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Microalgae are emerging sources for sustainable production of bioproducts and bioenergy. However, a problem with its reliable production is the biological contamination of cultures. There are several alternatives to mitigate this problem, such as using axenic cultures, concentrated inocula, or applying chemical control agents, which should be eco-friendly. Neochloris oleoabundans is an oleaginous green microalga with a high potential for biofuel production due to its ability to accumulate neutral lipids, mainly monounsaturated fatty acids. For this reason, the main objective of this article was to evaluate the toxicity of 6 natural terpenes with proven antibacterial activity (α-pinene, β-pinene, limonene, trans-cinnamaldehyde, linalool, and eugenol) towards cultures of this green microalgae, through toxicity analysis to obtain the lethal concentration 50 (LC50). The values for β-pinene and limonene were 17 and 16 ppm, respectively, lower than the levels obtained for α-pinene and trans-cinnamaldehyde, of 65 and 35 ppm, respectively. Eugenol and linalool showed LC50 levels above 250 ppm. These results show that selected terpenes do not present high toxicity against N. oleoabundans. Therefore, they can be a green alternative in the management of the cultures.

The aim of this work was the enhancement of biohydrogen production by an anaerobic bacterial consortium with incorporation of lignin-mediated iron nanoparticles in the fermentation medium. Lignin magnetic nanoparticles (LMNP), identified as magnetite by XRD, exhibited spherical shape and average particle size of 8.6 nm, while lignin non-magnetic nanoparticles (LNMNP) exhibited high agglomeration and an amorphous nature in TEM and XRD, respectively. The fermentation medium (pH 7) was composed of 88% soft drink wastewater (SDW) and 12% corn steep liquor (CSL) and supplemented with NaHCO3 (1.0 g/L) and cysteine-HCl (0.5 g/L). Under optimal conditions, BioH2 production was 17.67 ± 0.54 mL, after 48 h of fermentation at 37 °C. Addition of LMNP and LNMNP increased BioH2 production in 91.0 and 74.3%, respectively. Additionally, 200 mg/L of LMNP and LNMNP in the fermentation medium improved the BioH2 yields (mL H2/g CODremoved) in 2.8- and 2.3-fold, respectively.

The search for renewable and sustainable sources of energy has been one of the main goals of society in recent years, especially to reduce the environmental impacts of fossil fuels. One promising alternative is the production of hydrogen, which does not emit greenhouse gases and can be produced from agro-industrial wastes. The Clostridium genus is recorded as having high hydrogen yields compared to other genus, with several producing species. The objective of this work was to evaluate biohydrogen production potential of four agro-industrial residues, which were soft drink wastewater, corn steep liquor, cheese whey, and expired Guaraná soft drink, using one model strain Clostridium beijerinckii ATCC 8260 and newly isolated Clostridium butyricum DEBB-B348. The agro-industrial wastes were characterised in terms of monosaccharide, organic acid, amino acid, cation, and anion concentrations and compared to the literature. After performing subsequent experimental designs, the significant factors were cheese whey concentration, corn steep liquor concentration, and fermentation time for C. beijerinckii, and corn steep liquor concentration and fermentation time for C. butyricum (p ≤ 0.05), with an R2 of 0.950 and 0.895, respectively. The maximum hydrogen volume production was 18.5 ± 1.68 mL and 27.4 ± 1.84 mL for each strain, respectively. The C. butyricum 16s rRNA gene phylogenetic tree and the carbohydrate, organic acid, and amino acid kinetics of the optimum medium are also presented. These results indicate a potential hydrogen production process utilising less expensive substrates, proposing more proper disposal for agro-industrial wastes and using an isolated strain with high yield.

The generation of agroindustrial byproducts is rising fast worldwide. The slaughter of animals, the production of bioethanol, and the processing of oil palm, cassava, and milk are industrial activities that, in 2019, generated huge amounts of wastewaters, around 2448, 1650, 256, 85, and 0.143 billion liters, respectively. Thus, it is urgent to reduce the environmental impact of these effluents through new integrated processes applying biorefinery and circular economy concepts to produce energy or new products. This review provides the characteristics of some of the most important agro-industrial wastes, including their physicochemical composition, worldwide average production, and possible environmental impacts. In addition, some alternatives for reusing these materials are addressed, focusing mainly on energy savings and the possibilities of generating value-added products. Finally, this review considers recent research and technological innovations and perspectives for the future.

