Tgp chi Khoa hgc TrudngDgi hgc Cdn Tha Phdn A: Khoa hgc Tv nhien, Cdng nghi vd Mdi Irudng: 35 (2014): 1-8
Tap chl Khoa hgc Tru'dng Dai hpc Can Thtf website: sj.ctu.edu.vn
SAN XUAT CHAT BEO TlT VI TAO CHLORELLA SP.
STJ" DUNG TONG HOP DIESEL SINH HOC
Hd Quoc Phong', Trin Dong Au^, Trin Suang Ngoc^, Huynh Thi Ngpc Hien^, Huynh Lien Huong' va Nguyin Trong Tuan"
' Khoa Cong ngh4, Trucmg Dgi hgc Cdn Tha
^ Hgc viin cao hgc Cong nghi hoa hgc, Trudng Dgi hgc Bdch Khoa Thdnh pho Ho Chi Minh
^ Khoa Thiiy sdn, Trudng Dgi hgc Cdn Tha
* Khoa Khoa hgc Tv nhiin, Truong Dgi hgc Cdn Tho Thong tin chung:
Ngay nhgn: 01/07/2014 Ngay chdp nhdn: 29/12/2014 TUle:
Lipid production for biodiesel synthesis from Chlorella sp.
Tir khda:
Chdt beo, Chlorella sp., diesel sinh hgc, vi Ido Keywords:
Lipid, Chlorella sp, biodiesel, algae
ABSTRACT
Searching for potential feedstock for biodiesel synthesis is important today and microalgae Chlorella sp. can be used to produce biodiesel due to its high capacity of lipid accumulation. Therefore, this study was conducted lo investigate the effects of culture conditions on the growth and lipid accumulation of Chlorella sp. such as light intensity, time, temperature and salinity. The results showed that the obtained concentration oJ microalgae was 0.306 g/L and the accumulated lipid was up to 35.86%
when it was cultured under the conditions of 1342 lux, 25X!, salinity of 0%o and incubation time of 8 days. In addition, the fatty acid composition of Chlorella sp. was mainly C16 - CIS, which are suitable for biodiesel synthesis.
Viic lim kiim nguon ngi^in lieu tiim ndng cho qud trinh long hgp biodiesel Id rdt cdn thiet hiin nay vd vi tao Chlorella sp. co thi sir dung di long hgp biodiesel do co khd ndng lich lOy nhiiu chdt bio. Do do, nghiin ciru ndy dugc tiin hdnh nhdm khdo sdt cdc dieu kiin dnh huong din sif sinh truong vd tich IQy chdt bio cua vi tao Chlorella sp. nhu cuong dg sdng, thdi gian, nhiit dg vd dg man cua nude. Kit qud cho thdy rdng vi tao Chlorella sp. co the dgt dugc nong dg sinh khoi 0,306 g/L vol chdt bio tich liiy lin din 35,86% khi dugc nuoi cdy a diiu kiin cuong dg chieu sdng 1342 lux, nhiet dg 25°C, dg mdn cua nude 0%o vd thdi gian nuoi cdy Id 8 ngdy. Thim vdo do, thdnh phdn acid beo cua vi tao Chlorella sp. chu yiu Id CI6 - CIS. ddy Id nguyen lieu phu hgp cho long hgp biodiesel.
1 GIOITHIfU
Sy phit triln nhanh chdng ciia cdc nginh cdng nghiep trin thi gidi hien nay dang lim can kilt din ngudn nguyin lieu boa thach la dau md. Ddy li ngudn tai nguyen khdng thi phyc hdi. Ciing vdi dd la sy d nliiem mdi Uudng do vile dot nhiin lipu cd ngudn gde tir diu md giy ra, trong dd cd nhiing khi
thai dOc hgi vd rat khd xii ly nhu COx, SOx. Vi vgy, vile nghien ciiu de tim ra ngudn nguyen lieu ed thi thay thi ddu md li mpt vin di rit dupe chii trpng uin thi gidi ciing nhu d Viet Nam. Biodiesel li nhiin lieu thay the tiim nang eho diesel hda thgch vi nd cd tbi phan hiiy smh hpc, khdng ddc, cd thi tdi chi, thin thien vdi mdi trudng v i cd thi phoi
T{^ chi Khoa hgc Trudng Dgi hgc Cdn Tha Phdn A: Khoa hgc Tu nhiin, Cdng nghi vd Mdi Irudng: 35 (2014): 1-8 trpn voi diesel hda thgch vdi bit 1^ ti le ndo (Ju,
Huynh et al., 2013). Tuy nhien, gia thinh sdn xudt biodiesel cdn rat cao chua ifal cgnh tranh vdi diesel hda thach do hai ylu td quan trpng la ngudn nguyen lieu va cdng i ^ l sin xuiL Ngudn n ^ y l n lieu sdn joiit biodiesel thuong mai chu ylu l i ngudn chdt beo tir diu diu ninh, diu cp, dau hgt hudng duong thuong cd ^ i rit cao va chiim den 50-70% gja thanh sdn phdm (Mata, Martins et al, 2010). Ngoai ra, vile lam dyng cac ngudn ngi^ln lieu dd cd thi anh hudi^ din an ninh luong thyc.
