Cinnamomum loureirii is one of the most important medicinal and aromatic plants. It is used by the food, perfumery, cosmetic, and pharmaceutical industries. The objective of this study was to examine the relationships between the chemical composition and antioxidant activity of essential oil (EOs) and ethanol extracts from 10 samples of the bark from C. loureirii trees (6–15 years old). Obtained results showed that C. loureirii bark EO content at 12–15 years old had high oil yields (4.52–5.48%). The major components in the EOs were trans-cinnamaldehyde (50.2–92.9%) and α-copaene (0.5–21.3%). The highest content of trans-cinnamaldehyde in bark EOs was obtained from 10 to 12-year-old trees, while the highest content of α-copaene was obtained at 13–15 years. The highest total phenolic (429.85 and 474.45 mg TAE /g DW) and total flavonoid contents (85.54 and 102.80 mg RE /g e DW) were obtained from the 13- to 14-year-old trees. Our results indicated that the EO and ethanol extract of 13- to 14-year-old bark showed the strongest antioxidant properties. Moreover, GC–MS, PCA and correlation analysis indicated that the changes in α-copaene, beta-caryophyllene, τ-muurolene, γ-muurolene, δ-cadinene and τ-muurolol were positively correlated with the changes in antioxidant activity in oils. Meanwhile, procyanidin B2 and hyperoside were the main contributors to the antioxidant activity of the ethanol extract from C. loureirii bark. This study is the first one that report the antioxidant potential and phenolic profile of C. loureirii plant. These results provide reference information for the rational utilization of C. loureirii resources and the harvest of C. loureirii bark as medicinal materials during the optimal period.

The cinnamon leaf is widely used in flavoring, cooking, essences and medicine. In this work, we systematically detected and identified the volatile compounds of the leaves from five cinnamon species ( Cinnamomum cassia (Xijiang type), C. cassia (Fangcheng type), C. loureirii , C. verum and C. burmannii ) collected in China by using the methods of GC–MS and FTIR analysis, and compared the correlation between the density of oil cells and the yields of essential oils among above detected samples. The results indicated that the variation of the yields of essential oils was significant positively correlated with the density oil cells of five cinnamon leaves. Based on the results of GC–MS, trans-cinnamaldehyde was the primary components in the four cinnamon species except for C. verum. Notably, the highest contents of trans-cinnamaldehyde in the essential oil are C. loureirii (72.49%), followed by C. cassia (Xijiang type) (60.65%). Eugenol (83.26%) was the main substance of C. verum leaves. In addition to trans-cinnamaldehyde, isoamyl benzoate (7.02%) and α-thujene (6.28%) were the main volatile compounds in C. burmannii leaves. Finally, through analyzing the FTIR data by using hierarchical cluster and similarity analysis were further revealed that the chemical compositions of essential oil were similar of C. loureirii , C. cassia (Xijiang type) and C. cassia (Fangcheng type), and they were significantly different from C. verum and C. burmannii . All these results confirm that species and cultivated environment can lead to the changes in essential oil composition.

The twigs of cinnamon plants are widely used in traditional Chinese medicine in the treatment of tumors, hypertension, abdominal pain, dysmenorrhea, digestive system disease, and inflammatory processes. The aim of this study was to evaluate the volatile compounds of cinnamon twigs from three species and eleven habitats based on gas chromatography–mass spectrometry and attenuated total reflection Fourier transform infrared analysis. The results showed that cinnamon twigs from Cinnamomum loureiroi Nees, Lauraceae, had a high volatile oil yield (1.49%) with a high percentage of trans-cinnamaldehyde (75.45%). The cinnamon twigs from C. verum J.Presl contained high contents of eugenol (4.42%), except for trans-cinnamaldehyde (57.25%). The contents of oil and trans-cinnamaldehyde in C. cassia (L.) J.Presl twigs varied among habitats from 0.74–2.18% and 65.27–74.56%, respectively. Additionally, the trans-cinnamaldehyde content of C. cassia twigs from Guangxi (70.32–74.56%) was higher than that of C. cassia twigs from Guangdong (65.27–68.69%). Hierarchical cluster analysis showed that thirteen samples were divided into three dominant classes. Sample B (C. verum) was distinguished as a single cluster because it had a high content of eugenol. Our work indicated that chemometrics, in combination with gas chromatography and Fourier transform infrared, proved to be effective for identifying species, determining their geographical distribution, and controlling the quality of cinnamon twigs.