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In the present work, bioethanol was produced by sugar fermentation obtained from water hyacinth using a novelty hybrid method composed of steam explosion and enzymatic hydrolysis, using hydrolytic enzymes produced by solid-state fermentation and water hyacinth as substrate. The highest activity, 42 U for xylanase and 2 U for cellulase per gram of dry matter, respectively, was obtained. Steam explosion pretreatment was performed at 190 ℃ for 1, 5, and 10 min, using water hyacinth sampled from the Maria Lizamba Lagoon, the Arroyo Hondo and the Amapa River. The highest amounts of reducing sugars of water hyacinth were obtained form the samples from the lagoon (5.4 g/50 g of dry matter) after 10 min of treatment. Steamed biomass was hydrolysed using the enzymes obtained by solid-state fermentation, obtained reducing sugars (maximum 15.5 g/L); the efficiency of enzymatic hydrolysis was 0.51 g of reducing sugars per gram of water hyacinth. Finally, reducing sugars were fermented using Saccharomyces cerevisiae for conversion to ethanol, with the highest ethanol concentration (7.13 g/L) and an ethanol yield of 0.23 g/g of dry matter.

The aim of the present study was to evaluate the potential of oils from agricultural residues, such as Mangifera indica L. (mango) and Carica papaya (papaya) from the Papaloapan region, Mexico, as a carbon source for the production of hydrocarbon-degrading (hydrocarbonoclastic) microorganisms in an airlift bioreactor via a common metabolic pathway for hydrocarbons and fatty acids. Biomass growth and carbon source uptake were measured using optical density and gas chromatography, respectively. Gompertz, logistic, and Von Bertalanffy mathematical models were used to obtain kinetic parameters such as the lag phase, maximum specific growth, and consumption rate. The hydrocarbonoclastic consortium was able to grow using papaya (6.09 ± 0.23 g L −1) and mango (2.59 ± 0.30 g L −1) oils, which contain certain antibacterial fatty acids. Differences observed in maximum specific growth and consumption rates indicate that, although mango oil was consumed faster (0.33 day −1 for mango and 0.25 day −1 for papaya), papaya oil provided a higher rate of biomass production per microorganism (0.24 day −1 for mango and 0.44 day −1 for papaya). Additionally, the consortium was able to consume 13 g L −1 diesel as a sole carbon source and improve its maximum specific consumption rate following growth using the oils. Furthermore, the maximum specific growth rate was decreased, indicating a change in the consortium capabilities. Nevertheless, agricultural waste oils from the Papaloapan region can be used to cultivate hydrocarbonoclastic microorganisms. The present study creates the possibility of investigating carbon sources other than hydrocarbons for the production of hydrocarbonoclastic microorganisms.

The potential use of maltodextrin (MD) and sweet potato starch (SPS) mixtures to encapsulate betacyanine from a beetroot extract by the spray‐drying (SD) process was studied. As the SPS content increased in the mixtures, the powder recovery, moisture content, hygroscopicity, porosity, and solubility increased, whereas the values of wettability decreased. The encapsulated betacyanine content increased with the content of SPS in the mixtures, increasing antioxidant activity. The reconstituted powders of MD/SPS mixtures in water showed non‐Newtonian shear‐thinning and a predominant viscous behavior in the rheological tests, except for the sample with 100% SPS, which showed characteristics of a gel. The morphology of the microparticles was shown to depend on the SPS content with a tendency of the particles to aggregate FT‐IR analysis showed that the signals of specific groups of betanins were diminished, which is evidence of the microencapsulation of the betanins, and this was corroborated by transmission electronic microscopy. Practical applications Nowadays, the use of mixtures of biopolymers as encapsulating wall materials is highly appreciated by the food and pharmaceutical industries. This research demonstrated that mixtures of sweet potato starch and maltodextrin at different content ratios are suitable for the microencapsulation of betanins to prepare natural pigments delivery systems with potential applications in functional foods, antioxidants systems, and pharmaceuticals. These systems were characterized by several techniques such as rheology, morphology, FT‐IR, and antioxidant activity in this work. Results of this investigation may help to develop new pigment systems, with potential application as bioactive compounds. Increasing health benefits, including probiotic effects, are expected with the intake of these antioxidants.