Qhov Tseem Ceeb Qhov txawv - Vitamin A vs. Beta Carotene
Zoo li muaj ntau qhov tsis meej pem txog qhov sib txawv ntawm vitamin A thiab beta carotene. Vitamin A yog ib tug fat-soluble vitamin thiab sawv cev rau ib pawg ntawm unsaturated khoom noj khoom haus organic composites; uas muaj xws li retinol, retinal, retinoic acid, thiab ntau provitamin A carotenoids, thiab beta-carotene. Vitamin A yog qhov tshwj xeeb tshaj yog rau kev noj qab haus huv ntawm lub qhov muag, lub ntsws, pob txha, tawv nqaij, tiv thaiv kab mob, thiab kev tsim cov protein. Beta-carotene yog ib qho pro-vitamin A thiab ntau tshaj thiab paub zoo carotene. Qhov no yog qhov sib txawv tseem ceeb ntawm vitamin A thiab beta carotene. Beta-carotene yog tsim nyob rau hauv liab, txiv kab ntxwv, thiab daj xim txiv hmab txiv ntoo thiab zaub. Pro-vitamin A (beta-carotene thiab lwm yam carotene) tuaj yeem hloov pauv hauv tib neeg lub cev rau hauv retinol (vitamin A). Hauv tsab xov xwm no, cia peb piav qhia qhov sib txawv ntawm cov vitamin A thiab beta-carotene raws li lawv qhov kev npaj siv thiab lwm yam tshuaj lom neeg.
Vitamin A yog dab tsi?
Vitamin A (retinol) yog vitamin thiab tseem ceeb rau lub neej thiab kev noj qab haus huv tag nrho. Nws yog ib tsev neeg ntawm cov tshuaj hu ua pro-vitamin A thiab raws li pre-formed vitamin A. Preformed vitamin A twb tsim raws li vitamin A thiab nws muaj ntau yam ntaub ntawv ntawm retinol, retinal thiab retinoic acid. Txawm li cas los xij, lo lus retinol feem ntau siv los ntawm cov kws tshawb fawb thaum xa mus rau vitamin A. Preformed vitamin A yog keeb kwm hauv cov khoom tsiaj nkaus xwb, xws li ntses thiab khoom noj siv mis. Ntau cov vitamin A muaj xws li carotenoids thiab beta-carotene, thiab lawv tuaj yeem hloov mus ua cov vitamin ua ntej hauv tib neeg lub cev.
Vitamin A muaj ntau yam haujlwm hauv tib neeg lub cev. Nws yog qhov tseem ceeb rau kev loj hlob thiab kev loj hlob, rau kev saib xyuas ntawm lub cev tiv thaiv kab mob thiab kev pom zoo. Vitamin A yog xav tau los ntawm retina ntawm lub qhov muag nyob rau hauv daim ntawv ntawm retinal, uas reacts nrog protein opsin rau synthesize rhodopsin, lub teeb-rhiab molecule yuav tsum tau rau ob qho tib si lub teeb pom kev zoo thiab xim tsis pom kev. Ntxiv rau qhov ntawd, ib qho irreversibly oxidized daim ntawv ntawm retinol los yog retinoic acid muaj qhov sib txawv heev uas yog ib qho tseem ceeb ntawm cov tshuaj hormones zoo li kev loj hlob rau epithelial thiab lwm cov hlwb. Retinol thiab lwm cov ntawv ua ntej yog metabolized hauv lub cev thiab khaws cia hauv daim siab, feem ntau yog retinyl palmitate. Vitamin A nyob rau hauv cov hlab ntsha yog hu ua serum retinol thiab raug soj ntsuam nyob rau hauv "retinol equivalents".
Y Beta Carotene yog dab tsi?
Beta-carotene yog cov xim liab-txiv kab ntxwv xim muaj zog ntau ntau hauv ntau cov nroj tsuag thiab txiv hmab txiv ntoo. Nws yog cov organic complex thiab yog tshuaj categorized li hydrocarbon thiab precisely raws li ib tug terpenoid, replicating nws derivation los ntawm isoprene units. Nws yog ib tug tetraterpene thiab ib tug khub ntawm carotene. Carotene yog synthesized biochemically los ntawm yim isoprene units thiab yog li muaj 40 carbons. Ntawm cov chav kawm tag nrho ntawm carotene, beta-carotene yog qhov paub zoo los ntawm kev muaj beta-rings ntawm ob qhov kawg ntawm cov saw ntev molecule. Beta-carotene yog nplua nuj nyob rau hauv carrots, taub dag, thiab qos yaj ywm qab zib uas ua rau lawv cov xim txiv kab ntxwv. Ntxiv rau qhov ntawd, beta-carotene yog ib qho pro-vitamin A thiab ob lub molecules ntawm retinol (pre-vitamin A) tuaj yeem raug tsim los ntawm ib qho molecule ntawm beta-carotene.
