Ib qho ntawm cov tsav tsheb ntawm kev txhim kho kev lag luam nyob rau hauv ib nrab ntawm lub xyoo pua xeem yog plastics. Lawv yog cov pheej yig, yooj yim los tsim, resistant, elastic thiab, yog tias xoob, pob tshab, tab sis lawv muaj qhov tsis zoo, vim lawv tsis biodegradable, vim tsis muaj cov kab mob muaj sia tuaj yeem pub rau lawv.
Lawv cov kav ntev yog, tsis muaj qhov tsis ntseeg, yog ib qho kev sib tw loj uas peb ntsib, txij li qhov tsawg kawg ntawm plaub puas thiab tsib caug xyoo yuav tsum dhau mus rau cov polymers kom pib cov txheej txheem tawg ntawm qib molecular.
Nws tau kwv yees tias ntau dua 300 lab tons ntawm cov yas tau tsim thoob ntiaj teb, ntawm 90% yog muab los ntawm cov roj av thiab ib feem me me, kwv yees li 15%, yuav rov qab los thiab rov qab los ntawm thoob ntiaj teb.
Ntawm cov nyiaj astronomical ntawd, qhov nruab nrab ntawm yim lab tons yuav ploj mus txhua xyoo nyob rau hauv peb cov dej hiav txwv, qhov chaw uas lawv tog, sau nyob rau hauv sediments los yog xaus rau kev koom ua ke rau hauv tib neeg cov zaub mov saw.
Cov kev kwv yees luv luv tsis yog qhov muaj txiaj ntsig zoo; qee lub suab tso cai kwv yees tias los ntawm xyoo 2050 cov khoom pov tseg yas yuav ncav cuag kaum peb billion tons. Ib daim duab uas, tsis muaj qhov tsis ntseeg, yuam kom peb ua kom muaj zog thiab ceev ceev.
Ua tsaug rau nws, nyob rau hauv 2016 peb nrhiav tau lub hav zoov ntawm ib tug ua tau phooj ywg thiab, raws li tau tshwm sim ntau zaus nyob rau hauv keeb kwm ntawm kev tshawb fawb, serendipity tau ua lub luag haujlwm tseem ceeb. Xyoo no ib pab neeg ntawm cov kws tshawb fawb Nyij Pooj tau tshawb xyuas cov kab mob hauv cov nroj tsuag rov ua dua tshiab hauv nroog Sakai, Nyiv. Lub sijhawm no peb tau txheeb xyuas cov kab mob uas tau muab rho tawm los ntawm polyethylene terephthalate (PET) pov tseg ntxiv rau cov khoom (ethylene glycol thiab terephthalic acid).
Xav tsis thoob, lawv pom tias cov kab mob, uas yog hu ua Ideonella sakaiensis, muaj peev xwm siv PET ua qhov tseem ceeb ntawm carbon. Qee lub sij hawm tom qab ntawd nws tau pom tias cov kab mob muaj ob lub noob tseem ceeb uas tso cai rau nws mus 'dev' tus tsiaj: PETase thiab mono (2-hydroxyethyl) terephthalate hydrolase.
Txoj kev cia siab
Qhov kev tshawb pom ntawm cov kab mob metabolic tau piav qhia tias Ideonella tau tsim nws qhov chaw nyob hauv cov nroj tsuag rov ua dua tshiab, tab sis qhov tseem yuav tsum tau daws tsis tau yog txoj hauv kev uas cov kab mob tau hloov zuj zus los hloov cov yas, uas tau patented hauv kaum xyoo ntawm lub forties. ntawm lub xyoo pua xeem, nyob rau hauv nws cov khoom noj.
Cov kab mob muaj peev xwm hloov PET rau hauv poly (3-hydroxybutyrate) - tseem hu ua PHB - uas yog hom yas biodegradable. Qhov txaus nyiam tshaj plaws ntawm zaj dab neeg no yog tias nws tau kwv yees tias PET degrades ntawm tus nqi ntawm 0,13 mg ib square centimeter ib hnub twg, ntawm qhov kub ntawm 30ºC, qhov kev tshem tawm uas dhau los ua 'qeeb heev'.
Muaj hmoo luag ntxhi rau peb dua hauv 2018 thaum cov kws tshawb fawb ntawm University of Postmouth (University of Postmouth) los ntawm lub caij nyoog tsim cov enzyme uas txhim kho cov kab mob PETase.
Lub sijhawm no, tau sim ua ib kauj ruam ntxiv los ua kom nws cov khoom tsim tau zoo los ntawm 'ntxig' cov enzyme mutant rau hauv cov kab mob Extremophilic, muaj peev xwm tiv taus qhov kub siab tshaj 70ºC, ib daim duab uas PET muaj kuab heev. Qhov 'hloov' no tuaj yeem ua kom cov txheej txheem degradation nce mus txog 10%.
Tag nrho cov kev tshawb pom no tuaj yeem ua rau peb so thiab qhib lub qhov rais rau kev cia siab, txij li cov kab mob 'dev cov yas' yuav yog ib feem ntawm kev daws teeb meem ib puag ncig los ntawm plastics.
Yawg Jara
Pedro Gargantilla yog tus kws kho mob hauv tsev kho mob El Escorial (Madrid) thiab tus sau phau ntawv nrov.
