Nghien CIFU - Ky thuat 2. Kohli Kanchan et al. (2010), "Self-emulsifying drug delivery systems; an approach to enhance oral bioavailability", Drug Discovery Today, 15(21), pp.
958-965.
3 Mahmoud Enas A et al. (2009),
"Preparation and evaluation of self-nanoemulsifying tablets of carvedilol", AAPS Pharmscitech. 10(1), pp.
183-192.
(Ngay nhin bii: 01/06/2014 - Ngay duyet ding: 06/08/2014)
Xac dinh du* lu-ffng hoa chat bao ve thirc vat trong du-tfc lieu kho bang QuEChERS va
r r r f
sac ky long ghep noi khoi pho
TrSn Cao Son', Doan Hanh Dung^
L6 Thi Hong Hao', Thai Nguyin Hung Thu^' ' Vien Kiem nghiem an toan ve sinh thuc pham Quoc gia
^Tnrong Dai hoc Duoc Hd Npi ' E-maiT tnht22@yahoo com
S u m m a r y
A QuEChERS method for determination of pesticide multi-residues in dried medicinal plants by LC- MS/MS was developed and validated. The LOQs were less than 0.01 mg/kg for all pesticides in question.
Most of the pesticides gave spike recoveries from 70 to 110% and the repeatabilities lower than 20%
RSD even at the low concentration (0.01 mg/kg). On application to analyzing 30 dried medicinal plant materials collected at Ha Noi and Nam Dinh province, about 23% of the samples were detected with the pesticide content above 0.01 mg/kg.
Keywords: Determination, QuEChERS method, LC-MS/MS, dry medicinal plants, pesticide multi- residues.
D a t v a n d e
Phuang phap QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) d u g e Anastassiades va Lehotay gidi thieu t u nam 2003 den nay da chiing minh d u g c tinh u u vigt trong viec c h i l t va lam saeh hda c h i t bao ve thuc val (HCBVTV) tren rau qua'^l Hien nay, p h u a n g phap chiet theo QuEChERS k i t hgp v d i ky thu$t sac ky khi k h l i pho hoac sae ky long khoi pho da d u g c c h i p nhan rdng rai tren t h i gid'i '^•^•.
Trong mpt nghien ciiu t r u d c day, chung tdi da l i n g dung p h u a n g ph^p c h i l t QuEChERS va ky thuat sac k^ Idng khoi pho d l ph§n tich dong thdi n h i l u logi HCBVTV trong d u g c lieu t u a i '*'. Phuang phap cho k i t qua tot, cd the xac djnh HCBVTV tai gidi han ton d u toi da (MRL) 0,01mg/kg '^ tren nen m l u d u g e lieu t u a i do
n i n m l u nay cd dp am kha tuong d i n g vdi n i n m l u rau qua. Ham lugng nude cd anh hudng Idn d i n higu s u i t c h i l t ' ' ' nen tren ddi tugng d u g e lieu kho can ed nhu'ng khao sat de thu d u g e hieu s u i t tdt n h i t .
Ddi vdi nen m l u khd, n h i l u tac gia s u dung lugng mau nhd h a n va bo sung them nude d l thu d u g e dd am khoang 80% la do I m ma tai dd hieu s u i t chiet HCBVTV la tot n h i t ^^•''\ Lugng m l u dem phan tich giam di dan den ed t h i tang gidi hgn phat hien cua phuang phap. Han nOa, tren nen m l u d u g e lieu kho thudng cd chiia nhieu tgp c h i t khong mong mudn lam tang anh hudng cua nen m l u den k i t qua.
Trong nghien ciiu nay, chung toi nghien ciiu xay dung va t h i m djnh phuang phap c h i l t QuEChERS k i t hgp vdi LC-MS/MS d l xae djnh HCBVTV trong d u a c lieu khd.
