Antifungal activity of hydrocolloid nano encapsulated Carum copticum essential oil and Peganum harmala extract on the pathogenic fungi Alternaria alternata

Nano encapsulated naturally derived antimicrobial compounds are nowadays under great attention because of their ability to enhance the efficacy of loaded therapeutics. Alternaria alternata is a fungal pathogen related to the sever disease of tomato plants called early blight which causes high economic losses in tomato production every year and worldwide. Plant compounds such as Carum copticum essential oil (CEO) and Peganum harmala extract (PE) are known to possess considerable antifungal properties. This study was set to investigate the coencapsulation of CEO and PE in chitosan nanoparticles in order to enhance antifungal activity and stability of the oils against A. alternata. The prepared nanoparticles were characterized by different analytical methods followed by their in-vitro and in-vivo antifungal evaluations. The obtained results indicated that the particles are spherical in shape with positively charged surface and the average size of 100 nm. In-vitro results showed that chitosan nanoparticles loaded with CEO-PE at a concentration of 200 ppm, have a complete inhibitory effect, while the bare essential oils and extracts have an inhibitory effect at concentrations of 500 and 750 ppm, respectively. Also the in-vivo studies revealed that the PE-CEO encapsulated nano particles have the therapeutic efficacy equal to that of commercial fungicide of chlorothalonil. These findings demonstrated the promising role of CEO-PE loaded chitosan nanoparticles for success controlling of pathogenic fungi in both in-vivo and in-vitro conditions.