Myrtus communis L. is one of the important aromatic and medicinal species from the Mediterranean area. It is used in various fields such as culinary, cosmetic, pharmaceutical, therapeutic, and industrial applications. Thus, a Box–Wilson experimental plan was used in this study to select the optimal operating conditions in order to obtain high volumes of essential oils. The factorial design method was applied to evaluate at an industrial scale the effect of major process variables on the essential oil extraction from Myrtus communis L. herbs by the steam distillation method. The input variables considered as significant operating conditions were: X₁—boiler occupancy rate (boilers were filled to 50%, 75%, and 100%), X₂—distillation duration (distillation was continued 60, 75, and 90 min), and X₃—particle size (herbs were cut in sizes of 10, 20, and 30 mm via guillotine). The dependent variable selected, coded as Y, was the essential oil volume obtained (mL). The steps of the classical statistical experimental design technique were complemented with the Taguchi method to improve the extraction efficacy of essential oil from Myrtus communis L., and the optimum parameter conditions were selected: boiler occupancy rate 100%, distillation duration 75 min, and particle size 20 mm. Following the optimum parameters, the GC-MS assay revealed for the Myrtus communis L. essential oil two predominant components, α-pinene—33.14% and eucalyptol—55.09%.

Fusarium oxysporum and Pestalotiopsis funerea are the most common fungal disease agents of conifer seedlings causing root rot and shoot or tip blight diseases. In this study, chemical compositions and antifungal activities of essential oils of fennel (Foeniculum vulgare Mill.) and laurel (Laurus nobilis L.) were determined against root rot and wilt disease agents F. oxysporum and P. funerea in vitro conditions. Chemical compositions of essential oils were determined by using GC-MS analysis. Antifungal volatile phase effects of essential oils were determined on inhibition of mycelial growth in vitro conditions by using different concentrations. The effect of most effective concentrations of essential oils on the morphology of fungal hypha was also determined by using light microscope. GC-MS analysis of essential oils of laurel and fennel plants revealed that eucalyptol (46.97%) and α-terpinyl acetate (19.82%) were major components of laurel; trans-anethole (82.44%) and limonene (5.18%) were major components of fennel essential oils. Volatile phase effects of fennel and laurel essential oils were found to completely inhibit mycelial growth of F. oxysporum at 30.0 and 50.0 µl petri-1 concentrations, respectively. Complete growth inhibition of P. funerea by essential oil of fennel and laurel were observed at relatively lower concentrations (20.0 and 25.0 µl petri-1 concentrations, respectively). Light microscopic observations on hyphae, exposed to volatile phase of the most efficient concentrations of essential oil, revealed considerable structural deformations such as cytoplasmic coagulation, vacuolations and protoplast leakage. In conclusion, our results suggest that essential oils have the potential for use in control of fungal diseases of conifer plants.

Amaç: Bu çalışmada, farklı azot dozlarının (0, 3, 6, 9, 12 kg da-1), Hatay koşullarında yetiştirilen kişniş (Coriandrum sativum var. vulgare) popülasyonunda taze herba uçucu yağ bileşenleri üzerine etkinliği araştırılmıştır. Yöntem ve Bulgular: Kişniş tohumlarının (29 Ocak 2020) tarlaya ekimi gerçekleştirilmiştir. Azot dozlarının yarısı ekimle birlikte, diğer yarısı ise bitkiler 5–10 cm boylandığında uygulanmıştır. 13 Nisan 2020 tarihinde bitkiler hasat edilmiştir. Taze herba örnekleri 3 saat süre ile Clevenger tipi aparat kullanılarak su buharı distilasyon ile uçucu yağları elde edilmiş ve elde edilen uçucu yağ bileşenlerine GC-MS ile bakılmıştır. Sonuçlara göre ana bileşenler; kontrol parseli ve bütün gübre dozları için; 2-Decenal, 2-Dodecanal, Decanal, Cyclodecanol, 13-Tetradecanal, Dodecanal, 1-Decanol, Undecanol, 2-Tridecenal, olarak tespit edilmiştir. Genel Yorum: Gübre dozlarının artması ile birlikte tespit edilen ana bileşenlerin oranlarının bazılarında artmalar, bazılarında azalmalar gözlemlenirken bir kısmında ise büyük bir değişim gözlemlenmemiştir. Çalışmanın Önemi ve Etkisi: Bu çalışma ile kişniş taze herba uçucu yağındaki etken maddeleri oluşturan bileşenlerin farklı azot dozuna tepkisi belirlenerek en uygun azot dozunun belirlenmesi sağlanmıştır. Bu yönüyle kişniş taze herba uçucu yağı bileşenlerinin antimikrobiyal çalışmalarda kullanılabilirliği, ayrıca farklı bitkilerin uçucu yağ bileşenleri üzerine azot uygulamalarının etkileri konularında yapılacak çalışmalarla da desteklenebileceği düşünülmektedir.