Study On The Component Analysis And Efficacy Relationship Of Malus Pumila Flowers

Malus pumila belongs to the Rosaceae family.The main chemical components of in its flowers are dihydrochalcone such as phlorizin and phloretin,and flavonoids such as quercetin,kaempferol and rutin.M.pumila flowers tea has the function of relieving neuralgia,liver spots,treatment of dark spots,pimples,acne,assisting digestion,protecting the liver and other properties.This paper reviews the knock-out technology,and summarize its the advantages and disadvantages of knock-out technology by consulting literature.In this paper,the antioxidant and tyrosinase activity of M.pumila flowers were studied by spectrum-effect relationship and component knock-out method in vitro.The compounds that could activate or tyrosinase activity were screened out.Their structures were identified with the high resolution mass spectrometry.The specific chromatograms were established by HPLC method and the activity of antioxidant and tyrosinase were assayed in vitro.Chromatographic peaks P34,P35,P38,P39,P44,P45 and P49 were identified as phloridzin,hyperoside,kaempferide,astragalin,afzelin,quercetin and kaempferol by high resolution mass spectrometry method.The antioxidant activity and tyrosinase activity of different components in M.pumila flowers were determined in vitro.The results showed that when the concentration was 1 g/mL of sample(equivalent to raw material),the target components P15,P29,P32,P35(hyperoside),P36,P37,P38(kaempferide),P39(astragalin),P42,P44(afzelin),P48 and P49(kaempferide)could scavenge DPPH free radicals and P7,P15,P29,P32,P34(phloridzin),P36,P37,P40,P41,P42 and P45(quercetin)could scavenge ABTS free radicals.The target components P29,P32,P36,P37,P39,P40,P41,P42,P45(quercetin),P48 and P49(kaempferide)could activate tyrosinase,and P7,P15,P34(phloridzin),P35(hyperoside),P38(kaempferide)and P44(afzelin)could inhibit tyrosinase.Spectrum-effect relationship of M.pumila flowers in different batches were established by partial least squares method.The results showed that the scavenging capacity of P35(hyperoside)and P38(kaempferide)on DPPH free radicals were consistent with the spectrum-effect relationship.The scavenging capacity of P34(phloridzin)and P45(quercetin)on ABTS free radicals were consistent with the spectrum-effect relationship.The activation effect of P45(quercetin)on tyrosinase was consistent with the spectrum-effect relationship.The inhibitory effect of P34(phloridzin),P35(hyperoside)and P38(kaempferide)on tyrosinase were consistent with the spectrum-effect relationship.Secondly,the dynamic changes of secondary metabolites in M.pumila flowers were studied by high performance liquid chromatography-ultrasound.On the third day after the bud appeared(March 28,2018),the total content of phlorizin,astragalin and afzelin in M.pumila flowers reached the highest level(176.74 mg/g).Along with the fruit maturation,the total content of the aforementioned chemicals decreased.The content of astragalin and afzelin showed a downward trend after the 7th day after the bud appeared(April 1),while the content of phlorizin showed an upward trend after the 8th day after the bud appeared(April 2).Finaly,the method of ionic liquid-ultrasound assisted extraction coupled with [BMIM]Br/methanol solution was used.With aid of response surface design,its optimal condition was obtained with the following parameters: 70 mesh powder,0.52 mol/L of extract concentration,60 min as the ultrasonic time,1:100 as the solid-liquid ratio and 7000 r/min as centrifugal speed.Under the optimum conditions,the total content of phlorizin,astragalin and afzelin was 181.03 mg/g.After the addition of ionic liquid,the efficiency of extraction of phlorizin,astragalin and afzelin in M.pumila flowers could increase by 25.4%.