Júlio Cesar de Carvalho

Potential carbon dioxide fixation by industrially important microalgae

The present study aimed at investigating the carbon metabolism in terms of carbon dioxide fixation and its destination in microalgae cultivations. To this purpose, analysis of growth parameters, media of cultivation, biomass composition and productivity and nutrients balance were performed. Four microalgae suitable for mass cultivation were evaluated: Dunaliella tertiolecta SAD-13.86, Chlorella vulgaris LEB-104, Spirulina platensis LEB-52 and Botryococcus braunii SAG-30.81. Global rates of carbon dioxide and oxygen were determinated by a system developed in our laboratory. B. braunii presented the highest CO(2) fixation rate, followed by S. platensis,D. tertiolecta and C. vulgaris (496.98, 318.61, 272.4 and 251.64 mg L(-1)day(-1), respectively). Carbon dioxide fixated was mainly used for microalgal biomass production. Nitrogen, phosphorus (calcium for D. tertiolecta), potassium and magnesium consumption rates (mg gX(-1)) were evaluated for the four microalgae. Biomass composition presented a predominance of proteins but also a high amount of lipids, especially in D. tertiolecta and B. braunii.

Production of bio-ethanol from soybean molasses by Saccharomyces cerevisiae at laboratory, pilot and industrial scales.

The aim of this work was to develop an economical bioprocess to produce the bio-ethanol from soybean molasses at laboratory, pilot and industrial scales. A strain of Saccharomyces cerevisiae (LPB-SC) was selected and fermentation conditions were defined at the laboratory scale, which included the medium with soluble solids concentration of 30% (w/v), without pH adjustment or supplementation with the mineral sources. The kinetic parameters - ethanol productivity of 8.08g/Lh, YP/S 45.4%, YX/S 0.815%, m 0.27h(-1) and microX 0.0189h(-1) - were determined in a bench scale bioreactor. Ethanol production yields after the scale-up were satisfactory, with small decreases from 169.8L at the laboratory scale to 163.6 and 162.7L of absolute ethanol per ton of dry molasses, obtained at pilot and industrial scales, respectively.

Biopigments from Monascus: strains selection, citrinin production and color stability

Fungi form the genus Monascus are a promising source for natural color additives. However, before effectively applying Monascus to foods, it is important to select strains which produce large amounts of biopigments but little or no citrinin, a mycotoxin usually also produced by these fungi. Also, color stability of these pigments should be properly investigated. In order to compare Monascus strains for biopigment production in solid substrate fermentation (SSF), 4 strains (NRRL 1991, NRRL 2897, CCT 3802 and LPB 31) were cultivated over PDA in Petri dishes, and compared for radial growth velocity. Also, these strains were cultivated over cooked rice, and compared in relation to their capacity to produce biopigments and citrinin. The results showed that the strain LPB 31 is the best strain for biopigment production in SSF, giving both higher pigment concentration and lower citrinin concentration on the extracts, showing that it is a promising strain for production of this bioproduct. Biopigmentassays for heat and pH stability, show that these biopigments are unstable at low pH and high temperatures, but may be successfully used at near-neutrality pHs and in non-thermal processed foods.

Application of the biorefinery concept to produce L-lactic acid from the soybean vinasse at laboratory and pilot scale.

Lactic acid is a product that finds several applications in food, cosmetic, pharmaceutical and chemical industries. The main objective of this work was the development of a bioprocess to produce L(+)-lactic acid using soybean vinasse as substrate. Among ten strains, Lactobacillus agilis LPB 56 was selected for fermentation, due to its ability to metabolize the complex oligosaccharides. Fermentation was conducted without need for supplementary inorganic nitrogen sources or yeast extract. Kinetic and yield parameters determined at laboratory scale were 0.864 and 0.0162 for YP/S and YX/S, 0.0145 g/L h (rx), 1.32 g/L h (rs) and 1.13 g/L h (rp). The use of vinasse enriched with soybean molasses provided higher lactic acid concentration (138 g/L), the best proportion of inoculum being 25% (v/v). After scale-up to a pilot plant, kinetic and yield parameters were 0.849 and 0.0353 for YP/S and YX/S, 0.0278 g/L h (rx), 0.915 g/L h (rs) and 0.863 g/L h (rp).

Downstream process development in biotechnological itaconic acid manufacturing

Itaconic acid is a promising chemical that has a wide range of applications and can be obtained in large scale using fermentation processes. One of the most important uses of this biomonomer is the environmentally sustainable production of biopolymers. Separation of itaconic acid from the fermented broth has a considerable impact in the total production cost. Therefore, optimization and high efficiency downstream processes are technological challenges to make biorefineries sustainable and economically viable. This review describes the current state of the art in recovery and purification for itaconic acid production via bioprocesses. Previous studies on the separation of itaconic acid relying on operations such as crystallization, precipitation, extraction, electrodialysis, diafiltration, pertraction, and adsorption. Although crystallization is a typical method of itaconic acid separation from fermented broth, other methods such as membrane separation and reactive extraction are promising as a recovery steps coupled to the fermentation, potentially enhancing the overall process yield. Another approach is adsorption in fixed bed columns, which efficiently separates itaconic acid. Despite recent advances in separation and recovery methods, there is still space for improvement in IA recovery and purification.

