Structure and functionality of surface-active amylose-fatty amine salt inclusion complexes.

Novel value-added starch-based materials can be produced by forming amylose inclusion complexes (AIC) with hydrophobic compounds. There is currently little research on AIC use as polymeric emulsifiers, particularly for AIC with fatty amine salt ligands. This work evaluated AIC emulsifiers by studying the structure and functionality of AIC composed of high amylose corn starch and fatty amine salts (10-18 carbons, including a mixture simulating vegetable oil composition) produced via steam jet cooking. X-ray scattering verified successful AIC formation, with peaks located near 7.0°, 12.8° and 19.9° 2θ. AIC were easily dispersed in water (80-85 °C) and remained in suspension at room temperature for weeks, unlike the uncomplexed ligands or starch. AIC were highly effective emulsifying agents, with emulsifying activity indexes of 213-229 m2g-1 at pH 5, and zeta potentials, a measure of electrostatic repulsion, as high as 43.4 mV. AIC dispersions had surface tension ranging from 24 to 41 mN/m and displayed surface-active properties superior to amylose complexes formed from fatty acid salts and competitive with common starch-based emulsifiers. These findings demonstrate that fatty amine salt AIC are effective emulsifiers that can be made from low-cost sources of fatty amine salts, such as vegetable oil derivatives.

Characterization and properties of starch-dicarboxylic acid inclusion complexes prepared by excess steam jet cooking.

A series of dicarboxylic-amylose inclusion complexes (AIC) were prepared by excess steam jet-cooking high amylose corn starch with linear C10, C12, C14, and C16 dicarboxylic acids to examine the influence of two polar head groups on complex formation. The C12, C14, and C16 dicarboxylic acid AIC were prepared in 48-63 % yields and contained 8.9-11.8 % diacid while the C10 AIC gave 30 % and contained 2.6 % diacid. These AIC had V6 helical amylose structures by XRD and complexation was further confirmed by DSC, FTIR, and TGA. SEM of the C12-C16 AIC revealed micron-sized toroidal spherulites while the C10 AIC was predominantly amorphous. DSC showed two AIC related transitions. This work provides a better understanding of the formation and physicochemical properties of these diacid AIC. Preparation by excess steam jet cooking demonstrates practical and commercial utility to prepare AIC as off-the-shelf materials for food and nonfood applications.

Physical and chemical properties of pyrolyzed biosolids for utilization in sand-based turfgrass rootzones.

Biosolids are several forms of treated sewage sludge that are intended for use as soil conditioners for horticultural, agricultural and industrial crops. The objectives of this research were to determine the chemical and physical properties of biosolids pyrolyzed at several different temperatures, and their effect on perennial ryegrass seed germination and growth. Biosolids were thermally treated in an oxygen-free (nitrogen atmosphere) retort oven at 300, 400, 500, 700 and 900 °C. As pyrolysis temperatures increased, bulk densities, total surface areas, micropore surface areas, % minerals and pH values of the pyrolyzed biosolids increased, while carbon percentage decreased compared to untreated biosolids. Fourier-transform infrared spectroscopy analysis showed decreased surface functionality as pyrolysis temperature increased. Perennial ryegrass (Lolium perenne L. 'Nui') plants were grown in mixtures of 10% (v/v) biosolids or 10% (v/v) of the various pyrolyzed biosolids and 90% coarse sand. Ryegrass plants grown in the biosolids and the 300 °C pyrolyzed biosolids mixture had the greatest shoot heights of any of the treatments after 4 weeks of growth. These results indicate that pyrolyzing biosolids at 300 °C would produce material with excellent potential as a long-term peat replacement for water and nutrient retention in sand-based rootzones.

Improved hydroxypropyl methylcellulose (HPMC) films through incorporation of amylose-sodium palmitate inclusion complexes.

Polymer film blends of hydroxypropyl methylcellulose (HPMC) and amylose-sodium palmitate inclusion complexes (Na-Palm) were produced with no plasticizer, and were observed to have improved physical and gas barrier properties as compared with pure HPMC. The crystalline amylose helices incorporating the hydrophobic sodium palmitate ligand decreased the water vapor permeability of a 50/50% blended film of HPMC/Na-Palm by 40% and decreased oxygen permeability by 96%. The incorporation of 25% Na-Palm into HPMC films resulted in improved elongation, Young's modulus and toughness. Addition of the amylose-complexes produced relatively smooth, high clarity films which had reduced solubility in neutral and acidic solutions. Increasing concentrations of Na-Palm increased film thermal resilience and increased storage modulus at high temperatures. The heat deflection temperature of the films also increased with increasing concentrations of amylose-complex; HPMC/Na-Palm film blends with >50% Na-Palm displayed almost no material deformation up to 250 °C.

Effect of spray drying on the properties of amylose-hexadecylammonium chloride inclusion complexes.

Water soluble amylose-hexadecyl ammonium chloride complexes were prepared from high amylose corn starch and hexadecyl ammonium chloride by excess steam jet cooking. Amylose inclusion complexes were spray dried to determine the viability of spray drying as a production method. The variables tested in the spray drying process were the% solids of the amylose-hexadecyl ammonium chloride complex being fed into the spray dryer, feed rate and the spray dryer outlet temperature. The amylose-inclusion complexes remained intact in all spray drying conditions tested as determined by X-ray diffraction. The rheological properties of solutions of the spray dried amylose-complexes remained unchanged when compared with the freeze dried control. Particle density and moisture content decreased with increased outlet temperature while particle size increased. X-ray diffraction and DSC analysis confirmed the formation of type II amylose inclusion complexes. Spray drying is a high throughput, low cost continuous commercial production method, which when coupled with excess steam jet cooking allows for the industrial scale production of cationic amylose-hexadecyl ammonium chloride complexes which may have value as flocculating and filtration enhancing agents and other aspects of paper production.

A one-pot synthesis of 1,6,9,13-tetraoxadispiro(4.2.4.2)tetradecane by hydrodeoxygenation of xylose using a palladium catalyst.

In an effort to expand the number of biobased chemicals available from sugars, xylose has been converted to 1,6,9,13-tetraoxadispiro(4.2.4.2)tetradecane in a one-pot reaction using palladium supported on silica-alumina as the catalyst. The title compound is produced in 35-40% yield under 7 MPa H2 pressure at 733 K using 3-10 wt%Pd on silica-alumina catalyst. It is isolated using a combination of liquid-liquid extractions and flash chromatography. This dimer can be converted to its monomer, 2-hydroxy-(2-hydroxymethyl)tetrahydrofuran, which ring opens under acid conditions to 1,5-dihydroxy-2-pentanone. This diol can then be esterified with vinylacetate in phosphate buffer to produce 1,5-bis(acetyloxy)-2-pentanone which is an inhibitor of mammalian 11ß-hydroxysteroid dehydrogenase 1. (1)H and (13)C nmr spectra of each of these species are reported. The single crystal X-ray structure of the title compound is also reported. These data were collected in a temperature range of 100 K-273 K and show a solid state phase change from triclinic to monoclinic between 175 K and 220 K without a conformational change.