Acylated starch synthesis

Conventional synthesis of such materials employs fiitty-acid chlorides or anhydrides in organic solvents. Recently, a fiee-solvent method to esterify starch was developed in our laboratory using formic acid and octanoyl chloride as the gelatinizing and acylating agents respectively. After optimization of reaction conditions, starch octanoate with DS of 1.7 was obtained with a recuperation yield of 89 %. ... 

Acylation reactions of cellulose with tty acids have been accomplished in the absence of solvent with the help of a co-reagent and the solvent exchange technique as a pretreatment for cellulose. The latter included soaking of cellulose with water, followed by washing with ethanol and finally with the tty acid. In the present work, we propose a new technique for the synthesis of cellulose and starch tty esters by esterification with fatty acids without the use of co-reagent or organic solvent. This technique passes through an emulsion to accomplish an intimate contact betwe the polysaccharide and the fatty acid. 

Friedel-Crafts acylation catalyst, 95, 96 MA polymerization catalyst, 254 Stannous chloride, 460 Stannous oxalate, 480 Starch, MA condensations, 516 Steroids, MA Diels-Alder synthesis, 145 Steryl methacrylate, MA copolymerization, 528 Stilbene, cis and trans, 202 MA copolymerization, 307, 373, 374, 379, 394 MA reactivity ratios, 302 Stilbene oxide, MA photochemical addition, 197, 228... 

The present study indicates that the environmetal CO concentration affects on membrane lipids in addition to photosynthetic characteristics. Under low CO2 concentration, novo synthesis of carbonic anhydrase is induced and pyrenoid with starch sheath is developed in various eukaryotic microalgae. So far some intermediate(s) of photorespiratory pathway and/or CO2/O2 ratio has been proposed to be the initial reaction which induces the de novo synthesis of carbonic anhydrase [4,53. Carbon dioxide is much more soluble in fats than water and the adsorption is quick [63. Therefore, the changes in the degree of unsaturation of the fatty acyl chain in the membranes may be one of the initial reactions which occur in response to the decrease of CO concentration. 

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