Do do, viec tim ngudn nguyin Iilu cbit beo sin xuat biodiesel Id rdt can thilL Qua nhilu khio sit dinh gii cho tiiay vi tao la vi sinh vit tilm ning d&
sin xuit chat beo nguyen heu do chiing cd kha ning quang hpp mgnh, phat triln nhanh kl ca uong nhiing diiu kiln khic nghilt mi cic logi cay trong khdng thi chiu dupe. Chung cd thi tgn dyng nitrogen va phospho trong nude thdi eua ndng n^ipp, cdng nghiep va ca nude thai dd thi, cd kha ning hip thy CO; sinh ra do qui trinb ddt nbiln lieu (Zhou, Ge et al, 2013). Die bilt li khi ning cho thu hoach rdt nhanh chi tir 7-10 ngay (Mata, Martinse/^a/., 2010) va lupng chat beo tich luy khi cao. Vi the, nghiin ciiu nay dupe thyc biln nhim tim bilu inh hudng cua cac dilu kiln nudi ciy din sy phat triln v i kha nang tich luy chdt beo cua vi tao Chlorella sp. tir dd cd the tim ra dupe dilu kiln nudi cay phii hpp nbim thu dupe lupng chit beo nhilu nhit phuc vy cho viec sdn xudt biodiesel.
2 PHU*aNG TI?N VA PHU'ONG PHAP THVC NGHIDM
2.1 Vgt li|u vi hda chit
Ngudn vi tie dupe su dyng Id Chlorella sp.
dirpc cung cap boi phdng thi n^bipm vi tio - Khoa ThOy san - Trudng Dai bpc Cin Tho. Mdi tnrdng nudi cdy vi tao dupe chuan hi dya Uin mdi trudng
Walne bao gdm cdc thdnh phan: 1,3 g/L FeCl3.6H20, 0,36 g/L MnCl2.4H20, 33,6 g/L H3PO4, 20 g/L NaH2P04.2H20, 100 g/L NaNOj, 45 g/L EDTA va Dung dich B (1 ml/L) gdm cac tiianh phin: 1,05 gfl. ZnCb, 0,05 g/L (NH4)6.M07024.4H20, I g/L CUSO4.5H2O, 10 mL/L HCI ddm die, 1 g/L C0CI2.6H2O. Di khio sat thanh phdn chdt beo can cac dung mdi diing di trich ly va phdn tich sac ky khi (GC), chit chuin methyl ester cua cdc acid beo dupe mua tu Sigma- Aldrich (My). Cac dung cy phyc vy phari ti'ch Uong qua Uinh nudi cay bao gdm Quang kl LTluUon LX-i03, nhiet kl diln tii cim tay Hanna, kinb hiin vi OLYMPUS CX21 vdi budng dim Haemocytomete Burker Marienfeld, may quang phd UV-Vis UVl/Thermo Elecfron, tiiiit hi chiit soxhlet
2.2 Nuoi cay vi tao
Ngudn nude miy nudi cay vi tio dupe tien hanh khu triing bang javel dam die vdi ndng dp 1 niL/L Uong 30 phiit. Sau dd javel dupe khir bing NaiSiOa 30% vdi chat chi thj KI cho din khi khdng cdn javel. Dung dieb Walne dupe eho vdo nude vdi ty ll 2 - 3 mL/L de tgo tharUi mdi trudng nudi cay va tao gidng dupe eho vio bl nudi vdi \y le 1: 10 (ty ll thi tich). Sii dyng phuong p h ^ khdo sit ludn philn timg biln de khao sdt sy dnh hudng ciia cdc dieu kien nudi ciy den khi ning tich luy chit bio ciia vi tio Chlorella sp. nhu cudng dp chilu sang, nhiet dp, thdi gian vd dp mgn ciia nude dung dl nudi cay. Sinh khdi vi tio d radi thi nghilra dupe thu hoach bang cich ly tam vd say khd d nhiit dd 50°C Uong 8 gid rdi dupe tien hdnh trich ly danh gia ham lupng chit bio. Tii do tim ra dupe dilu kiln t6i uu dl nudi ciy vi tao Chlorella sp. nhim thu dupe nhilu-'clidt;bed~vd" thanh- phan phii hpp cbo qui Uinh tong bpp biodiesel.