T.4P CHI DlTQC HQC - 8/2014 (SO 460 NAM 54) 13
• Nghien CIFU - Ky thuat
Nguyen lieu va phu^o-ng phap
Doi t u g n g nghien c u u
Cac d u g c thao d u g c khd dupe c h l b i l n sa bp b i n g each phai hoge s l y d u a c l l y tai 3 dja diem sau:
- C h g Ninh Hiep, huyen Gia Lam, Ha Ndi (12 m l u ky higu G01-G12).
- Cae hieu thuoc d pho Lan Gng, quSn Hoan K i l m , Ha Ndi (14 mau ky higu L01-L14)
- Cae gia dinh trdng va eua hang d huyen Hai Hau, tinh Nam Djnh (4 m l u ky higu H01-H02 va H03-H4).
Hoa chat va t h u o c t h u
Cac dung mdi loai dung cho s l e ky g i m methanol, acetonitril va cac hda c h i t acid acetic, natn acetat khan, magie sulphat khan, dinatri citrat sesquihydrat va trinatri citrat dihydrat cua Merck. C h i t h i p phu PSA (primary secondary amine), GCB (graphite carbon black) d u g c cung d p bdi Agilent
Cac c h i t e h u i n gom 25 loai HCBVTV (danh sach nhu trong bang 1) cua Hang Dr.
Ehrenstorfer cd dp tinh k h i l t tren 95%. Viec lua chpn HCBVTV dua tren k i t qua khao sat eac HCBVTV thudng d u g c s i i dung trong ndng nghiep va kha nang phan tieh d u g c b i n g LC-MS/
MS. C h i t ndi e h u i n Iriphenyl phosphat (TPP) eua Hang Sigma Aldrieh. Dung djch c h u i n gdc tiing HCBVTV ed nong dp 1000 pg/mL duge e h u i n bj trong methanol va bao quan trong binh toi d nhigt dp - 4''C. Cac dung djch chuan trung gian Bang 1 : Cic diiu kien phan tieh HCBVTV bir
hon hgp HCBVTV cd nong dp 0,1 pg/mL; 1 pg/
mL va 10 pg/mL d u g c pha trong acetonitnl (c6 ehiia 1 % aeid acetic). Dung djch ehuan chay sac ky d u g c c h u i n bi tren nen m l u t r i n g cd nlng d6 t i i 1 ng/mL d i n 200 ng/mL (tuang duang tr^n m l u la 0,005 mg/kg den 1 mg/kg) v^ nong dp ndi ehuan la 20 ng/mL (tuang d u a n g tren mau la 0,1 mg/kg)
Thiet bj va d u n g c u
Hg t h i n g LC-MS/MS gdm may s l e ky long LC-20AD cua Shimadzu va may khdi pho tii cyc ghep ABI 5500 cua ABSeiex. Cdt sac ky long X-Bridge BEH C I 8 (4,6 x 100 mm; 2,5 pm) va tien cdt cua Waters.
Ap dung d i l u kien LC-MS/MS da duge khSo sat trong nghien eiiu trudei"' vdi pha dOng gdm kenh A (acid acetic 1 % trong nudc) vS B (methanol): ban dau g i i i 2 5 % kenh B sau d6 tang d i n 90% B d 8 phCit, giu' d d i l u kign trong 4 phut va quay ve 25% kenh B d l on djnh opt cho phSn tich cac mau sau. T i e dd ddng g i i i e l djnh 0,7 mL/phuL Tong thdi gian phan tieh la 15 phiit.
The tieh tiem m l u la 10 pL. Doi vdi MS, su dyng n g u i n ion hda ESI(+), the ion hda 5000 V. Moi HCBVTV chpn 1 ion phan t i i va hai manh ion san pham, mdt dung d l dinh l u g n g va mpt dung de k h i n g dinh (bang 1).
