Carboxymethyl cassava starch/polyurethane dispersion blend as surface sizing agent

Cush-cush yam (Dioscorea trifida), is a sub-utilized tropical crop, rich in starch, which grown in tropical areas. The exploitation of its starch has great potential. The objectives of this research was to modify starch isolated from dark-cush-cush yam, which grown in the Venezuelan Amazonian, and commercial cassava starch, by cross linking, in order to characterize and compare them with their native counterparts. The results showed that differences in the amylose content affected the composition, structure and functional properties of both starches. The degree of substitution (DS) was more significant in the cush-cush starch yam than that of the cassava starch, even if both were within the ranges allowed by the FDA. The granular size of cassava starch was slightly changed by modification. The rheological properties also changed, increasing the viscosity peak, breakdown, consistency and setback. Finally, that modification method conferred great stability to the starches gelatinization.

Carboxymethyl starch was prepared by reacting corn starch with sodium mono chloro acetate (SMCA) in a Brabender TSE‐20 co‐rotating twin screw extruder. The effects of the SMCA/starch ratio (theoretical degrees of substitutions 2.73, 3.62, and 4.53), aqueous ethanol/(starch + SMCA) ratio (0.13 and 0.25) and the screw configuration (0, 1, and 2 kneading blocks) on the degree of substitution (DS) and reaction efficiency were studied. A 3 × 2 factorial design with 3 levels of the starch/SMCA ratio and 2 levels of the aqueous ethanol/(starch + SMCA) ratio were used. This 3 × 2 factorial design was blocked, with the screw configuration as the blocking variable. The effects of the SMCA/starch ratio and the screw configuration were found to be significant. The carboxymethylated starches were characterized using FTIR, SEM, and XRD. The microstructure of the carboxymethylated starches, studied using SEM, revealed that the integrity of the starch granules was partially preserved at low aqueous ethanol levels when no kneading block was used. However, for all other reaction conditions either granule agglomeration or fusion was observed. XRD analysis indicated substantial loss of crystallinity in the carboxymethylated starches, irrespective of the damage to the granule structure. The highest DS and the highest reaction efficiency obtained were 1.54 and 0.42, respectively.

Pineapple leaf waste, with its high cellulose content, can serve as alternative starting material for the production of carboxymethyl cellulose (CMC). In this study, synthesis conditions of CMC from pineapple leaves via the use of microwave heating were optimized. Box-Behnken design and response surface methodology were applied to schedule the experiments and to optimize the synthesis condition, respectively. Preparation of CMC was investigated by varying three factors, namely, sodium hydroxide (NaOH) concentration, monochloroacetic acid (MCA) dose, and etherification time. The process of carboxymethylation was optimized to produce CMC with high degree of substitution (DS). Optimal condition for CMC synthesis was noted to be 50% (w/v) NaOH solution, 8 g of MCA/g cellulose, and etherification time of 16 min; such optimal condition resulted in the maximum DS of 0.78. Synthesized CMC was utilized as a thickener for liquid foods (water, orange juice, milk, and mushroom cream soup) where 2% (w/v) as-synthesized CMC increased the viscosity of the foods and changed their characteristics from thin to nectar-like liquids.

In this study the physicochemical properties of gum arabic blended with cassava starch and carboxymethyl cellulose was analyzed. The results obtained showed that blending of gum arabic with cassava starch and carboxymethyl cellulose led to increase in moisture content, pH and ash content, with moisture content and some ash content values lying within WHO/FAO standards of not more than 15% and 2-4% respectively for gums. The results also revealed that blending of gum arabic with carboxymethylcellulose led to increase in viscosity and swelling index while blending with cassava starch led to decrease in viscosity and swelling index. These results suggest that blending of gum arabic with carboxymethyl cellulose and/or cassava starch can be used as modification method to tailor the properties of gum Arabic to specific applications, and as cost cutting measure, as carboxymethyl cellulose and cassava starch are cheaper than gum arabic.

Gel electrophoresis technique is an indispensable tool in biotechnology and among other related fields for separation of nucleic acids and proteins. This study determined the potential of selected cassava and sweet potato starch in the separation of DNA as alternative to agarose gel. The sample pH, gelling temperature and time were determined by Light transmittance method proposed by Craig et al. [1] Standard electrophoresis procedure was used for the starch gel electrophoresis. The result showed that composite starch gelled within 18-21 minutes while agarose and agar-agar gelled after 12 minutes. Cassava starch blended with agar-agar gelled at a temperature of 58oC while sweet potato starch blended with agar-agar gelled between 35oC - 47oC. Agarose and agar-agar maintained 54oC and 53oC respectively. There was no significant difference (P > 0.05) in pH value of the composite starch when compared to 1% agarose gel. Unblended starch samples did not form solid gel except when blended with some amount of agar-agar or agarose powder. Cassava and sweet potato composite starch formed good gel strength at 3% (2.2 g of starch and 0.8 g of agar-agar) but solid gel at 4% (3.6 g of starch and 0.8 g of agar-agar). This study demonstrated the possibilities for agarose cost reduction by 60% when cassava starch (3.6 g) was blended with 0.4 g of agarose. The cassava composite starch (4%) separated DNA molecules comparably to that of 1% agarose. Therefore, the use of these cheaper, accessible and readily available blended starch sources is highly recommended for separation of biomolecules such as DNA.

