Khắc phục các trở ngại trong quá trình sản xuất nhiên liệu sinh học xenluloza

I BMCtBltr<br /> <br /> KHAC PHIJC CAC TRD IMEiAl TROIVG QUA TRIIMH<br /> SAIV XUAT IXIHIEIV LIEU SIIVH HOC XEIVLULOZA<br /> Cac nhd nghien cuu thong bdo ve mot logi ndm men m&i dugc tgo ra gdn day co the lien<br /> tuc hdp thu hai logi dudng tu thuc vdt de sdn xudt ethanol. Hai logi duong ndy Id glued,<br /> duong 6 cacbon ldm len men tuang ddi di; vd xyloza, duang 5 cacbon kho sddung han nhieu<br /> trong sdn xudt ethanol. Logi ndm men m&i ndy, dugc tgo ra bdng su ket hgp, tdi uu hod vd<br /> sd dung nhung tie'n bg m&i nhdt, gidm b&t hay hgn che tinh khong hieu qud cua phuang<br /> phdp sdn xudt nhien lieu sinh hgc hien nay.<br /> <br /> GHIEN ciiu dugc dang tren Tap chi<br /> <br /> N Proceedings of the National Academy<br /> of Sciences. Cac nam men dugc nuoi<br /> ldn blng dudng va tao ra nhieu loai phe pham,<br /> mot sd do rat hiiu ich ddi vdi con ngudi. Nam<br /> men Saccharomyces cerevisiae dugc sii dung<br /> tir nhieu the ky trong lam rugu bia va trong quy<br /> trinh san xuat ethanol va dioxit cacbon vi no<br /> lam len men mgt each co hieu qua cac loai<br /> dudng. Nganh cong nghiep nhien lieu sinh hgc<br /> sit dung loai nam men nay de bien ddi ducrng<br /> thanh ethanol sinh hgc. Trong khi nam men S. Yong-Su Jin, Giao su khoa hoc thye pham va dinh dudng ciia<br /> Illinois (dimg giua), Suk-Jin Ha , nghien cuu sau tien si (ben<br /> cerevisiae rat tdt trong hap thu gluco, khdi ket trai), nghien cifu sinh Soo Rin Kim va cac cpng sy da bien doi<br /> cau gdm xenlulo va dudng nguyen thuy trong mot loai nam men trong san xuat ethanol tu sinh khdi xenlulo.<br /> thuc vat, thi no khong the hap thu xy-16-za, Anh: L, Brian Stautfer, U, of I. News Bureau,<br /> thanh phan thir yeu nhung quan trgng cua<br /> nhien lieu sinh hgc.<br /> lignocellulose tao thanh than va la cay. Hau het<br /> Jin va cac cong sir mudn tao ra loai nam<br /> cac loai nam men dugc tao ra de chuyen hoa<br /> xy-16-za thuc hien rat cham. men tieu thu nhanh chong va hieu qua ca hai<br /> loai dudng ngay lap tiic, mgt quy trinh dugc ggi<br /> "Xy-16-za la mgt loai dudng gd; dudng la ddng len men.<br /> cacbon 5 co rat nhieu trong sinh khdi nhung<br /> Trong mgt quy trinh dieu chinh nam men<br /> khong CO trong thuc pham cua chiing ta,"<br /> gdc, Jin va cong su bien ddi no thanh nam men<br /> Yong-Su Jin, giao su khoa hgc thuc pham va<br /> tieu thu ca hai loai dudng nhanh hon va hieu<br /> dinh duong ngudi tai Illinois cho biet. "Hau het<br /> qua hon bat cii loai nam men nao hien dang<br /> nam men khong the lam len men xy-16-za."<br /> dugc sir dung trong nganh cong nghiep nhien<br /> Mpt phan ldn ciia thach thiic ddi vdi cac loai lieu sinh hgc. Tren thuc te, loai nam men mdi<br /> nam men dugc thay ddi de len men xy-16-za la nay chuyen ddi lien tuc cellobiose (tien chat<br /> chiing se hiit tit ca gluco trong mgt hdn hgp ciia gluco) va xy-16-za thanh ethanol nhanh<br /> trudc khi chiing tiep xiic vdi xy-16-za. He<br /> nhu khi no co the len men chi mgt trong hai<br /> thdng chuyen chd gluco tren he. mat ciia nam<br /> loai dudng.<br /> men ua ket hgp vdi gluco hon. Loai nam men<br /> nay chuyen hoa xy-16-za rat cham ciing lam "Neu ban len men blng each sir dung rieng<br /> tang dang ke chi phi cho qua trinh san xult cellobiose hay xy-16-za thi se mat 48 gid,"<br /> Suk-Jin Ha. lac gia chinh cua bao bao cho biet.