Tgp chiDitffc lieu, tap 18, so 1/2013 (Trang 26 - 31)
TAC DUNG CHONG OXY H 6 A THEO HX/dNG B A O V j G A N CUA POLYSACCHARID C H I ) 6 T TU" N A M THU'ONG HOANG
Nguyin Thi Thu Huffng, Ngd Quic Hfn
Trung Tdm Sdm vd Dugc lieu TP. Hi Chi Minh- Vi^n Dugc USu (Nhan bii ngay 04 thing 01 nam 2013)
Summary
Antioxidant Activity and Hepatoprotective Effect of Crude Polysaccharide Extracted from Pheltinus tiittais Phellintts linteus (Berlceley & M. A. Curtis) is a medicinal mushroom tliat lias been practicej in oriental countries for centuries to prevent ailments. Recently, the in vitro antioxidant activity and hepatoprotective effect of ethanol extract and aqueous extract of Pheltiims linteus on cyclophosphamide-induced oxidative stress were determined. The study was performed to investigate the in vitro antioxidant activity of polysaccharide and tractionated extracts of Phellinus linteus. For in vivo study, cyclophosphamide-injected mice were used to investigate the hepatoprotective effect of crude polysaccharide. Crude polysaccharide Irom Phellinus linteus had free radical scavenging activity on DPPH test and anti-lipid peroxidation effect on malonyl dialdehyde (MDA test) more typical than other Iractionated extracts. Crude polysaccharide at the oral dose of SO mg/kg for S days had no effect on the increase of hepatic MDA content and the decrease of hepatic glutathione in cyclophosphamide-injected mice. Crude polysaccharide at the oral dose of 100 mg/kg alleviated the increase of hepatic MDA and restored the decrease of hepatic glutathione caused by cyclophosphamide. The study revealed that crude polysaccharide irom Phellinus linteus showed the antioxidant activity and the hepatoprotective effect against cyclophosphamide-induced liver damage via increasing endogenous hepatic glutathione.
Keywords: Phellinus linteus, crude polysaccharide, cyclophosphamide, antioxidant activity, hepatoprotective eSecL 1. DJt van a l Phellinus sp. co tac dung lam giim s\f pliSt O Trung Quoc, nSm tliu<7ng lioang triin u, lam giam su tang tiSu ciu va lam tSng (Phellinus linteus Berkeley & M. A. Curtis, nhe so lugng Mng cau, hemoglobin, Hymenochaetaceae) dugc gpi la Song-gen, a hematocrit cr nhirng chuot bi gay ung thu Han Qu6c la Sang-hwang, va 6 Nhat la th\rc nghiem sarcoma 180 [3]. Ngoai ra, cao Meshimakobu hay Meshuna Reishi [9]. NSm nudc Phellinus sp. co tac dung bio v$ gan, thugng hoang dS dugc ghi nhan co hoat tinh lam giam su tang bilirubin va enzym GPT khang su phat trien cua t6 bao u hSc sic t6 trong huyet thanh chugt bi gay tdn thuong chugt va t6 bao ung thu ph6i nguoi nh6 cac gan cip bing carbon tetraclorid [3]. K6t qua hojt chat phellifiiiapyranone A, meshimakobnol nghien cihi ciia Trung tam Sam vi Dugc li?u A, va meshimakobnol B [5, 9]. Nghidn cihi TP.HCM cho thiy cao chiSt c6n vi cao chidt thyc nghifm cho thiy dich chiSt tir nim nuoc tir nim thugng hoing co tic dyng d$p thugng hoang c6 tie dung bao ve tS bio tit goc tu do va lie ch4 qua trinh peroxy hda truoc nhiing ton thuang ADN giy boi g6o ttr mang tS bao, Iim giim su ting him Iugng do oxy [7]. C6ng trinh nghien ciiu cip BO Y MDA trong gan bi gay t6n thuong oxy h6a te theo huong nghien ciru tic dung ho trg bdi cyclophosphamid [2]. TiSp tuc phit triin dieu trj ung thu ciia cac Ioii nim dugc Ii$u theo huong di vio nhom boat chit, chiing tdi trong do CO chi Phellinus cho thiy cao nuoc tiln hinh khio sat host tinh chdng oxy hda in 26 Tap chi Duac Ueu, tap IS, sg 1/2013
vitro cim polysaeeharid v^ cac phan doan chi6t tfit ndm thucmg hoang bang thii nghiem 1,1 - diphenyl - 2 - picrylhydrazyl (DPPH) va thu nghiem malonyl dialdehyd (MDA), va khao s^t tic dung bao ve gan theo huong di6ng oxy hoa "cua polysaeeharid tren thuc nghi?m gay t6n thuong oxy hoa 6 gan chuot nhat trang bang cyclophosphamid, thong qua vi$c xac dinh ham lugng MDA va glutathion (GSH) trong gan.
