Sequential process of solid-state cultivation with fungal consortium and ethanol fermentation by Saccharomyces cerevisiae from sugarcane bagasse.

Solid-state cultivation (SSC) is the microbial growth on solid supports, producing a nutrient-rich solution by cell enzymes that may be further used as a generic microbial medium. "Second-generation" ethanol is obtained by fermentation from mainly the acid hydrolysates of lignocellulosic wastes, generating several microbial growth inhibitors. Thus, this research aimed at evaluating the feasibility of ethanol fermentation from sugarcane bagasse hydrolysate after SSC with vinasse as the impregnating solution by a consortium of A. niger and T. reesei as opposed to the conventional method of acid hydrolysis. Fermentation of the hydrolysate from SSC leading to the yield of 0.40 g g-1, i.e., about 78% of maximum stoichiometric indicating that the nonconventional process allowed the use of two by-products from sugarcane processing in addition to ethanol production from glucose release.

Sugarcane vinasse and microalgal biomass in the production of pectin particles as an alternative soil fertilizer.

High methoxyl pectin was used as biopolymeric matrix to produce a novel slow release soil fertilizer added with sugarcane vinasse and lipid extracted microalgal (Desmodesmus subspicatus) biomass residue (LMBR). Vinasse acted as the biopolymer solvent, providing greater stability to pectin gel, and as a source of nitrogen (N), potassium (K), calcium (Ca) and magnesium (Mg). LMBR (0.5%) was considered a complementary source of N and micronutrients, copper (Cu), iron (Fe) and zinc (Zn). Compared to blank pectin particles, the particles with vinasse and LMBR showed homogeneous polymer matrix, spherical shapes, higher soluble matter release and enhanced mechanical properties. Scanning electron microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR) analysis indicated the incorporation of microalgal biomass and nutrients from vinasse. Higher rates of biodegradation as well as larger degree of mineralization were found over a period of 36 days for vinasse and LMBR particles. These particles exhibit good perspectives as an alternative fertilizer for agriculture applications and represent an innovative solution for vinasse and LMBR final disposal.