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Biotechnological production of carotenoids can be affected by cultivation conditions, such as temperature, pH and agitation. The aim of this study was to maximize carotenoid production by Sporidiobolus pararoseus in shake flasks with agroindustrial by-products as substrates. The best conditions were used in a stirred tank fermenter. The medium consisted of corn steep liquor and sugar cane molasses pretreated with sulfuric acid. In order to evaluate the effects of the variables, a central composite rotatable design was used. The highest values of total carotenoids (565 µg L-1), biomass (13.6 g L-1) and Y p/s (10.9 µg g-1) were obtained in Assay 13 at 27.5ºC, 150 rpm and pH=4, in Erlenmeyer flasks. For the best conditions defined for carotenoid productivity and 1.2 vvm in the stirred tank fermenter, the maximum value was 1969.3 µg L-1 of total carotenoids. It was 3.5-fold higher than the value obtained when shake flasks were used.

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Many food, cosmetic and pharmaceutical industries have increased their interest in short-chain esters due to their flavor properties. From the industrial standpoint, enzyme reactions are the most economical strategy to reach green products with neither toxicity nor damage to human health. Isoamyl butyrate (pear flavor) was synthesized by isoamyl alcohol (a byproduct of alcohol production) and butyric acid with the use of the immobilized lipase Lipozyme TL IM and hexane as solvents. Reaction variables (temperature, butyric acid concentration, isoamyl alcohol:butyric acid molar ratio and enzyme concentration) were investigated in ester conversion (%), concentration (mol L-1) and productivity (mmol ester g-1 mixture . h), by applying a sequential strategy of the Fractional Factorial Design (FFD) and the Central Composite Rotatable Design (CCRD). High isoamyl butyrate conversion of 95.8% was achieved at 24 hours. At 3 hours, the highest isoamyl butyrate concentration (1.64 mol L-1) and productivity (0.19 mmol ester g-1 mixture . h) were obtained under different reaction conditions. Due to high specificity and selectivity of lipases, process parameters of this study and their interaction with the Lipozyme TL IM are fundamental to understand and optimize the system so as to achieve maximum yield to scale up. Results show that fusel oil may be recycled by the green chemistry process proposed by this study.

Due to the biological importance of carotenoids, several works have been developed aiming for the reduction of carotenoid degradation, and one notable proposed alternative has been the formation of microcapsules. Therefore, the aim of the current paper was the microencapsulation of carotenogenic extracts from Rhodotorula mucilaginosa and Sporidiobolus pararoseus by a lyophilization method utilizing gum arabic, xanthan gum, sodium alginate and soy protein-like wall materials. The gum arabic showed the greatest efficiency of encapsulation for the R. mucilaginosa (66.3±0.8 %) and S. pararoseus (91.4±0.9 %) carotenogenic extracts, while the soy protein showed the lowest efficiency of encapsulation (40.7±1.1 % for R. mucilaginosa and 68.5±1.5 % for S. pararoseus). Scanning electron micrographs (SEM) showed irregular structure formation that was independent of the material utilized for the encapsulation. In this way, it was possible to observe that the wall materials directly affect the encapsulation efficiencies, morphology, and thermal behavior of the capsules of natural carotenoids.