Cac dpng eu, t h i l t bj thdng thudng kh^c cua phdng thi nghiem bao g i m can ph§n tich (XT22A, Precise), may xay n g h i i n m l u (HR1843, Phillips), may ly t§m (Z383K, Hermle), may lac xoay (IKA), micro pipet va eae loai dng ly t&m (50 m L v ^ 12 mL).
? LC-MS/MS HCBVTV
Acetochlor Aldicarb Atrazine Azoxystrobin Abameetin Aeetamiprid Carbaryi Carbofuran Carbendazim Carboxin Dichlorvos Dimethoat Edifenphos Emamectin Fenobuearb
Ion phan tu> (m/z) 270,0 213,0 216,0 404,0 890,5 223,0 202,0 222,0 192,0 236,0 221,0 230,0 311,0 886,5 208,0
Ion dinh luvng' (m/z) 224 (13) 116(15) 96(31) 372(19) 305(31) 126(25) 145(13) 165(15) 160 (23) 143(19) 109(23) 199(13) 283(17) 158(39) 152(11)
Ion dinh tinh * (m/z) 148(25)
89(15) 104(37) 344(31) 567,5(17)
56(19) 127(37) 123(29) 132(39) 87 (29) 127 (18) 125(27) 109 (35) 302 (35) 95(19)
Thm gian lu>u (pliOt) 10,8 8,03 9,61 9,83 13,9 6,90 9,10 8,74 5,35 9,08 8,71 7,03 11,0 11.0 10,1
TAP CHi DirpC HQC - 8/2014 (SO 460 NAM 54)
• Nghien cii'u - Ky thuat
Imidachiorprid Indoxacarb isoprocarb Methiocarb Ivlethomyi Profenophos Propoxure Terbuconazoi Thiamethoxam Tnchiorfon TPP (IS)
256,0 528,0 194,0 226,0 163,0 373,0 210,0 308,0 292,0 257,0 327,0
209(21) 249(21) 95(19) 169(11) 88(13) 303(23) 111 (19) 125(39) 211 (15) 109(23) 77(61)
175(27) 293 (17) 137(11) 121(23) 106(13) 345 (17) 93(31) 151 (31) 181 (29) 221 (15)
6,32 11,3 9,55 10,3 4,89 11,9 8,67 11,1 5,29 6,97 11,1 'Gia tri trong ngoac la nang luang ban pha (eV)
K§t qua va banluan Phu'O'ng phap x u ly mau Bo sung nwoc vao mau
Quy trinh e h i l t QuEChERS cho higu s u i t c h i l t tdt n h i t vdi n i n m l u rau qua ed dp I m khoang 80% t^^. Nen mau d u g e lidu khd cd dp I m thap (<5%) do dd e i n bo sung n u d c trudc khi chiet. D l dam bao dp am cua mau trudc khi c h i l t khoang 80%, n u d c d u g e them vdi ty le m l u : n u d c la 1:5 (w/w) trudc khi c h i l t . Theo mot nghien c i i u t r u d c day tren n i n m l u thge pham chiic nang cd thanh phan thao d u g e '^', sau khi them n u d e m l u d u g c chiet ngay de tranh s u thuy phan cua mot so HCBVTV.
Khao sat each on dinh pH djch ehiet Phuang phap QuEChERS cd 3 phien ban ung dung tren rau qua, do la phuang phap ban dau khdng s i i dung dem theo Anastassiades '•'', phuang phap dung dem acetat theo AOAC 2007.01 '^' va phuang phap dung dgm theo EN 15662 [3]. Do eae logi d u g c lieu cd pH khac nhau ed t h i anh hudng d i n hieu s u i t c h i l t nen chung tdi t i l n hanh khao sat anh hudng pH djch c h i l t d i n dp thu hdi eua cac HCBVTV.
Hai logi d u g c lieu la day thia eanh (TC) cd pH trung tinh va la giang (LG) cd pH acid d u g c them ehuan HCBVTV de thu d u g c n l n g dp tuang d u a n g 0,1 mg/kg. XLF iy m l u theo 3 quy trinh, lap lai mdi qui trinh 3 lan. pH eua eac dieh c h i l t thu d u a c nhu d bang 2.
