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This study aims to investigation of the guar gum-manganese dioxide (GG/MnO₂) nanocomposite (NC) synthesized using an environment-friendly method and the degradation of reactive yellow (RY 145) dye in the UV system.

Characterization of the GG/MnO₂ NCs were conducted using field emission scanning electron microscopy, X-ray diffraction and Fourier-transform infrared spectroscopy. Experiments were conducted using a 1 L glass reactor coupled with Ultraviolet (UV-C) blue light bulb of wavelength 250 nm and power of 8 W.

The NC (2.25 g/L) displayed high RY 145 dye degradation (81%) with 10 mg/L of concentration at pH 3. The coefficient of determination (R² 0.99) also depicted that the model fits the experimental data. The analysis of variance (ANOVA) showed that the F-values of 464.75, 276.04 and 5.15 are related to the dose of GG/MnO₂ NCs, initial concentration of RY 145 dye and solution pH, respectively.

The GG/MnO₂ NCs followed by photo oxidation process (UV-process) could be used to degrade the RY 145 dye from synthetic wastewater.

There are two main innovations. One is that the novel process is performed successfully for RY 145 dye degradation. The other is that the optimized conditions are obtained by Box–Behnken design. Also, the effects of different variables on the RY 145 dye removal efficiency were investigated.

The purpose of this study is to modify guar gum (GG) into guar gum acetate (GGA) and phthaloyl guar gum (PHGG) by transesterification and phthaloylation, respectively.

GG has been modified into GGA through transesterification reaction between GG and vinyl acetate and PHGG through esterification reaction with phthalic anhydride. The modified GG was characterized by solubility test, Fourier-transform infra-red (FTIR) spectroscopy, proton nuclear magnetic resonance (¹H NMR) spectroscopy, X-ray diffractometry (XRD) and thermogravimetric analysis. Swelling properties of GGA and PHGG hydrogels in water were evaluated.

These two types of modified GG have better solubility such as in dimethyl sulfoxide and N,N-dimethylformamide but no true organosolubility was achieved. The modifications were confirmed through FTIR with new absorption peaks at 1,733 cm⁻¹ for GGA and 1,709 cm⁻¹ for PHGG coupled with observed substitution peaks at 1.80 to 2.20 ppm and 7.40 to 7.90 ppm, respectively, from ¹H NMR spectroscopies. XRD revealed both GGA and PHGG are less crystalline than native GG. GGA was found to be more thermally stable than native GG, whereas PHGG was slightly less thermally stable than native GG. The swelling property in distilled water for native GG, PHGG and GGA was 918.43 ± 46.62%, 537.04 ± 2.87% and 393.04 ± 13.42%, respectively.

The GGA and PHGG hydrogels are expected to be useful for biomedical fields such as tissue engineering and drug-delivery.

Modifications of native GG into GGA using vinyl acetate and PHGG using phthalic anhydride are novel.

Nowadays, application of biopolymers on geotechnical engineering works is booming to avoid the harsh effects on environment by using conventional methods for soil treatment. In this present study, xanthan gum (XG) is used as a biopolymer to improve dispersive properties of the soils because these soils are easily prone to erosion, which may lead to the damage of many hydraulic structures.

In the present study, attempts are made to reduce the dispersive potential and increase the Strength and erosion resistance by treating the soils with various percentages of XG (0.5%, 1%, 1.5% and 2%). To assess the dispersive potential and erosion resistance of soils, tests such as double hydrometer test, pinhole erosion test, crumb test and cylinder dispersion test were conducted. Further tests were expanded for its geotechnical characteristics such as Atterberg’s limits, standard proctor test, unconfined compressive strength test, one-dimensional consolidation for various curing days. Scanning electron microscopy analysis was also carried out to know the microscopic view towards its particle orientation and bindings. Chemical tests such as sodium absorption ratio, total dissolved solids (TDS) and percentage sodium (PS), electronic conductivity and pH tests were also conducted.

