Study On The Isolation Of Psoralen From The Leaves Of Fig And Its Controlling Effect Against Cucumber Powdery Mildew Disease

Fig(Ficus carica Linn.),a small deciduous tree in the mulberry family Ficus,is a fruit tree widely distributed around the world.Fig fruits is rich in a variety of biologically active ingredients,and the leaves also contain a large amount of psoralen.Although psoralen has been used as a raw material for pharmaceutical production due to its significant pharmacological activity,a large number of fig leaves have not been effectively utilized.Existing research also suggests that fig leaf extract has potential anti-plant pathogenic effect.In this paper,fig leaves are used as raw materials.First,microwave-assisted cation exchange resin extraction technology(MACERE)is used to efficiently extract psoralen(PSO)from fig leaves.At the same time,strong acid cation exchange resin is used to catalyze psoralen to psoralen.After conversion,further increase its content,and then use macroporous adsorption resin to enrich and separate psoralen from the extract of fig leaves.Next,the inhibitory effect of purified psoralen on the pathogen of cucumber powdery mildew was studied.The results of this paper can provide theoretical basis and technical support for the rational development and utilization of fig leaf resources.The main research results are as follows:1.The microwave-assisted cation exchange resin extraction technology(MACERE)is used to efficiently extract psoralen(PSO)from fig leaves.At the same time,the strong acid type cation exchange resin is used to promote the catalytic conversion of psoralen to psoralen.Factor test and Box-Behnken design(BBD)combined response surface analysis optimized the experimental conditions.A comparative study of ten cation exchange resins of 001×7,D072,110,D001-CC,NKC-9,D151,002×7,D113,DLT,and D061 shows that seven types except D113,DLT,and D061 Ion exchange resins have good catalytic conversion effect,and the effect of D072 type ion exchange resin is the best,so D072 type ion exchange resin is selected as the preferred resin,and its addition amount is 2%of the mass fraction of the solution.Using D072 ion exchange resin as the preferred resin,the best extraction conditions were obtained by BBD design and response surface analysis:liquid-solid ratio:20 mL/g,ethanol concentration:60%,microwave temperature:60?,extraction time:10 min,Microwave power:600 W.Under the optimal extraction conditions of MACERE,the yield of psoralen(PSO)was 38.54±0.08 mg/g.Compared with the traditional heat reflux extraction method(HRE),microwave extraction(ME),microwave assisted hydrochloric acid extraction method(MAHAE),MACERE extraction of fig leaf psoralen is a green extraction method with the advantages of short extraction time and high yield.2.The macroporous adsorption resin is used to efficiently and rapidly separate and extract psoralen(PSO)from the fig extract.Eight different types of macroporous adsorption resins of HP20,AB-8,LSA-10,HPD400,X-5,HPD826,D101 and NKA-9 were selected for enrichment and separation.The results showed that the above eight macroporous adsorption resins were complementary Osteolipin has a good effect of enrichment and separation,and the effect of enrichment and separation by X-5 macroporous adsorption resin is the best.After enriched and purified by X-5 macroporous adsorption resin,the purity of psoralen increased from 3.52%to 87.2%,an increase of 24.8 times.3.The inhibitory activity of psoralen enriched by macroporous adsorption resin against cucumber powdery mildew pathogen in vitro was studied.The experimental results show that in the in vitro conidial germination experiment,the concentration of 1.0 mg/L psoralen solution on the germination of conidia can reach 69.3%,and the concentration of psoralen at a concentration of more than 5.0 mg/L Lipid inhibited the germination of conidia in vitro over 95%.In the pot experiment,psoralen with a concentration of 5.0 mg/L can alleviate and contain the diseased cucumber seedling leaves.