Investigating the Essential Oil Composition of Rosmarinus officinalis Before and After Fertilizing with Vermicompost

Vermicomposting is more akin to livestock production, since the process relies not only on microorganisms, but also on worms that digest raw organic materials and excrete them as nutrient-rich castings. Earthworms and microorganisms join forces in a bio-oxidation and stabilization process that dose not have a thermophilic stage. The earthworms are the agents of turing, fragmentation and aeration. Vermicomposting is better than other ways of managing solid wastes, like traditional composting and landfilling, which are expensive and may lead to leaching of toxic compounds. Rosmarinus officinalis essential oil is used as a preservative in the food industry due to its antioxidant and antimicrobial properties. In this study, the essential oil of this plant was examined for any changes after a period of fertilization by vermicompost in comparison to the its essential oils without fertilization. GC-MS was used for these evaluations. The essential oil was collected by hydrodistillation with a yield of 1.7 % (w/w). Of the 32 major compound present in essential oil of Rosmarinus officinalis, five of them which are mainly phenolic compounds, showed an increase in the concentration, while other componds was not changed significantly. According to this study, the ability of production of phenolic compounds in organic form can be improved by vermicompost fertilizing.