The results revealed that there is a reduction in the dispersive potential of XG treated soils for all the combinations. Addition of XG decreased the PS in the soil as a result dispersivity of soil decreased. Strength and erosion resistance of soil increased with the addition of XG and 1% XG was observed to be the optimum percentage for stabilizing these types of soils.

These results will be very much helpful for engineers when they come across with dispersive soils for better handling and management.

The originality of this study was an attempt towards sustainable development by treating dispersive soils with XG and effects on various geotechnical and dispersive characterizes.

The purpose of this paper is to apply okara flour in the elaboration of a product, verifying the effect of the fermentation by Lactobacillus plantarum BG 112 on the antihypertensive activity and to develop probiotic sauce with gums and low lipid content.

During the fermentation process, the inhibitory activity of angiotensin-converting enzyme (ACE) and production of organic acids were determined. The simplex-centroid mixture of guar gum, xanthan gum and pregelatinized cassava starch was used for studying the variables water holding capacity, viscosity and firmness. Counts of probiotics and in vitro survival of probiotics in simulated gastrointestinal conditions were made.

The fermented soymilk showed ACE inhibition capacity above 50 percent with 32 h of fermentation, increasing the levels of lactic acid and acetic acid progressively. Based on the regression analysis and response surfaces, the binary mixture with guar gum and xanthan was chosen as the most suitable for the formulation of the sauce, having over 30 days of storage counts above 8.5 log CFU.g⁻¹ and above 6 log CFU.g⁻¹ after simulation of gastrointestinal conditions. The global acceptance was 7.0 corresponding to the moderately liked.

The findings suggest that the sauce developed has been well accepted by potential consumers and can be incorporated into the diet and can result in health benefits for the consumer when regularly ingested. The fermentation process of soymilk promoted an increase in antihypertensive capacity. Despite the reduction in viable cell counts throughout storage, counts remained high in the product, having a high survival rate after exposure under simulated gastrointestinal conditions.

The use of okara flour in the diet is viable and helps to improve the nutritional composition of foods. The use of okara flour in sauce showed potential applicability and could be incorporated into different products. The fermentation process of soymilk with okara flour produces benefits beyond the sensorial characteristics. The elaborated probiotic sauce presented physical–chemical and microbiological stability throughout the storage, being an alternative for people with food restrictions.

The purpose of this paper is to present an overview of functional properties of the polysaccharide-based component and their application in developing edible film and coating for the food processing sector.

In this review study, approximately 271 research and review articles focusing on studies related to polysaccharide-based components and their film-forming properties. This article also focused on the application of polysaccharide-based edible film in the food sector.

From the literature reviewed, polysaccharide components and components-based edible film/coating is the biodegradable and eco-friendly packaging of the materials and directly consumed by the consumer with food. It has been reported that the polysaccharide components have excellent properties such as being nontoxic, antioxidant, antimicrobial, antifungal and with good nutrients. The polysaccharide-based edible film has lipid and gas barrier properties with excellent transparency and mechanical strength. In various studies, researchers worked on the development of polysaccharide-based edible film and coating by incorporating plant based natural antioxidants. This was primarily done for obtaining improved physical and chemical properties of the edible film and coating. In future, the technology of developing polysaccharide-based edible film and coating could be used for extending the shelf life and preserving the quality of fruits and vegetables at a commercial level. There is more need to understand the role of edible packaging and sustainability in the food and environment sector.

Through this review paper, possible applications of polysaccharide-based components and their function property in the formation of the edible film and their effect on fruits, vegetables and other food products are discussed after detailed studies of literature from thesis and journal article.

The purpose of this study is to determine the physicochemical and rheological parameters of Albizia lebbeck gum.

Physicochemical analysis was carried out using recommended methods. Gas chromatography mass spectrophotometer and Fourier transformed infra red (FTIR) analyses were carried out using their respective spectrophotometer. Scanning electron microscopy was carried out using scanning electron microscope, while rheological measurements were carried out using Ubbelohde capillary viscometer, digital Brookfield DV 1 viscometer and a rheometer.

