RESUMEN
To enhance the enzymatic digestibility of cashew apple bagasse (CAB) feedstock in order to produce sugar fermentation-derived bioproducts, the CAB was subjected to three different pretreatments with the ionic liquid 2-hydroxyl-ethylammonium acetate (2-HEAA) and characterized by FTIR, NMR and chemical methods. All conditions were able to delignify CAB, however the best lignin removal (95.8%) was achieved through the method performed with 8.7% w/w of CAB/2-HEAA ratio at 130°C for 24h. Although the cellulose crystallinity has been increased in CAB treated with the ionic liquid, but this fact did not influence its digestibility. Nevertheless, the pretreatment with 2-HEAA enhanced significantly the cellulose digestibility, increasing the glucose yield from 48 to 747.72mgglucose/gCAB. Furthermore, 2-HEAA pretreatment was efficient even with reused ionic liquid, obtaining high glucose concentration.
Asunto(s)
Anacardium/química , Biotecnología/métodos , Líquidos Iónicos/química , Acetatos/química , Anacardium/metabolismo , Celulasa/química , Celulasa/metabolismo , Celulosa/química , Celulosa/metabolismo , Etanolamina/química , Glucosa/química , Glucosa/metabolismo , Hidrólisis , Residuos Industriales , Lignina/química , Espectroscopía de Resonancia Magnética , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Glycerol, a co-product of the biodiesel industry, may be a suitable raw material for the production of high added-value compounds by the microorganisms. This study aimed to use the glycerol obtained from the biodiesel production process as the main carbon source for biosurfactant production by Bacillus subtilis ATCC 6633. Results indicated that the strain lowered the surface tension of the cell-free fermented broth to 31.5 ± 1.6 mN/m, indicating the production of biosurfactant. The critical micelle concentration (CMC = 33.6 mN/m) obtained was similar to the previously reported for biossurfactants isolated from other Bacillus. The produced biosurfactant was able to emulsify n-hexadecane and soybean oil.
RESUMEN
In this work a low cost medium for the production of a biosurfactant by Bacillus subtilis LAMI005 and the kinetics of surfactin production considering the effect of initial substrate concentration were investigated. First, cashew apple juice supplementation for optimal production of biosurfactant by B. subtilis LAMI005 was studied. The medium formulated with clarified cashew apple juice and distilled water, supplemented with 1.0 g/L of (NH(4))(2)SO(4), proved to be the best among the nutrients evaluated. The crude biosurfactant had the ability to decrease the surface tension of water to 30 dyne/cm, with a critical micelle concentration (CMC) of 63.0 mg/L. Emulsification experiments indicated that this biosurfactant effectively emulsified kerosene (IE(24)=67%) and soybean oil (IE(24)=64%). Furthermore, the emulsion stability was always very high. It was shown by biochemical analysis, IR spectra, that there is no qualitative differences in the composition of the crude biosurfactant from a standard sample of surfactin from B. subtilis.