Bang 2: pH cOa djeh ehiit thu duuc theo 3 phuung phap xCrly mau
Phuong phap Dung moi chiet pH dich chiet
TC LG Kh6ng d#m '^ 6 g MgSO^ khan; 1,5 g NaCl
P$m acetat '^ 6 g MgSO^ khan; 1,5 g natri acetat Acetonitnl 1% acid acetic 6 g MgSO^,
1,5 g NaCl;
1,5 g tnnatri citrat.2H30;
0,75 g dinatri citrat .1,5H,0 T h i n g ke so lugng HCBVTV cd dp thu hoi thudc cae m i i c (tren 80%, 70-80% va d u d i 70%)
theo 3 p h u a n g phap XLF ly m l u vdi 2 n i n mau d u g c tdm t i t trong hinh 1.
Hinh 1 : Sd HCBVTV co do thu hdi thudc eae mue khi xCrly mau theo 3 quy trinh tren 2 nin mau
TAP CHI DlTQC HQC - 8/2014 (SO 460 NAM 54)
Nghien CLFU - Ky thuat
K i t qua cho thay, tren n i n m l u day thia canh, pH cua djch chiet kha on djnh doi vdi ca 3 phuang phap; phuong phap khdng s i i dung dem eho dp thu hoi tot nhat. Tuy nhien, tren n i n m l u la giang (pH aeid), phuong phap khdng dung dem cho higu qua r i t t h i p , 20/25 HCBVTV phan tfch cd dp thu hdi d u d i 70%. Phuang phap dung dgm citrat cd dp thu hoi tot han nhung chua dap ling d u g c yeu c l u (14/25 HCBVTV cd dp thu hdi d u d i 70%). Phuang phap dung dem acetat cho pH on dmh n h i t va dp thu hdi cua cac HCBVTV deu dap ling d u g c yeu c l u . Mat khac do nen m l u d u g c lieu da dang v l tinh acid base, do dd vigc SLF dung dem la c i n thilt.
Khao sat muoi chiet
De khao sat kha nang lam giam anh hudng n i n cua NaCl, chung tdi bo sung NaCl vao qua trinh c h i l t
T i l n hanh them NaCl vao muoi chiet vdi cac khoi lugng nhu sau: 0 g; 0,5 g; 1,0 g; 1,5 g va 2,0 g. Them chuan de dat n l n g dp tren m l u la 0,1 mg/kg. Cac k i t qua v l do thu hdi d u g c tdm t i t d hinh 2.
• >80K • 70-80% •
i.lLli.l.
OSfifJaa LOgNaCI ISgNaCI 2 0gHinh 2: So HCBVTV cd do thu hoi thude cac muc khi cd s u dung them cac luung NaCl khic nhau trong qua trinh x u ly miu
Ngoai ra, khi tang luong NaCl thi pH eua dich chilt acetonitril giam dan ti> 5,88 (0 g) d i n 5,63 (1,5 g) va 5,50 (2 g); mau sac dich chiet cung nhat d i n cho t h i y NaCl ed the cd vai trd quan trpng trong viec taeh giiia hai pha n u d c va acetonitril.
Nhu vay, viec s i i dung NaCl trong muoi c h i l t cd anh hudng d i n dd thu hdi cua phuang phap.
Lugng NaCl t i t n h i t la t t i miie 1,5 g. Do vgy khoi lugng NaCl them vao muoi c h i l t duge lua chpn la 1,5 g eho 15 mL dich c h i l t acetonitril.