We evaluated the production of bioH2 from Cassava Processing Wastewater (CPW) using three microbial consortia (Vac, Esg, and Lod) from different Brazilian environments. These consortia consisted of bacteria of the genera Clostridium, Sporanaerobacter, Coprococcus, Enterococcus, and others. The CPW was supplemented with nitrogen and used raw or hydrolyzed and sterilized or not. Four independent variables were optimized (Box-Behnken design): pH, temperature, C/N ratio, and inoculum ratio. Three quadratic models were obtained and explain production of bioH2 (R2 of 0.93, 0.87 and 0.82 for the consortia Vac, Esg and Lod, respectively). The quadratic effects were the most significant in comparison to linear effects and interactions. The optimal conditions were: pH: 5.5–7.0; temperature 37-39 °C; inoculum ratio 15%, and C/N ratio 5-3,5. After 48 h, the maximum yields of hydrogen obtained with hydrolyzed and sterilized CPW were 1.82, 1.7 and 1.68 mols of H2/mol of maltose for Lod, Esg and Vac, respectively. While, for the only sterilized substrate the yields are in the range 1.33–1.54 mol H2/mol maltose.

Through solid-state fermentation, the endophytic fungus Diaporthe sp. biotransformed the compound R-(+)-limonene, a great quantity of which is present in orange waste. The fermented orange waste was evaluated to determine its antioxidant potential. Mass spectrometry identified several biotransformation products, which were quantified by gas chromatography. The fermentation process yielded compounds such as limonene-1,2-diol, α-terpineol, (−)-carvone, α-tocopherol, dihydrocarveol and valencene, most of which have already been associated with antioxidant activity. The highest concentration of limonene-1,2-diol produced was 3.02 g/kg of dry substrate and 0.72 g/kg of α-terpineol. The DPPH, ORAC and CUPRAC methods were employed to analyze the antioxidant activity comparing the orange waste and the fermented orange waste. According to the results obtained using the DPPH method, the fermented media extract represented 20.17% of antioxidant activity, compared to 12.1% of the orange waste extract, while from the ORAC method analysis the results were 24,011.39 μmolTE/g, obtained from the fermented extract in comparison to 5226.45 μmolTE/g from the orange waste. The results from the CUPRAC method analysis were 538.05 mg TE/g of dry extract, from the fermented extract in comparison to 168.27 TE/g of dry extract, from the orange waste. These results prove that the fermentation process increased the antioxidant potential of the orange waste. Keywords: Limonene, Endophytic fungus, Limonene-1,2-diol, Biotransformation

Palm oil is the primary source of vegetable oil worldwide, with applications in foodstuff, chemicals, and biodiesel production. Its industrial production generates a vast amount of solid and liquid wastes. The most important solid waste is the oil palm empty fruit bunches (OPEFB), and the liquid waste generated in large amounts is the palm oil mill effluent (POME). Both are rich substrates that can be converted into valuable bioproducts; many new technological approaches are being proposed to achieve such a goal, setting up integrated bioprocesses through the biorefinery concept. In this context, this chapter aims to synthesize the most important aspects of palm oil waste reuse and its conversion into valuable biomolecules, considering the aspects of biorefinery and integrated bioprocesses. Among the most important researches reported in this field, some critical results from the Bioprocess Engineering and Biotechnology Group, at UFPR, Brazil are presented. Highlights for the detailed characterization of OPEFB and POME; comparisons between physico-chemical and biological pretreatment of lignocellulosic biomasses from palm wastes; and perspectives of production of biofuels and high value-added biomolecules, such as nano-silver particles and beta-glucans.