Albizia zygia gum is an ionic gum with unique physical and chemical properties. Scanning electron micrograph revealed that the internal structure of the gum is porous with irregular molecular arrangement. Thermodynamic parameters of viscous flow indicated the existence of few inter- and intra-molecular interactions, and the attainment of transition state was linked to bond breaking. Coil overlap transition studies revealed the existence of dilute and concentrated regimes. The viscosity of the gum was also found to decrease with decrease in the charge of cation (such that Al3+ > Ca2+ > K+) and with increase in ionic strength.

The paper provided information on physicochemical and rheological characteristics/behaviour of Albizia zygia gum, of Nigerian origin. From this information, possible application of this gum in the food and pharmaceutical industries can be deduced.

The paper is original since information concerning Albizia zygia gum of Nigerian origin are not well documented as established in the work. It also adds values on the use of Albizia zygia gum, either on its own or in combination with other gums for industrial purpose.

The purpose of this study is to investigate the authors' previously prepared and fully characterized poly (methacrylamide)-chitosan nanoparticles (CNPs) graft copolymer having 50.2% graft yield with respect to flocculation efficiency for ferric laurate aqueous dispersions. This was done to compare the ability of the latter cheap, biodegradable and ecofriendly hybrid natural-synthetic polymeric substrate as a flocculant in comparison with higher cost, nonbiodegradable and harmful polyacrylamide as a well-known synthetic flocculant counterpart.

The graft copolymerization process was carried out at 450°Cfor 120 min using (1.0 g) CNPs, methacrylamide (1.5 g), 100 mmol/l potassium chromate and 80 mmol/l mandelic acid. Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis and specific viscosity were used to characterize and analyze the resultant copolymer. The flocculation efficiency was conferred in terms of transmittance % and weight removal %. The main factors influencing the flocculation process, such as flocculent dose, flocculation medium pH, stirring speed, flocculation temperature and grafting extent, were comprehensively discussed.

The flocculation efficiency of the prepared copolymers revealed the following findings: increased by increasing the flocculant dose, pH, temperature and stirring speed to a maximum values denoted at 30 ppm, 6.0, 30°C and 50 r/min, respectively, then decreased thereafter; increased by increasing the extent of grafting within the range studied; showed a comparable flocculation efficiency in comparison with polyacrylamide as a synthetic polymeric flocculent; and, finally, a preliminary bridging mechanism representing the attraction between the anionic suspended particles ferric laurate and cationic poly (MAam)-CNPs graft copolymer has been projected.

The advancement addressed here is undertaken with using the authors’ poly (MAam)-CNPs graft copolymers having different extent of grafting (a point which is not cited in the literature especially for the authors’ prepared copolymer) as a hybrid natural-synthetic polymeric substrate as a flocculant for ferric laurate aqueous dispersions in comparison with the high cost and nondegradable polyacrylamide synthetic flocculant.

The purpose of this paper is to evaluate the influence of a mixture of nutrient solution, bacteria and biofilm on the consolidation, unconfined compression and desiccation characteristics of two soils that could be used in waste containment applications.

Experimental work was conducted to investigate the influence of biofilm on the desiccation, strength and consolidation characteristics of two barrier soils. The soils were evaluated with water alone and with a biofilm solution composed of nutrients, bacteria and exopolymeric substances (EPS). These solutions were mixed with a locally available clay (“red bull tallow” (RBT)) as well as a mix of 65 percent sand and 35 percent bentonite (65‐35 Mix).

Reductions in strength and increases in ductility are observed with biofilm amendment for two soil types. The shear strength was reduced from 413 to 313 kPa and from 198 to 179 kPa for RBT and 65‐35 Mix, respectively. Desiccation tests reveal an increase in moisture retention for early time increments in amended specimens, while both increases and decreases are noted after extended drying. Increases in the rate of consolidation and modest decreases in the compression and swell index were observed. In particular, the consolidation coefficient was increased from 0.036 to 0.064 cm²/min and from 0.060 to 0.093 cm²/min for RBT and 65‐35 Mix, respectively.