2. Doi tii'9itg v^ phircng phap nghien cuii 2.1. Doi tuang nghien cuu
Nam thugng hoang dugc cung cap boi Tnmg tam Nghien cuu Linhchi va Nam Dugc li$u. Polysaeeharid tho dugc chiet qua cac giai dogn: chiet nong voi dung moi la nuac a nhiet dp 95'*C (ty le 1:25, kl/tt) trong 6 gio va tua bang c6n 96% (ty le 1:5, kl/tt). Hieu sudt chiSt la 3,09%. Ham lugng ducmg hoa tan la 51%
vaham lugng ducmg khir la 10,92%.
Cac phan doan dugc chuan bi bang each chiet h6i luu Soxhiet bot nguyen lieu nam vcfi methanol theo ty le 1:20 va dich chiet dugc CO giam ap thu dugc cao methanol. Mot phan cao methanol dugc can chinh xac, hoa voi nuac theo ti le 1:10 (kl/tt), chigt qua cac dung moi 'co do phan cue tang dan la diethyl ether, n-butanol va nuoc. Ty le chat ehiet dugc trong cac phEin doan cua cac phan doan n-butanol, phan doan diethyl ether va phan doan nuoc la 49,18%; 41,25% va 9,57%.
2.2. Dong vdt nghien cuu
Chupt nhat trang due, ehung Swiss albino, 5-6 tuan tuoi, trpng lugng trung binh 22 ± 2 g, dugc cung cap boi Vien Vac xin va Sinh phim Y t^ - TP. Nha Trang va dugc dl 6n dinh it nh4t mgt tuin truoc khi thu nghi?m. Chupt dugc nuoi day du bang thuc phim vien, rau xanh va nuac uong.
2.3. Thuoc thi^ nghiem
Endoxan® chiia 534,5 mg cyclophosphamid mon±jdrat Urong Axyc% v5i 500mg cycli^iioqiiamid
khan (Baxter Oncology GmbH, Germany).
Cae thuoe doi chieu: Acid ascorbic (Merck, Germany); Trolox (Calbiochem Ltd. Co.);
Silymarin (Sigma Co.Ltd, USA).
2.4. Phuangphdp nghien cuu 2.4.1. Phuang phap nghien ciiu in vitro:
a. Phuong phap xac dinh kha nang loai b6 g6c tu do (thu nghiem DPPH) [2]
Lay 0,5 ml mau thii a cac nong dp khao sat (10,50,100,500,1000,1500 va 2000 |ag/ml) cho phan ung voi dong lugng dung dich DPPH 0,8 mM pha trong MeOH. H6n hgp sau khi pha dugc de o nhiet dp phong 30 phiit.
Do quang a buoc song ^ = 515 nm. Acid ascorbic dugc sii dung lam chat doi chiSu.
b. Phuang phap xac dinh kha nSng lie ehe peroxy hoa lipid (thii nghiem MDA) [2]
Liy 0,1 ml mlu thii o cac nong dp khao sat (10, 50, 100, 500, 1000, 1500 va 2000 fig/ml) cho phan ling v6i 0,5 ml djch dong the nSo va them dem phosphat vira du 2 ml.