The sugarcane industry is one of the largest in the world and processes huge volumes of biomass, especially for ethanol and sugar production. These processes also generate several environmentally harmful solid, liquid, and gaseous wastes. Part of these wastes is reused, but with low-added value technologies, while a large unused fraction continues to impact the environment. In this review, the classic waste reuse routes are outlined, and promising green and circular technologies that can positively impact this sector are discussed. To remain competitive and reduce its environmental impact, the sugarcane industry must embrace technologies for bagasse fractionation and pyrolysis, microalgae cultivation for both CO2 recovery and vinasse treatment, CO2 chemical fixation, energy generation through the anaerobic digestion of vinasse, and genetically improved fermentation yeast strains. Considering the technological maturity, the anaerobic digestion of vinasse emerges as an important solution in the short term. However, the greatest environmental opportunity is to use the pure CO2 from fermentation. The other opportunities still require continued research to reach technological maturity. Intensifying the processes, the exploration of driving-change technologies, and the integration of wastes through biorefinery processes can lead to a more sustainable sugarcane processing industry.

The use of microbial consortia and industrial effluents for the production of biohydrogen by dark fermentation is seen as a key strategy in an attempt to overcome the economic and technical drawbacks of this potential technology. Three mesophilic microbial consortia were sampled and identified. Fermentation was carried out in a vinasse-based medium supplemented with pure or complex carbon sources under different conditions of H2 partial pressure. Consortia LPBAH1 and LPBAH2 were predominantly composed of Oxalobacteraceae and Lactobacillaceae, while LPBAH3 was rich in sporulating Lactobacillaceae (>96%). Each consortium presented specificities related to biohydrogen and VFAs production: (i) the highest biohydrogen yield was achieved with LPBAH1 (>50% Oxalobacteraceae) in a vinasse medium supplemented with sugarcane juice (1.59 ± 0.21 molH2/molglucose); (ii) The lower H2 yields were achieved with LPBAH3, which otherwise produced the highest amount of butyric acid (up to 10 g L−1); (iii) LPBAH2 presented great stability in H2 production in different conditions of H2 partial pressure.

Natural fruity aroma was produced during submerged fermentation by Pichia fermentans using sugarcane molasses as a cultivation broth. The aroma compounds were recovered from the fermentation by a pervaporation process using a polydimethylsiloxane membrane (Pervap 4060-Sulzer). Isoamyl acetate, a characteristic compound associated with fruity aromas, was the major compound produced. The pervaporation module was fed at three different temperatures to test the best conditions to recover the natural fruity aroma. The total flux (J T), partial fluxes of each component (J i), and enrichment factors (β) were determined within the tested ranges. The process was performed at 45 °C, a feed flow of 1.5 mL/min and 0.1 kPa, for a duration of 13 h to concentrate the natural flavor. The pervaporation process can concentrate the isoamyl acetate from fermented broth from 9 to 61.8 mg/L in the first hour of pervaporation. As a single step of downstream operation, pervaporation was efficient for recovering and concentrating the natural fruity aroma. The obtained product was colorless and had a characteristic banana flavor.

Palm oil mill effluent (POME) was tested as a substrate to produce hydrogen by dark fermentation. Two microbial consortia and a pure culture of Clostridium beijerinckii (ATCC 8260) were cultured anaerobically in raw, diluted and hydrolyzed POME to compare biohydrogen production yields in all three media. Experiments were done in 15 mL Hungate tubes containing 5 mL of medium and 1 mL of inoculum. When Clostridium beijerinckii was cultivated at 30 °C in the hydrolyzed POME (P003), containing 7.5 g/L of sucrose, during 8 days of fermentation and 20 % of the inoculum, the maximum biohydrogen production yield was 4.62 LH2/Lmed. Consortium C3 also showed the best production in hydrolyzed POME while consortium C6 achieved its maximum production in raw POME. This effluent is a potential substrate for biohydrogen production.

We present an improved method of direct transesterification suitable for the quantitative analysis of multiple dry samples for its fatty acid content, using a minimal amount of biomass and reactants. The method features an acid-catalyzed direct alcoholysis of microgram samples of dry biomass; the rationale behind the solvent and reagent proportions chosen is discussed. The method was validated using seven microbial strains with diverse lipid content (Saccharomyces cerevisiae, Saccharomyces boulardii, Candida tropicalis, Haematococcus pluvialis, Chlorella vulgaris, Spirulina platensis and Schizochytrium limacinum), and compared with a macroscale direct transesterification method, and with gravimetric analysis of lipids extracted with solvents. The microscale method showed a conversion of 98.06 ± 0.87% of the lipids, using approximately 3 mg of dry biomass, 1mL of 0.2M H2SO4 dissolved in anhydrous ethanol (the acid is the catalyzer and ethanol the reactant)). The mixture was maintained at 70 °C for 20 h with periodic mixing, and then extracted with 2mL n-heptane and analyzed by GC-FID. The lipid content was then calculated considering dilution and sample mass. This method is effective, reliable, and technically attractive for analytical and comparative purposes.

