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This article describes some of the research experiences conducted at the University of Cauca In the field of biodegradable packaging as raw material derivatives agroindustrial processing of cassava (Manihot esculenta Crantz). Headings are addressed related to the formation of human talent, strengthening research groups participate, support from government agencies such as the Ministry of Agriculture and Rural Development-MARD- Colciencias and General Royalties System, relations with other institutions Higher Education in Colombia and abroad, participation in technological development centers, producers and industry organizations with collaborative work have enabled us to consolidate and strengthen the agribusiness chain of cassava in Cauca department. It also describes the processes in terms of intellectual property such as patents and licensing obtained, which strengthen the research group "Science and Technology of Agro-Interest Biomolecules CYTBIA-" leader in the field of bioplastics, and related information required with the creation of a "Spin Off" Technological Development and Innovation in biodegradable, which validates the impact of research developments directly in Science, Technology and Innovation. [ABSTRACT FROM AUTHOR]

A bioplastic semirrigid material was developed from native flour of four cassava varieties (MBRA 383, MPER 183, CM 4574-7 and CM 7951-5), incorporating fique dust, by thermo-compression technique. The material was obtained by subjecting the raw material mixture in a mold and subsequently it was compressed at 200°C. The cassava variety suitable for use in the material development was MPER 183, with results of last tensile and flexural resistance of 1,8 MPa ± 0,2 and 3,5 ± 0,2 MPa, respectively, and resistance to impact of 21,2 ± 0,1 J/m. Compression molded samples, obtained in this work are technologically feasible and favorable performance characteristics presented as an alternative to the use of polystyrene foam food packaging applied. [ABSTRACT FROM AUTHOR]

Starch is a renewable and cheap natural polysaccharide from that is easily to make biodegradable plastic products. However, its products have low mechanical properties and tend to change its properties in the presence of water. For reduce the problems caused for water in the plastic product derived from starch, originate from de high hydrophilicity of this polymer, are diverse strategies such as the chemical modification of starch, the blend of starch with minor hydrophilic polymers and the superficial modification of the final products. In the present review is presented some examples of investigations related with the mentioned strategies, focused the attention in superficial modification that allow decrease the hydrophilicity of plastic products based on starch without affect the internal characterizes of material significantly. [ABSTRACT FROM AUTHOR]

Polyhydroxyalkanoates are natural polyesters with excellent characteristics to replace conventional plastics. They are bio-compatibles and biodegradables and in a short time they can be reduced to carbon dioxide and water. They are intracellular synthetized by different bacteria and they can be obtained from a large variety of substrates, including some agriculture wastes. The main target is to identify native strains with potential to produce polyhydroxyalkanoates. A bio-prospection was performed in the sludge of San Fernando's waste water plant (Itagüí-Antioquia). 19 colonies were isolated in a selective agar, and then the colonies with positive oxidase were selected. The activation and cultivation were carried in a liquid minimum salt medium (MSM) to establish the biopolymer accumulation rate. The strains LM-3D, LAR-4D, LAR-5B, LAR-5E exhibited a pHAs accumulation rate of 2, 10, 4, 3% respectively, and the strain LM-3F exhibited a 25% of biopolymer accumulation rate against others. Upon the biochemical analysis it was established that polymer producer strains were Shingomonas paucemobilis, Aeromonas hydrophila and Aeromonas sobria. [ABSTRACT FROM AUTHOR]