Tgp chi KhoaitQC Tmcmg Dgi hoc Cdn Tha Phdn A: Khoa hoc Tv nhien. Cong nghf va Moi m^g: 35 C20J4): ISf
B I nuoi chua moi tniong..
Hinb 1: So do quy trinh 2.3 Phuong phip phin tich dinh gia 2.3.1 Xdc dfnh nong do sinh khoi vi tao Ndng dd sinh khdi vi tao Chlorella sp. Uong dung dich dupe xdc djnh bdng may quang phd UV- Vis UVl/Thermo ElecUon d budc sdng 680 nm (Saechetti, Maietti et al, 2005; Tang, Chen et al, 2012; Zhou, Ge et al, 2013). Ndng dp sinh kbii dupe tinh bang cich so sanh vdi dudng chuin dupe xiy dyng tir 5 m§u dupe xic dinh bang budng dim Haemocytomete Burker Marienfejd Uen kinh liien vi OLYMPUS CX21. 5 rndflTsmb^khdi sdudddirpc siy khd d 50''C di xac dinh khii lupng vi tio khd trin mOt don vi thi tich.
2.3.2 Ddnh gid hdm lugng chdt beo Sinh khdi vi tio dupe thu hogch bdng phuong phap ly tim sau dd dupe siy d nhiet dd thip -50
"C. Chit beo dupe trich ly khdi sinh khoi khd bing phuong phap chiit soxhlet vdi h§ dung moi Chloroform-Methanol (2:1, tj 11 thi tich) (Zhou, Ge et al, 2013). Dieb Uich dupe Uich long long vdi dung mdi hexane di loai bd dilp luc to, chdt beo tich liiy (%) dupe xdc dinh dya Uin ti ll giua khoi lupng chat beo dupe trich ly vd khoi lupng sinh khoi khd da su dyng. Vi the, lupng chat beo thu dupe d mdi tiii nghiem dupe tinh nhu sau:
nudi cay vi tao Chlorella sp
Lupng chit bio (g/L) = Chit beo tich luy (%) x Ndng dp sinh khii khd (g/L).
2.3.3 Phdn tich thdnhphdn chdt bio Qk phdn tich dupe thdnh phan acid beo thi chat bio phdi dupe xd ly di chuyin cie acid bio tu do ciing nhu cac Ui-, di- vi monoglyceride thdnh dang methyl ester eua cdc acid beo: 5 g chit beo dupe xii ly bing 4 mL methanol ed chiia H2SO4 3,3%
(g/l 00 mL), khuiy tir d nhiet dp 65°C Uong 120 - 180 phiit. Sau dd cho thim 2 mL methanol cd chira KOH 10% (g/100 mL) rdi tiip ti^c khuiy ttr d 65 X Uong 60 phut. Hon hpp sau xur 1^ dupe rira vdi nude khir ion dl logi bd xuc tic cdn du, sau do tiln hinh Uich ly Idng Idng bang hexane de thu sin phim (Chen, Liu et ai, 2012; Tsigie, Huynh etal, 2012). Cac mau phdn tich dupe pha loing bang hexane vdi hdm lupng 20 mg/mL. Dilu ki§n phin tich: may sic k^ khi GC-2010 plus (Shimadzu, Nh^t Bdn), Cot ZB5-HT (15 m x 0,32 mm), diu dd ion hda ngpn lu:a (FID) (Chen, Liu et al, 2012) vdi chuong trinh nhiet dupe cai dit nhiet dO budng tilm v i ddu dd la 370°C, nhiet dO cpt bit diu d 80°C tang lln 365''C vdi tie dp ISX/pbiit va giii Uong 10 phiit, tdng thdi gian phdn tfch li 29 phut.(Tsigie, Huynh et al, 2012).
