Studies On The Extraction Purification And Antifungal Activities Of Total Flavonoids In The Leaves Of Endangered Elaeagnus Mollis Diels

Elaeagnus mollis(Elaeagnus mollis Diels)which belongs to Elaeagnaceae (Elaeagnus)is an endangered perennial arboreal or shrubby plant and a national second-class key protected rare species in China. The researches indicate that the leaves of Elaeagnus mollis Diels are rich in flavonoids,but the studies of this aspect are very few in present.Taking Elaeagnus mollis as the research object, ultrasound-assisted extraction process, separation and purification process and antibacterial activity of the total flavonoids in Elaeagnus mollis leaves were studied in this thesis. The results are as follows:(1) Ethanol as extraction solvent was used. The ultrasound- assisted method was applied to extract flavonoids from the leaves of Elaeagnus mollis Diels leaves. According to the single and orthogonal experiments,the optimum conditions were found. Ethanol concentration 60%, ratio of material to liquid 1:30, extraction temperature 60℃,extraction time 30min.In this four factors, The influence function is Ethanol concentration>ratio of material to liquid>extraction time>extraction temperature.(2) The static adsorptive and desorptive capacities of 4 types of macroporousresins (AB-8,D4020,S-8,X-5) with different physical properties for flavonoids in the extract were determined to find a suitable resin and obtain its optimum technical conditions.The results indicated:AB-8 was the best absorbent of the total flavonoids in Elaeagnus mollis leaves. The optimum technical conditions were: the pH value of extracts was 3.0-4.0,the best ratio of absorbing solution and resin was 6:1,the current velocity was 2ml/min,the eluting reagent was 60% ethanol,the eluting velocity was 2ml/min,the volume of the eluting solution and was 3BV.(3)The antifungal activities of the total flavonoids in different polar fractions of Elaeagnus mollis leaves on bacteriostasis and cytospora spp were screened by the methods of agar diffusion test and growth rate test.The results show that the inhibitory effect of the total flavonoids in different polar fractions is most obvious on Bacillus subtilis and all of them in a dose-dependent manner.the inhibitory effect of the three polar fractions is Chloroform fraction>EtOAc fraction>n-BuOH fraction.The total flavonoids in different polar fractions exhibited variable inhibitory effects against cytospora spp. the inhibitory action of the flavonoids in Chloroform fraction is the most obvious and that in EtOAc fraction is weak, but all of them are in a better dose-dependent manner.It is possible because that the ingredients and the quantities of the flavonoids are different in the three fractions.