U h6n hgp phan umg a liTC trong 15 phiit va dimg phan iing bang 1 ml acid tricloaeetic 10%. Sau khi ly tam 6 nhiet dp 5°C vai toc dp 10.000 vong trong 10 phiit, lay dich trong cho phan iing vai 1 ml acid thiobarbituric 0,8% trong 15 phiit a nhiet d6 lOO^C. Lam lanh va do quang 6 buoc song X = 532 run.
Trolox, dong phSn ciia vitamin E dugc su dung lam chat doi chieu.
c. Tinh toan ket qua
Cong thiic tinh % hoat tinh chong oxy hoa (HTCO):
HTCO% = [(ODc - ODT) / ODcl x 100 ODc: Mat dp quang cua mau trang (DMSO hay MeOH).
ODT: Mat do quang ciia mau thur.
Cac so lieu ket qua thii nghiem dugc bilu thi bai^ tri so trung binh cua 3 lan do kliac nhau.
ve do thi bieu dien % hoat tinh ch6ng oxy hoa theo nong d6 khao sat cua mau thii nghiem. Tir phuang trinh hoi quy tuydn tinh,
Tap chi Duac liiu, tap 18, so 1/2013 27
ndi suy ra gii trj ndng dg dip tat gdc tu do hay itc chl peroxy hoa lipid IC50.
2.4.2. Phuong phap nghidn cilu in vivo:
a. Gay md hinh tdn thuong gan bing cyclophosphamid [1]
Chugt thi nghiem dugc chia thinh hai nhdm:
- Nhdm binh thudng, ky hieu CY(-):
• Ld chirng: udng nudc cat.
• Ld thur: ulng polysaeeharid thd lieu 100 mg/kg the trong.
• Ld ddi chilu: udng silymarin lieu 100 mg/kg thi trgng.
- Nhdm benh \j, ky bidu CY(+): chugt dugc tiem phiic m^ic lidu duy nhit cyclophosphamid 150 mg/kg the trgng.
Ld chiing: udng nudc cit.
• Ld thii: udng polysaeeharid thd lieu 50 mg/kg vi 100 mg/kg the trgng.
• Ld ddi chilu: udng silymarin lieu 100 mg/kg thi trong.
Thdi gian cho udng hing ngiy trong khoing 8-9 gid sang vi lien tuc trong 8 ngay sau khi tiem cyclophosphamid. Vio ngiy thii 8, mgt gid sau lin cho udng cudi ciing md tich liy gan chudt dem djnli lugng MDA vi GSH.
b. Phuong phap xac djnh him lugng malonyl dialdehyd (MDA) vi glutathion (GSH) trong gan chudt
Tich gan chudt vi nghiin ddng thi trong dung djch KCl 1,15 %. Liy 1-2 ml dich ddng thi, them dung dich dem Tris (pH = 7,4) vira dil 3 ml. i] hon hgp phin irng a ST'C trong 60 phut vi dimg phin ling bing 1 ml acid tricloaeetic 10%.
Xic dinh ham lugng MDA theo phuong phap cua Okawa H. vi cdng su [6]:
Sau khi ly tam liy 2 ml dich trong cho phin img vdi 1 ml acid thiobarbituric 0,8 % d 100°C trong 15 phiit vi do quang d X = 532 nm. Him lugng MDA (nM/g protein) dugc tinh theo phucmg trinh hdi quy tuyln tinh ciia
chit chuan MDA.
Xac dinh him lugng GSH theo phuong phip cia Tietze F. [8]: Sau khi ly tam liy 1 ml dich trong cho phin ting vdi 0,2 ml thuoc thur Eliman la 5,5'-dithiobis-(2-nitroben20ic acid) vi them ddm EDTA phosphat vita *i 3ml. D I 3 phiit cr nhi?t dd phdng vi sau dd tiln hinh do quang cr buoc sdng A, = 412 nm.
