About 85–90% of the market for new materials in biodegradable packaging is served by various blends and composites containing starch in some portion. In an attempt to satisfy the increasing consumer demand, innovative materials are being developed. This includes the concept of active packaging, which, in addition to protecting, interacts with the packaged product. In this context, flexible films have been prepared from blends of poly(butylene adipate‐co‐terephthalate), thermoplastic starch (TPS), and cellulose nanowhiskers (CNW) at different concentrations (0–3.0 wt %) and with distinct compatibilizing agents (glycerol, stearic acid, and citric acid) by flat extrusion. Palm oil was packaged in the films, and was stored under accelerated oxidation conditions as a model system. The films were also used for packing lettuce. The TPS increased the rate of water vapor permeability of the blends. The micrographs showed the films with very porous surface as a function of the CNW concentration. In addition to the antimicrobial action pronounced within 10 days (fungi—molds and yeasts; bacteria—mesophilic and psychrotrophic), the film showed a prooxidant action, indicating its suitability for fruit and vegetable packaging. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47699.

The effects of aeration and agitation on the properties and production of xanthan gum from crude glycerin biodiesel (CGB) by Xanthomonas campestris mangiferaeindicae 2103 were investigated and optimized using a response surface methodology. The xanthan gum was produced from CGB in a bioreactor at 28 °C for 120 h. Optimization procedures indicated that 0.97 vvm at 497.76 rpm resulted in a xanthan gum production of 5.59 g L(-1) and 1.05 vvm at 484.75 rpm maximized the biomass to 3.26 g L(-1). Moreover, the combination of 1.05 vvm at 499.40 rpm maximized the viscosity of xanthan at 0.5% (m/v), 25 °C, and 25 s(-1) (255.40 mPa s). The other responses did not generate predictive models. Low agitation contributed to the increase of xanthan gum production, biomass, viscosity, molecular mass, and the pyruvic acid concentration. Increases in the agitation contributed to the formation of xanthan gum with high mannose concentration. Decreases in the aeration contributed to the xanthan gum production and the formation of biopolymer with high mannose and glucose concentrations. Increases in aeration contributed to increased biomass, viscosity, and formation of xanthan gum with greater resistance to thermal degradation. Overall, aeration and agitation of CGB fermentation significantly influenced the production of xanthan gum and its properties.

With the aim of producing xanthan gum, the effects of an aqueous shrimp shell extract (SSAE) as the source of carbon and nitrogen on the yield and apparent viscosity of the gums produced by fermentation using three native strains ofXanthomonas campestriswere studied. It was found that the SSAE contained 89.75% moisture, 0.054% ash, 8.069% protein, 0.787 lipids, and 1.337% carbohydrates. Media containing different concentrations of SSAE and supplemented with urea (0.01%) and phosphate (0.1%) were fermented in a shaker, and the results obtained were compared with those obtained from sucrose (control) with the same supplementation and fermentation conditions. Strain 1182 showed the highest yield (4.64 g·L−1) and viscosity (48.53 mPa·s), from the medium containing 10% (w/v) of SSAE. These values were higher than those obtained from the control medium containing sucrose. Shrimp shell is a low cost residue that can be bioconverted into products of high added value such as xanthan gum.

