IsiNcithelo

IsiNcithelo, noma ushukela wezithelo, ushukela olula we-ketonic olutholakala ezitshalweni eziningi, lapho uvame ukuhlanganiswa nesiNcishuko ukwakha i-sucrose yesiNcithimbili. Ingenye yeziNcithinye amathathu okudla, kanye ne-glucose ne-galactose, efakwa ngqo egazini ngesikhathi sokugaya. UFructose watholakala ngusokhemisi waseFrance u-Augustin-Pierre Dubrunfaut ngo-1847. Igama elithi "fructose" laqanjwa ngo-1857 usokhemisi waseNgilandi uWilliam Allen Miller. I-fructose emsulwa, eyomile iqinile, imhlophe, ayinaphunga, i-crystalline solid, futhi iyincibilikisi enamanzi kakhulu kunabo bonke ushukela.I-Fructose itholakala kuzithelo zezinyosi, izihlahla nezomvini, izimbali, amajikijolo kanye nemifino eminingi yezimpande.

Isakhiwo se-Fructose(amakhemikhali)

I-Fructose iyi-6-carbon polyhydroxyketone.Crystalline fructose isebenzisa isakhiwo esinamalungu ayisithupha se-cyclic, esibizwa nge-β-d-fructopyranose, ngenxa yokuzinza kwe-hemiketal ne-hydrogen-bonding yangaphakathi. Kwisixazululo, i-fructose ikhona njengenhlanganisela yokulingana kwe-tautomers β-d-fructopyranose, β-d-fructofuranose, α-d-fructofuranose, α-d-fructopyranose ne-keto-d-fructose (ifomu elingeyona i-cyclic).

Ukusatshalaliswa kwama-d-fructose tautomers esixazululweni kuhlobene nokuhlukahluka okuningana, okufana ne-solvent kanye ne-temperature.d-Fructopyranose kanye ne-d-fructofuranose ukusatshalaliswa emanzini kukhonjwe kaningi njenge-70% ye-fructopyranose ne-22% ye-fructofuranose.