Him lugng GSH (nM/g protein) dugc tmh theo phuong trinh hbi quy tuyln tinh cua chit chuin GSH.
c. Dinh gii kit qui
Cac sd li?u dugc bilu thi bing trj sd trung binh: M ± SEM (Standard error of the mean - sai sd chuin cua gii tri trung binh) va xir ly thdng ke dua vio phep kiem One-Way ANOVA va Student - Newman - Keuls test (phin mim Jandel Scientific SigmaStat-98).
Kit qui thir nghidm cd y nghia thong ke vdi dd tin ciy 95% khi P < 0,05 so vdi Id chiing.
3. Ket qua va ban luan J. 1. Kit qud nghien cint in vitro Ho?it tinh lo?i bd gdc t\r do DPPH ciia polysaeeharid vi cac phan do^n chiet tu nam thugng hoing khi so sinh gii tri ICso iJt9C xip theo thii ty: nhu sau: Phin do?n diethyl ether > polysaeeharid > phSn d o ^ n-butanol
> phin d o ^ nudc. Tuy nhien, ho?t tinh niy yeu Idii so sanh vdi gii tri IC50 eiia chat ddi chilu Ii acid ascorbic (Bing 1).
Bang 1. Tong h ^ ICjo ciia cac phiin do^n chi^ tir nam thir^ng ho^ng trong thu nghi$m DPPH
M S U thu- nghidm Polysaeeharid PhSn doEin n-butanol PhSn dogn diethyl ether
PhSn do^in nirdc Acid ascdrbic
ICso(jig/ml) 368,95 772,98 271.32
> 2 0 0 0 46.21
Host tinh chdng peroxy hda lipid, ciia polysaeeharid vi cac phan do?n chilt til.^ipi
28 Tap chiDUfic Uiu, tdp IS, sg 1/2013
thugng hoang khi so sanh gii tri IC50 dugc x ^ theo thii t\r nhu sau: Polysaeeharid >
ph3n doan n-butanol > phan doan diethyl ether, phan dogn nude. Tuy nhien, hoat tinh nky yeu khi so sanh vai gia tri ICjo cua chit doi chi6u la Trolox (Bang 2).
Bing 2. T6ng hgp IC50 ciia cac phSn do?n chilt tir nfim thirong hoing trong thii nghifm MDA
BSng 4. Ket q u i khao sit him lu^ng glutathion (GSH) trong gan
Mlu thir nghi|m Polysaeeharid PhSn do?n n-butanol PhSn do?n diethyl ether Phan do^n nirdc Trolox
ICso ( ^ g / m l ) 1083,98 1796,17
> 2 0 0 0
> 2 0 0 0 860
Di^a vao cac ket qua khao sat hoat tinh ch6ng oxy hoa in vitro ctia polysaeeharid va cdc phSn doan chiet tir nam thugng hoang, chiing toi chon polysaeeharid dS tilp tuc khao sat tac dung chong oxy hoa theo hucmg hko v^ gan trong m6 hinh gay ton thuang gan bang cyclophosphamid tren chugt nhat tring.
