| The antifungal activity of the Yucca gloriosa L. extracts were tested with Penicillium italicum, Penicillium dititatum, Botrytis cinerea Pers., Botrytis cinerea Pers., Botrytis allii Munn. The results were as follows:1 Yucca gloriosa L. leaves were extracted by 60% (v/v) ethanol, then its antifungal activity was determined by filter-disk diffusion method, the minimal inhibition concentration (MIC) of 60% ethanol extracts was assayed by use of agar dilution method, and the influence of temperature and ultraviolet radiation on its antifungal activity was studied in this paper. The results showed that the antifungal effect of 60% ethanol extracts on Botrytis cinerea Pers (isolated from garlic bolt), Botrytis allii Munn, Penicillium dititatum and Botrytis cinerea Pers (isolated from grape) was significant, while no effect on Penicillium italicum. The MIC of 60% ethanol extracts to Botrytis cinerea Pers (isolated from garlic bolt), Botrytis allii Munn, Penicillium dititatum and Botrytis cinerea Pers (isolated from grape) was 0.0625g/mL, 0.125g/mL, 0.125g/mL and .0.25g/mL, respectively. The effect of different concentrations of 60% ethanol extracts on Penicillium dititatum was significantly different (P<0.05), the effect of high temperature and ultraviolet radiation on Penicillium dititatum was not significantly different (P>0.05).2 The antifungal components were extracted from Yucca gloriosa L. by traditional extraction, microwave irradiation extraction and ultrasonic extraction. The optimum extraction conditions of antifungal substance were confirmed according to a L9 (34) orthogonal experiment. The result showed that the optimum extraction conditions of traditional extraction were ethanol 45%, 1g:15mL for ratio of solid to liquid, extracting temperature 70℃, extracting time 2h; the optimum extraction conditions of microwave irradiation extraction were ethanol 45%, 1g:15mL for ratio of solid to liquid, power 320W, extracting time 3min; the optimum extraction conditions of ultrasonic extraction were ethanol 45%, 1g:15mL for ratio of solid to liquid, extracting temperature 50℃, extracting time 10min. The diameter of antifungal circles of 1g/ml Yucca gloriosa L. extracts from traditional extraction, microwave irradiation extraction, ultrasonic extraction against Penicillium dititatum were 15.8mm,22.6mm and 24.3mm , respectively. Microwave irradiation extraction and ultrasonic extraction have the advantage of extracting temperature low and extracting time short over traditional extraction.3 In acute toxicity test, no visully toxic symptom was observed and no death occurred in rats. The medium lethal dose of daylily extracts on ICR rats was more than 15000g/kg·bw, which indicated Yucca gloriosa L. extracts was actually no toxicity according the standard of toxicity grade classification.4 In this paper, the inhibitory effect of Yucca gloriosa L. extracts on the decay caused by Botrytis cinerea Pers (isolated from garlic bolt) and Botrytis allii Munn was studied at ambient temeperature. The results showed that the inhibitory effect of Yucca gloriosa L. extracts on the decay caused by Botrytis cinerea Pers (isolated from garlic bolt) and Botrytis allii Munn were significant, the invasion of the two fungus was inhibited efficiently by 2.5g/L,5g/L,10g/L Yucca gloriosa L. extracts and decay of garlic bolt was reduced, the best effect was attained by 10g/L in this three treatments.5 To alleviate the infection of Penicillium dititatum, the effect of different concentrations of Yucca gloriosa L. extracts (2.5g/L,5g/L,10g/L,15g/L) on pathogenicity of Penicillium dititatum and the inhibitory effect of Yucca gloriosa L. extracts on the oranges decay were studied in this paper. The results showed that the pathogenicity of Penicillium dititatum and the decay of oranges were inhibited obviously by 2.5, 5, 10 and 15g/L Yucca gloriosa L. extracts treatment in vitro, among them, the inhibition of pathogenicity of Penicillium dititatum by 10 g/L Yucca gloriosa L. extracts treatment was significant (P<0.05), the inhibitory effect of 5g/L Yucca gloriosa L. extracts on the decay of oranges was significant (P<0.05). 6 The results showed that petroleum ether extract, trichloromethane extract and ethyl acetate extract have no effect on fungus,though the antifungal effect of butyl alcohol extract (0.05g/mL) on Botrytis allii Munn ,Penicillium dititatum and Botrytis cinerea Pers isolated from garlic stem was significant;the diameters of antifungal circles of them were 13.5mm,19.6mm,20.7mm, respectively. After separation two times, the diameters of antifungal circles of butyl alcohol extract(10mg/mL) against Botrytis allii Munn ,Penicillium dititatum and Botrytis cinerea Pers isolated from garlic stem were 16.2mm,22.3mm and 24.2mm. Through the qualitative identity of active component, the result showed that the flavone, organic acid and saponin were involvd in the active component; but there was no alkaloid, hydroxybenzeneand and anthraquinone in the active components.
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