Digestion is a very complex process involving many different enzymes expressed by the human cells and by the microbial community in the digestive tract. Digestive problems such as lactose intolerance and poor digestion of vegetable oligosaccharides affect a great part of the human population, causing discomforts due to their fermentation by gas-producing microorganisms. Although the treatment may involve the supplementation with digestive enzymes, such as lactase (beta-galactosidase) and alpha-galactosidase, respectively, the industrial processing of food products is another alternative. Gluten intolerant and celiac individuals could potentially be benefited by the administration of peptidases or the consumption of peptidase-treated food, however, this is not yet considered a treatment option that substitutes the complete avoidance of gluten. Enzymes have been applied in food processing for various purposes including the removal of undesired components. Besides the galactosidases that remove specific saccharides, another example is the use of l-asparaginase to avoid the formation of acrylamide, a possible carcinogen. In this chapter, the application of digestive enzymes in food bioprocessing will be reviewed, from traditional applications of alpha- and beta-galactosidases, to potential applications of proteases and lipases. Examples of commercial products and of the most recent and relevant patents in this area will be included.

Hydrogen is considered the energy of the future. In order to meet the requirements of a green production, many technological advances were achieved in the last 20 years. Reviewing these advances allows the understanding the constraints of the sector and the identification of the paths for future research. In this work three routes for renewable hydrogen production from renewable sources were reviewed with focus on patented technologies: dissociation of the H2O molecule, microbial production and thermochemical processes. Three patent databases were accessed, covering documents written in English, Spanish and Portuguese. Water dissociation is the only commercial technology and most efforts were identified in new materials for electrodes, new catalysts and reagent recycling. Microbial production is thermodynamic limited but strategies to maximize the production and overcome economic barriers are mostly related to the use of wastewaters, improving microbial communities’ composition and genetic manipulation. Most patents of thermochemical production patents brought contributions to the efficient use of energy especially by the combination with other energy producing technologies. The establishment of a green hydrogen society is strongly dependent of future developments on new materials, recycle of chemical catalysts and efficient use of energy in the short-term.

The use of effluents for hydrogen production through dark fermentation is promising because it results in the generation of value-added products and reduction of the effluent’s organic load. A low-cost medium using agroindustrial effluents, corn steep liquor (CSL) and cassava processing wastewater (CPW) was evaluated for hydrogen production with microbial consortia (Vir and Gal). Four variables were evaluated for their impact on biohydrogen production through a Plackett Burman design. Subsequently, the significant variables were optimized using a central composite design, resulting in two mathematical models with regression coefficients R2 > 0.92. The maximum yields were validated and resulted in 107 and 83.1 mL of biohydrogen/g COD removed for Vir and Gal, respectively. The lower medium cost for biohydrogen production was 81.5 USD/m3, approximately 80% more economical than some supplemented media. Finally, the scale-up of the biohydrogen production by consortia to 5L resulted in an increase of more than 40%.

Summary This study describes, for the first time, the potential use of selected lactic acid bacteria (LAB) to conduct improved coffee bean fermentation during on-farm wet processing. Among different strains tested, Lactobacillus plantarum LPBR01 showed a suitable production of organic acids and flavour-active esters in a coffee-pulp simulation medium and was used as starter culture under field conditions. The results indicated that L. plantarum LPBR01 was able to establish an accelerated coffee-pulp acidification process and potentially reduced the fermentation time from 24 to 12 h. The inoculation of LPBR01 strain also increased significantly the formation of volatile aroma compounds during fermentation process (such as ethyl acetate, ethyl isobutyrate and acetaldehyde) and enabled the production of beverage with distinct sensory notes and a remarkable increase in quality compared to the conventional process. Our results suggest that the use of LAB in coffee processing is an ideal alternative way to conduct faster and improved coffee bean fermentation.