3.2. Ket qud nghien cOu in vivo Bing 3. KSt qui khio sit him Iti^ng malonyl
dialdehyd (MDA) trong gan
NhiSm
CV(-)
CY(+) Lo
Chiing Thir Doi chieu Chung Thu
£}di chi^u Li^u u6ng (rag/iig)
100 100
50 100 100
Hilm lu-9'ng MDA (nM/g protein) 76,90 ± 4,82 46,48 ± 3,02' 83,89 ± 5,78 175,58 ± 11,39' 173,36 ±11,78 104,25 ± 9 , 0 1 ' 96,70 ± 9,37"
P< 0,05: khac bi4t co y nghTa thong ke so voi 16 chiing CY(-)
P< 0,05: khac bi^t co y nghTa thdng ke so vai Id ch&ng CY(+) tuang ung
Nh6m
CY(-)
CY(+) L6 Chiing Thil D6i chiSu Chiing Thii
D6I chigu Lilu udng
(mg/kg)
100 100
50 100 100
Hhtn linyns GSH (nM/g protein) II 626,73 ±296,28 11329,20 ±648,83 11739,64 ±550,13 6695,20 ± 3 5 4 , 8 1 ' 6 8 3 I , 1 3 ± 4 5 7 , I 0 9068,51 ± 5 4 5 , 8 1 ' 9863,33 ± 664,68' P < 0,05: khdc bi^t coy nghTa thong ke so vdi lo chung CY(-)
* P <0,05: khdc bi4t co y nghTa thdng ke so v&i 16 chung CY(+) tuang irng
Cyclophosphamid la mpt trong nhfing chat dugc sii dung pho biln trong dilu tri ung thu, chong thai loai trong ciy ghep, dilu trj mpt so benh t\r mien va diing trong cac thi nghiem irc che mien dich. Cyclophosphamid rat nhay vai cac te bao dang phan chia trong do CO cac te bao cua he th6ng mien dich, dong thai lam gia tang qua trinh peroxy hoa lipid trong tl bao gan. Do do, khi tiem cyclophosphamid vao co thi chu6t, gan bi t6n thuang do qua trinh peroxy hoa lipid xay ra manh, sinh ra nhieu MDA-san pham cuoi ciing ciia qua trinh peroxy hoa lipid. Lo chiing tiem cyclophosphamid va u6ng nu6c cat trong 8 ngay co ham lugng MDA trong gan tang co y nghia thong ke so vai 16 chung binh thuang, chiing to cyclophosphamid gay ton thuang peroxy hoa te bao gan dan d6n viec lam tang ham lugng MDA trong gan. Dilu nay do cyclophosphamid dugc bien doi sinh hpc tai gan tro thanh 4- hydroxycyclophosphamid va aldophosphamid CO tinh alkyl hoa, dan den su hinh thanh eac tac nhan gay dpc tl bao nhu acrolein, chloroacetaldehyd [4]. Ngoai ra, nghien ciiu truoc day ciia nhom ciing da chiing minh
Tap chi Duac lieu, tap 18, so 1/2013 29
cyclophosphamid lam giam ham lugng glutathion (GSH), ehat eh6ng oxy hoa noi sinh trong ea thi, e6 y nghia thdng ke so vai 16 chiing sinh ly a ngay thii 8 sau khi tiem cyclophosphamid [1]. Nghien'eiiu nay cung ghi nhan kit qua tuang tu la co su giam ham lugng GSH 6 16 chiing tiem cyclophosphamid so voi 16 chiing sinh ly.
D6c tinh ciia cyclophosphamid Iam suy giam GSH noi sinh trong gan, do do gian tilp lam tang qua trinh peroxy hoa lipid dan den ham lugng MDA tang. Lo thii CY (-) ulng polysaeeharid tho chiet tii nam thugng hoang lilu 100 mg/kg trong 8 ngay co tac dung Iam giam MDA co y nghta th6ng ke so vdi 16 chiing nhung khong anh hudng tren ham lugng GSH trong gan (Bang 3 va Bang 4).
Ham lugng MDA trong gan ciia cac 16 thur Lo thir CY (+) u6ng polysaeeharid tho 6 lilu 50 mg/kg trong 8 ngay chua co su khae bi?t c6 ^ nghia th6ng ke so vai 16 chiing (Bang 3). Ham lugng MDA trong gan ciia cae 16 thit C Y (+) uong polysaeeharid tho 6 lieu 100 mg/kg trong 8 ngay giam c6 y nghTa thong ke so vdi 16 chimg (Bang 3), the hien ro tac dyng lie che s\r gia tang ham lugng MDA trong gan gay ra boi cyclophosphamid.
