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Essential oils and aqueous extracts were obtained by hydrodistillation of flowers of red and pink variants of Alpinia purpurata (Zingiberaceae), a widely cultivated tropical ornamental plant. GC/MS analyses revealed the presence of 42 essential oil components with α-pinene, β-pinene and β-caryophyllene being the major constituents. Oils from the red and pink variants presented potent larvicidal activities against 4th instar Aedes aegypti with LC50 values of 80.7 and 71.5 ppm, respectively. Aqueous extracts of the two variants were also active against the dengue mosquito larvae (LC50 values of 18.3 and 12.6%, respectively). Oils and aqueous extracts of both variants showed significant oviposition deterrent effects at concentrations of 100 ppm and 20%, respectively. Oil from the red cultivar inhibited significantly the growth of gram-positive and gram-negative bacteria. The study demonstrates that products with valuable biological activities can be produced from flowers of A. purpurata that are not of commercial quality.

Ethanol production by Saccharomyces cerevisiae UFPEDA1238 was performed in simultaneous saccharification and fermentation of delignified sugarcane bagasse. Temperature (32 °C, 37 °C), agitation (80; 100 rpm), enzymatic load (20 FPU/g cellulose and 10%, v/v β-glucosidase or 10 FPU/g cellulose and 5% β-glucosidase) and composition of culture medium were evaluated. Ethanol concentration, enzymatic convertibility of cellulose and volumetric productivity were higher than 25 g/L, 72% and 0.70 g/L h, respectively, after 30 h, when the culture medium 1 and 20 FPU/g cellulose/10%, v/v β-glucosidase or the culture medium 2 and 10 FPU/g cellulose/5% β-glucosidase were used in SSF at 37 °C and 80 rpm. In the SSF with culture medium 2 (supplemented with ammonium, phosphate, potassium and magnesium), 150 L ethanol/t bagasse was achieved, with minimum enzyme loading (10 FPU/g cellulose and 5%, v/v β-glucosidase) for 8%, w/v of solids, which is often an important requirement to provide cost-efficient second generation ethanol processes.