Ddnh gia vai tro cda chat noi chuan Danh gia anh h u d n g cua n i n m l u den tin hieu cae HCBVTV b i n g each so sanh he so gdc cua hai dudng chuan, mdt d u g c pha tren acetonitril ehiia 1 % aeid acetic va mot d u g c pha tren djch e h i l t mau t r i n g . Anh hud'ng nen c i n phai thip han 20%. Anh hudng cua n i n cd t h i dugc c^i thien khi s i i dung p h u a n g phap chuan nOi.
Bang 3: So sinh muv do anh huang nin khi khdng s u dung va cd su" dung ngi chuin
Mire do anh huvmg tren 20%
10^20%
5-*10%
du'O'i 5%
cua nen So HCBVTV dat Khong IS Co IS
14 2 8 7 2 4 1 12 K i t qua d bang 3 cho t h i y , neu khdng SCF dung npi chuan da so cac HCBVTV cd anh hudng nen tren 20%. Khi djnh l u g n g theo phuang phap ehuan ndi (sii dung TTP), anh hudng n i n giam ro ret, 23/25 hgp e h i t ed anh hudng nen du'di 20%, trong dd khoang mdt nua so HCBVTV co anh hudng nen d u d i 5%. Do dd. vigc sii dung ndi ehuan rat can t h i l t de giam bdt cac sai so do n i n m l u .
Tham djnti p h u c n g phap
Vdi cae dieu kien x u ly mau va phan tich da xac djnh p h u a n g phap d u g c t i l n hanh thim djnh cac npi dung va thu d u g c cac k i t qua nhu sau:
Gioi han phat hien va gidi han djnh Iwang De danh gia LOD va LOQ cCia phuang phap, chung tdi tien hanh phan tieh eae m l u them c h u i n tgi cac ndng dd 0,005 mg/kg va 0,01 mg/
kg (tinh tren mau). Xdc djnh LOD va LOQ dp'a vao ty le tin hieu tren nhieu. K i t qua cho thiy, tat ea cac HCBVTV deu cd the dinh lugng dugc tai ndng dp 0,01 mg/kg ma khdng can them budc lam giau mau.
Khoang tuyin tinh
Phan tich day c h u i n cd ndng dp t u 0,005 den 1 mg/kg (tinh tren m l u ) eho thay trong khoang nong do nay tin higu cua cac HCBVTV ty le tuyen tinh vdi ndng dp vdi r > 0,99. D u d n g c h u i n dugc kiem tra nguge de dam bao dO lech khdng qua 2 0 % so vdi gia tn thuc.
16 TAP CHi DlTQC HOC - 8/2014 (SO 460 NAM 54)
Nghien ciru - Ky thuat
D p lip lai va do thu hoi
Danh gia dp lap lai va dp thu hoi thdng qua phan tich cae m l u day thia eanh (TC), trinh nCF hoang eung (TNHC), cd ngpt (CN), ma d l (MD), la giang (LG) them e h u i n d 3 miie ndng dp 0,01 mg/kg; 0,1 mg/kg va 1 mg/kg. Ky hieu eae m l u theo dgng TCO.OI la mau day thia eanh d m i i c ndng dp 0,01 mg/kg. So lugng HCBVTV ed he so bien sai (CV%) va dp thu hoi (R%) d eae miic d u g e tdm tat d bang 4 va bang 5.
Bang 4: Kit qua xic dinh do Igp lai cua phuung phip trin eie nin miu khie nhau
IVlau va n6ng dd T C I TC0,1 TC0,01 TNHC0,01 CN0,1 IWIB0,1 LG0,1
Bang 5:
phiKrng ph^p Mau va nong do T C I TC0,1 TC 0,01 TNHC0,01 CN0,1 MB 0,1 LG0,1
So HCBVTV CO he s6 CV(%) 0-^6
20 19 11 16 22 21 20
6 - . W 10^15 5 5 10 5 3 3 5
0 1 3 3 0 1 0
i bien sai 15-20
0 0 1 1 0 0 0 KSt qua xac dinh dQ thu hoi cua ' tren cac nen miu khac nhau
So HCBVTV CO d^ thu hoi R (%)
<70 70-.8(3 80^110 110-120 >120 2
2 3 3 1 2 0
11 8 3 7 6 6 12
12 14 18 13 17 16 12
0 0 1 0 1 0 1 1 1 0 1 0 1 0 Cac k i t qua eho t h i y , da s l eae HCBVTV cd dp thu hoi trong khoang tir 70-110%. Tren mdt so n i n m l u dgc biet, tai nong dp thap 0,01 mg/
kg cd dp thu hoi n i m ngoai khoang tren nhu profenofos (TNCOI: 138%); carbaryi (TN0,01:
65%); carbendazim (TN0,01: 60%); carboxin (TC0,01: 60%). Cae gia trj dp thu hoi t h i p hoac cao d u g e loai t r i i khi s i i dung npi chuan.
