Ocimum campechianum Mill. (Peruvian basil) is an essential oil-bearing plant of the Lamiaceae family. Volatile oil produced through steam distillation of Peruvian basil was examined to establish the aromatic and stable isotope profiles of samples (n = 9) from three different cultivated plots in Peru. The resulting essential oils were analyzed by GC/FID, GC/MS, and GC/IRMS. In accordance with findings from other researchers, multiple chemotypes, defined by the most abundant aromatic compounds, exist within these populations. Overall, 55% of samples are the eugenol chemotype (values ranging 15.4–30.2%), 33% are the methyl eugenol chemotype (values ranging 68.1–68.7%), and a single sample is a mixture of both chemotypes, containing high levels of both eugenol (38.1%) and methyl eugenol (8.6%). Stable isotope ratios, δ²H and δ¹³C, performed on prominent compounds provide supporting data for distinguishing chemotypes. Complete aromatic profiles, stable isotope ratios, and essential oil yield are established for each sample. This study confirms the existence of multiple chemotypes and, for the first time, to the author’s best knowledge, establishes stable isotope ratios for O. campechianum essential oil, which proves a useful tool in further investigating plant metabolism and determining essential oil authenticity.

Ylang-ylang (Cananga odorata Hook.f. & Thoms.) is cultivated in many tropical areas of the world for the multiple applications of the essential oil extracted from its flowers. The aim of this work was to determine the concentrations of macro-nutrientes and micro-nutrients in the different ylang-ylang organs in two treatments, without fertilization and with commercial fertilization, based on a nutritional analysis of the soil of a production farm located in Chongón, Guayas, Ecuador. The concentrations of N, P and Mg were significantly higher in the treatment with fertilization (16.82; 2.96; 3.81 vs. 14.63; 2.39; 3.12 g/kg, respectively). Concerning micronutrients, in the treatment with fertilization, Mn, Cu and Mo concentrations were significantly higher (73.00; 13.50; 1.28 vs. 44.96; 9.08; 0.50 mg/kg), while Cl concentration was significantly lower (1692.58 vs. 3488.25 mg/kg). Significant differences were also found in nutrient concentration as a function of organs. The C. odorata N, P, K, Ca, Mg and S extraction is 30.83; 3.46; 12.87; 25.50; 4.85 and 3.35 kg/ha, respectively. Higher concentrations of N, Ca and K are suggested for this crop. These results contribute to the improvement of the quality of fertilization in the ylang-ylang cultivation.