The aim of this study was to evaluate the use of different functional substrates (soybean hydrolyzed extract, colostrum and honey) to design novel probiotic beverages using kefir grains as starter culture. The fermentations were carried out at 30 °C for 24 h and physical-chemical composition and functional aspects were determined. It was found that fermentation processes with kefir grains increased the functional quality of all substrates evaluated. Honey-based kefir beverage had higher antioxidant activity and its microbial composition was assessed using molecular approaches (Rep-PCR and 16S rRNA gene sequencing). High levels of lactic acid bacteria and yeast populations (over 106 CFU/mL) were found in the product and were mainly composed of potential probiotic strains of Lactobacillus statsumensis, Leuconostoc mesenteroides, Bacillus megaterium, Saccharomyces cerevisiae and Lachancea fermentati. In addition, the honey-based kefir beverage showed protection effect on DNA damage and had a high sensory quality compared to traditional kefir beverage. The results demonstrated that honey could be an ideal alternative substrate for the production of functional cultured beverage, especially for vegans and lactose intolerant consumers.

Terpenoids are important ingredients in perfumery, and terpene residues have shown potential as new sources of these compounds. This study aimed to apply gas extraction with liquefied petroleum gas (butane/propane) as a clean technology to extract terpenes from agroindustrial and forest wastes. The extracts obtained were characterized by gas chromatography–mass spectrometry (GC–MS), and compared to extracts obtained using traditional organic solvent extraction (hexane and dichloromethane: n -pentane). The oil extraction yields were 5.36% for the orange waste, 2.1% for the apple pomace, 2.32% for the pine needle and 0.6% for the pine wood shavings. The extract obtained using this new method on orange waste contained the highest concentration of limonene (95.32 g/100 g of extract), α-pinene (0.40) and β-pinene (0.23) among all of the solvents as well as the largest extracted amount (0.051 g/g of dry substrate). Based on the GC–MS analyses, the LPG extraction displayed less decomposition or modification of the compounds.

Biohydrogen production was evaluated using cassava processing wastewater (CPW) and two microbial consortia (Vir and Gal) from different Brazilian environments. The biohydrogen production was optimized using a Box-Behnken design (T, pH, C/N, and % v/v inoculum). Maximum yields were obtained with hydrolyzed substrate: 4.12 and 3.80 mol H2 / for Vir and Gal, respectively. Similarly, the kinetic parameters µ, k, and q were higher with hydrolyzed CPW in both consortia. The molecular analysis of the consortia through Illumina high-throughput sequencing showed the presence of bacteria from the families Porphyromonadaceae, Clostridiaceae, Ruminococcaceae, and Enterococcaceae. The relative abundance of microbial families varies as fermentation progresses. In both consortia, Clostridiaceae reached the maximum relative abundance in the media between 16 and 24 h, interval in which approximately 90% of the biohydrogen is generated.

A new method for CO2 recovery was proposed for cultivation of different microalgae. First, a chemical fixation, where CO2 was injected in alkalinized vinasse to form (bi)carbonate salts, was performed. In addition, biological fixation with CO2-enriched air injection was also accomplished for evaluation of the most promising results. Two bioreactor systems, a stirred-tank reactor and a bubble column reactor, were employed. A higher carbon transfer rate (43.35 g.L−1.h−1) was achieved in the bubble column reactor using NaOH-alkalinized vinasse, along with reductions of the chemical oxygen demand (COD), biological oxygen demand (BOD) and turbidity (TD). This allowed the cultivation of microalgae and cyanobacteria at vinasse concentrations between 70 and 100%, reaching a biomass production of 2.25 g.L−1 in 15 days of culture. The viability of chemical CO2 fixation together with the use of 100% treated vinasse from a bioethanol production unit for microalgae cultivation has been demonstrated in a successfully integrated biorefinery approach.

