The Study On The Effects Of Elicitor On The Synthesis Of Main Flavonoids And Their Bioactivity In Adventitious Roots Of Cajanus Cajan(Linn.)Millsp

Cajanus cajan(Linn.)Millsp is a homology of medicine and food leguminous plant with high medicinal value.Flavonoids extracted from pigeon pea has antioxidant,antimicrobial and anti-inflammatory activities.Adventitious root culture has the advantages of high efficiency,stable material sources,controllable culture conditions and high repeatability.methyl jasmonate and salicylic acid are two commonly used abiotic elicitors,which are widely used in cell culture of medicinal plants to increase the production of flavonoids.On the basis of adventitious root culture of pigeon pea,the adventitious root of pigeon pea treated with methyl Jasmonate and salicylic acid,the effects of elicitors on the synthesis of total flavonoids,genistein and apigenin from adventitious roots of pigeon pea and their mechanisms were studied.The biological activities of extracts from adventitious roots of pigeon pea were also studied..The main results were as followed:1.Methyl jasmonate and salicylic acid could promote the synthesis of total favonoid from adventitious root of pigeon pea and the effect was affected by concentration and time the growth inhibition of adventitious roots was the strongest.When treated with methyl jasmonate at 100μmol/L for 48 hours,the content of total flavonoids and genistein in adventitious roots was the highest,the content of total flavonoids was 75.33 mg/mL,1.87 times that of control group,and the content of genistein was 1385.91 μg/g,2.93 times that of control group.when the adventitious roots of pigeon pea were treated with 100 μmol/L methyl jasmonate for 96 hours,,the content of apigenin in adventitious roots of pigeon pea was 103.15 μg/g,which was 4.27 times higher than that of the control group.When the adventitious roots of pigeon pea were treated with 50 μmol/L salicylic acid for 48 hours,the content of total flavonoids,genistein and apigenin in adventitious roots reached the maximum.The content of total flavonoids in adventitious roots was 67.58 mg/g,which was 1.68 times of that in control group,the content of genistein in the adventitious root of pigeon pea was 542.07 μg/g,which was 1.74 times that of the control group,the content of apigenin was 83.96 μg/g,which was 2.48 times higher than that of the control group.2.The results of the study on the antioxidant system of adventitious root of pigeon pea during induction of elicitor showed that the contents of O2,H2O2and MDA increased in general and were significantly higher than those of the control group.Although the activities of antioxidant enzymes SOD,POD and CAT increased,the effects of reactive oxygen species could not be eliminated.During induction of elicitor,significant oxidative stress occurred,which led to the adventitious roots of genistein.Improvement of synthesis ability of secondary metabolites3.The effect of plasma membrane Ca2+influx on the induction process of elicitor was studied.Ca2+ antagonists can promote the biomass of adventitious root of pigeon pea.The synthesis of secondary metabolites in adventitious root of pigeon pea induced by elicitor will not be blocked by Ca2+ antagonists,and the induction effect does not depend on the presence of exogenous Ca2+ and Ca2+ concentration.4.The results showed that the extracts from adventitious root of pigeon pea induced by methyl jasmonate and salicylic acid had good bioactivity.The IC50 of DPPH free radicals in adventitious root extracts of pigeon pea were 0.378 mg/mL and 0.723 mg/mL which showed fairly DPPH scavenging ability.The extracts of adventitious root of pigeon pea treated with 100μmol/L methyl jasmonate for 48 hours and 50 μmol/L salicylic acid for 48 hours showed broad-spectrum bacteriostasis against Gram-positive bacteria(Staphylococcus aureus,Bacillus subtilis)and Gram-negative bacteria(Escherichia coli,Acinetobacter baumannii).The extracts of adventitious root of pigeon pea treated with salicylic acid and methyl jasmonate showed inhibitory effects on mouse melanoma cells proliferation and significantly greater than the untreated control group.The IC50 of the extracts were 51.22 μg/mL and 199.32 μg/mL.Simultaneous,the two extracts of adventitious root had certain effect on inducing apoptosis.The apoptotic rates of mouse melanoma cells treated with 500 μg/mL extracts of adventitious root reached 33.06%and 22.57%.In conclusion,elicitor methyl jasmonate and salicylic acid can promote the synthesis of Flavonoids in adventitious root of pigeon pea,which may be due to oxidative stress during elicitors induction.The extracts from adventitious root of pigeon pea induced by elicitors had good biological activity.This study will provide basic data and theoretical basis for large-scale adventitious root culture system of pigeon pea and has good application prospects.