Tgp chi Khoa hgc Trudng Dgi hgc Cdn Tha Phdn A: Khoa hgc Tv nhiin. Cdng nghi vd Mdi trudng: 35 (2014): 1-8 3 KET QUA VA THAO LUAN
3.1 Anh hudng cua thdi gian va cudng do chilu sing din s^ phit trien va tich luy chat bio cua vi tao Chlorella sp.
Vi tao Chlorella sp. dupe nudi cay d 4 dilu kiln chieu sdng trung binh khic nhau la 1342 lux, 730 lux, 333 lux va 9840 lux, d nhiet dp 25°C, nude c6 dp man 0%o (hay nude ngpt), frong khodng thdi gian tir 1-8 ngay. Kit qui cho thiy rir^ cudng dp chilu sang dnh hudng manh me den sy sinh trudng vi phat trien ciia vi tio Chlorella sp.. CJ cuong dp chilu sdng qua cao (9840 lux) hay qud thip (333 lux) khdng phdi la dilu kiln thudn lpi di vi tio Chlorella sp. phdt Uien. Vi tio Chlorella sp. phit Uien nhanh d cudng dp chilu sang 730 lux v i tdi
uu d 1342 lux (Hinh 2). Ct cuong dp chieu sang 9840 lux xdy ra hiln tupng lie chi quang hpc (photomhibition) (Richmond 2004; Scott, Davey et al, 2010; Cheusilp and Torpee, 2012) lam inh hudng xdu din sy phit trien cua vi tdo va cudng dp chilu sang d 333 lux khdng dii cung cap cho qua Uinh quang hpp ciia vi tao. Do dd, cudng dp chieu sang phii dira bdo eung cap dii cho vi tio quang hpp nhung khong vupt qua miic dp ire chl quang hpc ciia vi tio. Kit qua thi nghiem ciing cho thay rang ndng dd vi tao tang nhanh theo thdi gian v i cao nhat vio ngay thii 8. Neu tiep tuc nudi ciy thi tdo se khdng tang mat dp md bit dau suy tin do cd hien tuong ling xuong day. Rieng d cudng dp chieu sang 333 lux thi ndng dp sinh khdi tang rdt cham vd ed diu bilu hi giam d ngay thii 6.
khoi(g/L)
J3 a
i
UD
a Z.
0.30 0.25 0.20 0.15 • 0.10 0.05
- ^ 1 3 4 2 lux - ^ 7 3 0 lux - ^ 3 3 3 lux -^—9840 lux
I I I I
0 2 4 6 8 1 HiM gian (ngay)
0
Hinh 2: Bh thj bilu dien anh budng ciia thdi gian va ctrdng dp chilu sang din su* phat trieu cua vi tio Chlorella sp.
Sau 8 ngiy nudi ciy vi tio Chlorella sp. dupe thu hoach v i dinh ^ d kha niiig tich luy chit beo.
Kit qud cho thiy i ^ g chit beo tich luy dat cao nhit khi vi tio dupe nudi ciy d 730 lux (39,65%) va thip nhit d 9840 lux (20,96%). Tuy nbiln, ndng dO smh khii vi tao thu dupe khi nudi ciy d 1342 lux (0,306 g/L) cao hon nhilu so vdi khi nudi ciy d 730 lux (0,262 g/L) (Bing 1). Dilu nay li vi khi
dupe nudi cay d dilu kiln day dii dnh sang thi vi tao tap trung vao qua trinh phdn tach tl bao dl tang sd lupng bom la tich luy chat beo (Scott, Davey et al.. 2010; Cheirsilp and Torpee 2012). Tii dd cho thay cudng dp chieu sing 1342 lux dim bdo cbo vi tio Chlorella sp. vira phit triln tdt ve so lupng ciing nhu thu duoc khdi lupng chit beo ldn nhdt 0,11 g/L.
Tgp chiKhoa hgc Trudng Dgi hgc Can Tha Phin A: Khoa hoe Tv nhiin, Cdng nghi vd Mdi Irudng: 35 (2014): l-St Bang 1: Kha nang ti'ch liiy chit beo eua vi tao Chlorella sp. sau 8 ngay nuoi ciy
Cirirog dp sang (lux) 333 730 1342 9840 Nong dp sinh khdi (g/L)
Chit beo tich luy(%) Lupng chat beo (g/L)
0,187±0,004 0,262±0,008 30,62±0,92 39,65±4,36
0,06±0,0I 0,10±0,00
0,306±0,006 0,145±0,007 35,86±l,79 20,96tl,47
O,UJ:0,00 0,03±0,Q1 cda vi tao dat cao nhat vao ngay nudi cay thii 8 (35,86%) va ^am din d eic ngay nudi ciy tiip theo vi bat dau tir ngiy thii 9 li giai dogn phdt triin chdm do lupng dinh duong Uong mdi trudng nudi cay khdng edn du de cung cip cho cac qua trinh sinh tdng hpp chat beo ciia vi tio (Sharma 1998;
Takagi, Karseno el al, 2006; Tang, Chen et al, 2012; Wu, Chen et al, 2013). Do dd, thai gian de thu hoach vi tdo Chlorella sp. cho nhilu chit bio nhit li d ngay nudi ciy thOr 8.
