Extraction,antimicrobial And Insecticidal Activities Of Citrus Essential Oil

Citrus is one of the most important agricultural products in the world.More than 140 countries and regions around the world cultivate citrus.The planting area is more than 800 million hectares,and the output is more than 100 million tons.The trade value of citrus ranks No.1 in the world.Citrus peel,flowers and leaves contain essential oils,of which citrus peel essential oil is the world's largest production and consumption of natural plant essential oil,which has antioxidant,antibacterial and anticancer activities.Extraction and processing of citrus oil is a good way of comprehensive utilization of citrus resources.In this study,extraction technology and biological activity of citrus essential oil were studied.The citrus essential oil was processed by molecular distillation technology.The isolated components were tested for antimicrobial and insecticidal activity.The essential oils of Gannan navel orange leaves and pHysiological fruit drop were extracted.ChromatograpHy-Mass Spectrometry(GC-MS)was used to analyze the chemical constituents of all essential oils.The results are as follows:1.Molecular distillation technology was used to deal with cold pressed orange oil and cold pressed grapefruit essential oil to get light pHase and heavy pHase components.Gas chromatograpHy-mass spectrometry(GC-MS)was used to analyze their chemical composition.The light pHase of sweet orange oil contains 22 compounds,and the heavy pHase contains 40 compounds.Cold pressed grapefruit essential oil contains 35 compounds,and the light pHase contains 31 compounds.The results showed that the light and heavy pHase components of sweet orange essential oil had good antimicrobial effect on Escherichia coli,StapHylococcus aureus,Bacillus subtilis and Yeast,and the minimum inhibitory concentration(MIC)ranged between 0.78 and 3.125 ?L/mL.Different pH and temperature conditions have different effects on the antimicrobial effect of essential oil.Light pHase of grapefruit essential oil had better antibacterial effect on Escherichia coli,StapHylococcus aureus,Listeria monocytogenes and Salmonella enteritidis than cold pressed grapefruit essential oil,and the MIC values ranged between 25 and 100 ?L/mL.This research work can provide a scientific reference for the development of green,safe,efficient and environmentally friendly natural preservatives and antibacterial agents.2.The components collected under the condenser,light-pHase and heavy-pHase were obtained by using the molecular distillation technique.The chemical constituents were analyzed by GC-MS.A total of 50 compounds were identified from the American sweet orange essential oil components.There were 31 compounds in the essential oil of Gannan navel orange,and the main components were monoterpenes and sesquiterpenes.The results showed that the different fractions of the two kinds of essential oil prepared by molecular distillation had good fumigation activity against the workers of the red fire ants,and the total fumigation activity was in the order of: the components collected under the condenser > light pHase > heavy pHase.Fumigant activity of Gannan navel orange essential oil was stronger than that of American sweet orange essential oil.This study has a positive effect on the development of natural harmLess insecticides.3.The essential oil of Gannan navel orange leaves and pHysiological fruit drop were prepared by steam distillation,and their chemical constituents were analyzed.47 compounds of Ganan navel orange leaf oil were identified,accounting for 98.951% of the total oil,46 compounds were identified in pHysiological fruit drop essential oil,Accounting for 92.439% of the total oil.