The study aims to develop a biopolymer composite made of sugar palm fiber and cassava starch that may degrade over time and to investigate the physical and structural characteristics of biocomposite films. Sugar palm fiber (SPF) was cast into a biocomposite with cassava starch (CS) as the matrix and fructose as the plasticizer using the casting process. The thermoplastic CS composite sheet was loaded with different amounts of SPF (0%, 5%, 10%, 15%, and 20% dry starch). The addition of SPF considerably improved the physical and thermal properties. It enhanced the thickness of the material while lowering its density, water content, and biodegradability. However, there was no significant increase in the tensile properties of the composite films. The filler had been absorbed into the matrix, according to SEM micrographs. With a higher concentration of SPF, the SPF/CS films had a more heterogeneous surface. It is indeed possible that the addition of SPF changed the film characteristics of cassava starch, potentially compromising the performance of the films. Overall, the findings of this study concentrate on enlightening about biopolymer composite film and highlighting its great potential for the food packaging market.

Maize starch was reacted with monochloroacetic acid in presence of sodium hydroxide. The reaction involved is known as carboxymethylation. The latter was carried out under a variety of conditions. For every set of conditions carboxymethylation was studied with respect to the extent expressed as degree of substitution (DS) and reaction efficiency (RE). Results indicated that starch:water ratio of 1:2.5 constitutes the optimal material to liquor ratio. Increasing sodium hydroxide concentration up to 8N causes significant enhancement in DS and R. E. while higher concentrations bring about sharp decrement. DS increases as the monochloroacetic acid concentration increases; opposite trend was observed with respect to RE. Increasing duration (0.5–3 h) and temperature (60–70°C) acts in favour of both DS and RE. DS is also governed by the reaction medium. Water and organic solvents were used independently as well as in admixture of solvent/water. It was found that the highest DS is achieved with isopropyl alcohol and the least with water. The DS follows the order: isopropanol > cyclohexane > dimethyl formamide > methanol > acetone > water. Isopropanol: water mixture (80:20) constitutes the most favourable medium for the carboxymethylation reaction under the conditions used.

Flow behaviours of cellulose and carboxymethyl cellulose from grapefruit peel

Implementing sustainable practices for using agricultural waste is urgent in the face of the challenges of climate change. This study aimed to investigate the application of carboxymethyl cellulose (CMC) derived from soybean hulls as a bioinput in the seed coat of beans. CMC was obtained after bleaching the pulp, alkalizing and etherifying it varying the chloroacetic acid concentration and the reaction time. The properties of CMC were compared to those of soybean hulls and bleached pulp. The CMC with the highest degree of substitution (DS) was chosen as bioinput. In addition to the control treatment, concentrations of 1%, 2%, and 3% CMC were used for coating, and the impact on the physiological quality of seeds was evaluated. CMC proved suitable as a coating agent for seeds, with a DS of 1.56 obtained with 1.2 g chloroacetic acid per gram of bleached pulp during 192 min at 63 °C. The 2% CMC solution proved to be effective, resulting in 93%, 94%, and 43.5% of germinated seeds at 5 days, 8 days, and after accelerated aging, respectively. Seedlings reached 34.2 cm in length and a dry mass of 0.05 g. Our results indicate that soybean hulls can be successfully used in the production of CMC as a coating material, improving the physiological quality of bean seeds and contributing to more sustainable agricultural practices.

Study on synergistic effects of carboxymethyl cellulose and LIPUS for bone tissue engineering

New technologies for active food packaging that can protect and interact with the food, increasing its shelf life are currently being developed. Essential oils are active compounds that, in addition to providing antibacterial protection, can improve the functional and mechanical properties of films. This research aimed to evaluate the influence of orange (Citrus sinensis L.) essential oil (AEN) on the physical and antimicrobial properties of active films produced from cassava (Manihot esculenta) starch and alginate (AY/AG) using the plate diffusion technique. The films were formulated with different concentrations of AEN (0.0, 0.5, 1.0 and 1.5 %). Elongation at break (EB), water vapor permeability (WVP), moisture content, solubility and Luminosity (L*) decreased significantly (p < 0.05) with the addition of AEN, on the other hand, tensile strength (TS), b* value (tendency towards yellow) and opacity increased. Scanning electron microscopy (SEM) images showed a smooth, uniform appearance and continuous dispersion between cassava starch, alginate. The results obtained indicated that the incorporation of AEN presented an inhibitory effect against Escherichia coli and Staphylococcus aureus bacteria. Therefore, the films obtained have a high potential to be used in the development of antimicrobial packaging for food applications

An attempt has been made to prepare β‐cyclodextrin (CD) from cassava starch. Freshly prepared samples of cassava starch from M‐4 variety was treated with Standard cyclodextrin glycosyltransferase and the product obtained was converted to bromobenzene and chloroform chlathrates. The product was identified by non‐chromatographic spectrophotometric assay and by thermal decomposition behaviour. The bromobenzene β‐CD clathrate showed a distinct pattern of thermal degradation compared to that of both pure β‐CD as well as β‐CD chloroform chlathrates. The yield of the product isolated is approximately 10% (w/w) based on starch.

Effect of cardanol-based plasticizers on thermoplastic cassava (Manihot esculenta) starch properties

Sustainable carboxymethyl cellulose from ozonated empty fruit bunch for application as food coating additive.

Sodium carboxymethyl starch (Sodium CMS) is a modified starch prepared by two successive processes, alkalization and etherification. Alkalization will change the activated hydroxyl group of starch to more reactive alkoxide (St-O-), and then carboxymethyl group will substitute the hydroxyl group into sodium CMS. This research investigated the effect of agitation (1000 rpm of stirring and 4000 rpm of homogenization) in alkalization process to the modification of native starch into sodium CMS. Cassava and sago starches were mixed with sodium hydroxide (1.8 and 1.9 moles per mole anhydrous glucose units). The combination of NaOH and homogenizing gave the highest degrees of substitution for cassava (DS 0.73) and sago (DS 0.55) starches. The sodium CMS characteristics (paste clarity, water and oil absorption capacities, solubility, swelling power) were a function of mixing method but not on the amount of NaOH used.