Anh hudng ciia thdi gian tiip tyc dupe xera xet khi vi tao Chlorella sp. dupe nudi cay d dilu kiln nhiet dp 25°C, cudng dp chiiu sing trung bmh 1342 lux, bing nude cd dp mat 0%o frong khodng thdi gian tir 7-10 ngiy. Kit c^ua cho thiy ring ndng dp sinh khdi khdng thay ddi sau 8 ngay nudi cay hay ndi cich kliac vi tio suy tin sau ngay thii 8 (Bang 2). Diiu niy cd thi li do dinh duong frong mdi trudng khdng edn dii cung cdp cho sy sinh trudng va phdt Uiln ciia vi tio. Chdt beo tieh luy Bang 2: Kha ning ti'cfa luy chat beo cua vi tao Chlorella sp.
ThM gian nuoi cav (ngav) 7 N6ng dO sinh khoi (g/L) 0,252±0,008 Chit beo tfch My (%) 24,54±1,23 LUQng chat beo (g/L) 0,06±0,00
theo thoi gian nudi c4y 8 0,2S7±0,005 35,86±1,79 0,09±0,00
9 0,262*0,003 32,09±1,28 0,08±0,00
10 0,261±0,013 10,00*0,50 0,026±0,00 3.2 Anh hudng cua nhi^t do nuoi cay den
sy phit triin vi ti'ch liiy chat beo cua vi tao Chlorella sp.
Vi tdo Chlorella sp. dupe nudi cay d 2 diiu kiln nhiit dO ph6 biin la 25''C vd 30°C (vi khodng nhiet d§ thich hpp di nu6i eay vi tdo Chlorella sp. la tii 20°C - 35°C) vdi eiing cudng dp chiiu sang tmng binh 1342 lux, Uong nude cd dd mgn O96o va thu hogch d ngdy thii 8. Ndng dp sinh khii vi tao duoc nudi ciy d nhiet dp 30°C tang nhanh hon so vdi vi tdo dupe nudi cay d nhiet dd 25''C. Ndng dp sinh khoi dat cao nhit li 0,309 g/L sau 8 ngdy nudi ciy d nhi?t dp 30°C frong khi d 25°C thi ndng dp smh khii tdi da chi dat 0,257 g/L (Bang 3). Diiu ndy cho thay nhi^t dp thich hpp di thu nhiiu sinh khdi vi tdo Chlorella sp. la khodng 30''C vi ddy la nhiet dO phu hpp cho qui trinh phdn bio cua vi tio (Renaud, Thinh et ai, 2002; Kitaya, Azuma et ai, 2005; Convert!, Casazza et al, 2009; Roleda, Slocombe et al. 2013; Wu, Chen et al, 2013).
0 nhiit dp 30°C thi ndng dp sinh khdi vi tdo ting nhanh hon so vdi d 25°C, tuy nhien khi nang tich luy chit bio lai thip hon do cd thi d nhiet dp 25 °C thi qui trinh sinh tdng hpp chit beo diln ra tot hon so vdi d nhiet dd 30°C (Renaud, Thinh et al, 2002; Kitaya, Azuma et al, 2005; Converti, Casazza et ai, 2009; Roleda, Slocombe et al. 2013;
Wu, Chen et al, 2013). Lupng chit beo thu dupe eiia vi tdo khi nudi ciy d 25°C la 0,09 g/L do chit bio tich luy dgt 35,86%. Trong khi dd d 30°C thi lupng chat beo thu dupe chi la 0,08 g/L do chit
beo tich luy ehi dat 24,9% (Bing 3). Dilu ndy chiing td nhiet dd 25''C Ii nhiit dd thich hop de nudi cdy vi tdo Chlorella sp. vi cho lupng chit bio nhiiu hon (0,09 g/L).