The global market for mushroom production has grown significantly for edible mushrooms, mostly for the production of enzymes and other valuable biomolecules, notably biocompounds for human health. Solid-state fermentation is the most suitable fermentation technique to cultivate mushrooms, and many technological advances have taken place in the last few years, allowing the identification of new species by direct and indirect methods. Creation of strain culture collections and gene banks, development of new molecular biology techniques, and better understanding of cellular physiology and metabolism have been key factors to these advances. Moreover, the economic value of mushrooms, their important role as environmentally friendly agents has been explored in controlled processes, like composting and bioremediation. However, there is still much research to be done, and further scientific and technological advances are expected to be made, always taking into account technical, political, economic, legal, and social aspects.

The aim of this review is to describe the volatile aroma compounds of green coffee beans and evaluate sources of variation in the formation and development of coffee aroma through postharvest processing. The findings of this survey showed that the volatile constituents of green coffee beans (e.g., alcohols, aldehydes, and alkanes) have no significant influence on the final coffee aroma composition, as only a few such compounds remain in the beans after roasting. On the other hand, microbial-derived, odor-active compounds produced during removal of the fruit mucilage layer, including esters, higher alcohols, aldehydes, and ketones, can be detected in the final coffee product. Many postharvest processing including drying and storage processes could influence the levels of coffee aroma compositions, which remain to be elucidated. Better understanding of the effect of these processes on coffee aroma composition would assist coffee producers in the optimal selection of postharvest parameters that favor the consistent production of flavorful coffee beans.

Banana is one of the most important fruits in the Brazilian diet and is mainly consumed naturally. Losses from crop to final consumer are high and estimated in about 30%. The aim of this work was to elaborate a distilled alcoholic beverage from discarded banana and to compare with commercial trademarks. Initially, yeast strains were isolated from banana fruit and characterized by their production of volatile aroma compounds. The highest aroma-producing yeast isolate was identified by ITS-rRNA gene sequencing as Pichia kluyveri. Pasteurized banana pulp and peel was fermented by the selected P. kluyveri at approximately 107 cells/mL. The sugars were converted quickly, and a high ethanol concentration (413 mg/L) was achieved after 24 h of fermentation. The fermented banana must was distilled in a Femel Alambic, and the head, heart and tail fractions were collected. The banana brandy produced had highest concentration of volatile compounds compared to trademarks, such as isoamyl acetate (13.5 mg/L), ethyl hexanoate (0.8 mg/L) and others. The results showed that whole banana must could be a good substrate for fermentation and distillation, and the sensory analysis performed revealed that the produced beverage had good acceptance by the tasters. This study demonstrates the potential of banana as a possible alternative to reduce waste and increase income to farmers.

Isolation and purification processes, also known as downstream processes, are a critical and costly step in bioprocesses. They are the appropriate sequence of separation operations, such as centrifugation, adsorption, chromatography, and drying, which will lead from a mixture of several components from the fermentation or biotransformation to a final product. This chapter briefly discusses the importance of knowing the properties of the molecules to be isolated, the driving forces, and the general aspects of classical bioseparations. After that, it discusses some heuristic strategies for linking different operations in an integrated process. Finally, new operations and trends in bioseparations, such as single-use systems and automation, are discussed.

Industrial citric acid (CA) production started nearly 100 years ago. CA production is a well-established bioprocess that employs parental or mutant strains of the fungus Aspergillus niger. CA production continues to rise because it exhibits versatility for many applications, primarily in the food, beverage, and pharmaceutical industries. As a result, CA is the most produced organic acid in the world. This chapter presents important information about CA production techniques and conditions and the factors that affect the biochemical pathways and synthesis of this acid and the recovery of the product. The most important applications, the demand for CA, and the manufacturers involved are also described. Alternative solutions for CA production optimization are presented, including strain mutagenesis and cocultures. These strategies are essential for addressing the economic variability of the market, which is significantly influenced by the Chinese market and the low prices of its citrate products.

Cell disruption is an essential step in the production of intracellular products. It consists in permeating or opening the cell, and this can be done using several methods, usually classified as physical, chemical, or mechanical. Not all methods are suitable for large-scale processing, and each one has a different impact on the target product. This chapter discusses the need for cell permeation or disruption, presents the most common methods used in laboratory and process scales, highlights aspects that must be evaluated for choosing a cell disruption method, and briefly comments on the necessary steps following disruption and preceding purification.

