## 2 Results and Discussion
### Quantitative Analysis of 34 Cannabis sativa L. Samples
THC, CBD, and CBDA were the major cannabinoids with concentration levels in the ranges of 0.05 (\(\pm\)0.01)-0.54 (\(\pm\)0.05)% \(w/w\), 0.32 (\(\pm\)0.08)-4.8 (\(\pm\)0.2)% \(w/w\), and 1.74 (\(\pm\)0.02)-21.7 (\(\pm\)0.4)% \(w/w\), respectively. THCA represented the minor component, with a content always lower than 0.16 \(\pm\) 0.02% \(w/w\), while CBN was always lower than LOQ in the samples under study. In regard to major cannabinoids, THC:CBD ratio affects the metabolism and therapeutic effects of cannabis, due to the different interaction with cannabinoid receptors CBD 1 and 2 [13], thus classifying the corresponding plants in fiber type (or cannabis light) and drug type (or marijuana). For most of the analyzed samples, THC:CBD ratios resulted between 1:3 and 1:11. Only two samples had much higher CBD values than THC, as the THC: CBD ratios were 1:13 and 1:26 for Moon Rock-Love Canapa (Sample 33 in Table 3) and Malana-Baby J (Sample 22 in Table 3), respectively. However, all samples showed THC:CBD ratio less than 1, thus ascertaining the fiber type of the plants. Currently, no countries consider THC:CBD ratios in their own regulations for legalized medical or recreational cannabis [21]. Furthermore, decarboxylation of THCA and CBDA acid precursors yields a greater amount of THC and CBD, respectively, making it necessary to evaluate the total content of these cannabinoids occurring in the infloreserences, in order to confirm the chemotype classification. The total THC content was determined as follows: (THCA \(\times\) 0.877) + THC. Similarly, the total CBD content was determined as (CBDA \(\times\) 0.877) + CBD, considering 0.877 as the ratio of the molecular mass of decarboxylated form and the carboxylated form. Indeed, the neutral compound is lighter, as it has about 87.7% of the mass of the acid precursor. When THCA is converted into THC, or CBDA into CBD, the total weight of the newly formed cannabinoid is lower than the total dry weight of the herb. As shown in Table 3, a low total content of THC was found in all the samples, as it ranged from 0.09 to 0.59% \(w/w\). The total CBD content ranged from 2.62 to 20.27% \(w/w\) and it was not related to THC level. The data obtained corroborated that the evaluated samples were properly classified as hemp, as the amount of THC was below the legal limits. In fact, according to the current legislation concerning the cultivation of _Cannabis sativa_ L. the total THC content must not exceed 0.2%, and in any case, 0.6%. Finally, the CBN/THC ratio determination allowed for evaluation of the preservation status of the inflorescence samples. In \"old\" cannabis samples, i.e., more than 6 months, or in samples exposed to light or high temperatures, the oxidation of THC leads to the formation of CBN [25] with CBN/THC ratios higher than 0.013. In all 34 samples under study, CBN contents were lower than the LOQ, thus indicating well-stored or fresh infloreserences. As the cannabis products analysed are also sold on websites, our results can likely represent a view of cannabis light products in the Italian and international markets.