Bang 3: Kha nang tfch Ifiy chit bio ciia vi tio Chlorella sp. dupe nudi d 2 diiu ki^n nhift dp khic nhau
Nhiet dp (°C) 25 30 Ndng dp sinh khdi (g/L) 0,257±0,008 0,309±0,015 Chit beo tich liiy (%) 35,86±1,79 24,85±1,23 Lupng chit beo (g/L) 0,09±0,00 0,08±0,00
3.3 Anh hiramg cua nude ditng d i nudi ciy din sy phat triln va ti'ch luy chat bio ciia vi tao Chlorella sp. --'^^^ili^^^^^v? -
Vi tio Chlorella sp. dupe nudi ciy d 2 logi nude khac nhau la nude cd dd min 25%o vi nude cd dp man 0%o d cimg nhiet dO trung bmh 25 °C vd cudng dd chiiu sdng tiling binh 1342 lux va thu hogch d ngiy thii 8. Ndng dd sinh khoi vl tdo dupe nudi ciy vdi nude co dO m ^ 25%o ting nhanh hon so vdi dupe nudi ciy vdi nude cd d0 mdn 0%o vi khi dupe nudi cay d mdi trudng cd dp m§n 2596o thi ham lupng mudi frong mdi trudng ciing ddng vai frd nhu mdt thanh phan dinh dudng gjiip vi tao phit triin tot hon (Takagi, Karseno et ai, 2006;
Harwati, Willke et ai. 2012). Trong dd, nong dp sinh khoi duac nudi ciy d nude ed dp m$n 25%o dat tdi da 0,320 g/L Uong khi d nude ed dp mgn 0%o thi ndng dd sinh khdi tdi da ehi dat 0,257 g/L (Bing 4). Tuy nhien, moi logi vi tdo si ed mpt gidi
7<Jp chi Khoa hgc Tniang Dgi hgc Cdn Thr Phdn A: Khoa hgc Tv nhiin, Cong nghi vd Mdi trudng: 35 (2014): 1-8 ban chiu min kMc nhau nln dd rain cua mdi
truong nudi ciy cd inh hudng rit ldn din sy phdt friin ciia vi tdo (Harwati, Willke et ai, 2012). Dieu niy cho thiy, nude ed dp rain 25%o thich h ^ de nudi ciy vi tio Chlorella sp. thu nhiiu sinh khdi.
Mgc du, ndr^ do sinh khdi thu dupe khi nudi ciy d nude cd dd man 2596o la 0,320 g/L nhiiu hon so vdi nudi ciy d nude ed dp mdn 0%o li 0,257 g/L nhung chdt bio tfch luy khi nudi ciy bdng nude 25%o l i 17% lai thip hon rit nhiiu so vdi khi nudi ciy bing nude cd dd man 0%o (35,86%) (Bang 4).
Tir do, ed thi kit lugn nude thich hpp dl nudi cay vi tio Chlorella sp. cho nhiiu chit beo li nude cd dO man 0%o vi ham lupng mudi frong mdi trudng cd inh hudng nhdt dinh din khi nang tieh luy chdt bio cua vi tio (Takagi, Karseno et ai, 2006;
Harwati, WiUke el ai, 2012).
Bang 4: Kha nang cung cip chit beo ciia vi tio Chlorella sp. duoc nudi ciy d 2 logi nude khac nhau
a $ mgn cua nirdc (%o) 25 0 Ndng dO sinh khdi (g/L) 0,320±0,0100,257±0,008 Chit beo tfch luy (%) 17,00±0,5l 35,86±1,79 Lupng chdt beo (g/L) 0,05i:0,01 0,09J:0,00
3.4 Anh hudng ciia diiu kiln nudi ciy din thanh phin chit bio vi tio Chlorella sp
Chat beo eiia vi tdo Chlorella sp. dupe nuoi cay d cdc dieu kiln phii hop (25°C, cudng dp chieu sing 1342 lux, nude cd dp man 0%o va thu hoach d ngay thii 8) dupe phan ti'ch bing mdy sic ki khi vi cho thiy rang thanh phin ciia chiing bao gdm 54,56% acid beo ty do, 9,97% monoglyceride, 10,43% diglyceride v i 18,58% triglyceride (Bang 5). Ham lupng acid beo ty do chilm khd cao ddi ivdiCvttz.a Chlorella sp. cd thi giy bdt lpi cho qua frinh tdng hpp biodiesel khi sii dyng xiic tac tmyln thdng li base.
Bang 5: Thanh phin ciia chat bio vi tao Chlorella sp.