Resumo: Um destino para resíduos agro-industriais é usá-los como substratos fermentescíveis, diminuindo o custo na produção de produtos com alto valor agregado. Este trabalho avaliou a influência da natureza dos resíduos fermentescíveis e das cepas de Xanthomonas sobre a produção e propriedades do biopolímero resultante. A produção foi realizada em agitador orbital (250 rpm / 28 °C / 120 h) por fermentação de sacarose (controle), glicerina residual do biodiesel e resíduo líquido de sisal. Tanto a composição do substrato como as cepas mostraram um forte efeito sobre a produção (0,36-2,40 gL -1 ), viscosidade aparente (13,73 para 36,31 mPa.s) e massa molecular (2,1-5,9 × 10 6 Da) da goma de xantana resultante, não influenciando o comportamento pseudoplástico de soluções aquosas dos biopolímeros. Palavras-chave: Produção, viscosidade e massa molecular. Influence of the Nature Agro-Industrial Waste Fermented by Xanthomonas axonopodis pv. Manihotis the Properties of Xanthan Gums ResultingAbstract: A destination for agro-industrial waste is to use them as fermentation substrates. This work was aimed at evaluating the influence of the nature of the waste fermented by two strains of Xanthomonason on the biopolymer properties. The production was performed in an orbital shaker (250 rpm / 28 °C / 120 h) by fermentation of sucrose (control), crude glycerin from biodiesel and sisal liquid waste. Both the fermented substrate composition and the strains had a strong impact on production (0.36 to 2.40 g.L -1 ), apparent viscosity (13.73 to 36.31 mPa.s) and molecular mass (2.1 to 5.9 × 10 6 Da) of the resulting xanthan gum, but they did not affect the pseudoplastic behavior of aqueous biopolymers solutions.

Resumo: Gomas produzidas por microrganismos são usadas como modificadores de alimentos e a biomassa residual para isolamento de seus constituintes. O objetivo deste trabalho foi produzir e caracterizar biomassa extracelular por fermentação submersa com Lasidioplodia theobromae isolado de cacau da Bahia com morte descendente. Foram testadas quatro fontes de carbono fermentadas a 28 °C, 180 rpm por 72 horas. A que resultou em maior produção de biomassa foi avaliada quanto à variação da concentração e pH. As frações obtidas foram caracterizadas por infravermelho (FTIR) e análise por termogravimetria (TG), composição centesimal e monossacarídica. A fermentação submersa da sacarose comercial a 40 g.L -1 em pH 4,0 por L. theobromae resultou em máxima produção da fração I (8,64g.L ). Os espectros de FTIR mostraram presença de grupos amino, poliois e ésteres, e nas análises termogravimétricas observaram-se três eventos de perda de massa em diferentes intensidades. As frações contêm mesma composição em proporções diferenciadas, sendo fontes de proteínas (19,88-29,45%), lipídios (11,07-28,79%), cinzas (3,55-3,88%), e carboidratos (30,16-37,96%) compostos unicamente de glicose e manose em diferentes proporções, portanto ambas glucomananas. As frações apresentam propriedades e potencial desejáveis para ampla utilização em processos biotecnológicos de alta relevância científica. Palavras-chave: Goma, Lasidioplodia theobromae, biomassa residual. Production and Characterization of Extracellular Biomass Obtained by the Fermentation Submerged with Lasidioplodia theobromae Isolate from CocoaAbstract: Gums produced by microorganisms are used as food improvement agents and the residual biomass is used for the isolation of their constituents. The objective of this work was to produce and characterize fractions of extracellular biomass in submerged fermentation with Lasidioplodia theobromae isolated from cocoa of Bahia with descending death. We tested four carbon sources fermented at 28 °C, 180 rpm for 72 h. The one resulting in greater production of biomass was evaluated with regard to changes in concentration and pH. The fractions obtained were characterized by infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA), percentage composition and monosaccharide. The submerged fermentation by L. theobromae with commercial sucrose at 40 g.L -1 and pH 4.0 led to a maximum production of fraction I (8.64 g.L -1 ), while the fermentation at 50 g.L -1 and pH 5.0 yielded maximum production of fraction II (23.69 g.L -1 ). The FTIR spectra indicated the presence of amino groups, polyols and esters. Three weight loss events with different intensities were observed in the thermogravimetric analysis. The fractions have the same composition, but with different proportions, being sources of protein (19.88-29.45%), lipids (11.07-28.79%), ash (3.55-3.88%), and carbohydrates (30.16-37.96%) made only of glucose and mannose, i.e. they are both glucomannans. The fractions have desirable properties for wide use in biotechnological processes of hi...