I-Vitamin C inomphumela wokuvimbela nokwelapha i-ascorbic acid, yingakho yaziwa nangokuthii-ascorbic acidfuthi iyivithamini encibilika emanzini. I-vitamin C yemvelo itholakala kakhulu ezithelweni ezintsha (ama-apula, amawolintshi, i-kiwifruit, njll.) kanye nemifino (utamatisi, ukhukhamba, neklabishi, njll.). Ngenxa yokuntuleka kwe-enzyme eyinhloko esinyathelweni sokugcina se-vitamin C biosynthesis emzimbeni womuntu, okungukuthi.I-L-glucuronic acid 1,4-lactone oxidase (GLO),uvithamini C kufanele athathwe ekudleni.
Ifomula yamangqamuzana kavithamini C yi-C6H8O6, okuyi-ejenti yokunciphisa enamandla. Amaqembu amabili e-enol hydroxyl kuma-athomu ekhabhoni angu-2 no-3 ku-molecule ahlukaniswa kalula futhi adedele i-H+, ngaleyo ndlela akhiphe i-oxidizing yakhe uvithamini C. ukudlala indima ebalulekile emzimbeni womuntu. Uma isetshenziswa emkhakheni wezimonyo, uvithamini C unemisebenzi efana nokwenza mhlophe nokukhuthaza ukwakheka kwe-collagen.
Ukusebenza kwe-vitamin C
isikhumba sibe mhlophe
Zimbili izindlela ezisemqoka ezenza ngazouvithamini Cinomphumela omhlophe esikhumbeni. Indlela yokuqala ukuthi uvithamini C anganciphisa i-oxygen melanin emnyama ngesikhathi sokukhiqizwa kwe-melanin ukuze ehlise i-melanin. Umbala we-melanin unqunywa isakhiwo se-quinone ku-molecule ye-melanin, futhi uvithamini C unempahla ye-ejenti yokunciphisa, enganciphisa isakhiwo se-quinone sibe isakhiwo se-phenolic. Indlela yesibili ukuthi i-vitamin C ingabamba iqhaza ku-metabolism ye-tyrosine emzimbeni, ngaleyo ndlela yehlise ukuguqulwa kwe-tyrosine ibe yi-melanin.
i-antioxidant
Ama-radicals wamahhala ayizinto eziyingozi ezikhiqizwa ukusabela komzimba, ezinezakhiwo ezinamandla ze-oxidizing futhi ezingalimaza izicubu namaseli, okuholela ochungechungeni lwezifo ezingapheli.Ivithamini Ciyi-scavenger yamahhala encibilikayo emanzini engaqeda ama-radicals mahhala afana - OH, R -, no-O2- emzimbeni, edlala indima ebalulekile emsebenzini we-antioxidant.
Thuthukisa ukuhlanganiswa kwe-collagen
Kunezincwadi ezibonisa ukuthi ukusetshenziswa kwansuku zonke kwezakhi eziqukethe i-5% L-ascorbic acid esikhumbeni kungakhuphula amazinga okuvezwa kwe-mRNA ohlobo I nohlobo lwe-collagen III esikhumbeni, kanye namazinga wokuvezwa kwe-mRNA ezinhlobo ezintathu zama-invertase, i-carboxycollagenase. , i-aminoprocollagenase, ne-lysine oxidase nawo anda ngezinga elifanayo, okubonisa ukuthi uvithamini C ungakhuthaza ukwakheka kwe-collagen esikhumbeni.
Umphumela we-Prooxidation
Ngaphezu kwemiphumela ye-antioxidant, i-vitamin C iphinde ibe nomthelela we-prooxidant phambi kwama-ion ensimbi, futhi ingabangela i-lipid, i-protein oxidation, nokulimala kwe-DNA, ngaleyo ndlela kuthinte ukubonakaliswa kwezakhi zofuzo. I-Vitamin C inganciphisa i-peroxide (H2O2) ku-hydroxyl radical futhi ikhuthaze ukwakheka komonakalo we-oxidative ngokunciphisa i-Fe3+kuya ku-Fe2+ kanye ne-Cu2+ ku-Cu+. Ngakho-ke, akunconywa ukufaka uvithamini C kubantu abane-iron ephezulu noma labo abanezimo ze-pathological ezihlobene nokugcwala kwensimbi njenge-thalassemia noma i-hemochromatosis.
Isikhathi sokuthumela: Apr-10-2023
