Efficacy of essential oil of zingiber officinale (rosc) in preservation of orange (citrus sinensis (l.)osbec fruit against rotting fungi

Pramila Tripathi

The antifungal activity of essential oil of Zingiber officinale was tested agianst the post harvest fungal species of oranges viz., Penicillium italicum, P. digitatum, Geotrichum citri, Alternaria alternata, Colletotrichum gloeosporioides and Phomopsis citri. The oil was standardized through physicho-chemical and fungitoxic properties. The yield of oil was 1.2% .The specific gravity of the oil was 0.890. The saponification value was 23.84. The ester value was 19.36.The acid value was 4.48.The MIC of the oil was 100ppm against P. italicum and P.digitatum, 200ppm against G. citri and 500ppm against A.alternata, C.gloeosporioides and P.citri. The nature of toxicity of the oil was found to be static at the respective MICs of the oil against different fungi. At higher concentration the nature of toxicity of the oil was turned to cidal in nature. The oil was found to be thermostable up to 80˚ C of temperature.The oil retained its fungitoxicity up to 2 years. The fungitoxicity of the oil tolerated the higher inoculums densities of all the tested post harvest fungi. The oil was found to be more efficacious than some prevalent synthetic fungicides on the basis of having lower MIC as compared to synthetic ones.

Download PDF: