YAmylose vs Amylopectin
Starch yog ib qho carbohydrate uas yog categorized li polysaccharide. Thaum kaum lossis ntau dua ntawm cov monosaccharides koom nrog glycosidic bonds, lawv hu ua polysaccharides. Polysaccharides yog cov polymers thiab, yog li ntawd, muaj qhov hnyav dua molecular, feem ntau ntau dua 10000. Monosaccharide yog cov monomer ntawm cov polymer no. Muaj peev xwm muaj polysaccharides ua los ntawm ib qho monosaccharide thiab cov no hu ua homopolysaccharides. Cov no tuaj yeem raug cais raws li hom monosaccharide. Piv txwv li, yog tias monosaccharide yog piam thaj, ces chav tsev monomeric hu ua glucan. Starch yog glucan li ntawd. Nyob ntawm txoj kev uas cov piam thaj molecules txuas rau ib leeg, muaj cov ceg thiab tsis muaj ceg nyob hauv cov hmoov txhuv nplej siab. Cov hmoov txhuv nplej siab dav tau hais tias yog ua los ntawm amylose thiab amylopectin uas yog cov chains loj ntawm cov piam thaj.
Amylose
Qhov no yog ib feem ntawm cov hmoov txhuv nplej siab, thiab nws yog polysaccharide. D-glucose molecules txuas rau ib leeg txhawm rau tsim cov qauv kab hu ua amylose. Ntau cov piam thaj molecules tuaj yeem koom rau hauv kev tsim cov amylose molecule. Tus lej no tuaj yeem ua tau los ntawm 300 mus rau ntau txhiab. Thaum D-glucose molecules nyob rau hauv daim ntawv cyclic, tus naj npawb 1 carbon atom tuaj yeem tsim ib daim ntawv cog lus glycosidic nrog 4th carbon atom ntawm lwm cov piam thaj molecule. Qhov no yog hu ua α-1, 4-glycosidic daim ntawv cog lus. Vim hais tias ntawm no linkage amylose tau txais ib tug linear qauv. Nws tuaj yeem muaj peb hom amylose. Ib qho yog amorphous tsis zoo, thiab muaj ob daim ntawv helical. Ib cov saw amylose tuaj yeem khi nrog lwm cov saw amylose lossis nrog lwm cov tshuaj hydrophobic xws li amylopectin, fatty acid, aromatic compound, thiab lwm yam. Thaum tsuas yog amylose nyob rau hauv cov qauv, nws yog nruj nreem ntim vim lawv tsis muaj ceg. Yog li lub rigidity ntawm tus qauv yog siab.
Amylose ua 20-30% ntawm cov qauv ntawm cov hmoov txhuv nplej siab. Amylose yog insoluble hauv dej. Amylose kuj yog vim li cas rau insolubility ntawm starch. Nws kuj txo cov crystallinity ntawm amylopectin. Hauv cov nroj tsuag, amylose ua haujlwm ua lub zog cia. Thaum amylose degraded rau hauv cov ntawv me me carbohydrate li m altose, lawv tuaj yeem siv los ua lub zog. Thaum ua qhov kev sim iodine rau cov hmoov txhuv nplej siab, cov iodine molecules haum rau hauv cov qauv helical ntawm amylose, yog li muab cov xim dub / xiav.
YAmylopectin
Amylopectin yog cov ceg ntoo polysaccharide uas tseem yog ib feem ntawm cov hmoov txhuv nplej siab. 70-80% ntawm cov hmoov txhuv nplej siab muaj amylopectin. Ib yam li hauv amylose, muaj qee cov piam thaj molecules txuas nrog α-1, 4-glycosidic bonds tsim cov qauv ntawm amylopectin. Txawm li cas los xij, ntawm qee cov ntsiab lus α-1, 6-glycosidic bonds kuj raug tsim. Cov ntsiab lus no yog lub npe hu ua branching point. Kev faib tawm yog ua txhua txhua 24 mus rau 30 cov piam thaj. 2, 000 txog 200, 000 cov piam thaj hauv cov ntshav tau koom nrog hauv kev tsim ib qho amylopectin molecule. Vim li no, branching rigidity ntawm amylopectin qis dua, thiab nws yog soluble hauv dej. Amylopectin tuaj yeem yooj yim degraded siv enzymes. Qhov no yog cog lub zog cia molecule thiab kuj yog ib qhov chaw ntawm lub zog.
Dab tsi yog qhov txawv ntawm Amylose thiab Amylopectin?
• Amylopectin yog ib ceg polysaccharide thiab amylose yog linear polysaccharide.
• Tsuas yog α-1, 4-glycosidic bonds koom nrog hauv kev tsim cov amylose, tab sis ob qho tib si α-1, 4-glycosidic bonds thiab α-1, 6-glycosidic bonds muaj nyob rau hauv amylopectin.
• Amylose yog nruj dua amylopectin.
• Amylose tsis yooj yim zom dua li amylopectin.
• Amylopectin yog soluble hauv dej thaum amylose tsis yog.
• Hauv cov hmoov txhuv nplej siab, 20-30% ntawm cov qauv yog tsim los ntawm amylose, whereas 70-80% yog tsim los ntawm amylopectin.