Cachaca and rum are distilled alcoholic beverages produced in large quantities from Brazil to the Caribbean. This chapter is dedicated to showing how these spirits are made and their differences in the must production, fermentation conditions (temperature, yeast strains, fermentation schedule), and aging conditions. Many similarities and confusion between these spirits exist because of the raw material (sugarcane) and some steps of the production, but perceptible changes in organoleptic properties can show their differences. Congeners can vary greatly in function of the fermentation and aging conditions, giving each spirit its particularity.

Ultrafiltration is an attractive downstream processing technique for concentrating enzymes and could be considered the primary step of purification. However, the efficiency of this process is often limited by protein fouling and shear-induced enzyme inactivation, which decreases permeate flux and results in the loss of enzyme activity. Although the rejection of phytase was higher than 99%, the loss of the enzyme activity was 14% during operation, indicating that the shear forces generated in the filter have significant influences on the enzyme activity. Two preparations using glycerol (25% and 35%, v/v) as a cryo-protecting agent at different temperatures were studied. The preparation containing 35% glycerol retained 70% of the initial enzyme activity at 70 °C after 1 h and had more than 3 and 6 months storage half-life at 29 °C and 4 °C, respectively.

A successful pilot-scale process for biodiesel production from microbial oil (Biooil) produced by Rhodosporidium toruloides DEBB 5533 is presented. Using fed-batch strategy (1000L working volume), a lipid productivity of 0.44g/L.h was obtained using a low-cost medium composed by sugarcane juice and urea. The microbial oil was used for biodiesel production and its performance was evaluated in diesel engine tests, showing very good performance, especially for the blend B20 SCO, when operating at 2500rpm with lower pollutant emissions (CO2 - 220% less; CO - 7-fold less; NOX 50% less and no detectable HC emissions (

Aroma and fragrances have high commercial value for use in food, cosmetics and perfumes. The biotransformation of terpenes by microorganisms represents an attractive alternative method for production of flavourings. Endophytic fungi offer a great potential for the production of several groups of compounds; however, few studies have evaluated the biotransformation of limonene. Following preliminary studies on the biotransformation of limonene, submerged fermentation was carried out using an endophytic fungus isolated from Pinus taeda and identified as Phomopsis sp. The presence of several biotransformation products was detected and identified by mass spectrometry (GC–MS). The studied strain showed a divergent metabolic behaviour, as compounds of interest such as α-terpineol, carvone, and limoneno-1,2-diol were produced under different conditions. In addition to the minor metabolites terpinen-4-ol, menthol and carveol, this strain also produced major metabolites, including 0.536 g L −1 carvone and 2.08 g L −1 limonene-1,2-diol in synthetic medium and 2.10 g L −1 limonene-1,2-diol in a natural orange extract medium with single fed-batch, while the cyclic fed-batch resulted in concentrations less than 1 g L −1 . Therefore, our study produced a wide variety of limonene derivatives at a high concentration using a natural medium and a newly isolated endophytic fungal strain.

The development of stable enzymes is a key issue in both the food and feed industries. Consequently, the aim of the current study is to evaluate the impact of various additives (sodium chloride, sodium citrate, mannitol, methylparaben, polyethylene glycol 3350, ethylenediaminetetraacetic acid disodium salt, and a serine protease inhibitor) on the stability of a mushroom phytase produced by solid-state cultivation and recovery. Also observed was the effect of the additives on microbial growth inhibition by monitoring both the change in optical density over 30 days of storage and proteolytic activity. Initially, eight experimental formulations were prepared along with a control. After screening, a 3(2) factorial design was applied to define suitable concentrations of the selected additives. Among the eight formulations tested, the formulation containing NaCl, PEG 3350, and methylparaben retained all of the initial phytase activity after 50 days of storage, with no detected interference from protease activity. Sodium citrate, a metal chelation agent, presented the unusual effect of reducing protease activity in the formulations. Although all formulations presented better phytase stability when compared to the control, NaCl and PEG were both able to prolong the stability of the enzyme activity and also to inhibit microbial growth during storage, making them favorable for application as food and feed additives.