| sugar & name | structure | ocurance and prep | test | comments |
| primverose =6-o-B-D-xylopyranosyl-D -glucopyranose | ||||
| maltose=malt sugar >sprouting barely 4-o-a-D-glucopyranosyl-D- glucopyranose | prep in starches & dextrins by partial hyd (1-3% sprouting barely contain maltase) >boil (for coagul) >filter >conc >crystall | ozazone ,fehling (not reduce Barfoid) | ||
| Cellobiose =4-o-B-D- glucopyranosyl -D-glucopyranose | cellulose >acetylation by AC2o ,cH2so4 >cellulose octa acetate then crystalli >then hyd to cellobiose by barium ethoxide in methanol | |||
| lactose (milk sugar) = 4-o-B-D-galactopyranosyl -D- glucopyranose | from whey (by product of cheese manufacture) >conc >decol e charcoal .cryst | sp ozasone | ||
| lactulose = 4-o-B-D-galactopyranosyl -D-fructofuranose | (semisyn dissacharide) obtained by alkaline rearrang of lactose | uses :all uses depend on fermentn in large intestine by flora to lactic acid >irritant to intestinal mucosa and low PH 1-laxative 2-ttt of salmonellosis eg typhi as low PH is not favorable to salm 3-tt of protosystemic encaphalopathy (brain) >in hepatic and renal failure >accum of amm 4-redn of the risk of intestinal & colon cancers >low PH of intestine & colon (N.B) bile acids 1ry ,in high PH >2ry >carcinogenic | ||
| Gentiobiose = 6-o-B-D-glucopyranosyl -D-glucopyranose | *not free in nature but as glycosides 1-Amygdalin in bitter almond 2-a-crosin in saffron 3-in Gentianose (trisacch) in gentian root (gentiana lutea fam gentianaceae) *** prep : gentianose >by fermentation invertase >>.act on B linkage | |||
| Melibiose = 6-o-a-D-galactopyranosyl-D- glucopyranose | not free in nature but in raffinose (gal+ glu+ fruc) *by invertase enz >melibiose + fructose | |||
| sucrose =D-glucopyranosyl-B-D-fructofuranose ******* notes : a-glucosidase >sp enz on a of glu ,, invertase >sp for B-D-fructofuranoside *acid hyd >glu +fruct | carmelized sugar :upon heating of sucrose above m.p (160) partial decomposition to brown mass (carmel) >col in sweet manufacturing *** invert sugar {inversion process} sucrose[a]=+66 >acid hyd or enz (invertase) >glu [a]=52.2+ frut [a]=-93 so invert sugar [a]=-20.4 levo | present in sugar cane (saccharum officinarum) fam graminea & sugar beet (Beta vulgaris) >Apiaceae ,umbellifeae **prep :juice of sugar cane >alk by lime water (to prevent hyd & remove many impurities) >then heating (for coagulation of impurities) >filter .conc under reduced pr >sep of sucrose crystals (RAW SUGAR) >put in soln then centrifugate >dissolution >(decol by act charcoal if necessary) >then conc under red pr **the liq left after cryst >molases w is dark syrapy liq contain % of sucrose | chemical tests 1-not reduce fehlig /no osazone 2-violet col e co(no3) in presence of xxs naoH *e resorcinol/HCl >red col *e Ca(OH)2 >salts (sucrates) ,mono ,di ,tri .. Suc trisucrates >water insol >basis for sep of sucrose from molases . Then decompose salt by co2 >caco3 + sucrose >filter | |
| sucralfate (semisyn) | ||||
| Trehalose (1,1 -a-linkage) = o-a-D-glucopyranosyl-D-glucopyranose | not present in higher plants but in algae ,yeast ,moulds *difficult to be hyd by acid but it hyd by trehalase | |||
| Raffinose o-a-D-galactopyranosyl -(1>6)- a-D-glucopyranosyl (1>2)-B-D-fructofuranose | in oil seeds as cotton seed ,soya bean prep: cotton seed >crushed >aq extn >pptn by ca(oH)2 >filter >residue> + co2 >caco3 + raffinose | trisacch | ||
| Stachyose = o-a-D-galactopyranosyl (1>6) ,…raffinose | *present in stachs tubifera (japanase artichoke) & soya bean >acid hyd >2gal +glu +fruc *and by invertase >trisacch + fruct (as it act on B linkage only) | tetrasaccharide | ||