## 3 Results and Discussion
It is worth noting that 7 MER was also present in the rosmary extract that had been in contact with methanol for 7 days, but in much smaller quantities than those encountered after the 2 months of maceration [4]. According to [PERSON] et al. (2013) [25], the proposed degradation pathway of carnosic acid in methanol solution is presented in Figure S1. The same authors considered that the compounds rosmanol (RO) and 7-O-methyl-rosmanol (7 MER), due to their stability, are the final products of the degradation of CA in methanol. Rosmanol (RO) is formed from carnosic acid and carnosol in polar solvents such as methanol and water. However, it was not detected in the examined plant extracts containing carnosic acid or carnosol, possibly for the same reasons that 7 MER was not detected. CA was identified in lemon balm (_Melissa officinalis_) by [PERSON] et al., 2003 [26]. Of the three species of Mentha studied, _M. pulgeium_, _M. spicata_ and _M. longifolia_, carnosic acid was identified only in _M. spicata_ and _M. longifolia_, with very little quantitative difference between them. CA and CS were identified in _Ocimum basilicum_. In the work by [PERSON] et al. (2003) [27], CA was detected but not CS. The difference in CS's effect between the two procedures may be due to the different extraction times (5 min in the work by [PERSON] et al., 2003 [27]). In _S. rosmarius_ and in the variety _prostratus_ Pasq., CA, CS and 12-MCA were identified. As expected from the literature, in _S. officinalis_ and _S. fruticosa_, CA, CS and 12-MCA were identified. Of particular interest is the species _S. pomifera_. Indeed, both in _S. pomifera_ subsp. _pomifera_ of Cretan origin and in _S. pomifera_ subsp. _calcyina_ of Mainland Greece, the same  
Figure 4: \({}^{1}\)H-NMR spectrum of _S. rosmarius_ Spenn. in CDCl\({}_{3}\). abietane diterpenes were identified. However, the quantitative differences between the individual substances were significant. As shown in Table 3, _S. pomifera_ L. subsp. _pomifera_ had one of the highest concentrations of carnosic acid, while _S. pomifera_ subsp. _alycina_ (Sm) [PERSON] one of the lowest. [PERSON] et al. (2019) [28] analyzed the methanolic extracts of _S. pomifera_ L. and _S. fruticosa_ Mill. by the HPLC-ESI-QTOF-MS method. Regarding abietane diterpenes, the results showed that _S. pomifera_ L. contained only 12-\(O\)-methylcarnosate and isomers of RO, without CA and CS, which is in direct contrast to the results of our study. _S. pomifera_ L. in the study by [PERSON] et al. (2019) [28] was collected in Crete shortly before its flowering, while the methanolic extract was made with a Soxhlet device for 6 h in the following solvent ratio: drug = 20:1. _S. pomifera_ L. in our study was also collected from Crete (Mount Psiloritis), but during its flowering. The drug-solvent ratios were almost the same in both studies (1:20 versus 1:30). It is estimated that the differences in the collection time and the preparation of the methanolic extracts, or the different methods of analysis, do not justify such a qualitative difference between the results of these two works. Moreover, [PERSON] et al. (2019), in the extract of _S. fruticosa_ Mill. under the same extraction conditions as _S. pomifera_ L., identified CA, CS and 12 MCA just as we did. Note that although [PERSON] et al. (2019) [28] do not refer to a subspecies of _S. pomifera_ that was studied, i.e., _pomifera_ or _alycina_, we considered that it is _S. pomifera_ subsp. _pomifera_ since it was collected in Crete where only this subspecies thrives. Of the 61 plants of the Labiate family studied, _S. somalensis_ Vatke was the richest in both CA (32.15 \(\pm\) 0.93 mg/g dried drug) and CS (4.24 \(\pm\) 0.04 mg/g of dried drug), making this species an excellent source of these two substances. It is worth noting that for the first time, quantitative data of the extract of the plant _S. somalensis_ Vatke concerning CA and CS are reported. To confirm the results, we also analyzed the extract of _S.