Tuong tu, ham lugng GSH trong gan cua cac 16 thii CY (+) u6ng polysaeeharid th6 a lilu 50 mg/kg kh6ng thay d6i co y nghia thing ke so v6i 16 chiing CY (+), chiing to polysaeeharid a lieu nay chua thi hien tac dung lam gia tang ham lugng GSH trong gan. Ham lugng GSH trong gan cua 16 thii CY (+) ulng polysaeeharid th6 a lilu 100 mg/kg tang co y nghia thing ke so voi 16 chiing CY (+) (Bang 4), thi hien tae dung eh6ng oxy hoa thong qua viec lam tang ham
lugng GSH trong gan.
Khi so s^nh ham lugng GSH trong gan ciJa 16 ulng polysaeeharid th6 a lilu 100 mg/kg va 16 dli ehilu silymarin a lilu 100 mg/kg sau 8, ngay cho ulng, ghi nhan dugc kit qua IS h ^ lugng MDA va GSH a hai 16 n^y khong khac nhau CO y nghia thing ke (Bang 3 v^ Bang 4).
Nhu vay, tac dung bao ve gan cila polysaeeharid chilt tir nam thugng hoai^
trong thuc nghiem gay tin thuang oxy hoa gan bang cyclophosphamid tuong tu nhu tac dung eiia thulc dli ehilu silymarin.
Kit qua nghien ciiu tnrac day cua Tnmg tam Sam v^ Dugc lieu TP.HCM cho thiy cao chilt c6n va cao chiet nuac tir nam thugng hoang co tdc dung d|lp tat gdc tu do va lie chl qua trinh peroxy hoa mang te b^o, lam giam su tang ham lugng MDA trong gan bj gay ton thuong oxy hoa bdi cyclophosphamid [2], Nghien eiiu nky d3 chiing minh ring polysaeeharid c6 thi la nhom chit quygt djnh tac dung chong oxy hoa theo huong bao ve gan cua nam thugng hoang theo ca ehl lie chl qui trinh peroxy hoa te bao gan va lam tang glutathion npi sinh. Dieu nay eho thay nam thugng ho^g CO tac dung bao ve co the trudc nhflng dpc tinh cua cyclophosphamid tren gan va ggi y hucmg nghien ciiu tiep trSn hS miln djch nham muc dich iing dung nam thugng ho^g trong ho trg dieu tri ung thu.
4. Ket luan
Polysaeeharid th6 chilt tir n4m thugng hoang CO hoat tinh chong oxy hda in vitro vh in vivo theo huang bao v8 gan, phyc hoi sy giam ham lugng chat chong oxy h6a npi sinh glutathion trong gan bi gay tin thuong oxy hoa bang cyclophosphamid.
Tai lifu tham Ithao
1. Ng6 Qu6c Han, Nguyen Thj Thu Hucmg (2011), Nghien cim tdc difng chdng (xcy hoa theo huang bm v^gan cua polysaeeharid chiit tir ndm linh chi vang (Ganoderma colossum). Y hgc TP. Hi Chl Minh, t|p 15, Phy bin cua s6 1, trang 50-55. 2. Nguyen Thj Thu Hucmg, Hfl Dilm Ph6c, U Minh Trigt (2010), Nghien cuu tdc dvng chong oxy hoa ciia ndm Thucmg hodng (Phellinus linteus, Hymenochaetaceae). T?p chf Dugrc li?u, t$p 15(1),
30 Tap chi Duac lieu, tap 18, s^ 1/2013
trang 53-57. 3. Vign Dm»c li§u (2006), Nghien diu phdt trien dupc liiu vd ddng dupc Viet Nam: Nghien aiu xdc
^ink ten khoa hgc, ddu vdn toy hda hpc,vd tdc dtfng sinh hgc cua mdt sd lodi ndm da nien thupc chi Ganoderma vi chi Phellinus. NXB Khoa hgc v i Ky Thuit, H i N0i, 331-343. 4. Abraham P, Sugumar E. (2008), Increased
^utathione levels and activity of PONi (phenyl acetate esterase) in the liver of rats after a single dose qf cyclophosphamide: a defense mechanisml Exp. Toxicol. Pathol., 59(5), 301-306. S. Chang ZQ, Oh BC, Lee SP, Rhee MH, Park SC (2008), Comparative immunomodulating activities of polysaccharides isolated from Phellinus spp. on cell-mediated immunity. Phytother Res., 22(10): 1396-1399. 6. Oltawa H., Oshisi N., Yagi K.
