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Bulgaria is famous for its oil-bearing rose. R. damascena Mill. and R. alba L. are mainly cultivated in the country, but a recent survey of industrial plantations in 2020 revealed that R. centifolia L. and hybrids of R. damascena Mill. X R. gallica L. are also common in the rose valley. Although their essential oil cannot be compared in quality with the classic, these species are preferred by farmers with high yields of flowers and resistance to diseases and pests. All these roses are also used to produce rose water and extracts. The aim of this investigation was to compare the yield and chromatographic fingerprints of seven rose oils and hydrosols produced in Bulgaria. The quantitative composition of the main components of the oils was compared with the norms of the world standards. Our study showed that the yield of essential oil from these roses was in the range of 0.015–0.048%. The main group in the chemical composition is terpene alcohols, which vary in range: geraniol (15.85–34.02%), citronellol (6.70–28.72%), and nerol (5.80–11.90%) but with a different ratio. Hydrocarbons are represented by saturated aliphatic homologs with an odd number of carbon atoms, the main ones being nonadecane (8.10–22.67%), heneicosane (4.37–10.21%), heptadecane (1.07–2.98%), and triclosan (0.81–5.90%). In contrast, the chemical profile of the hydrosols was performed using phenylethyl alcohol (27.45–69.88%), geraniol (13.72–28.67%), and citronelol+nerol (4.56–17.37%). The results show that the presence of plantations with a genotype different from that of R. damascena implies differences in the quality of rose oils and hydrosols. This determines their properties of use.

Many plants belonging to the Lamiaceae family are rich in essential oils (EOs) which are intensively used for aromatherapy, food and beverage flavoring, alternative medicine, cosmetics, and perfumery. Aerial parts of Thymus vulgaris L., Thymus pannonicus All., Lavandula angustifolia L., Lavandula x intermedia, Origanum vulgare L., and Origanum vulgare var. aureum L. were subjected to hydrodistillation, and both resulting fractions were analyzed. The purpose of this study was to determine the chemical composition, antioxidant activity, and total phenolic content of six essential oils and their corresponding hydrolats (HDs) through GC-MS and spectrophotometric analyses. Overall, 161 compounds were identified, some found exclusively in essential oils and others in hydrolats, making them individual products with specific end purposes. The total phenolic content was the highest for the Thymus vulgaris L. EOs (3022 ± mg GAE L−1), because of its high phenolic oxygenated monoterpenes content (thymol and carvacrol) and the smallest for the Lavandula angustifolia L. EOs (258.31 ± 44.29 mg GAE L−1), while hydrolats varied from 183.85 ± 0.22 mg GAE L−1 for Thymus vulgaris L. HD and 7.73 mg GAE L−1 for Thymus pannonicus All. HD. Significant antioxidant effects determined through DPPH• and ABTS•+ assays were also observed in samples with higher hydrophilic compounds. The highest antioxidant activity was determined for Thymus vulgaris L. EO and its corresponding HD. Although EOs are the principal traded economic product, HDs represent a valuable by-product that could still present intense antiseptic activities, similar to their corresponding EOs (thyme and oregano), or have multiple aromatherapy, cosmetics, and household applications (lavender and lavandin).

The use of vegetable compounds as an alternative for control phytopathogens has received prominence in research to enable sustainable management methods in agriculture. Fungi such as Didymella bryoniae, Pyricularia grisea, Rhizoctonia solani, and Sclerotium rolfsii are important for causing great losses in production. In this context, the purpose was to evaluate the fungitoxicity of plant oils in inhibiting themycelial growth of pathogenic fungi. The tests were conducted in completely randomized design with 13 treatments (Cymbopogon nardus, C. citratus, Lippia alba, Eugenia dysenterica, Caryocar brasiliense, Azadirachta indica, A. indica – commercial – Ageratumconyzoides, Jatropha curcas, Eucalyptus sp., Mentha piperita, Tiofanato metílico e Testemunha) and four replications. To evaluate the fungitoxicity were distributed, 1.5 μ L mL-1 of the treatment were distributed on the surface of PDA culture medium. The Eucalyptus sp., M. piperita, L. alba, C. nardus, and C. citratus essential oils inhibited the growth of the fungus P. grisea. D. bryoniae did not growth only in the treatment of C. citratus. The R. solani and S. rolfsii fungi did not show mycelial growth when subjected to treatments of M. piperita, L. alba, C. nardus, and C. citrates essential oils., O uso de compostos vegetais como alternativa para controle de fitopatógenos tem recebido destaque em pesquisas que visam viabilizar métodos de manejo sustentável na agricultura. Fungos como Didymella bryoniae, Pyricularia grisea, Rhizoctonia solani e Sclerotium rolfsii são importantes por causarem grandes perdas na produção. Neste contexto, objetivou-se avaliar a fungitoxicidade de óleos vegetais na inibição do crescimento de fungos fitopatogênicos. Os ensaios foram conduzidos em delineamento inteiramente casualizado com 13 tratamentos (Cymbopogon nardus, C. citratus, Lippia alba, Eugenia dysenterica, Caryocar brasiliense, Azadirachta indica, A. indica - comercial, Ageratum conyzoides, Jatropha curcas, Eucalyptus sp., Mentha piperita, Tiofanato metílico e Testemunha) e quatro repetições. Para a avaliação da fungitoxicidade, foram distribuídos 1,5μ L mL-1 dos tratamentos na superfície do meio de cultura BDA (batata-dextrose-ágar). Os óleos essenciais de Eucalyptus sp., M. piperita, L. alba, C. nardus e C. citratus inibiram o crescimento de P. grisea. D. bryoniae não apresentou crescimento micelial apenas no óleo de C. citratus. Os fungos R. solani e S. rolfsii não cresceram quando submetidos aos tratamentos de óleos essenciais de M. piperita, L. alba, C. nardus e C. citratus.

