CYANOCOBALAMIN (vitamin B12)
Ọdịdị na Njirimara
Ngwaahịa a bụ ntụ kristal crystalline ma ọ bụ kristal, ọ naghị esi isi, ọ naghị atọ ụtọ ma nwee ike ịkpalite mmiri mmiri. Ọ na-agbaze ntakịrị na mmiri ma ọ bụ ethanol, ọ naghị agbaze na chloroform ma ọ bụ ether. Ọ na-eguzogide okpomọkụ, mana ọ nwere ike ọ gaghị arụ ọrụ mgbe a na-ekpughe ya na ihe ndị na-eme ka oxidation ma ọ bụ belata (dịka vitamin C ma ọ bụ hydrogen peroxide, wdg), nnu ígwè dị arọ na asịd siri ike na alkalis siri ike.
Nhazi Kemịkalụ
Vitamin B12 bụ ngwakọta equioctaphedral nwere ion cobalt. Nhazi etiti ya bụ mgbanaka corrin dị larịị nke nwere pyrroles anọ jikọtara ọnụ. Mkpụrụ ndụ vitamin B12 nwere ihe dị ka akụkụ atọ: mgbanaka gourin nke atọm N anọ na ion cobalt etiti jikọtara ọnụ; 5,6-dimethylbenzimidazole (5,6-dimethylbenzimidazole, DMBI) jikọtara na atọm N-7 na ion cobalt dị ka molekul vitamin B 12 nke ligands dị ala (α). Na mgbakwunye, DMBI jikọtara na aminopropanol site na otu phosphate, aminopropanol jikọtara ọnụ na propionic acid single yinye na pyrrole D; otu adenosyl ma ọ bụ otu methyl. Ọ jikọtara ya na ion cobalt iji mepụta ligand elu (β) nke molekul vitamin B12. Ụdị ihe dị iche iche nke vitamin B12 na-etolite mgbe otu akwụkwọ kemịkalụ dị iche na akwụkwọ kemịkalụ dị elu na axis nke mgbanaka goline. A na-ejikọ otu hydroxyl (-OH) na ion cobalt dị na mgbanaka gluline iji mepụta hydroxycobalamin. N'otu aka ahụ, a na-ejikọ deoxyadenosine (5'-deoxyadenosyl), methyl (-CH3), cyanide (-CN) na ion cobalt iji mepụta adenosine cobalt n'otu n'otu. Amine (deoxyadenosylcobalamin), methylcobalamin (methylcobalamin) na cyanocobalamin (cyanocobalamin). N'okike, ụdị ikpeazụ nke vitamin B12 biosynthesis nke microorganisms na-emepụta bụ adenosine cobalamine (coenzyme B12), methyl cobalamine na hydroxycobalamine. Agbanyeghị, n'ihi na ihe onwunwe ha adịghị akwụsi ike nke ukwuu, a na-etinye sodium cyanide n'ụzọ aka na-arụ ọrụ na usoro nhicha ụlọ ọrụ iji gbanwee ụdị vitamin B12 sitere n'okike ka ọ bụrụ cyanocobalamin kwụsiri ike karị.
Ọrụ Ahụ́ Ike
Meziwanye ọnụego ojiji nke folic acid, mepụta meththionine (nke sitere na cysteine dị elu) na choline na folic acid, yana imepụta cyanocobalamin precursors dị ka methyl coballamin na coenzyme B12 n'usoro mmepụta nke prine na pyrimidine, ma sonye na usoro methylation nke ọtụtụ ihe dị mkpa. Mgbe vitamin B12 adịghị ezu, ọrụ nke ibufe otu methyl site na methyl tetrahydrofolic acid na-ebelata, na-eme ka folic acid bụrụ ụdị a na-apụghị iji, na-eduga na ụkọ folic acid. Nọgide na-enwe metabolism na ọrụ nke mkpuchi myelin akwara. Enweghị vitamin B12 nwere ike ibute nsogbu akwara, mmebi ọkpụkpụ azụ, na akwụkwọ kemịkalụ nwere ike ibute nnukwu mgbaàmà uche. Enweghị vitamin B12 nwere ike ibute neuritis nke akụkụ. Ihe ngosi mbụ nke enweghị vitamin B12 na ụmụaka bụ ọnọdụ uche na-adịghị mma, ngosipụta nwayọ, mmeghachi omume nwayọ, na n'ikpeazụ ibute anaemia. Na-akwalite mmepe na ntozu okè nke mkpụrụ ndụ ọbara uhie. A na-agbanwe Methylpropandiyl coenzyme A ka ọ bụrụ succinoyl coenzyme A ma na-esonye na okirikiri tricarboxylic acid, nke succinyl coenzyme A na-ejikọta ya na mmepụta heme. Vitamin B12 na-esonyekwa na mmepụta nke deoxynucleic acid (DNA), metabolism nke abụba, carbohydrates na protein, ma na-eme ka mmepụta nke nucleic acid na protein dịkwuo elu.
