Extraction And Characteristic Of Flavonoids From Citrus Reticulate

Citrus peel are rich in biological active substances, such as flavonoid, have a huge value. Currently, most research focused on study oxidation resistance, but rarely reported in antibacterial. In this study, the flavone compounds were extracted from citrus peel with a method of improved ethanol extraction, this study focus on the antimicrobial features of flavone to Staphylococcus aureus, E. coli, Aspergillus niger, Botrytis cinere, and Cladosporium fulvum, and enhance the inhibition capabilities. Observing the inhibition capabilities against bacteria of greenhouse tomato, explore its application prospect.In this study, the flavone compounds were extracted from citrus peel with a method of improved ethanol extraction, a low toxicity of ethanol extraction. The optimum extraction conditions were determined by orthogonal test. The minimum inhibition concentration(MIC) was test by agar diffusion method. The inhibition capabilities against bacteria and fungus were test by zone of inhibition. Observing the influence of different pH, temperature, metal ions on flavone’s inhibition capabilities, and compared the inhibition capabilities with chloro 3,5dimethylphenol p-Chloro-m-xylenol and Thiophanate-methyl. At last, we applied the flavone to the greenhouse tomatoas a bacteriostatic agent and observed its result.The optimum extraction conditions were determined by orthogonal test as follows:70% ethanol and the solid to liquid ratio 1︰20(g/m L) at 70 oC in 2 hours. The concentration of the flavone compounds were examined at 510 nm with the spectrophotometer. The results showed that the yield rate of flavone compounds to the raw materials reached to 2.938 mg/g, and the ethanol recovery ratio could be up to 94%.The inhibition of the flavonoids extracted against the growth of Staphylococcus aureus, E.coli, Aspergillus niger, Botrytis cinere, and Cladosporium fulvum was found. In addiction, p H and temperature of the flavonoids could affect the efficiency of the inhibition. The minimum inhibition concentration(MIC) was reduced by 20% with the ideal formulation of the extracted flavonoids, and the inhibition capabilities against Staphylococcus aureus, E. coli, Aspergillus niger, Botrytis cinere, and Cladosporium fulvum were increased by 17%, 27%, 25%, 28%, 19% respectively in the presence acidic pHand suitable temperature. The inhibition capabilities against bacteria and fungus were higher than that of chloro 3,5dimethylphenol p-Chloro-m-xylenol and Thiophanate-methyl at the equivalent concentration, particularly against bacteria.Copper and magnesium ions could enhance the inhibition function on bacteria and fungus respectively. The production of the greenhouse tomato were increased by 16.3% because of the flavone as aantimicrobial agent.The yield rate of flavone compounds to the raw materials reached to 2.938 mg/g,the ethanol recovery ratio could be up to 94%.The flavonoids can against the growth of Staphylococcus aureus, E. coli, Aspergillus niger, Botrytis cinere, and Cladosporium fulvum. The inhibition capabilities of ideal formulation of the extracted flavonoids is better than chloro 3,5 dimethylphenol p-Chloro-m-xylenol and Thiophanate-methyl. The flavonoids can against the growth ofBotrytis cinere, and Cladosporiumfulvum in the greenhouse, and can be developed as biological fungicide.