What Climate Produces the Strongest Weed with the Highest THC and CBD Content?

The cannabis plant contains about 450 chemical components, including terpenes, phenols, fatty acids, amino acids, hydrocarbons, carbohydrates, etc. The two main classes of these are terpenoids and cannabinoids. Numerous cannabis plant strains contain more than 104 cannabinoids. However, the most notable examples are plants used as drugs, specifically 9-THC and 9-tetrahydrocannabinolic acid (9-THCA). Conversely, fiber-type plants are known to contain cannabinoid acids primarily, like cannabigerolic acid (CBGA) and cannabidiol acid (CBDA) and their decarboxylated forms, like canna (CBG) and cannabidiol (CBD).

The popular cannabinoids CBD and THC are the decarboxylation end products of CBDA and THCA, respectively. These cannabinoids have become quite popular thanks to their psychoactive effects and medicinal benefits. To better understand these cannabinoids, Turkish researchers looked into the cannabinoid content of various cannabis strains grown in different climatic zones under various supercritical extraction conditions.

To identify the variations, they examined plants from four distinct geographical areas in Turkey and conducted extractions at two distinct pressures and temperatures. According to the Turkish researchers, the new study results are the first to demonstrate how diverse climatic conditions affect the yield of CBD and THC in distinct cannabis strains.

About the Study

Before planting, the researchers collected four different cannabis seeds. Three of them are fairly popular, but the last one is the first national and domestic seed strain known as "Narl." Two seeds are from Konya: Papatya and Elnur. The others; are Gökçeaaç from Ankara and Narl from Samsun. As of the end of 2019, Narl was formally registered.

The seedlings were cultivated in four different climate regions in Konya, Turkey. The seeds were planted in the Konya regions of Umra (June 18, 2019), Altnekin (June 13, 2019), Beyşehir (June 14, 2019), and Meram (June 18, 2019) on the designated days.

The central area is Meram. As a result of the higher prevalence of urbanization, this region experiences the highest average yearly temperature. Due to urbanization, humidity is also lower compared to other places. Beyşehir has high humidity and low temperatures since it features one of Turkey's biggest lakes. The district experiences the most annual precipitation because of the lake.

The areas with the most significant agricultural lands are far away from the city in the regions of Altnekin and Umra, which have moderate temperatures but considerable humidity. In general, each region experiences a different impact of humidity and temperature on local conditions.

Harvesting took place 93 days after planting plants in the Altnekin region, 96 days after growing in both the Beyşehir region and the Meram region, and 104 days after planting in the Umra region. According to the locale, the harvested plants were maintained in a greenhouse without direct sunlight. The plants' upper and bottom sections were switched at intervals while drying to avoid burning the plant, and they were constantly aired to inhibit mold growth.

The researchers hand-picked the cannabis plants to ensure the careful separation of leaves from their stems. Until the samples reached the grinding conditions, the leaves' water content was determined using the Karl Fischer method. Using the Supercritical Fluid Extraction (SFE) method, the flow rate of CO2 was maintained at 100 g/min. At the same time, various extraction parameters (temperature, pressure, and co-solvent impact) were examined for their effects on extraction yield and composition.

Result of the Study

The Papatya species grown in the Altnekin region had the highest THC content (90.82%) among the several cannabis strains grown in the various areas and extracted under SFE-verified conditions. This strain produces 3.71% CBD. The Papatya species grown in Altnekin has the second-highest THC output in the dry cannabis plant (5.41%), trailing only the Papatya strain cultivated in Beyşehir (6.14%).

Compared to other strains, the Elnur strain grown in Beyşehir has the second-highest THC ratio (58.22%). This strain has a CBD concentration of 3.29%. This species' dry cannabis plant extract yield is 4.14%. The Elnur strain, also grown in the Altnekin region, has a THC content of 53.76 percent, and its CBD content is 2.59%. The Papatya species grown in the Beyşehir region (CBD 2.25% and THC 52.16%) was the fourth-ranked strain as regards yield from the strains extracted using SFE after HPLC analysis. With a yield of 6.14%, the Papatya species of the dry cannabis plant, grown in the Beyşehir area, has the most significant output.

When ranked according to yield, the top four strains are two papatya strains and two elnur strains. Beyşehir and Altnekin are the top two cultivating regions, coming in the first four regions. When the locations are compared in terms of their meteorological conditions, the researchers noted that Beyşehir had the most rainfall (1690 mm) during the planting season of 2019 and that the Altnekin region came in second (1070 mm). These two places are also the most humid region when measured by the humidity metric (59.11% and 59.93%, respectively). They are among the less dry locations regarding temperature (13.49 °C and 13.42 °C).

Cannabis can adapt to a wide range of climate conditions. It is a plant that has spread from a warm temperature zone to a subtropical climate zone. While the cannabis plant requires a high need for pre-planting rains, It can grow quickly in humid and arid climates if watered. High humidity and drought also both hasten the growth of cannabis plants. From this vantage point, the two regions (Altnekin and Beyşehir) with the highest yield among those cultivated meet this criterion the best. In terms of the association between climate and the results, the research is consistent.

Conclusion

This study involved the SFE of four cannabis plant strains cultivated in four distinct climate zones. The highest yields of CBD and THC were obtained at 2 hours of conditions of 33 MPa,40 °C, and 2.0 wt% ethanol co-solvent. The characteristic that seemed to affect the extraction yield the most was pressure.

Additionally, it was discovered that the cannabis grown in areas with higher relative humidity, lower temperatures, and more rain had higher yields. Although this work emphasizes the subject to some extent, more research with cannabis strains grown in diverse geographic locations under varied pressure and temperature values is needed to understand and perfect the extraction yield for SFE fully.