A new method of poly(aspartic acid) synthesis under microwave radiation

Abstract

Streszczenie-Opisano dwie metody syntezy karbamoiloetylowanych pochodnych skrobi (CrES) obejmuj¹ce etapy degradacji (chemicznej b¹dŸ enzymatycznej pod wp³ywem α-amylazy) oraz etap reakcji addycji z akryloamidem. Zbadano wp³yw warunków degradacji enzymatycznej (biodegradacji) na rozpuszczalnooeae w wodzie CrES, lepkooeae jej roztworów wodnych, stopieñ podstawienia (DS) i ciê¿ar cz¹steczkowy. Scharakteryzowano wp³yw opisanej modyfikacji skrobi na zmiany struktury jej powierzchni. S³owa kluczowe: skrobia, karbamoiloetylowanie, stopieñ podstawienia, degradacja enzymatyczna, α-amylaza, rozpuszczalnooeae w wodzie, ciê¿ar cz¹steczkowy, struktura powierzchni. WATER-SOLUBLE CARBAMOYLETHYLATED DERIVATIVES OF POTATO STARCH. PART I. SYNTHESIS AND STRUCTURE Summary-Water-soluble starch derivatives (CrES) containing carbamoylethyl groups were synthesized using two methods. The first based on chemical degradation of native potato starch under the influence of KOH or NaOH and subsequent reaction of addition with acryloamide. The other based on carbamoylethylation of native starch in such reaction and subsequent enzymatic biodegradation of CrES obtained using α-amylase. The effects of biodegradation conditions, namely: catalyst type and concentration [Ca(OH)2, KOH], time and temperature of the process and α-amylase concentration on CrES solubility in the water and viscosity of aqueous solutions obtained (Table 1 and 6) as well as on the degree of substitution (DS, Table 2-5). The lowering of molecular weight of starch products after degradation, either chemical or enzymatic one, positively influences the solubility of CrES in water (results of MALDI-TOF measurements, Fig. 1, 2 and 6). The modification causes also the changes in the surface structure of CrES facilitating its dissolution in water (results of SEM microscopic investigations, Fig. 3 and 7). Chemical structure of CrES was confirmed by FT-IR method (Fig. 4, 5 and 8).

Effect of the red and green linearly polarized light upon polysaccharide depolimerization-repolymerization in starch granules

“…Among polysaccharides, starch attracts most attention. It is useless in a native state and has to be modified on either physical, for instance [3,4], chemical, for instance [3,5,6], and enzymatic, for instance [7], ways. Also chitosan [8,9], alginate [10] and cellulose [8] received certain attention as polysaccharides of technical value.…”

Selected novel materials from polysaccharides

“…Among over 100 natural polysaccharides available commercially, the starch, cellulose, and pectins are these most commonly utilized. A vast majority of numerous solutions offering physical [2][3][4], physicochemical [5,6], chemical [7][8][9], and enzymatic [10] modifications of starch for non-nutritive purposes, are economically non-feasible. Because of the role of polysaccharides as the major source for chemical industry in this century, there is a global call for novel technologies providing more refined methods of the utilization of polysaccharides and novel materials originating from them.…”

“…Applications of polysaccharides such as starch [11,12], cellulose [13], sawdust (cellulose + lignin) [14] are common to various biodegradable plastics in which they reside either as non-bounded or physically bounded components of those composites. Starch, the most common polysaccharide, is subjected to numerous chemical modifications [7][8][9] but, recently, also in Poland, chitin and the product of its hydrolysis -chitosan, attract an increasing attention [15,16].…”