Study on the Quality and Composition Changes of Cinnamon from Different Origins and Processing Processes
Cinnamon is the dried bark of the Cinnamomum cassia Presl plant in the Lauraceae family. It is often peeled in spring and autumn and dried in the shade. It was first recorded in the “Shennong Bencao Jing” and is a widely used medicinal and edible herb in China. It has the effects of “tonifying fire and promoting yang, igniting fire and returning to the yuan, dispersing cold and relieving pain, and warming the meridians”. Modern pharmacological research has shown that cinnamon has various pharmacological effects such as lowering blood sugar, lowering blood lipids, anti-tumor, antioxidant, antibacterial, antiviral, reducing gastric damage, and improving learning and memory abilities; Cinnamon contains various components such as volatile oil, flavonoids, sesquiterpenes, and polysaccharides, among which volatile components are its main active ingredients; As a traditional Chinese medicine with a cooling effect, cinnamon can also activate brown adipose tissue and significantly increase non shivering thermogenesis by upregulating the expression of thermogenic proteins.
The processing method of cinnamon is to remove impurities and rough skin. The “Lei Gong Pao Zhi Lun”, “Ben Cao Jing Ji Zhu”, and “Tai Ping Sheng Hui Fang” clarify the methods of removing rough skin, peeling off weak armor, and removing wrinkled skin. The “Tai Ping Hui Min He Zhi Ju Fang” states that “peeling without seeing fire” and that whether cinnamon is peeled or not depends on its effectiveness. The efficacy of cinnamon before and after removing the rough skin is often related to its chemical composition. This article mainly focuses on cinnamon from Yangchun, Yunfu, Zhaoqing in Guangdong, Fangchenggang, and Guigang in Guangxi as the research objects. By evaluating the origin of cinnamon raw materials through multiple indicators of composition, and analyzing the changes in composition during the processing of cinnamon from different origins, it can provide reference for research work such as cinnamon origin selection and quality evaluation.

 

This study collected 28 batches of cinnamon samples from 7 counties/cities in Guangdong and Guangxi, and established fingerprint spectra of cinnamon samples using UPLC method. The similarity between each batch of cinnamon samples and the control spectrum was 0.996 or above, indicating good similarity. The established fingerprint spectra can be used to evaluate the quality of cinnamon. Using Origin Pro 2023 software, cluster analysis and principal component analysis were conducted on 28 batches of cinnamon with 10 common peak areas as variables. Cluster analysis showed that the samples could be divided into three categories. Among them, samples from Yangchun, Guangdong, Gaoyao District, Zhaoqing City, Fangchenggang, and Guigang in Guangxi were relatively concentrated in classification, while samples from Yunfu City, Guangdong and Deqing County in Zhaoqing City were relatively scattered. The 10 common peaks were divided into four categories: coumarin and 2-methoxycinnamaldehyde were clustered together, cinnamic acid, cinnamaldehyde, cinnamic alcohol, cinnamic acid, and cinnamic acid were clustered together, peaks 2-5 were clustered together, and peak 1 was clustered together. There was a certain correlation between raw material classification and peak classification. Cinnamon raw materials from different origins have certain differences, which can be analyzed by Distinguish based on chemical composition; Principal component analysis identified four principal components. The information of the first principal component mainly comes from peaks 2-5, the information of the second principal component mainly comes from cinnamic alcohol, cinnamic acid, and cinnamaldehyde, the information of the third principal component mainly comes from coumarin and 2-methoxycinnamaldehyde, and the information of the fourth principal component (PC4) mainly comes from peak 1. The score map shows that the distribution of samples from Fangchenggang, Guigang, Yangchun, Guangdong, and some Zhaoqing in Guangxi is relatively concentrated, while the distribution of samples from Yunfu and some Zhaoqing is relatively scattered. However, the distribution of each origin still has certain patterns, and the information sources and score map results of each principal component are similar to those of cluster analysis. At the same time, OPLS-DA analysis was conducted on 10 common peak variables using SIMCA14.1 software, which can effectively distinguish cinnamon from Guangdong and Guangxi provinces. Five components with significant contributions to the production area were selected (coumarin, peak 3, peak 5, 2-methoxycinnamaldehyde, and peak 2), and the differences in components may be related to different planting environments in the production area. And based on the peak area, the content of coumarin, 2-methoxycinnamaldehyde, cinnamyl alcohol, cinnamic acid, and cinnamaldehyde in cinnamon was determined by UPLC.
The results of content and volatile oil determination showed that the average content of the five components and volatile oils of cinnamon before and after processing were relatively similar. The reason for cinnamon’s “peeling without fire” was low correlation with phenolic components such as cinnamaldehyde and volatile oils; And the overall trend of changes in cinnamaldehyde, cinnamic acid, and cinnamyl alcohol between batches is similar, as well as the trend of changes in 2-methoxycinnamaldehyde and coumarin, which is consistent with the classification results of the common peaks in the previous period.
In summary, this study established a UPLC fingerprint method for cinnamon, analyzed the medicinal materials and common peaks from various origins using chemical stoichiometry, established content determination methods for five components, and compared the differences in components before and after processing of the medicinal materials, in order to provide reference for the selection of the origin and quality research of cinnamon medicinal materials.