Analysis of aroma-active compounds in three sweet osmanthus (Osmanthus fragrans) cultivars by GC-olfactometry and GC-MS

Abstract

Abstract:Objective: Aroma is the core factor in aromatherapy. Sensory evaluation of aromas differed among three sweet osmanthus (Osmanthus fragrans) cultivar groups. The purpose of this study was to investigate the aroma-active compounds responsible for these differences. Methods: Gas chromatography-olfactometry (GC-O) and GC-mass spectrometry (GC-MS) were used to analyze the aroma-active compounds and volatiles of creamy-white ('Houban Yingui', HBYG), yellow ('Liuye Jingui', LYJG), and orange ('Gecheng Dangui', GCDG) cultivars. Results: Seventeen aroma-active compounds were detected among 54 volatiles. trans-β-Ocimene, trans-β-ionone, and linalool, which were major volatiles, were identified as aroma-active, while cis-3-hexenyl butanoate, γ-terpinene, and hexyl butanoate were also aroma-active compounds, although their contents were low. Analysis of the odors was based on the sum of the modified frequency (MF) values of aroma-active compounds in different odor groups. HBYG contained more herb odors, contributed by cis-β-ocimene and trans-β-ocimene, while LYJG had more woody/violet/fruity odors released by trans-β-ionone, α-ionone, and hexyl butanoate. In GCDG, the more floral odors were the result of cis-linalool oxide, trans-linalool oxide, and linalool. Conclusions: Aroma-active compounds were not necessarily only the major volatiles: some volatiles with low content also contributed to aroma. The aroma differences among the three cultivars resulted from variation in the content of different odor groups and in the intensities of aroma-active compounds.

Floral volatiles identification and molecular differentiation of Osmanthus fragrans by neutral desorption extractive atmospheric pressure chemical ionization mass spectrometry

“…The peaks at m/z 155.1428 (C 10 H 19 O + ), m/z 153.1276 (C 10 H 19 O + ), m/z 143.1064 (C 8 H 15 O 2 + ), and m/z 83.0489 (C 5 H 7 O + ) are attributed, respectively, to protonated linalool, hotrienol, 3‐hexenyl acetate, and 2‐methylfuran, which were found in all the cultivars except for “ziyinggui”. Upon CID, protonated linalool generated major product ions at m/z 137, 127, 113, 109, 99, 95, and 85 (Figure S6B, supporting information), by loss of H 2 O, CH 2 =CH 2 , CH 3 ‐CH=CH 2 , H 2 O + CH 2 =CH 2 , C 4 H 8 , CH 3 ‐CH=CH 2 + H 2 O, and C 5 H 10 , respectively, in accordance with the ions detected from authentic linalool (Figure S6A, supporting information); the detailed fragmentation mechanism is depicted in Figure S7 (supporting information).…”

“…Fourteen of the identified VOCs were terpenoids. Nine of the reported VOCs, 3‐buten‐2‐one, cyclohexadiene, 2‐methylfuran, 3‐allylcyclohexene, cuminyl alcohol, hotrienol oxide, epoxy‐linalol oxide, N ‐(2‐hydroxyethyl) octanamide, and 3‐hydroxy‐dihydro‐β‐ionone, have not been identified in O. fragrans flowers in previous GC/MS studies . The identities of these nine new chemicals were tentatively assigned based on their exact masses, collision‐induced dissociation (CID) product ion spectra, and literature MS search for the VOCs reported from other plant flowers …”

“…Based on earlier literature reports, this peak was tentatively assigned to protonated 3‐hydroxydihydro‐β‐ionone, which has not been previously reported in O. fragrans flowers. From a previous study of the constituents in O. fragrans flowers, the peak at m/z 169.1220 (C 10 H 17 O 2 + ) was assigned to protonated hotrienol oxide (Figure S5, supporting information). Based on previous reports, the minor shared peaks at m/z 177.1634 (C 13 H 21 + ) and m/z 188.1642 (C 10 H 22 NO 2 + ) were assigned to protonated 1,4‐diisopropyl‐2‐methylbenzene and N ‐(2‐hydroxyethyl) octanamide, respectively, with these assignments being supported by their high‐resolution and CID data (Table ).…”

Investigation of the chemical markers for experiential quality evaluation of crude aconite by UHPLC–Q‐TOF‐MS

“…Many foods and herbs are often classified into several commodity grades in market transactions, and different grade ones are considered to be of diverse quality. These classifications are mainly dependent on some sensory indicators, including color , smell , flavor , size , and weight . Although this method is simple and easy to implement, it is still relatively primitive.…”

Cloning and Expression Analysis of MEP Pathway Enzyme-encoding Genes in Osmanthus fragrans

“…Generally, the cultivars in the Luteus group have golden-yellow flowers that only appear in the fall, whereas the Asiaticus group cultivars bloom all year round and have creamy-yellow flowers [5]. The fresh flowers are very abundant in aromatic compounds, including terpenoids, fatty acid derivatives, and phenylpropanoids/benzenoids [6,7]. Although the relative contents of the volatiles vary among different cultivars and developmental stages, the main aromatic components are the terpenoids, including monoterpenes ocimene and linalool [8,9,10].…”