The polyhydroxyalkanoates (PHA's) intracellular granules accumulated by bacterial species in environments with imbalance in Carbon/Nitrogen, Carbon/ Phosphorus have similar physicochemical properties to conventional plastics, but are biodegradable. However, the high cost of PHA's lead to strategies of production, but with the lowest possible investment, therefore, in this study we explore different environments in Nariño department to search and selecting PHA's producing bacteria with industrial potential. The presumptive detection of PHA's bacteria isolated from soil and water samples were performed using the Nile Red dye, isolates selected were subjected to batch fermentation and the polymer obtained was characterized by gas chromatography and gas chromatography-mass spectrometry. Those isolates with increased accumulation of polymer were characterized by biochemical tests and partial sequencing of the16SrRNAgene. Finally, was evaluated the production of PHA's using as substrate domestic wastewater. 189 bacterial isolates were obtained, which produce from 0,01gL-1 to 5,24 gL-1 of homopolymer poly-3-hydroxybutyrate or poly-3-hydroxybutyrate-co-3-hydroxyvalerate. Likewise, were recovered 0,111gL-1 of Poly-3-hydroxybutyrate from wastewater. From this perspective, wild bacteria producing PHA's isolated in Department of Nariño have different potential to advance environmental and industrial processes. [ABSTRACT FROM AUTHOR]

Physicochemical properties of native and hydroxypropylation cassava (Manihot sculenta Crantz) starch varieties were studied. Starches from three cassava varieties were analyzed, codified as CM 7138-7, CUMBRE 3 and SM 707-17. The objective was to identify the changes in the physicochemical properties due to hydroxypropylation process. It was also obtained the pasting curves, thermal properties by differential scanning calorimetry (DSC) and thermogravimetry (TGA) and Fourier transform infrared spectroscopy (FT-IR). The native starches exhibited differences in the pasting curves, glass transition temperatures (Tg) and fusion temperatures (Tm). The modified starches showed differences in the molar substitution degree, pasting curves, Tg, Tm and the FT-IR spectrum. The hidroxypropylation process did generate significant changes in the properties of native starches. In both cases, this differences could be attributed to starch amylose and amylopectin content. Respect to native and modified starches differences, hidroxypropylation process generated changes over studied properties. Due to amylose content and modified starch less viscosity and Tg values, was concluded that variety CM 7138-7 was selected as the one with probably major package making potential. [ABSTRACT FROM AUTHOR]

In this work it was studied the optical properties and water vapor permeability (WVP) in biodegradable films made from two thermoplastic cassava starch varieties native and hydrolyzed, polylactic acid and polycaprolactone. The films were obtained by extrusion process, and their properties were rated for 1, 8, 60 and 120 days. The PVA for 120 days was between 2, 18 x 10-11 and 9, 12 x 10-11 g / Pa * s * m. Almost all the films retained their color issues with values of between 83,92 and 87,89 L, the parameter a * and b * were close to 0, resulting films with a slight tendency to yellow. The gloss values varied between 16,06 and 21,98 GU during the aging. This study found that aging affected significantly the optical properties and the WVP. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of different oxidation conditions by hypochlorite, on the content of carboxyl and carbonyl groups of cassava starch, finding that the concentration of oxidant had the highest effect on the formation of both groups functional. The pH had a highest effect on the content of carbonyl groups than on the content of carboxyl groups. Likewise, oxidized starch was obtained at three degrees of oxidation which exhibited lower viscosity, higher gel stability and lower retrogradation tendency when compared with native starch. Films were obtained and their mechanical and thermal properties were evaluated, finding that higher modification degree incremented stress while the strain exhibited no significant differences. Conversely, the greater modification degree, the films showed lower strain and the stress showed no significant differences. The thermal analysis showed a Tg, which is not present in native starch films, a higher Tm and a gradual decrease of ΔHm with oxidation degree increasing, which might suggest a greater miscibility and interaction between film components as well as greater stability. [ABSTRACT FROM AUTHOR]

It was evaluated the morphological surface of thermoplastic starch (TPS) obtained from three modified cassava starch varieties, plasticizer and an antimicrobial agent. The films was made by blown extrusion and extended over a slide and then was taken photomicrographs with 4x and 10x objectives. It was used High Resolution Optical Microscopy to image characterization. The technique showed the effect of plasticizer addition over the starch films microstructure, it was found some inhomogeneity; however was identified some smooth regions related to form and size of starch granule, plasticizer concentration and extrusion variables process like velocity screw and temperature profile. This research contributed to characterize microstructural properties and gave some insights about the mechanical behaviour of TPS films, needed to study and make biodegradable films. [ABSTRACT FROM AUTHOR]