(1979), Assay for lipid peroxides in animal tissues by thiobarbituris acid reaction. Anal. Biochem., 95:351-358.
7., Park BJ, Lim YS, Lee HJ, Eum WS, Park J, Han KH, Choi SY, Lee KS (2009) Anti-oxidative effects of Phellinus linteus and red ginseng extracts on oxidative stress-induced DNA damage, BMB Rep., 42(8):500-505.
8. Tietze F. (1969), Enzymic method for quantitative determination of nanogram amounts of total and acidized glutathione: application to mammalian blood and other tissues. Anal. Biochem., 27, 502-522. 9. Zhu T, Kim SH, ChenCY (2008),^ medicinal mushroom: Phellinus linteus, Curr. Med. Chem., 15(13):1330-1335.
Tgp chiDirffc U$u, tap 18, so 1/2013 (Trang 31 - 38)
D O C T I N H D O I VCtt MOT S 6 TE BAO UNG THlT CUA CAC FLAVONOID PHAN LAP TlT N y VOI
Ddo Trong Tuin, Nguyin Thi Bich Thu, Nguyin Minh Khdi, Phuang Thien Thuang Khoa Hoa phdn tich - Tiiu chudn, Vien Duac lieu
(Nh^n bai n g i y 26 t h i n g 11 nam 2012) Summary
Cytotoxic Activities of Flavonoids Isolated from the Buds of Cleistocalyx operculatus Against some Cancer cell Lines
Fourteen flavonoids 1-14 were isolated from the buds of the plant Cleistocalyx operculatus by repeated column chromatography. Their structures were identified on the basis of physicochemical and spectroscopic analyses. Eleven compounds were tested for their cytotoxic activities against some human cancer cell lines. The most interesting finding is that compound 6 (5-hydroxy-7-methoxy-6,8-dimethylflavanone) exhibited significantly inhibitory effects against Hela cells with an ICjo value of 1.3 tig/ml.
Keywords: Cleistocalyx operculatus, Jlavonoid, cytotoxicity, cancer cell, 5-hyti-ox}>-7-meth(»^6,8-dimethy^avanone.
1. B^t v^n de ciiu ve tac dung sinh hoc cho bilt la, ny v6i C^y v6i e6 ten khoa hgc la Cleistocalyx va eac hoat chat eo tac dung khang khuan operculatus (Roxb.) Merr. et Perry, thupc hg [1], khang virus [4], ch6ng oxy hoa [6], [8], Sim (Myrtaceae) rSX quen thupc voi cac tinh ch6ng benh Alzheimer [7]. Hoat chit chinh ding bang Bic BO [1-3]. Tii lau nhan dan ta ciia ny voi la 2',4'-dihydroxy-6'-methoxy - da diing la vh ny vii hSm liy nuoc ulng, vira 3',5' - dimethylchalcone da dugc chiing minh c6 t6e dyng thanh nhi$t vira co tac dyng kien eo tac dyng chlng ung thu tren in vitro vk in t^, tieu thyrc, diing ngoJli chua myn nhot, gh6 vivo [9-11].
16 [1-3]. Den nay d3 co nhieu nghien ciiu ve Trong mpt nghien ciiu cua chiing toi cho cfiy vii eho biet thanh phin hoa hpc ehinh biet flavonoid la thanh phin hoa hpc chinh ctia la va ny vdl la tinh diu, triterpenoid [3], trong ny voi va chiing co tac dyng chlng vi chu ylu la cac flavonoid [4-8]. NghiSn virus [4]. Dl tim xem c6 them flavonoid nio
Tap chi Duac liiu, tap 18, s^ 1/2013 31
