I-Vitamin E iyivithamini engenaphunga futhi engenambitheki enamafutha aphuzi ancibilikayo ane-antioxidant, anticancer, anti-inflammatory kanye neminye imisebenzi. Ngokwesakhiwo sayo samangqamuzana, ingahlukaniswa izigaba ezimbili: tocopherols kanye tocotrienols. Isigaba ngasinye sihlukaniswe ngezinhlobo ezine ngokusekelwe endaweni ye-methyl eringini ye-chromophore: i-alpha, i-beta, i-gamma, ne-delta [1-2]. Izithako ezihlobene ne-tocopherols, njenge-tocotrienols, zinomsebenzi othile lapho izingxenye ezihlukile zihlukile, kodwa umsebenzi we-tocopherols uyancipha kakhulu.

Kokubili i-tocopherol ne-tocotrienol inemiphumela enamandla ye-antioxidant. Ngenxa yomsebenzi we-alpha tocopherol protein transfer (alpha TP) kanye ne-tocopherol binding protein (TBP) emzimbeni, i-tocopherol imuncwa kalula futhi isetshenziswe ngumzimba. Ngakho-ke, i-alpha tocopherol ibhekwa njengokubonakaliswa okuyinhloko komsebenzi we-antioxidant we-vitamin E emzimbeni. I-Alpha tocopherol, enefomula yamangqamuzana engu-C29H50O2 kanye nesisindo samangqamuzana angu-430.5, ihlukaniswe yaba izinhlobo ezimbili ngokusekelwe emthonjeni wayo: yemvelo kanye neyokwenziwa, echazwe njengohlobo lwe-D kanye nohlobo lwe-L, ngokulandelanayo. I-alpha tocopherol yemvelo iku-R conformation (RRR), kuyilapho i-alpha tocopherol eyenziwe ngokuzenzakalelayo iku-RS conformation (RRR, RSR, RRS, RSS, SRR, SSR, SRS, SSS). I-conformation ihlobene nomsebenzi wayo, futhi izifundo zithole ukuthi i-alpha tocopherol kuphela ene-2R noma ngaphezulu engasetshenziswa futhi amuncwa umzimba. Ngakho-ke, i-alpha tocopherol yemvelo inenani eliphezulu lokudla okunempilo futhi iphephile kune-alpha tocopherol eyenziwe ngokwenziwa.