A compound in Rosemary called carnosic acid is very similar to THCA in Cannabis. They have rather similar structures and are both diterpenes and antioxidants. THCA degrades to THC and then to cannabinol, carnosic acid degrades to carnosol. Both have medicinal properties such as anti-cancer. So I thought it interesting when I found that carnosic acid content of Rosemary is increased by UV-B. This seems to support the possibility that THCA production is enhanced by UV-B.
"Apart from the influence of the genetic background, contents in carnosic acid (
1) may also be modulated by growth conditions (
Tounekti and Munné-Bosch, 2012). Recently,
Tounekti and Munné-Bosch (2012) have reviewed certain aspects of phenolic diterpene biology, with a particular focus on the physiological, rather than trans-genetic, approaches, to enhancing and improving the phenolic diterpene levels and composition in
Salvia and
Rosmarinus plants and plant extracts. For instance, authors reported that the English climate favours the production of carnosic acid more than the warmer, more arid environmental conditions found in Mediterranean countries where rosemary and sage are typically found. Furthermore, rosemary plants subjected to enhanced levels of UV-B radiation display higher yields of carnosic acid than non-treated plants. Moreover, water, salinity, intense light, and heat stress seem to negatively affect carnosic acid concentrations. Although stress conditions alone seem to decrease levels in carnosic acid (
1), when applied together with supplements, they result in high yields in phenolic diterpenes. This was confirmed when low amounts of fertilizer or kinetin were supplemented to plants upon saline stress (
Tounekti and Munné-Bosch, 2012)."
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