Composition of the essential oils and extracts of two populations of Cannabis sativa L. ssp. spontanea from Austria

Journal of Essential Oil Research: JEOR, May/Jun 2003 by Novak, Johannes, Franz, Chlodwig

Abstract

The essential oil and the solvent extract of two populations of Cannabis sativa L. ssp. spontanea growing wild in Austria were analyzed comparatively. In the essential oil, myrcene (31% and 27%, respectively), (E)-beta-ocilnene (13% and 3%, respectively) and beta-caryophyllene (11 % and 16%, respectively) were found, while in the solvent extract the non-hallucinogeneous cannabidiol (77% and 59%, respectively) dominated. The hallucinogeneous delta-9-tetrahydrocannabinol (THC) was also found in the solvent extract at a level of less than 1%.

Key Word Index

Cannabissativa ssp. spontanea, Cannabaceae, essential oil composition, myrcene, (E)-beta-ocii-nene, beta-caryophyllene, cannabinoids

The Plant

In Cannabis sativa L. ssp. spontanea (formerly Cannabis ruderalis) (Cannabaceae) the perianth of the female flowers is in contrast to C. sativa ssp. sativa still present; the fruit is brownish and has a peduncle-like ringbulge. It is a ruderal, but a rare plant in the east of Austria (1).

Source

Two populations of C. sativa L. ssp. spontanea ("Albrechtsfeld" and "Schoschtolacke") from the region of lake Neusiedl, Burgenland, eastern Austria were sampled in June, 1998, at the beginning of seed ripening. At each population upper parts of approximately 10 plants were sampled. Voucher specimens were deposited in the Herbarium of the Institute for Applied Botany, University of Veterinary Medicine, Vienna.

Plant Part

For distillation and extraction, only fresh material was used, since drying results in a high loss (30-40%) of the essential oil (2). Twenty g of fresh plant material (upper plant parts) were distilled in a modified Clevenger apparatus for 3 h. The solvent extracts were prepared by adding CH^sub 2^Cl^sub 2^ to 1 g fresh material of hemp (upper plant parts); extraction was performed in an ultrasonic bath for 15 min.

The essential oil (5 (mu)L) was diluted with CH^sub 2^Cl^sub 2^ (495 (mu)L) prior to analyses. GC/MS-analyses were performed on a HP 6890 coupled with a HP 5972 MSD and fitted with a HP 30 m x 0.25 mm capillary column coated with HP-5MS (0.25 (mu)m film thickness). The analytical conditions were: carrier gas helium, injector temperature 250 deg C, split ratio 50:1, temperature programme 50 deg -140 deg C at 5 deg C/min and 140-170 deg C at 2 deg C/min. Components were identified by comparing their retention indices (RI) and mass spectra (3-5).

Previous Work

The essential oil of C. sativa has been the subject of previous studies (2, 6-15 and references cited therein).

Present Work

Mono- and sesquiterpenes: The oil of C. sativa L. ssp. spontanea contains as main compounds alpha-pinene (9% and 6%, respectively), myrcene (32% and 28%, respectively), beta-- caryophyllene (11% and 16%, respectively) and beta-caryophyllene oxide (7% and 8%, respectively) (Table I). However, the main differences between the two populations could be found in the high content of (E)-beta-ocimene with a very high content of 12.6% from "Albrechtsfeld" and a low content of 3% from "Schoschtolacke." Compared to "Schoschtolacke," the content of alpha-humulene was approximately the half at "Albrechtsfeld" (3.2%).

The oil compositions reported here differ very much from Ross et al. (2), Hendriks et al. (8) and Nigam et al. (13), where (E)-beta-ocimene was only found in traces or not at all. Hendriks et al. (8) and Nigam et al. (13) found alpha-pinene, beta-- pinene and myrcene at alevel of less than 1%, beta-caryophyllene instead reached 37% and 45%, respectively. In contrast, Ross et al. (2) noticed beta-caryophyllene to be present at only 1.3%. Myrcene (67%) and limonene (16%) were much higher than reported elsewhere (2). The Austrian populations of this report are within the range of (12) where different cultivars (especially European fiber cultivars) were analyzed.

Composition of cannabinoids: Regarding the cannabinoids in the oil, relatively high percentages of the non-- hallucinogeneous cannabidiol (CBD) (9.8% "Albrechtsfeld" and 10.9% "Schoschtolacke," respectively) could be found. The hallucinogenic delta-9-tetrahydrocannabinol (THC) was only present at "Schoschtolacke," and here only at low amounts (0.7%). CBD in the oil was still very high, but it's content was strictly dependant on the distillation conditions. The presence of cannabinoids in oils at higher amounts (11,17 and this report) as well as the almost absence of cannabinoids (12 and 16) are also dependant on distillation conditions and the state of the plant material being distilled. In the solvent extract, the content of CBD was extremely high (76.6% and 58.8%, respectively), while THC was always (even in the extract) below 1%. These can be regarded as being populations with a low content of THC, while the amount of CBD (especially in the extracts) was very high. So the ratio of CBD/THC, which is used for characterizing and distinguishing "fiber" from "drug" genotypes (18), is very much in favor of the fiber types.

Alkanes: Hendriks et al. (19) found nonacosane as main compound in the alkane-fraction obtained by extraction (55%) and at 11% in the oil. Nonacosane was also detected in the extracts of our study at 9% ("Albrechtsfeld") and 18% ("Schoschtolacke"), while it was absent in the oil (Table I).