Identification of Terpene Compositions in the Leaves and Inflorescences of Hybrid Cannabis Species Using Headspace-Gas Chromatography/Mass Spectrometry.

Although cannabidiol and tetrahydrocannabinol in Cannabis species exert their pharmacological effects via the endocannabinoid system, it is believed that other phytochemicals, particularly terpenes, can modulate therapeutic outcomes through the entourage effect. Therefore, to gain a better understanding of the pharmacological effects of Cannabis, obtaining information on phytochemical compositions, including mono-, di-, and sesqui-terpenes in Cannabis species is essential. Applying a sophisticated analytical method is indispensable. In this study, headspace-gas chromatography/mass spectrometry (HS-GC/MS) was employed to identify major terpenes in the leaves and inflorescences of hybrid Cannabis species. The incubation time and temperature conditions for HS-GC/MS were optimized. This method was successfully applied to the leaves (n = 9) and inflorescences (n = 7) of hybrid Cannabis species. A total of 26 terpenes in Cannabis species were detected, and six major components, such as α-pinene (9.8-2270 µg/g), ß-pinene (2.6-930 µg/g), myrcene (0.7-17,400 µg/g), limonene (1.3-300 µg/g), ß-caryophyllene (60-3300 µg/g), and α-humulene (40-870 µg/g), were quantified. Each sample showed different terpene compositions, but six major terpenes among all the terpenes detected were consistently found in both the leaves and inflorescences of hybrid Cannabis species. In this study, the six major terpenes' potential in hybrid Cannabis species was evaluated as biomarkers to distinguish hybrid Cannabis species samples. This study contributes to a better understanding of the entourage effect of Cannabis-based botanical drugs.

Chemical transformation of cannabidiol into psychotropic cannabinoids under acidic reaction conditions: Identification of transformed products by GC-MS.

Recently, cannabidiol (CBD), one of the major components of the Cannabis species, has been a focus in the cannabis industry due to its various pharmacological effects. Interestingly, CBD can be converted into several psychoactive cannabinoids, such as 9-tetrahydrocannabinol (Δ9-THC) and its structural isomers, under acidic reaction conditions. In this study, chemical transformation of CBD in ethanol solution was conducted with variation in pH at 2.0, 3.5, and 5.0 by addition of 0.1 M hydrochloric acid (HCl). These resulting solutions were derivatized with trimethylsilyl (TMS) reagent and analyzed using GC/MS-scan mode. Time profiles of CBD degradation and transformation of products were examined according to variations in pH and temperature. Several transformed products produced after the acidic reaction of CBD were identified by matching retention times and mass spectra to authentic standards. Regarding the identification of products without authentic standards, the EI-mass spectra of such cannabinoid-OTMS derivatives were interpreted according to structural class, suggesting mass fragmentation pathways. From the GC/MS data, Δ9-THC, CBC, and ethoxy-hexahydrocannabinol (HHC) analogs were shown to be major components, and THC isomers (Δ8- and Δ10-THCs) and 9-hydroxy-HHC were observed as minor components. Using time profile data, the acidity of the reaction solution was an important factor in degradation of CBD. Degradation of CBD and formation of THC rarely occurred at pH 5.0, even at 70 °C with a long process time of 24 h. In contrast, degradation of CBD occurred readily at pH 3.5 and 30 °C over a short process time and was further accelerated by lowering pH, increasing temperature, and lengthening the process time. Based on profile data and identified transformed products, formation pathways from the degradation of CBD under acidic reaction conditions are suggested. Among the transformed products, seven components are known to have psychoactive effects. Thus, industrial CBD manufacturing processes in food and cosmetic products should be carefully controlled. These results will provide important guidelines on the control of manufacturing processes, storage, fermentation processes, and new regulation in industrial applications of CBD.