Chemical characterization and quality assessment of copaiba oil-resin using GS/MS and SFC/MS

Authors: LEE, JOSEPH - University Of Mississippi; Wang, Mei; ZHAO, JIANPING - University Of Mississippi; ALI, ZULFIQAR - University Of Mississippi; HAWWAL, MOHAMMED - University Of Mississippi; KHAN, IKHLAS - University Of Mississippi

Submitted to: Plants
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/3/2023
Publication Date: 4/11/2023
Citation: Lee, J., Wang, M., Zhao, J., Ali, Z., Hawwal, M., Khan, I. 2023. Chemical characterization and quality assessment of copaiba oil-resin using GS/MS and SFC/MS. Plants. https://doi.org/10.3390/plants12081619.
DOI: https://doi.org/10.3390/plants12081619

Interpretive Summary: Copaiba oil-resin has become increasingly popular throughout the world in recent years. Traditionally, the oil has been used topically to treat skin disorders and inflammation. In addition, the oil is also a popular fragrance ingredient. Despite having gained popularity, no standardization guidelines by regulators or the industry have been published. As a result, the quality assessment of the oil is challenging. Additionally, with the increased demand, product adulteration has also emerged as a major problem. In order to help address these issues, a GC/MS method was developed, along with chemometric techniques to assess both known and commercially obtained samples. By combining GC/MS data with chemometrics, “outliers” were easily detected. In addition, an SFC/MS method was applied to unambiguously identify the sample adulteration. By combining these analytical techniques, the overall quality and composition of copaiba oil can be assessed. To the authors’ knowledge, this is the first manuscript describing the use of both GC/MS and SFC/MS to assess the quality of Copaiba oil and to detect and identify adulteration.

Technical Abstract: In recent years, the popularity of copaiba oil-resin has increased worldwide due to its medicinal value and wide applications in industry. Despite its popularity, the oil has not been standardized by industry or regulatory agencies. Product adulteration in order to maximize profits has become a problem. To address these issues the current study describes the chemical and chemometric characterization of forty copaiba oil-resin samples by GC/MS. The results demonstrated, with the exception of commercial samples, all sample groups contained six characteristic compounds (ß-caryophyllene, a-copaene, a-bergamotene, a-humulene, '-muurolene, and ß-bisabolene) in varying concentrations. Furthermore, compositional patterns were observed in individual groups which corresponded to sample origin. Within the commercial group two samples did not contain or only contained one characteristic compound. Principal component analysis (PCA) revealed distinct groups which largely corresponded to sample origin. Moreover, commercial samples were detected by the PCA as “outliers” and formed a group far removed from the other samples. The commercial samples detected as outliers were further subjected to analysis using an SFC/MS method. Product adulteration with soybean oil was clearly detected, with each individual triglyceride in soybean oil being unambiguously identified. By combining these analytical techniques, the overall quality of copaiba oil can be assessed.