Effect of Different Soil Treatments on Production and Chemical Composition of Essential Oils Extracted from <i>Foeniculum vulgare</i> Mill., <i>Origanum vulgare</i> L. and <i>Thymus vulgaris</i> L.
Antonio Raffo,
Filippo Umberto Sapienza,
Roberta Astolfi,
Gabriele Lombardi,
Caterina Fraschetti,
Mijat Božović,
Marco Artini,
Rosanna Papa,
Marika Trecca,
Simona Fiorentino,
Valerio Vecchiarelli,
Claudia Papalini,
Laura Selan,
Rino Ragno
Affiliations
Antonio Raffo
CREA-Research Centre for Food and Nutrition, Via Ardeatina, 546, 00178 Rome, Italy
Filippo Umberto Sapienza
Rome Center for Molecular Design, Department of Drug Chemistry and Technology, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
Roberta Astolfi
Rome Center for Molecular Design, Department of Drug Chemistry and Technology, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
Gabriele Lombardi
Department of Environmental Biology, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
Caterina Fraschetti
Department of Drug Chemistry and Technology, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
Mijat Božović
Faculty of Natural Science and Mathematics, University of Montenegro, Džordža Vašingtona bb, 81000 Podgorica, Montenegro
Marco Artini
Department of Public Health and Infectious Diseases, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
Rosanna Papa
Department of Public Health and Infectious Diseases, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
Marika Trecca
Department of Public Health and Infectious Diseases, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
Simona Fiorentino
Centro Appenninico del Terminillo “Carlo Jucci”, Perugia University, Via Comunali 43, 02100 Rieti, Italy
Valerio Vecchiarelli
Centro Appenninico del Terminillo “Carlo Jucci”, Perugia University, Via Comunali 43, 02100 Rieti, Italy
Claudia Papalini
ARSIAL Agenzia Regionale per lo Sviluppo e l’Innovazione dell’Agricoltura del Lazio, Via R. Lanciani 38, 00162 Rome, Italy
Laura Selan
Department of Public Health and Infectious Diseases, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
Rino Ragno
Rome Center for Molecular Design, Department of Drug Chemistry and Technology, Sapienza University, p.le Aldo Moro 5, 00185 Rome, Italy
The aim of the study was to investigate how essential oil production and associated chemical composition and related biological activity could be influenced by different cultivation treatments and distillation methods. Foeniculum vulgare Mill. (fennel), Origanum vulgare L. (oregano) and Thymus vulgaris L. (thyme) were cultivated in absence of any fertilizer (control) and in presence of three different fertilizers: a chemical one with augmented mineral phosphorus and potassium, a second added with hydrolyzed organic substance and mineral phosphorus and potassium (organic–mineral) and a third one treated with a high content of organic nitrogen of protein origin (organic). The plants were subjected to steam distillation using two modalities, recycled and continuous, to obtain 32 essential oil samples. Chemical composition analysis was performed using gas chromatography–mass spectrometry; in vitro antimicrobial activity was evaluated using a broth microdilution method. In general, the recycled distillation method appeared to have a slightly higher yield than the continuous method. The “mineral” and “organic–mineral” treatments resulted in a higher yield compared to the “organic” or “control” treatments, and this was particularly evident in the recycled method. The “control” plants had a lower yield of essential oils. Anethole (13.9–59.5%) and estragole (13.4–52.2%) were the main constituents of the fennel oils; p-cymene and its derivatives carvacrol and thymol were the main constituents of the oregano and thyme samples. The antimicrobial activity of the thyme oils on Staphylococcus aureus ranged from 0.31 to 0.16% (v/v); a lower effect of the oregano samples and no activity of the fennel samples were observed. The essential oils failed to inhibit the growth of Pseudomonas aeruginosa strains.