D p lap lai d u g c tfnh tren m l u trang them c h u i n va mau thuc (co HCBVTV) deu r i t tdt vdi gia tri he so b i l n sai d u d i 10% doi vdi da so cac trudng hgp (94%). Khdng ed mau nao ed he sd b i l n thign v u a t qua 2 0 % dap i i n g d u g c cac yeu c l u v l phan tieh d u l u g n g .
D u l u g n g HCBVTV t r o n g d u g c lieu k h o Phuang phap d u g c ung dung d l phan tich HCBVTV trong 30 m l u d u g c lieu khd. Cac k i t qua d u g e trinh bay trong bang 6.
Bang 6: Kit qua phan tich HCBVTV trong duuc lieu khd
Miu Dugc lieu
G01 Rau ngo G02 Chodengot G03 Ich mau 304 Nhan tran G05 Chd de rang cua G06 Kim tien thao -^y Trinh nu hoang
cung GOB Bo cong anh G09 Coi xay GIO Ngai ciiu G i l Hoasa G12 Tang kisinh LOI Don do L02 Congot
L03 M a d I
L04 Rau ma LOS Hoa nhai L06 Kho sam L07 Coxuac LOS Xau ho L09 Bac ha L10 Nho noi Ll 1 Che vang L12 Che day L13 Sai ho nam , J , Trinh nu L14 . .
hoang cung
HCBVTV phat hien duw (nong do, mg/kg)
Imidacloprid (0,25) /kzoxytrobm (0,15), Carbofuran (0,015).
Fenobuearb (0,010) Atrazin (0,020)
Tercobunazol (0,25), Carbendazim (12.1), Avermectin (0,30), Azoxytrobin (1,1) Aeetamiprid (0,045) Imidacloprid (0,075)
Noi lay mau
Hiep, Gia Lam,
Pho Lan Ong, Kiem,
HOI Day thia canh H02 Oinh lang HOS Kinhgiai
H04 Diep ha chau Imidacloprid (0,051) - Nam
N h u vay, cd 7 mau (khoang 23%) trong so 30 mau d u g e lieu d u g c phan tich cd chiia HCBVTV.
Ca 7 mau nay d i u d u g c l l y d chg hay ciia hang ban d u g c lieu. Trong cac HCBVTV phat hign d u g c , t i n s u i t x u i t hien Idn n h i t la cac HCBVTV nhdm neonieotinoid vdi 4/7 mau.
T^P CHI DUQC HQC - 8/2014 (SO 460 NAM 54) 17
Nghien CCPU - Ky thuat
Ket luan
Da khao sat xay dgng va tham dmh phuang phap QuEChERS phdi hgp ky thuat LC-MS/IVIS de phan tich da d u lugng HCBVTV trong mdt s l loai dugc lieu khd. Phuong phap cd dp nhgy tdt vdi LOQ dudi 0,01 mg/kg, da s l cac c h i t ed dp thu hdi t i i 70-110% va dp lap lai t i t (CV% < 20%) ngay d ham lugng t h i p (0,01 mg/kg). Da danh gia d u lugng eac HCBVTV nay trong 30 logi d u a c lieu khd l l y tai Ha Ndi va Nam Djnh, khoang 23%
m l u ed HCBVTV vdi n l n g dp tren 0,01 mg/kg.
