Ib tug betaine (BEET-uh-een, bē'tə-ēn', -ĭn) nyob rau hauv chemistry yog ib qho tshuaj nruab nrab nruab nrab nrog cov pab pawg ua haujlwm zoo cationic xws li quaternary ammonium lossis phosphonium cation (feem ntau: onium ions) uas tsis muaj hydrogen atom thiab nrog ib pab pawg neeg ua haujlwm tsis zoo xws li pawg carboxylate uas yuav tsis nyob ib sab ntawm qhov chaw cationic. Ib tug betaine li no tej zaum yuav yog ib hom zwitterion. Keeb kwm lub sij hawm tau tseg rau trimethylglycine nkaus xwb. Nws yog siv los ua tshuaj ib yam nkaus.Hauv cov kab mob lom neeg, ntau yam tshwm sim ntawm betaines ua cov organic osmolytes, cov khoom tsim los ntawm ib puag ncig los ntawm cov hlwb los tiv thaiv kev ntxhov siab osmotic, drought, salinity lossis kub kub. Intracellular tsub zuj zuj ntawm betaines, tsis cuam tshuam rau kev ua haujlwm enzyme, cov qauv protein thiab kev ncaj ncees ntawm daim nyias nyias, tso cai rau cov dej tuav hauv cov hlwb, yog li tiv thaiv los ntawm cov teebmeem ntawm lub cev qhuav dej. Nws kuj yog ib qho methyl pub dawb ntawm kev paub txog qhov tseem ceeb hauv biology.Betaine yog alkaloid nrog muaj zog hygroscopicity, yog li nws feem ntau kho nrog cov tshuaj tiv thaiv kab mob hauv cov txheej txheem ntau lawm. Nws cov qauv molecular thiab daim ntawv thov cov nyhuv tsis txawv txawv ntawm ntuj betaine, thiab nws belongs rau lub ntuj tshuaj sib npaug ntawm cov tshuaj synthesis.Betaine yog ib qho zoo heev methyl pub dawb uas tuaj yeem hloov methionine thiab choline. Hloov methionine los txhim kho kev tsim khoom thiab txo tus nqi pub.