Evaluation of the chemical characteristics and control of the growth of spoilage fungi causing rot in grape fruit using ginger essential oil (Zingiber officinale)

The growth of fungal pathogens on the grape fruit causes a decrease in its quality and shelf life. In this study, the antifungal activity of ginger (Zingiber officinale) essential oil was investigated against fungal pathogens that cause spoilage in grape fruit. Ginger essential oil was extracted using hydrodistillation method and the content of total phenol, total flavonoid, antioxidant activity based on the inhibition of DPPH and ABTS free radicals and its antifungal activity against Aspergillus niger, Rhizopus stolonifer and Botrytis cinerea strains based on disc diffusion agar, well diffusion agar, minimum inhibitory concentration, and minimum fungicidal concentration were evaluated. The results showed that ginger essential oil has 89.80 mg GA/g total phenol and 38.60 mg QE/g total flavonoid. Its antioxidant activity against DPPH and ABTS free radicals was 73.45 and 66.53 μg/ml, respectively. The results of antifungal activity showed that A. niger and B. cinerea were the most sensitive and resistant fungal strains to essential oil, respectively, and the diameter of the inhibition zone in the disc diffusion and well diffusion agar methods, the minimum inhibitory concentration, and the minimum fungicidal concentration for the A. niger strain was equal to 13.90 mm, 14.50 mm, 8 mg/mL and 64 mg/mL, respectively. In general, ginger essential oil can be used as an antioxidant and antimicrobial agent to increase the shelf life of agricultural products.