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Biodegradable packing materials with antimicrobial properties have been a concern for years because of its positive environmental implications. The present work aimed to develop the formulation of hydroxyethyl cellulose (HEC)/wheat-starch based film in which the active compound, thymol (0.5, 1, 1.5, 2, and 2.5% w/w) were incorporated into the polymeric material. Solution casting method was used for the film preparation while thymol was incorporated prior to casting. The physical and chemical properties of the developed film were determined. SEM was found to have a smooth and homogeneous with a small amount of thymol which grows coarser with 1.5% or higher thymol content. FTIR was used to find the chemical property of the film and suggested that the carbonyl functional group was unchanged in the film, however, -OH groups increased substantially with increased amount of thymol. Thermal properties were profiled through thermogravimetric analysis and differential scanning calorimeter where the AM film containing 1.5% (w/v) of thymol shows the highest thermal stability and decomposes less in comparison to other samples. The inhibitory capability of the film was tested against a list of microbial contamination and was found to successfully inhibit the growth of selected gram positive and gram negative bacteria in a wide range of studied concentration. The mechanical properties of the films were improved by 60.3% with an optimum tensile strength at thymol concentration of 1.5% w/w. It can be concluded that the film properties are retained chemically whereas mechanical properties, strength, flexibility and function of the film are being enhanced remarkably by the incorporation of thymol.

In recent years, the potential of agricultural wastes has received increasing attention from academia and industry. The aim has been to identify strategies for the conversion of low-value wastes into new materials and other value-added products. Cellulose is a naturally abundant polymer that is readily available in various agricultural wastes. It is a linear polymer consisting of β-D-glucopyranose units (disaccharides) joined by glycosidic β-1,4 bonds. Nanoparticles can be extracted from cellulose fibers using a top-down mechanically or chemically treatment. Cellulose nanomaterials have generated significant interest due to their intrinsic properties such as large surface-to-volume ratios, high tensile strength, stiffness, and flexibility in addition to good dynamic mechanical, electrical, and thermal properties. The use of nanocellulose for reinforcement in matrices improves thermo-mechanical properties, decreases the sensitivity of polymers to water, and preserves biodegradability. The mixing of nanocellulose with polysaccharides improves mechanical properties. Nano-sized cellulose fibers possess unique physical, chemical, and morphological characteristics. Hence, nano-sized cellulose fibers are considered versatile materials for addition to polymers, and application in high gas barriers and packaging materials. Other uses include electronic devices, foods, medicine, cosmetics, and health care. This chapter focuses on the cellulose nanofibers attained from banana, pineapple and corn-based agricultural wastes.

In this research, acrylic acid based hydrogels were prepared and impregnated with magnetic nanoparticles to enhance the efficiency of the adsorption and desorption of heavy metals. Acrylic acid and itaconic acid both are short chain and possess -COOH group, therefore, they are easily copolymerized and hydrophilic in nature. The acrylic based hydrogel acts as a support to hold the magnetic nanoparticles. Hydrogels were synthesized by using acrylic acid and itaconic acid as monomers at different monomer ratios. The magnetic particles were incorporated through in situ precipitation method by immersing into 0.25 M Fe (II) and 0.5 M Fe (III) ion aqueous solutions in the molar ratio of 1:2 for metal ions loading. The swelling behaviour of the plain acylic acid hydrogel and plain acrylic acid-co-itaconic acid hydrogel that were soaked in two different water solutions such as sea water and distilled water were studied. Result shows that plain acrylic acid-co-itaconic acid hydrogel has the tendency to swell more than plain acrylic acid hydrogel. The absorption and desorption capacity of the materials were tested in 0.1 M of cobalt and lead solutions. The materials show promising results and can be used to remove pollutants from industrial effluent.

In addition to offering a host of health benefits, antimicrobial (AM) wheat-based packaging is a promising form of active food packaging with great economic and environmental potential. The main objective of this study is to develop a formulation of AM wheat-based film in which the active compound, lysozyme, is incorporated into the polymeric material. A solution casting method was used in the film preparation, and lysozyme was incorporated prior to casting. The resultant film is slightly less opaque, more translucent and whitish in appearance, implying that the AM film could retain similar property with the initial opacity value of the wheat-based film. The water uptake of wheat-film is reduced with the incorporation of lysozyme. The reduction in moisture content of AM film indicates a relationship between lysozyme and water molecules in the diffusion mechanism throughout the film matrices. This film helps to reduce the growth of E. coli and B. subtilis to 1.74 and 3.48 log CFU/mL, respectively, for an incubation of 48 h. FTIR analysis implies the consistency of the chemical composition and structure of the AM film compared to the control film, which indicates that the addition of lysozyme into the wheat-based film did not affect or alter the carbonyl function groups of the wheat-based film. The study will help the researcher to discover and understand wheat-based films for incorporating antimicrobial properties and to explore new matrices for further development.

Palm oil (olein) was blended with other edible oils for the enhancement of its market acceptability in terms of melting point depression and shelf life. The physico-chemical properties like viscosity, density, melting behavior, peroxide value (PV), saponification value (SV) and iodine value (IV) of four different binary blends with four vegetable oils were evaluated. Palm olein was found to be more stable against rancidity than the other oils. For the stability against oxidation and melting point depression the palm olein-canola (PO/CO) blend was found to be better than the others. The Differential Scanning Calorimeter (DSC) thermogram of the melting behavior of the blends traces some new polymorphs of the triglyceride. This study will help the oil producing industry to find out the most economically viable oil blends for cooking purposes, with maximum nutrition as well as desirable physico-chemical properties.Aceite de palma (oleína) fue mezclada con otros aceites comestibles para aumentar su aceptabilidad en el mercado en términos de descenso del punto de fusión y mejora de su almacenamiento. Las propiedades físico-químicas tales como viscosidad, densidad, comportamiento en la fusión, valor de peróxidos (PV), valor de saponificación (SV) e índice de yodo (IV) de cuatro diferentes mezclas binarias con cuatro aceites vegetales fueron evaluadas. La oleína de palma fue más estable frente a la rancidez que otros aceites. En la estabilidad frente la oxidación y el descenso del punto de fusión, la mezcla de oleína de palma/canola (PO/CO) fue mejor que las otras. Los termogramas del calorímetro diferencial de barrido (DSC) referidos al comportamiento de fusión de las mezclas indican algunos nuevos polimorfismos de los triglicéridos. Este estudio podría ayudar a las empresas que elaboran aceites a encontrar los aceites económicamente más viables para cocinar, con buenas propiedades nutricionales, así como con unas propiedades físico-químicas deseables.