Cellulose acetate from lignocellulosic residues: An eco-friendly approach based on a hydrothermal process.

The objective of this study was to produce cellulose acetate (CA) from oat (OH) and soybean (SH) hulls through an eco-friendly solvent-and catalyst-free hydrothermal process, and also to compare the acetylation of cellulose by the conventional synthesis process, employing sulfuric acid as the catalyst, and acetic acid as solvent. Cellulose was extracted from OH and SH using a one-step chlorine-free process, resulting in materials with 86 and 81 % cellulose, respectively. CA samples obtained by hydrothermal process had degrees of substitution ranging from 0.

Perspectives on the Use of Biopolymeric Matrices as Carriers for Plant-Growth Promoting Bacteria in Agricultural Systems.

The subject of this review is to discuss some aspects related to the use of biopolymeric matrices as carriers for plant-growth promoting bacteria (PGPB) in agricultural systems as a possible technological solution for the establishment of agricultural production practices that result in fewer adverse impacts on the environment, reporting some promising and interesting results on the topic. Results from the encapsulation of different PGPB on alginate, starch, chitosan, and gelatin matrices are discussed, systematizing some advances made in this area of knowledge in recent years. Encapsulation of these bacteria has been shown to be an effective method for protecting them from unsuitable environments, and these new products that can act as biofertilizers and biopesticides play an important role in the establishment of a sustainable and modern agriculture.

Hydrogels based on gelatin, xanthan gum, and cellulose obtained by reactive extrusion and thermopressing processes.

Polysaccharides and proteins are compatible macromolecules that can be used to obtain biopolymeric hydrogels through physical interactions. In this study, an environmentally friendly strategy is being proposed to produce gelatin-xanthan gum- cellulose hydrogels, without the addition of chemical synthetic crosslinkers. Xanthan gum was employed as an alternative crosslinking agent, and cellulose was used as a potential reinforcing agent in the polymeric matrix.

Development of biopolymeric films with addition of vitamin C and catuaba extract as natural antioxidants.

Sustainability has been an important issue in cosmetic industry, resulting in increasing concerns about environmental impacts, starting by the selection of raw materials. The aim of this work was the production of biopolymeric films based on a cassava starch and gelatin mixture (1:1) with the incorporation of natural antioxidants, such as vitamin C and catuaba extract aiming its future use as an eco-friendly cosmetic. Films were produced by casting (2.

Valorization of orange bagasse through one-step physical and chemical combined processes to obtain a cellulose-rich material.

Background: Orange bagasse (OB) is an agroindustrial residue of great economic importance that has been little explored for the extraction of cellulose. The present study aimed to investigate different combinations of chemical (sodium hydroxide, peracetic acid and alkaline peroxide) and physical (autoclaving and ultrasonication) treatments performed in one-step processes for cellulose extraction from OB and to characterize the materials obtained according to their composition, morphology, crystallinity and thermal stability.

Results: The processing yields ranged from 140 to 820 g kg , with a recovery of 720-1000 g kg of the original cellulose.

Pretreatment Efficiency Using Autoclave High-Pressure Steam and Ultrasonication in Sugar Production from Liquid Hydrolysates and Access to the Residual Solid Fractions of Wheat Bran and Oat Hulls.

The objective of this study was to evaluate the combination of physical and chemical pretreatments of wheat bran (WB) and oat hulls (OH) to obtain fermentable sugars and a residual solid fraction with increased susceptibility to enzymatic hydrolysis. High-pressure steam in an autoclave and ultrasonication were employed as pretreatments, and for both processes, WB and OH were treated with sulfuric acid (HSO), neutral medium (HO) and sodium hydroxide (NaOH). Autoclave high-pressure steam in an acid medium was the most effective for the release of sugars (total sugars, xylose and glucose) from liquid hydrolysates and for the modification of the residual solid fraction.

Simple ultrasound method to obtain starch micro- and nanoparticles from cassava, corn and yam starches.

Starch nanoparticles (SNP) were produced employing a simple ultrasound method without chemical additives from cassava, corn, and yam starches, which contain 18%, 25% and 30% amylose, respectively. Simultaneously, starch microparticles (SMP) were also obtained, which were significantly smaller than the native starch granules. The yield of the process for all starch sources was 12 ± 1% SNP and 88 ± 5% SMP, starting with aqueous starch suspensions at 10% and 30 min of sonication.

Development of biodegradable coatings for maize seeds and their application for Azospirillum brasilense immobilization.

The objective of this study was to develop biodegradable coatings for agriculture crop seeds based on starch, gelatin, and polyvinyl alcohol (PVA). Developed materials were characterized according to their microstructures, barrier properties, influence on germination of maize seeds, and ability to sustain Azospirillum brasilense Ab-V5 viability in coated maize seeds. The coatings were obtained employing different proportions of starch, gelatin, and PVA, ranging from 0 to 3.

Edible films based on cassava starch and fructooligosaccharides produced by Bacillus subtilis natto CCT 7712.

The objectives of this work were to produce fructooligosaccharides (FOSs) by using the microorganism Bacillus subtilis natto CCT 7712 and to employ these FOSs as a functional ingredient in cassava starch edible films, which were characterized according to their microstructure, mechanical and barrier properties. The produced FOSs could be easily dissolved, resulting in homogeneous filmogenic solutions, which were easily manipulated to obtain films by casting. FOSs were added in different concentrations (0, 1, 5 and 10g/100g solids), and glycerol was used as a plasticizer (20g/100g solids).

Formulations of polymeric biodegradable low-cost foam by melt extrusion to deliver plant growth-promoting bacteria in agricultural systems.

The extrusion technology of blends formed by compounds with different physicochemical properties often results in new materials that present properties distinctive from its original individual constituents. Here, we report the use of melt extrusion of blends made from low-cost materials to produce a biodegradable foam suitable for use as an inoculant carrier of plant growth-promoting bacteria (PGPB). Six formulations were prepared with variable proportions of the raw materials; the resulting physicochemical and structural properties are described, as well as formulation performance in the maintenance of bacterial viability during 120 days of storage.

Cassava starch films containing acetylated starch nanoparticles as reinforcement: Physical and mechanical characterization.

This paper reports the use of acetylated starch nanoparticles (NPAac) as reinforcement in thermoplastic starch films. NPAac with an average size of approximately 500 nm were obtained by nanoprecipitation. Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA) indicated that NPAac are more thermally stable and essentially amorphous when compared with acetylated starch.

Relationships among the composition and physicochemical properties of starches with the characteristics of their films.

The physical, molecular, and functional properties of corn, cassava, and yam starches were related to the film properties of these starches. Corn, cassava, and yam starches contained 25%, 19%, and 30% amylose, respectively. Amylose from yam starch showed the smallest molecular weight among the starches and amylopectin from corn starch the smallest molecular weight.

Effects of yam starch films on storability and quality of fresh strawberries (Fragaria ananassa).

Yam starch films, formulated with yam starch (4.00 g/100 g of solution) and glycerol (1.30 and 2.