Phytosterols, uas encompass cog sterols thiab stanols, yog steroid tebchaw zoo xws li cov roj uas tshwm sim ntawm cov nroj tsuag thiab txawv xwb hauv cov sab chains thiab/los yog kuaj pom los yog tsis muaj ob nyiaj. Stanols muaj saturated sterols, tsis muaj ob bonds muaj nyob hauv lub sterol nplhaib qauv. Sterols ntau tshaj li ntawm 200 thiab lwm yam cajmeem tebchaw muaj tau qhia. Dawb muab rho tawm los ntawm roj phytosterols cov insoluble hauv dej, insoluble kuj nyob rau hauv roj, thiab hauv cov cawv suab thaj uas soluble.
Phytosterol-enriched zaub mov thiab noj tshuaj pab tau tau marketed xyoo lawm. Txawm zoo yav LDL roj uas txhaws taus tej teebmeem, tsis ncav proven tseeb ntawm tej kev lig ntxim rau cov kab mob (CVD) los yog cov seem tuag tshwm sim.
Qauv
Lub molecule nyob ntawd lub tsheb es yog β-sitosterol. Nomenclature rau steroid cev pob txha yog nyob sab xis.
Yog tias tshem cov pa roj carbon 242, campesterol yuav tau txais.
Yog tias tshem cov carbons 241 thiab 242, roj yog tau.
Tshem tawm ib hydrogen ntawm carbons 22 thiab 23 yields stigmasterol (stigmasta-5,22-dien-3β-ol).
Los hydrogenating cov nyiaj muab ob npaug rau ntawm carbons 5 thiab 6, β-sitostanol puas tau.
Hydrogenating cov nyiaj muab ob npaug rau ntawm carbons 5 thiab 6 thiab tshem cov 241, campestanol yuav tau txais.
Tshem cov 242 thiab hydrogens ntawm carbons 22 thiab 23, thiab inverting tus stereochemistry nyob C-24 yields brassicasterol (ergosta-5,22-dien-3β-ol).
Tshem tawm ntxiv ntawm hydrogens los carbons 7 thiab 8 ntawm brassicasterol yields ergosterol (ergosta-5,7,22-trien-3β-ol). Tseem ceeb: Ergosterol no tsis yog ib tug tsob nroj sterol. Ergosterol yog ib yam ntawm tes Week, liab lub muaj nuj nqi tib hauv yog ho nphav kiag roj pab raws li nyob rau hauv lub hlwb tsiaj tivthaiv.
Esterification ntawm pawg hydroxyl rau cov 3 fatty/organic acids uas yog los yog carbohydrates tau rau tsob nroj sterol esters, xws li oleates, ferulates thiab (ua) glycosides.
Kev noj haus phytosterols
Tus richest lawm tias nws tshwm sim los ntawm phytosterols cov zaub roj thiab cov khoom uas ua los ntawm lawv. Lawv yuav muaj nyob hauv tsab ntawv dawb thiab ua cov kua qaub fatty acid/cinnamic esters los ua glycosides, feem. Daim ntawv bound yog feem ntau hydrolyzed nyob rau hauv cov hnyuv me los ntawm cov enzymes pancreatic. Ceev, uas muaj ntau nyob rau hauv phytosterols, feem ntau tus noj nyob ob peb hnub lawm mas, tiam sis yeej tseem ho ua tau kom tag nrho phytosterol kom tsawg. Khoom cereal, zaub, txiv hmab txiv ntoo thiab thiab, uas yuav tsis kom nplua nuj nyob hauv phytosterols, yuav hais tau teeb meem loj los ntawm phytosterols vim nws yooj yim dua intakes. Qhov kom tsawg ntawm lawm zom zaws phytosterols yog hom twg ntawm ~ 150 – 450 mg/nruab hnub nyob ze nrog nws noj mov tsis tau. Qho kev tsim los neeg tsis noj nqaij seb puas yog noj tej cov zaubmov muaj lawm ua yielding upwards of 700 mg/hnub. Qhov ntau tab sis phytosterols nyob rau hauv cov neeg noj cov β-sitosterol, campesterol thiab stigmasterol, yam nyiaj rau txog 65%, 30% thiab 3% ntawm noj txheem, feem. Tshaj stanols cog nyob hauv cov neeg noj cov sitostanol thiab campestanol, uas txiav tsim mus txog li 5% ntawm kev noj haus phytosterol.
Kev thov
EFSA
Rau lwm cov zaub mov kev ruaj ntseg cai (EFSA) xaus lus tias tsua yuav txo tau thaj tsam li ntawm 7 mus rau 10.5% yog ib tug neeg kov 1.5 2.4 grams cog sterols thiab stanols txhua txhua hnub. Cov pom tias cov nyhuv yog feem ntau raws txoj cai nyob rau hauv cov thawj 2-3 lub lis piam. Longer-term tshawb extending nyob 85 lub lim piam tas mas pom tias nyhuv uas muaj roj uas txhaws taus tej qhov yuav ua li cas. Nyob rau qhov no thiab lwm yam ntaub ntawv miv nyuas siv zug lub EFSA zaum xav txog cov hauv qab no kev thov kom muaj kev cuam tshuam cov muaj kev paub: "cog sterols pom tias tsawg dua/txo qhov tsua. Ntshav roj uas txhaws taus tej zaum tau kom tsis txhob mob plawv coronary"thiab"cog stanol esters pom tias tsawg dua/txo qhov tsua. Ntshav roj uas txhaws taus tej zaum tau kom tsis txhob mob plawv coronary".
FDA
(FDA) tau tso cai cov lus hauv qab no daim ntawv thov nyiaj phytosterols: kev cog sterol esters: khoom noj uas muaj tsawg kawg yog 0.65 g ib qho ntawm tsob nroj sterol esters, noj tsis tas ib hnub ob zaug nrog rau zaub mov noj rau lub sij hawm tag nrho kom tsawg ntawm tsawg 1.3 g, yog txoj kev noj cov zaub mov uas tsis muaj saturated roj thiab, yuav tau kom tsis txhob mob plawv. Ib qho ntawm [npe zaub mov] khoom siv cov roj zaub sterol esters ___grams. Kev cog stanol esters: khoom noj uas muaj tsawg 1.7 g ib qho ntawm tsob nroj stanol esters, noj tsis tas ib hnub ob zaug nrog rau zaub mov noj rau ib tug tag nrho txhua hnub kom tsawg ntawm tsawg 3.4 g, yog txoj kev noj cov zaub mov uas tsis muaj saturated roj thiab, yuav tau kom tsis txhob mob plawv. Ib qho ntawm [npe zaub mov] khoom siv ntawm tsob nroj stanol esters ___grams. Ntawm FDA tam sim no yog muab tus neeg pab leg ntaubntawv huv rau phytosterols. Thaum muab tej hlw kom qis uas muaj phytosterol supplementation, tus FDA xaus lus tias thaum noj ntau yam rau ntawm 1 mus rau 3 grams hauv tej khoom noj enriched, phytosterols no ua rau cov lus tseem ceeb (5-15%) tawm txiav nyob hauv cov ntshav LDL roj uas ntu placebo. (FDA) tau xaus lus tias tus niaj hnub noj kom tsawg ntawm 2 grams lub zog phytosterols (expressed li tsis-esterified phytosterols) no yuav tsum muab kom tau ib qho kev tso cai thov relating phytosterol noj rau tej roj thiab CVD tej yam ntshai.