Study On Chemical Constituents Of The Ethyl Acetate Part Of Alpinia Oxyphylla Miq.and Their Biological Activity

Background: Fructus Alpinia oxyphylla is the dry ripe fruit of Alpinia oxyphylla Miq.,which belongs to the genes Alpinia in family Zingiberaceae,is mainly distributed in Guangdong,Guangxi,Hainan,and Fujian provinces of China.It is a genuine medicinal materials of Hainan province,which is known as the four southern medicines in China together with Areca catechu L.,Amomum villosum Lour.and Morinda officinalis How..It has been widely used as nourishing spleen and stomach,antidiarrbea,anti-salivation,antipolyuria and aphrodisiac traditional Chinese medicine.In our study,the chemical constituents of the ethyl acetate fractions of 95% ethanol extract from A.oxyphylla were studied,and the anti-tumor and antibacterial activities were evaluated.Objective: The aim was to study the chemical constituents of ethyl acetate fraction of A.oxyphylla and determine the compounds it contained.Furthermore,pharmacological activities of novel compounds were evaluated to pave the way for further research and application of the medicinal value of the plant.Methods:Silica gelcolumn chromatography,MCI column chromatography,Sephadex LH-20 gel column chromatography and semi preparative liquid method were employed for the isolation and purfication.The structure of the separated compounds was identified by combining the determination of physical and chemical constants and modern spectroscopic techniques.The anti-tumor of the different polar parts and monomer compounds isolated from A.oxyphylla were tested by CCK-8 method and antibacterial activity by inhibition of mycelial growth rate method.Results:(1)From the ethyl acetate fraction of A.oxyphylla,18 compounds were isolated and 17 compounds were identified.Among these compounds,it is the first time that 9 compounds were obtained from the plant and 8 were from the genus.It included 7 diphenylheptanes,2 flavonoids,4 terpenoids and 4 others.They were respectively phthalic acid-bis(2?-ethyl heptanyl)easter(compound 1),1-(4?-hydroxyp henyl)-7-(3?-methoxy-4?-hydroxyl)-4-ene-3-heptanone(compound 2),yakuchinone A(compound 3),(E)-1-(4-hydroxy-3-methoxy-phenyl)-7-(4-hydroxy-phenyl)-hept-4en--3-one(compound 4),5-dehydroxy-hexahydrodemethoxycurcumin-B(compound 5),5-hydroxy-7-(4″-hydroxy-3″-methoxyphenyl)-1-phenyl-3-heptanone(compound 6),dihydrogingerenone B(compound 7),tectochrysin(compound 8),chrysin(compound 9),oxyphyllenone B(compound 10),(1R,4R,10R)-1β,4α-dihydro-xy-11,12,13-trinor-5,6-eudesmen-7-one(compound 11),1β,4β,7β-trihydroxyeudesmane(compound 12),bullatantriol(compound 13),1,5-epoxy-3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphen yl)-7-(4-hydroxy-3-methoxyphenyl)heptanes(compound 14),fifteen-methyl-tetracon tane(compound 15),1-tetratriacontanol(compound 16),daucosterol(compound 17).(2)The anti-tumor activity of the different polar parts of A.oxyphylla(petroleum ether fraction,ethyl acetate fraction,n-butanol fraction,water fraction)and compounds isolated were tested using A549,MCF-7,SW620,SMMC-7721 and 4T1 cells as receptor cells by CCK-8 assays.The results showed that the petroleum ether and ethyl acetate fraction had better anti-proliferative effects than others,which exhibited a good anti-tumor activity against five tumor cells in a concentration-dependent manner within the concentration range(25-800μg/m L).The preliminary screening results of the compounds showed that almost all compounds inhibited the cell proliferation except for compound 11,compound 15 and compound 18.Among them,diphenylheptane compounds had strong inhibitory effects on cell proliferation.(3)Fusarium graminearum,Alternaria alternate,Fusarium solani and Fusarium oxysporum were used as tested strain.The antibacterial activity of the different polar parts of A.oxyphylla(petroleum ether fraction,ethyl acetate fraction,n-butanol fraction,water fraction)and compounds isolated were evaluated by the inhibition of mycelial growth rate method.The results showed that the fractions of petroleum ether and ethyl acetate had an obvious antibacterial activity.The ethyl acetate extract exhibited a stronger antibacterial activity in a concentration-dependent manner within the concentration range tested(0.0625-1.0 mg/m L)and the Fusarium graminearum was inhibited most obviously.The preliminary screening results showed that all compounds had certain antibacterial effects except compound 15.Compound 5 showed the strongest antibacterial activity and the inhibition rate reached 61.6%.