These results are useful in establishing the broader impacts of using biofilm as an additive to increase the performance (e.g. reduce hydraulic conductivity and increase resistance to crack formation) of barrier materials in waste containment applications. Moreover, the data provide insight into the geotechnical implications of biofilm‐producing methanotrophic activity that occurs naturally in the covers of municipal solid waste landfills.

Very little research has been published on the influence of biofilm on the behavior of barrier materials in general, and on geotechnical properties in particular. This paper is unique in making the connection between methanotrophic activity, soil modification and barrier material performance.

The purpose of this paper is to prepare alginate‐pectin‐starch containing matrices expanded by the generation of carbon dioxide, from carbonates when in contact with acids, characterise their structure in vitro and to assess their capacity to provide satiety in vivo.

For in vitro characterisation, carbon dioxide expanded polysaccharide matrices (rafts) were prepared in HCl and their structural strength was measured in terms of their capacity to resist breakage in a model test system. For in vivo trials, 12 healthy volunteers (mixed sex, aged 25‐55) were recruited to take part in the three‐part trial. Each part lasted for one week where volunteers consumed polysaccharides (in 50 ml water) with or without rafting salts (carbonates), or water (as a control). Effects on satiety, reduction of food intake and any change to body weight were evaluated with the volunteers.

The in vitro results showed that aqueous solution/dispersions (50 ml) of alginate‐pectin‐starch matrices produced rafts in hydrochloric acid (pH < 2), where increasing the ratio of carbonates to polysaccharides (range from 0.25:1 to 1.5:1, w/w) provided increased floatation capability but reducing gel strength. These rafts were stable for over 24 h at room temperature within 0.05‐0.5 M HCl. For in vivo “satiety” studies, when volunteers consumed (daily) aliquots of the polysaccharide mixture plus flavour and sweetener without carbonates 2.5 h after lunch, they felt the onset of hunger on average 186 ± 68 min after consumption of the polysaccharides. This was not significantly different from a water only control (onset of hunger at 165 ± 47 min). When polysaccharides plus flavour sweetener and carbonates were consumed, however, volunteers reported feeling the onset of hunger at 224 ± 62 min on average after consumption which was significantly different from the water control (p < 0.001), or the polysaccharides without carbonates (p < 0.01). When consuming the polysaccharide rafting format, half of the volunteers reported a reduction in size of their evening meal.

These data indicate that the alginate‐pectin‐starch combination with carbonate salts in a “gastric rafting format” provide a potential approach in the management of body weight and obesity.

This review discusses the concept of edible nanocoatings (ENCs), the biomaterials used in the coating matrices, techniques of coating development, applications, challenges and safety regulations associated with nanotechnology in food products. These ENCs are capable of imparting increased shelf life, improved appearance, better physiological qualities and bioactive potentials such as antimicrobial and antioxidant properties. ENCs can be developed using the layer-by-layer method which forms multiple alternative layers adhered together primarily by electrostatic interactions.

Various keywords such as edible coatings (ECs), safety aspects and nanocoatings were used to search the literature from Google Scholar, Research Gate, ScienceDirect, Springer Link, Taylor and Francis and PubMed. After searching enough literature, 113 articles and research papers were examined, which provides the updated overview of different aspects of edible nano-coatings.

Consumers today are very much aware of the food quality and its safety. They demand food products with longer shelf life, which are minimally processed with natural or no preservatives. ECs based on biopolymers is an alternative technique, which is biodegradable and can be consumed as such without posing any safety risks. The emergence of nanotechnology in food processing has provided new insights to develop ECs at the nanoscale with improved mechanical and barrier properties

ECs are beneficial to consumers and to the environment. ECs have generated significant attention over years as an alternative to fossil-based plastics, considering their renewable and biodegradable features