Thanh phan Acid beo ty do Monoglyceride Diglyceride Triglyceride Thanh phdn khac
% khii lirgmg 54,56 9,97 10,43 18,59 6,46 Ngoai ra thanh phin cac acid beo eiia chit beo tii vi tdo Chlorella sp. cung bi dnh hudng bdi dilu kiln nudi cay nhu cudng dd chilu sang, nhiit dp nudi cdy vi mdi trudng nude nudi cay. Kit qua phdn tich dupe trinh bdy ttong Bang 6 vd eho thay rang khi vi tao dupe nudi d nhimg cudng dO sdng khac nhau thi thinh phan cic acid bio cua chit beo cung thay ddi. Trong dd, cudng d^ chiiu sang 1342 lux la dieu kiln nudi ciy phu hpp nhit vi tbanh pbin acid beo chu ylu li palmitic acid methyl ester (C16:0) va linoleie acid metiiyl ester (C18:2). 6 cudng dp chilu sing 7680 lux thi vi tio Chlorella sp. eiing tich liiy dupe cic thdnh phin cdn thilt nlu Uen vd nhilu nhdt la heptadecanoic acid metiiyl ester (C17:0) vdi 28,18%. Nhin chung, tiiinh pbin chit beo thu dupe tir vi tao c6 khi ning sir dyng di tdng hop biodiesel.
Bdng 6 eiing Uinli biy anh hudng ciia nhiet dp din thanh phin acid beo eiia chit beo. Khi dupe nudi cdy d 30°C thi thanh phdn dupe tich IQy cao nhit la C17;0 (30,89%) khic vdi tiianh phin chit beo thu dupe khi vi tio dupe nudi cdy d nhiet dp 25°C chu yiu la C16:0, va C18:2. Ngodi ra, mdi trudng nude nudi cay eung inh hudng rit ldn din thdnh phdn acid beo ciia chit beo tir vi tio Chlorella sp.. Cy thi, kbi vi tdo Chlorella sp. dupe nudi ciy d mdi trudng nude cd dd mgn 25%o thi hiu nhu vi tdo tich luy chdt beo cd thinh phin acid beo chii yeu li Ci7:0 vi C17:i. Do dd, tiiy vdo thdnh phdn chit beo mong muin md chiing ta cd dieu kiln nudi ciy phii hpp.
Tap chi Khoa hoc Tnrang Dgi hoc Cdn Tha Phdn A: Khoa hgc Tv nhien, Cong nghe vd Mdi truong- 35 (2014): / - # Bang 6: Thanh phan acid b£o ciia chat beo vi tao Chlorella sp. dirge nu5i ciy b nhung di^u Ici^n Ithaic
nhau. Trong do thoi gian nuoi diroc co dinh 8 ng^y Vlu t6 c6
dinh
NhiSt do 25"C, nir6^c0%)
AS. 1342 lux, nuitcO%>
N h i « d 0 2 5 " C , AS. 1342 lui Ytut6KS 333 lux 730 lux 1342 lux
C15:0(%) 12,92 7,43 C15:l (%) 5,60 5,71
C16:0(%) 18,12 10,57 38,32 C16:l (%) 6,38 CI6:2(%) - 6,88 C17:0 (%) 19,71 32,02
C17:l(%) 15,32 15,10
C18:0 (%) - 2,00 C18:l (%) 4,64
C18:2(%) 5,98 - 47,35 C20:0(%) 8,09 8,49 5,45 C20:l (%) - 7,97
C20:2 (%) 9,62 6,33
7680 lux 25°C ilTC 25%o 09«o 13,15
1,19 - 7,41 10,45 38,32 15,44 38,32 11,89
6,88 - - 6,88 28,18 30,89 66,00
6,66 - 16,83 26,59
0,52 2,00 2,00 21,56
19,55 47,35 - 47,35 5,45 10,36 5,45
7,21
642 ^ ^ ^ ^ (-/ khong phdt hien
4 KETLUIN
Nghien cmi cho thay rang vi tao Chlorella sp.
phat trien nhanh va kha nSng tich liiy chat beo cao khi dugc nuoi cay a cuong dQ chieu sang 1342 lux, nhiet do 25 "C, khoang tliai gian 8 ngay trong moi truong nuac co d6 man 0%o. Dong thai, thanh phin acid beo cija chat beo tU vi tao Chlorella sp. dugc nuoi cdy a dieu ki^n nay phan b6 tir CI5 dgn C20 va t|p trung nhilu li C16:0, CI6:2, C18:0 va C18:2. Day la loai chat beo chii yeu dl ting hgp biodiesel. Voi thanh phan acid beo tu do chilm hon 54%, cac phuang phap nhu xiic tac hai giai doan, tdi hgn hay can t6i hgn diu co thi su dung dl tong iigp biodiesel tu vi tao. Do d6, qua nghien cUu nay cho thiy vi tao cd tiem nang rat Ion ^k lim nguIn nguyen lieu ting hgp biodiesel.
