es ▁where ▁prim ing ▁sugar ▁is ▁used ▁to ▁carbon ate ▁the ▁be er . ▁The ▁optim um ▁growth ▁temperature ▁is ▁ 2 5 ▁to ▁ 3 0 ▁degrees ▁Cel si us . ▁ ▁Eth an ol ▁production ▁Z ym omon as ▁mobil is ▁de gr ades ▁sug ars ▁to ▁py ru v ate ▁using ▁the ▁Ent ner - D oud or off ▁path way . ▁The ▁py ru v ate ▁is ▁then ▁fer ment ed ▁to ▁produce ▁eth an ol ▁and ▁carbon ▁dio x ide ▁as ▁the ▁only ▁products ▁( anal og ous ▁to ▁ye ast ). ▁ ▁The ▁advantages ▁of ▁Z . ▁mobil is ▁over ▁S . ▁c ere vis iae ▁with ▁respect ▁to ▁producing ▁bio eth an ol : ▁higher ▁sugar ▁u pt ake ▁and ▁eth an ol ▁yield ▁( up ▁to ▁ 2 . 5 ▁times ▁higher ), ▁lower ▁bi om ass ▁production , ▁higher ▁eth an ol ▁toler ance ▁up ▁to ▁ 1 6 % ▁( v / v ), ▁does ▁not ▁require ▁controlled ▁addition ▁of ▁o xygen ▁during ▁the ▁fer ment ation , ▁ ▁However , ▁in ▁spite ▁of ▁these ▁attract ive ▁advantages , ▁several ▁factors ▁prevent ▁the ▁commercial ▁usage ▁of ▁Z . ▁mobil is ▁in ▁cell ulos ic ▁eth an ol ▁production . ▁The ▁for em ost ▁hur d le ▁is ▁that ▁its ▁substr ate ▁range ▁is ▁limited ▁to ▁gl uc ose , ▁f ruct ose ▁and ▁suc rose . ▁Wild - type ▁Z . ▁mobil is ▁cannot ▁fer ment ▁C 5 ▁sug ars ▁like ▁x y