<br /> <br /> <br /> KCM-1.2011 43<br />  BUI cd BIET<br /> <br /> <br /> IVAO TIEP TUC PHAT TRIEIV DEIV DO TUOI 3 0 VA 4 0<br /> • •<br /> <br /> <br /> Nghien cihi mdi ddy tgi Anh cho thdy sau thai thadu vd tudi day thi, ndo vdn tiip tuc phdt<br /> trien vd nd chua ngimg phdt trien hodn todn khi nguai ta d vdo do tudi 30 vd 40. Nhitng phdt<br /> Men ndy ngugc lgi v&i edc ly thuyit hien cho rdng ndo ngiing phdt triin sam hon rdt nhieu.<br /> <br /> <br /> <br /> G<br /> IAO su Sarah-Jayne Blakemore, nha<br /> khoa hgc thin kinh tai Vien Khoa hgc<br /> than kinh nhan thiic, trudng DH<br /> / > ' { 101)01 L) t,«i<br /> London, cho biet, cho den khoang mgt thap ky<br /> tnrdc day, nhieu nha khoa hgc cho ring nao<br /> ngudi ngimg phat trien vao diu thdi ky tha<br /> au," nhung nghien ciiu gin day phat hien ra r:^:r<br /> ring nhieu khu vuc trong nao vin tiep tuc phat<br /> trien mgt thdi gian dai sau do.<br /> Viing vo nao dudi tran la viing phia trudc<br /> cua nao nim ngay dudi tran va la vimg nao co nao cho thay viing vd nao dudi tran vin tiep tuc<br /> thdi gian phat trien lau nhat. No la vung nao thay ddi hinh dang khi con ngudi d do tudi 30<br /> quan trgng thuc hien cac chiic nang nhan thuc va 40. Ba noi ring khu vuc nay ciia nao bit dau<br /> cao cap nhu dat ke hoach va dua ra cac quyet thay ddi vao giai doan diu thdi tho au va sau<br /> dinh va no cung la viing quan trgng thuc hien<br /> do dugc td chiic lai vao cudi giai doan day thi<br /> cac hanh vi xa hgi, nhan thiic xa hgi, thong<br /> nhung sau do vin tiep tuc thay ddi.<br /> cam, hieu biet cung nhu giao tie'p xa hgi va<br /> hinh thanh ca tinh. Giao su Blakemore cho biet Nghien ciiu nay cd the giai thich ly do tai<br /> vung vo nao dudi tran la phan nao lam cho sao mgt sd ngudi trudng thanh doi khi hanh<br /> ehung ta trd thanh con ngudi vi co sir lien ket dgng nhu thanh thieu nien, hdn ddi hay cau<br /> chat che giiia viing nao dudi tran va tinh each kinh ne'u khong theo y ciia hg, va tai sao mpt sd<br /> ciia con ngudi. ngudi vin vung ve trong giao tiep mac du<br /> khong con tre nira.<br /> Giao su Blakemore cho biet, chup elt ldp<br /> N.L.H. (theo PhysOrg.com, 22/12/2010)<br /> <br /> "Nhung neu ban thuc hien len men ddng thdi blng each tao ra nhieu thay ddi then chdt ddi<br /> blng cellobiose va xy-16-za, lugng dudng tang vdi sinh vat. Diu tien, hg cho xelobioza vao<br /> gap doi dugc tieu thu trong ciing mgt lugng trong nam men. Xelobioza, m6t thanh phin ciia<br /> thdi gian va san sinh ra nhieu hem gap doi vach te bao thuc vat, gdm hai loai dudng lien<br /> lugng ethanol. Do la do tac dgng ciia viec len ket vdi nhau. Cellobiose theo truyen thdng dugc<br /> men ddng thdi." bien ddi thanh gluco trudc khi tham nhap vao<br /> Loai nam men mdi nay hieu qua hon it nhat trong te bao thong qua cac chat chuyen chd<br /> 207o trong viec chuyen ddi xy-16-za thanh gluco de bien ddi thanh ethanol. Co mgt chat<br /> ethanol hon cac loai nam men khac, lam cho no chuyen chd cellobiose co nghia la loai nam men<br /> trd thanh loai nam men len men xy-16-za tdt dugc bien ddi nay c6 the mang cellobiose true<br /> tiep vao te bao nay. Chi sau khi cellobiose vao<br /> nhat, Jin noi.<br /> ben trong te bao, no dugc bien ddi thanh gluco.<br /> Nhom nghien ciiu dat dugc cac ket qua nay LH. (theo PhysOrg.com, 27/12/2010)<br /> <br /> 44<br /> KCM-1.2011<br />