Legionella pneumophila je ubikvitarna bakterija koja najbolje preživljava u vodenim staništima poput jezera, rijeka, močvara i vlažnog tla. Nalazimo ju u bazenima, spa centrima, saunama i tuševima. Može uzrokovati legionarsku bolest i pontijačku groznicu ako se putem kontaminiranog aerosola unese u organizam. Osim uobičajenih tehnika prevencije legionele sve se više istražuju prirodne metode poput eteričnih ulja i njihovih produkata, hidrolata. Hidrolati su vodene mase koje zadržavaju slična molekulska svojstva kao i ulje, i za razliku od njih topiva su u vodi. Imaju jača antibakterijska, antivirusna, antigljivična i protuupalna svojstva, ali su nestabilni, lako se kvare ako se ne čuvaju pravilno. Cilj diplomskog rada je bio ispitati antimikrobno i antiagregativno djelovanje hidrolata smilja (Helichrysum italicum), ružmarina (Rosmarinus officinalis) i lavandina (Lavandula hybrida) na legionelu. Rezultati istraživanja pokazuju da je L. pneumophila osjetljiva na sve testirane hidrolate. Najbolju antibakterijsku aktivnost u bujonu pokazali su hidrolati smilja (Helicrysum italicum) i ružmarina (Rosmarinus officinalis), s MIK i MBK vrijednostima od 25%. Najbolju antibakterijsku aktivnost u vodi pokazao je hidrolat ružmarina (Rosmarinus officinalis), s MIK vrijednosti od 6,25%,. Najbolje agregacijsko djelovanje imao je hidrolat smilja (Helicrysum italicum). U sterilnoj vodi iz slavine je postotak agregacije iznosio 64 %, a u bujonu 64,8 %. Najbolje rezultate za kombinaciju hidrolata u bujonu na agregaciju ima kombinacija lavandina i ružmarina sa 73,52%, te možemo reći da ta dva hidrolata imaju sinergistički učinak. Svi testirani hidrolati imaju velik potencijal primjene u kontroli i suzbijanju legioneloze. Legionella pneumophila is a ubiquitous bacterium with affinity for aquatic habitats such as lakes, rivers, wetlands and moist soil. Legionella can be found in swimming pools, spas, saunas and showers. It can cause Legionnaires' disease and Pontiac fever if it get into the body through the contaminated aerosols. Except the usual techniques of prevention of Legionella there are natural methods such as essential oils and their products, like hydrolats. Hydrolats are floral waters that hold similar molecular properties like oil, and unlike them are soluble in water. They have strong antibacterial, antiviral, antifungal and anti-inflammatory properties, but they are unstable, they can easily spoil if they are not stored properly. The aim of the study was to investigate the antimicrobial and antiaggregative activity of immortelle hydrolat (Helichrysum italicum), rosemary hydrolat (Rosmarinus officinalis) and lavender hydrolat (Lavandula hybrida) to legionella. The results showed that L. pneumophila is sensitive to all tested hydrolats. The best antibacterial activity in broth showed immortelle hydrolat (Helicrysum italicum) and rosemary immortelle (Rosmarinus officinalis), with a MIC and MBC of 25%. The best antibacterial activity in water showed rosemary hydrolat (Rosmarinus officinalis), with a MIC of 6.25%. The best effect on the aggregation had immortelle hydrolat (Helicrysum italicum) and the percentage of aggregation in water was 64%, in the broth 64.8%. The best results on the aggregation for the combination hydrolat broth has a combination of lavender and rosemary hydrolat with 73.52%. All tested hydrolats have great potential applications in the control and prevention of legionellosis.

