## 3 Results and Discussion
dictamus._) were found to contain any of the analyzed substances. In the study by [PERSON] et al. (2011, 2012) [20; 21], both CA and CS were identified in _O. majorana_ and in _O. vulgare_ of Turkish origin using LC-ESI-MS/MS, but no quantitative data were reported. [PERSON] et al. (2009) [22] also identified CA and CS in _O. vulgare_ of Mexican origin. Figure 2: \({}^{1}\)H-NMR spectra in CDCl\({}_{3}\) in the 6.45–6.95 ppm region, showing the characteristic peaks of the studied compounds—carmosic acid (CA), carnosol (CS), 12-O-methyl-carnostic acid (12 MCA), 7-O-methyl-_epi_-rosmanol (MER), and rosamol (RO)—that were used for integration. [PERSON] et al. (2005) [23] identified CS but not CA in \(O\). _majorana_, attributing this effect to plant material processing, CA's sensitivity to polar solvents and the elevated temperature (90-100 \({}^{\circ}\)C infusion with distilled water for 30 min in a water bath, extract in Soxhlet using n-hexane and ethanol for 6 h). In our study, the large area of the putative CA peak in the extract of \(O\). _vulgare_ subsp. _hirthum_ led us to obtain the \({}^{1}\)H-NMR spectra of the extract in CD\({}_{3}\)OD, where it was found that the peaks under investigation were not related to those of CA or CS (Figure 3). The same approach was also followed for \(O\). _majorana_ and \(O\). _dictamus_. Another method to address identification issues, aside from using a different deuterated solvent to obtain a spectrum, involved adding a known amount of the pure isolate to the test extract and recording a new \({}^{1}\)H-NMR spectrum. If the compound was originally present in the extract, its peak in the new spectrum would appear larger compared to the original spectrum. Conversely, if the compound was absent, no increase in the existing peaks would be observed; instead, new peaks corresponding to the added pure substance would emerge. No carnosic acid, carnosol or any of the other studied substances were identified in the thyme, _Thymbra capitata_ (L.[PERSON]. [PERSON] et al. (2011) [20] have identified in thyme of Turkish origin both CS and CA. The researchers extracted the plant with a mixture of methanol/water = 80/20. In this study, thyme is referred to as \"Anglo-Saxon Thyme\" without mentioning the plant's Latin binomial name. It is most likely referring to _Thymus vulgaris_. However, it is important to note that _Thymus vulgaris_, not _Thymbra capitata_ (L.) [PERSON], is more commonly found in Turkey, and there is no reference to the presence of CA or any other abietane-type dipterpene in this context. **Plants that contained at least one of the metabolites tested**  
Moreover, the screening of the 61 studied plants of Lamiaceae showed that in 20 species, at least one abietane derivative has been detected (_Salvia_ (16), _Melissa_, _Oci  
Figure 3: Comparison between the \({}^{1}\)H-NMR (CDCl\({}_{3}\) and CD\({}_{3}\)OD) spectra of methanolic extracts of \(S\). _rosmarinus_ and \(O\). _dictamus_ L. subsp. _hirthum_ in the range from 6.40 to 7.40 ppm with the internal standard (i.s. ), (s) of H-14 (CS) (\({}^{1}\)H integration) and (s) of H-14 (CA) (\({}^{1}\)H integration). mum, Mentha (2)). 7 MER and RO were not identified in any extracts, while CA, CS and 12 MCA were all detected simultaneously in species of the genera _Salvu_ (12) and _Rosmarirus_ (2). The quantitative results for the 61 Labiatae family plants containing at least one of the tested compounds are summarized in Table 3.  
_S. rosmarirus_ is a notable example of a plant that contains significant amounts of CA, CS and 12 MCA, as depicted in Figure 4.  
The highest concentration of carnosic acid was found in the leaf extract of _S. somalensis_, with a value of 32.15 \(\pm\) 0.93 mg/g of dried material, making this plant an excellent source for isolating carnosic acid. The presence of CA in _S. somalensis_ has also been reported by [PERSON] et al., 2012 [24], but without reporting quantitative data.