Polyphenol Extraction From Berries And Leaves Of Three Kinds Of Seabuckthorn And Its Activity Of Antioxidant And Antiproliferative Against HepG2 Cells

Berries and leaves of seabuckthorn?Hippophae rhamnoides L.?are rich in polyphenols,however,the research and development is obviously insufficient.In this study,the berries and leaves of three kinds of seabuckthorn,H.rhamnoides subsp.sinensis?Sinensis?,H.rhamnoides subsp.tibetana?Tibetana?and H.rhamnoides subsp.neurocarpa?Neurocarpa?were selected as the assay material.Based on the optimization of the polyphenol extraction techniques of berries and leaves,the composition and content of polyphenols extracts were analyzed.The antioxidant activity and the antiproliferative capacity of polyphenols extracts were evaluated in vitro and on liver cancer HepG2 cells.The results showed as below:1.The polyphenol extracting techniques from berries and leaves of Sinensis were optimized as:ethanol concentration at 51%,ultrasonic temperature at 80^oC,ultrasonic time for 30 min,and ethanol concentration at 63%,solid-liquid ratio 1:58,ultrasonic time for 36min.Under optimal conditions,the polyphenol yields of berries and leaves reached 3.04 mg/g and 30.01 mg/g.2.The berries and leaves of Sinensis had the highest total phenolic content,was up to6.1 mg/g and 32.45 mg/g,which were 1.5 times and 2 times higher than that of Tibetana and Neurocarpa.Eleven phenols were identified,vanillic acid,ferulic acid,gallic acid,caffeic acid,protocatechuic acid,p-coumaric acid,rutin,quercetin,myricetin,kaempferol and isorhamnetin in berries and leaves of three kinds of seabuckthorn.There was a significant difference of identified phenols between berries and leaves,and among three kinds.The leaves had more phenol composition,and Sinensis had more phenols content.3.The polyphenol extracts of three kinds of seabuckthorn berries and leaves effectively removed ABTS,DPPH,O₂^-radicals and had a stronger reducing ability.The removal ability of Sinensis showed the best,the clearance rate reached 92%and 70%when the extracts concentration of berries and leaves was at 4 and 0.4 mg/mL.In addition,the in vitro antioxidant activity of the extracts from berries was significantly higher than that of the control V_E.The antioxidant capacity of the extracts from leaves was significantly stronger than that from berries,and was equivalent to the control butylated hydroxy toluene?BHT?.4.The leaves polyphenol extracts of three kinds of seabuckthorn also had a better cellular antioxidant activity,Neurocarpa showed strongest,followed by Sinensis,the CAA values reached 661.8 and 603.3??mol QE/100g?,respectively.The CAA activity of Neurocarpa was equivalent to of the control Vc under the treatment without PBS washed.For berries,the CAA values of Neurocarpa and Sinensis were about twice and 1.5 times higher than that of Tibetana.The CAA activity of berries was significantly stronger than control V_E,and cellular antioxidant capacity of leave extracts was significantly stronger than that of berries.5.The polyphenols extracts from leaves and berries of three kinds of seabuckthorn effectively inhibited the proliferation of HepG2 cells.The anti-proliferative ability of Sinensis showed the strongest,the cell proliferation rate was only 39%when the extracts concentration of leaves and berries at 1.2 and 12?mg/mL?,respectively.In addition,effect of The leaves polyphenol extracts had a stronger anti-proliferative activity than that of berries.It is suggested that the berries and leaves of three kinds of seabuckthorn are rich in polyphenols,and the content of phenols in the leaves is significantly higher than that of berries.In addition,the polyphenol extracts from seabuckthorn berries and leaves have a better free radical scavenging effect,cell antioxidant activity and a stronger inhibition effect on the proliferation of HepG2 cells.The leaves extracts show a better of the antioxidant and anti-proliferative ability than berries.