This work is a collection of my teaching activities and postdoctoral researches carried out within the laboratory "Chimie des Produits Naturels" (CPN) and the 'Natural resources' research project supported by the UMR CNRS 6134 "Environmental Sciences" of the University of Corsica Pasquale Paoli. The works concern the characterization of aromatic and medicinal plants (AMP) and products of agriculture through the volatile complex mixtures that are derived. These complex mixtures are essential oils, hydrosols, solvent extracts and volatile fractions. The different steps of the analytical sequence were discussed, the choice of plants and their sampling, the sample preparation, analysis, interpretation of the results using the statistical tool and their enhancement through the research of active molecules. The first part deals with the characterization of the essential oils, hydrosols, solvent extracts and volatile fractions from AMP and the aromas of olive-oils and citrus juices. To do this, we examined the potential of alternative methods to hydrodistillation, such as microwave-assisted extraction and Solid Phase MicroExtraction. The analysis is performed in the laboratory CPN using chromatographic techniques as Gas Chromatography (GC) for quantification and GC coupled with Mass Spectrometry (GC/MS) for the identification of the constituents. We have optimized the analytical sequence using complementary techniques such as column chromatography, SM using chemical ionization mode and the Nuclear Magnetic Resonance for the identification of missing references libraries molecules. The second part concerns the development of a new research axis which aims to highlight the active compounds through the study of antibacterial and antifungal activities of essential oils and plant extracts. We have highlighted the biological properties of essential oils and extracts against bacteria involved in food borne illness and nosocomial infections. The last part is developing the prospects aimed at strengthening the work on the AMP and agricultural products of Corsica by exploring new matrices (polar fraction) and new extraction techniques. The valorization of plant complex mixtures by the search for new antibiotics surpassing the mechanisms of resistance of bacteria and of new antioxidants remains scientific challenge for the future., Ce travail constitue un recueil des mes activités d'enseignement et de recherche postdoctorales réalisées au sein du laboratoire " Chimie des Produits Naturels " (CPN) dans le cadre du projet de recherche " Ressources Naturels " soutenu par l'UMR CNRS 6134 " Sciences de l'Environnement " de l'Université de Corse Pasquale Paoli. Les travaux concernent la caractérisation des Plantes aromatiques et médicinales (PAM) et des produits de l'agroalimentaire au travers des mélanges complexes volatils qui en sont issus. Ces mélanges complexes sont des huiles essentielles, des hydrolats, des extraits aux solvants et des fractions volatiles. Les différentes étapes de la séquence analytique ont été examinées à savoir, le choix des végétaux et leur échantillonnage, la préparation de l'échantillon, son analyse proprement dite, l'interprétation des résultats au moyen de l'outil statistique et leur valorisation au travers de la recherche de principes actifs. La première partie vise à caractériser les huiles essentielles, les hydrolats, les extraits aux solvants et les fractions volatiles issus de PAM et ainsi que les arômes des huiles d'olives et de jus d'agrumes. Pour cela, nous avons examiné les potentialités de méthodes dites alternatives à l'hydrodistillation, méthode conventionnelle pour l'obtention des huiles essentielles et des hydrolats, telles que l'extraction assistée par micro-ondes et la MicroExtraction en Phase Solide. L'analyse proprement est réalisée au laboratoire CPN à l'aide de techniques chromatographiques telles que la Chromatographie en Phase Gazeuse (CPG) pour la quantification et la CPG couplée à la Spectrométrie de Masse (CPG-SM) pour l'identification des constituants des mélanges. Nous avons optimisé la séquence analytique en utilisant la complémentarité des techniques telles que la chromatographie sur colonne, l'utilisation de la SM en mode ionisation chimique et de la Résonance Magnétique Nucléaire pour l'identification de molécules absentes des bibliothèques de références. La deuxième partie concerne le développement d'un axe de recherche nouveau qui vise à mettre en évidence des principes actifs au travers de l'étude des propriétés antibactériennes et antifongiques des huiles essentielles et des extraits de végétaux. Nous avons mis en évidence les propriétés biologiques d'huiles essentielles et d'extraits sur un certain nombre de bactéries impliquées dans des infections nosocomiales et alimentaires. La dernière partie développe les perspectives de travail qui visent à renforcer les travaux sur les PAM et sur les produits identitaires de l'agroalimentaire produits en Corse en explorant de nouvelles matrices d'études (fraction lourde) et de nouvelles techniques d'extraction. La valorisation des mélanges complexes issus des végétaux par la recherche de nouveaux antibiotiques surpassant les mécanismes de résistance des bactéries et de nouveaux antioxydants reste un challenge scientifique d'avenir.