Tai lieu tham khao 1. Anastassiades M., Lehotay S. J., Stajnbaher D., and Schenck F. J. (2003), "Fast and easy multiresidue method employing acetonitnle extraction/
partitioning and dispersive solid-phase extraction for the determination of pesticide residues in produce" J.
AOAC/nf., 86(2), 412-431.
2. AOAC International (2010), "AOAC Official Method 2007.01 Pesticide Residues m Foods by Acetonitrile Extraction and Partitioning with Magnesium Sulfate," AOAC Official Method.
3. EN 15662 (2009), "EN 15662:2009 Foods Of Plant Origin - Determination Of Pesticide Residues
Using GC-MS and/or LC-MS/MS) - Quechers Method", European Standard.
4. Tran Cao San, Le Thj Hong H^o, Ho^ng Thj Thuy Hang, Thai Nguyin Hung Thu (2013), "Xac dinh da du lupng hoa chat b i o ve thuc vat trong dupe lieu tuoi bang phuang phap QuEChERS va s i c ky long khoi pho", Tap chi Dugc hQC AZ^ (10), 20-25.
5. European Council (2005), Regulation on maximum residue levels of pesticides in or on food and feed of plant origin, EC 396/2005.
6. Lozano A., Rajski L., Belmonte-Valles N., Ucles A., Ucles S., Mezcua M. & Fernandez-Alba A.R. (2012),
"Pesticide analysis in teas and chamomile by liquid chromatography and gas chromatography tandem mass spectrometry using a modified QuEChERS method - Validation and pilot survey in real samples", J. Chromatog.A.. 1268, 109-122.
7 Shoeibi S., Amirahmadi M., Rastegar H., Khosokhavar R. & Khanghah A. M. (2013), "An applicable strategy for improvement recovery in simultaneous analysis of 20 pesticides residue in tea", J. Food SCI., 78 (5), 792-796.
8. Tran Cao Son, Le Thi Hdng Hao. Nguyen Van Hiing, Tran Thi Thuy, Thai Nguyen Hung Thu (2013),
"Xac dinh da d u lugng HCBVTV trong thgc pham chue nang co thanh phan thao dupe bing sic ky long hai lan khoi pho". Tap chi Phan tich Hoa, Ly va Sinti hoc. ^Q (3), 69-77.
(Ngiy nhan bai: 26/04/2014 - Ngay duyet dang: 06/08/2014)
Nghien ciru dieu kien dong kho te bao nam men Saccharomyces boulardii
Nguyin Tii Anh'*, Ta Minh Hai^
'Klioa Duoc - Dgi lioc YDuac TP. H6 ChiMinii,
^Truang Dgi ligc Kiioa iioctu nhien TP. Ho Clii Minii
* E-mgii- [email protected]
Summary
As it is the freeze-drying process for presen/ing living microorganisms in pharmaceutical products for treatment and prevention of intestinal bacterial disorders, such as bacteria Lactobacillus acidophilus, Lactobacillus casei, Bifidobactetium bifidum, ...and the yeast Saccharomyces boulardii, itself, to be the main cause of a dramatical reduction in microrganism population, especially for the yeast cells of larger size than bacteria, 34 freeze-drying media to improve survival Saccharomyces boulardii were investigated. The optimal medium capable of maintaining the 40.2% of the population of yeast cells was composed of: 25 g milk, 10 g of lactose, 2 g Alginate Na * and 4 g CaCI, in 100 mi water. The concentration of milk, sugar and the ratio of alginate Na+/CaCI, remarkably affected the survival of S.
boulardii during freeze-drying. With these chosen components were readily available, the proposed
T^P CHi DirpC HQC - 8/2014 (SO 460 NAM 54)
