids, aromatic amino acids, and monosaccharides, related to the production of isoprenes, as MH precursors, and the activity of MH synthase. However, concentrations of β-myrcene, a major MH compound, were higher in violet flower buds than in white flower buds, possibly due to higher threonine levels and low acidic conditions induced by comparatively low levels of some organic acids. Moreover, levels of stress-related metabolites, such as oxygenated monoterpenes, proline, and glutamic acid, were higher in violet flower buds than in white flower buds. Our results support the feasibility of metabolic profiling for the identification of phytochemical differences and improve our understanding of the correlated biological pathways for primary and secondary metabolites.

Phytochemical Analysis and Specific Activities of Bark and Flower Extracts from Four Magnolia Plant Species

“…This finding indicates the potential high value of M. champaca and M. grandiflora in applications where elevated levels of phenolic compounds are advantageous, given their abundance in both essential parts of the plant. Comparative studies have identified phenolic acids ranging from 0.018 mg/g dry weight (D.W.) to 4.372 mg/g D.W. in these species [21,24,25]. In the analyzed Magnolia species, compounds such as catechin, myricetin, luteolin, taxifolin, apigenin, and epicatechin are predominantly concentrated in the bark relative to the flowers.…”

Metabolomics Reveals Rubiadin Accumulation and the Effects of Methyl Jasmonate Elicitation in Damnacanthus major Calli

“…The phenolic compounds were extracted and analyzed as described in our previous study, with slight modifications [ 57 , 58 ]. For extracting phenolic compounds, 70 mg of powdered samples was weighed and placed in 2 mL tubes.…”

“…Low-molecular-weight hydrophilic compounds (including amino acids, organic acids, sugars, and sugar alcohols) were extracted and analyzed using our previously reported methods [ 57 , 58 ]. For extraction, 1 mL of a methanol:chloroform:water (2.5:1:1, v / v / v ) solution was added to 15 mg of each sample.…”

Response Surface Methodology in Optimising the Extraction of Polyphenolic Antioxidants from Flower Buds of Magnolia × soulangeana Soul.-Bod. var. ‘Lennei’ and Their Detailed Qualitative and Quantitative Profiling

“…The dried bark and/or flowers of these two species are described in separate monographs of the European Pharmacopoeia as herbal substances standardised for the content of characteristic polyphenolic components, classified as neolignans (magnolol and honokiol) [2] or lignans (magnolin and fargesin derivatives) [3]. In the past two decades, the presence of other compounds belonging to the general group of plant phenolics, especially phenylethanoids [4,5], flavonoids [6] or phenolic acids [7], has also been confirmed in various herbal substances (organs) obtained from magnolia species. All of the aforementioned compounds are characterised by multidirectional biological potential, based mainly on antiradical and antioxidant properties [8].…”

“…They determine antibiodegenerative properties, confirmed by numerous scientific reports, which indicate the protective effect of magnolia extracts or polyphenolic isolates on the function of the nervous [9,10] and cardiovascular [11,12] systems, as well as their broad anti-inflammatory [13] and even anticancer [14][15][16] The dried bark and/or flowers of these two species are described in separate mon of the European Pharmacopoeia as herbal substances standardised for the conten acteristic polyphenolic components, classified as neolignans (magnolol and hon or lignans (magnolin and fargesin derivatives) [3]. In the past two decades, the of other compounds belonging to the general group of plant phenolics, especi nylethanoids [4,5], flavonoids [6] or phenolic acids [7], has also been confirmed in herbal substances (organs) obtained from magnolia species. All of the aforem compounds are characterised by multidirectional biological potential, based m antiradical and antioxidant properties [8].…”