Study of phycocyanin production from Spirulina platensis under different light spectra

The aim of this work was to investigate the production of phycocyanin by Spirulina platensis under different spectra of light. The dependent variables evaluated were the amount of phycocyanin obtained and its purity, demonstrating that there might be a restructuring of phycobilisomes, especially when the culture was subjected to red light, which increased the purity level up to 33% with a reduction of 16% in phycocyanin content, but with higher photosynthetic efficiency compared to natural light.

Torularhodin and Torulene: Bioproduction, Properties and Prospective Applications in Food and Cosmetics - a Review

Torularhodin and torulene are two widespread microbial carotenoids with relatively few studies, as compared to other nutraceutical carotenoids such as β-carotene, lycopene and astaxanthin. Several genera of microorganisms produce it in high concentration (up to 0.1% of the cell dry weight), probably as a protection against photooxidation and free radicals. These pigments, which differ by a terminal carboxylic group, have provitamin-A activity and, being red, have potential use as food and cosmetic color additives. Several factors affect the biosynthesis of these substances, including: the composition of culture media, light irradiation, which may enhance the carotenoid production up to 25% of the non-irradiated cultures, and temperature, which changes the carotenoid balance towards more of the acidic carotenoid (torularhodin) or the hydrocarbon (torulene). The biomass may be directly extracted using non polar solvents such as hexane or a hexane-acetone mixture, without need of cell disruption. Extensive purification is not needed for using the pigments as food or cosmetic additives, but it is still necessary to evaluate the bioactivity of the pigments in humans.

Technological trends and market perspectives for production of microbial oils rich in omega-3

Abstract In recent years, foods that contain omega-3 lipids have emerged as important promoters of human health. These lipids are essential for the functional development of the brain and retina, and reduction of the risk of cardiovascular and Alzheimers diseases. The global market for omega-3 production, particularly docosahexaenoic acid (DHA), saw a large expansion in the last decade due to the increasing use of this lipid as an important component of infant food formulae and supplements. The production of omega-3 lipids from fish and vegetable oil sources has some drawbacks, such as complex purification procedures, unwanted contamination by marine pollutants, reduction or even extinction of several species of fish, and aspects related to sustainability. A promising alternative system for the production of omega-3 lipids is from microbial metabolism of yeast, fungi, or microalgae. The aim of this review is to discuss the various omega-3 sources in the context of the global demand and market potential for these bioactive compounds. To summarize, it is clear that fish and vegetable oil sources will not be sufficient to meet the future needs of the world population. The biotechnological production of single-cell oil comes as a sustainable alternative capable of supplementing the global demand for omega-3, causing less environmental impact.

Respirometric Balance and Carbon Fixation of Industrially Important Algae

Abstract Despite being known for a long time, microalgae are gaining importance in recent decades because of their high capacity to fixate atmospheric carbon, assisting in the reduction of global warming. Concurrently with carbon fixation, the production of compounds of commercial interest and reuse of industrial and domestic wastewater turned microalgal culture into one of the most commented-on subjects in the scientific community. In this chapter the photosynthetic metabolism of microalgae is described and discussed, with emphasis on carbon sequestration. The chapter covers the basics of growing algae, the most influential factors in CO 2 fixation, and quantification methodologies. Practical data on rates of carbon fixation by microalgae are presented, especially those genera of algae with the greatest potential for industrial application: Spirulina , Chlorella , Haematococcus , Dunaliella, and Botryococcus . Finally, aspects of the growing global carbon market and the role microalgal technologies can play are also discussed.

Monitoring fermentation parameters during phytase production in column-type bioreactor using a new data acquisition system

Fermentation parameters for phytase production in column-type bioreactor were monitored using a new data acquisition system. There are a number of studies reporting phytase production in flasks, but a lack of data about microorganism respiration behaviour during phytase production using column bioreactor. The objectives of this work were the monitoration of fermentation parameters during phytase production and its relation with fungal growth and forced air. Phytase production by A. niger FS3 increased with forced air. The O2 consumption and CO2 production during solid-state fermentation were monitored by sensors (in the bottom and top of the columns) linked to controllers, recorded by acquisition software and processed by Fersol2® software tool. Phytase synthesis was associated with fungal growth. Therefore, phytase could be used to estimate FS3 biomass formed in citric pulp degradation.