Qhov txawv ntawm Vitamin A thiab Beta Carotene yog dab tsi?
Vitamin Group:
Vitamin A yog cov vitamin fat-soluble. Nws yog ib pawg ntawm unsaturated khoom noj khoom haus organic tebchaw; uas muaj xws li retinol, retinal, retinoic acid, thiab ntau provitamin A carotenoids, thiab beta-carotene.
Beta-carotene yog provitamin A.
Chemical Structure:
Txhua hom vitamin A muaj lub nplhaib beta-ionone uas txuas nrog isoprenoid saw, hu ua pawg retinyl. Qhov no yog qhov tseem ceeb rau kev ua haujlwm vitamin.
Beta-carotene muaj ob pawg retinyl txuas.
Synthesis:
Vitamin A tsis tuaj yeem hloov mus ua beta-carotene.
Beta-carotene tuaj yeem hloov mus rau hauv vitamin A. Ib qho molecule ntawm beta-carotene tuaj yeem tsim ob lub molecules ntawm retinol. Lub enzyme beta-carotene 15, 15'-dioxygenase cleaves beta-carotene hauv plab hnyuv mucosa thiab hloov mus rau retinol. Qhov kev hloov dua siab tshiab no tsis tshua muaj vim qhov tsis zoo ntawm beta-carotene hauv cov hnyuv nruab nrab. Yog li, 12 mg ntawm beta-carotene yuav tsum tsim 1 mg ntawm retinol.
Source:
Thaum hais txog Vitamin A, Retinol feem ntau pom muaj nyob rau hauv cov khoom noj tsiaj xws li cov khoom noj khoom haus daj thiab cov rog-soluble. Nws yog nplua nuj nyob rau hauv cod siab roj, siab, mis nyuj, butter, thiab qe.
Beta-carotene ncaj qha txhawb nqa cov xim txiv kab ntxwv ntawm ntau yam txiv hmab txiv ntoo thiab zaub. Cov roj txiv maj phaub roj, nrog rau cov txiv hmab txiv ntoo daj thiab txiv kab ntxwv, xws li cantaloupe, txiv nkhaus taw, taub dag thiab papayas, thiab txiv kab ntxwv, cov zaub hauv paus xws li carrots thiab yams yog cov nplua nuj tshwj xeeb ntawm beta-carotene. Cov xim ntawm beta-carotene yog npog los ntawm chlorophyll pigments nyob rau hauv ntsuab nplooj zaub thiab noj ntsuab nplooj xws li spinach, kale, qos yaj ywm nplooj, thiab qab zib gourd nplooj. Yog li ntawd, lawv kuj yog nplua nuj nyob rau hauv beta-carotene.
Qhov tseem ceeb:
Vitamin A yog ib qho tseem ceeb rau lub zeem muag, kev saib xyuas lub cev tiv thaiv kab mob, kev loj hlob thiab kev loj hlob, kev hloov noob caj noob ces, kev loj hlob ntawm embryonic, thiab kev loj hlob, pob txha metabolism thiab kev ua haujlwm antioxidant
Beta-carotene yog siv rau hauv cov khoom noj khoom haus raws li pro-vitamin A. Nws yog ib qho muaj zog antioxidant. Tsis tas li ntawd, nws yog xim txiv kab ntxwv xim thiab siv los ua cov xim ntxiv. Nws yog tus lej E E160a.
Side Effects:
Kev noj cov vitamin A ntau dhau tuaj yeem ua rau xeev siab, petulance, txo qis qab los noj mov, ntuav, pom qhov muag tsis pom kev, ntxhov siab, plaub hau poob, mob nqaij thiab plab thiab tsis muaj zog, tsaug zog, thiab hloov lub hlwb.
Cov kev mob tshwm sim feem ntau ntawm kev noj ntau dhau ntawm β-carotene yog carotenoderma (txiv kab ntxwv tawv)
Hauv kev xaus, vitamin A thiab beta-carotene yog cov khoom noj tseem ceeb rau tib neeg lub cev. Vitamin A yog ib qho tseem ceeb roj-soluble vitamin uas yog synthesized los ntawm beta-carotene. Beta-carotene muaj ntau daim ntawv thov zaub mov, thiab nws yog pro-vitamin A.