TAI LIEU THAM KHAO 1. Cheirsilp, B. and S. Torpee (2012).
"Enhanced growth and lipid production of microalgae under mixotrophic culture condition: Effect of light intensity, glucose concenttation and fed-batch cultivation."
Bioresource Technology 110(0): 510-516.
2. Chen, L., T. Liu, et al. (2012). "Biodiesel production from algae oil high in free fatty acids by two-step catalytic conversion."
Bioresource Technology 111(0): 208-214.
3. Converti, A., A. A. Casazza, et al. (2009).
"Effect of temperature and nitrogen concentration on the growth and lipid content of Nannochloropsis oculata and
Chlorella vulgaris for biodiesel production."
Chemical Engineering and Processing:
Process Intensification 48(6): 1146-1151.
4. Harwati, T. U., T. Willke, et al. (2012).
"Characterization of the lipid accumulation in a tropical fresliwater microalgae Chlorococcum sp." Bioresource Technology 121(0): 54-60.
5. Ju, Y.-H., L. H. Huynh, et al (2013).
"Synthesis of biodiesel in subcritical water and methanol." Fuel 105(0): 266-271.
6. Kitaya, Y., H. Azuma, et al. (2005).
"Effects of temperature, C02/02 concentrations and light intensity on cellular multiplication of microalgae, Euglena gracilis." Advances in Space Research 35(9): 1584-1588.
7. Mata, T. M., A. A. Martins, et al. (2010).
"Microalgae for biodiesel production and other applications: A review." Renewable and Sustainable Energy Reviews 14(1):
217-232.
8. Renaud, S. M., L.-V. Thinh, et al. (2002).
"Effect of temperature on growth, chemical composition and fatty acid composition of tropical Australian microalgae grown in batch cultures." Aquaculture 211(1-4); 195-214.
9. Richmond, A. (2004). Handbook of Microalgal Culture: Biotechnology and Applied Phycoiogy. Cornwall, Wiley- Blackwell.
Tgp chi Khoa hgc Trudng Dgi hgc Cdn Tha Phdn A: Khoa hgc Tu nhiin, Cdng nghi vd Mdi trudng: 35 (2014): 1-8
10. Roleda, M . Y., S. P . Slocombe, et al.
(2013). "Effects of temperabjre andnufrient regimes on biomass and lipid production by six ole^mous microalgae in batch culture employing a two-phase cultivation sfrategy." Bioresource Technology 129(0):
439-449.
11. Saechetti, G., S. Maietti, et ai (2005).
"Comparative evaluation of 11 essential oils of different origin as fimctional antioxidants, antiradicals and antimicrobials in foods." Food Chemistry 91(4): 621-632.
12.Scott, S. A., M. P. Davey, etal (2010).
"Biodiesel from algae: challenges and prospects." Current Opinion in Biotechnology 21(3): 277-286.
13. Sharma (1998). Texbook of algal. Pillay, Tata Mc Graw library cataloguing in publication Data.
14. Takagi, M., Karseno, et ai (2006). "Effect of salt concenttation on intracellular
accumulation of lipids and ttiacylglyceride in marine microalgae Dunaliella cells."
Joumai of Bioscience and Bioengineering 101(3): 223-226.
15.Tang, H., M. Chen, etal (2012).
"Continuous microalgae cultivation in a photobioreaetor." Biotechnol Bioeng 109(10): 2468-2474.
16. Tsigie, Y. A., L. H. Huynh, et al (2012).
"In situ biodiesel production from wet Chlorella vulgaris under subcritical condition." Chemical Engineering Joumai 213(0): 104-108.
17. Wu, L. F., P. C. Chen, et al (2013). "The effects of nittogen sources and temperature on cell growth and lipid accumulation of microalgae." Intemational Biodeterioration
& Biodegradation 85(0): 506-510.
18. Zhou, X., H. Ge, et al (2013). "Evaluation of oil producing algae as potential biodiesel feedstock.
Bioresource Technology 134(0): 24-29.
