Due to their versatility and the high biomass yield produced, cultivation of phototrophic organisms is an increasingly important field. In general, open ponds are chosen to do it because of economic reasons; however, this strategy has several drawbacks such as poor control of culture conditions and a considerable risk of contamination. On the other hand, photobioreactors are an attractive choice to perform cultivation of phototrophic organisms, many times in a large scale and an efficient way. Furthermore, photobioreactors are being increasingly used in bioprocesses to obtain valuable chemical products. In this review, we briefly describe different photobioreactor set‐ups, including some of the recent designs, and their characteristics. Additionally, we discuss the current challenges and advantages that each different type of photobioreactor presents, their applicability in biocatalysis and some modern modeling tools that can be applied to further enhance a certain process.

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Twenty N-fatty acylamines from linolenic and arachidonic acids, fifteen of them new compounds, were obtained through Candida antarctica B lipase-catalyzed esterification and aminolysis reactions in very good yields and with high chemoselectivity. The optimal reaction conditions were achieved by studying the reaction parameters (temperature, E/S ratio, alcohol and alkanolamine/fatty acid ratio, time, solvent, free-solvent system, etc.). To identify ideal enzymatic methods for generating the alkanolamides we evaluated enzyme performance in three procedures: i) aminolysis of ethyl ester, ii) direct condensation between the fatty acid and the alkanolamine, and iii) a

In the last years, there were two fields that experienced an astonishing growth within the biocatalysis community: photobiocatalysis and applications of flow technology to catalytic processes. Therefore, it is not a surprise that the combination of these two research areas also gave place to several recent interesting articles. However, to the best of our knowledge, no review article covering these advances was published so far. Within this review, we present recent and very recent developments in the field of photobiocatalysis in continuous flow, we discuss several different practical applications and features of state-of-the art photobioreactors and lastly, we present some future perspectives in the field.

A series of eleven N‐fatty acid derivatives of vanillylamine was synthesized following an enzymatic approach, in excellent yield and a chemoselective way. The excellent results obtained by catalysis of Thermomyces lanuginosus lipase made the procedure very efficient, considering the low amount of enzyme required and its lower price in comparison with other commercial lipases. The influence of various reaction parameters in the lipase‐catalyzed reactions, such as enzyme source, nucleophile/substrate ratio, enzyme/substrate ratio, solvent and temperature, was studied. In order to evaluate the influence of the fatty acid chain length and configuration on the reaction rate and yield, HPLC analysis and molecular modeling experiments were performed. The results showed that a chain length between 12–14 carbon atoms favors the activity of the enzyme, while insaturation had no effect on the reaction rate. These facts confirm the experimental results. In addition, some of the evaluated compounds exhibited antiviral activity against Herpes simplex virus type 1 (HSV‐1) KOS strain (TK+) and Field and B2006 strains (TK‐) in Vero cells.

Fatty acid photodecarboxylase (FAP) is one of the few photoenzymes in nature. The ability of FAP to convert fatty acids into alka(e)nes without the need for reducing equivalents put this enzyme into spotlight for biocatalytic applications. Although it has been discovered only a few years ago, many studies already emerged demonstrating its potential in areas from biofuel production and enzymatic kinetic resolution to being a critical component of multi-enzyme cascades. While there have been few protein engineering studies for modulating activity of FAP towards very short chain fatty acids, no study has yet addressed substrate selectivity within the medium to long chain fatty acid range, where FAP shows great promise for the synthesis of drop-in biofuels from ubiquitous fatty acids with chain lengths from C12 to C18. Here, after determining optimum expression and assay conditions for FAP, we screened 22 rationally designed mutant enzymes towards four naturally abundant fatty acid substrates; C12 : 0, C16 : 0, C18 : 0 and C18 : 1. Depending on the type of the exchanged amino acid, we observed selectivity shifts towards shorter or longer chains, compared to wild type enzyme. Notably, we obtained two groups of mutants; one group with high selectivity towards only C18 : 0, and another group that is selective towards C12 : 0 substrate. Moreover, we measured light and thermal stability of the wild type enzyme as well as the light stability of a mutant engineered for selectivity.

Alcohol dehydrogenase (ADH) catalyzed reductions in deep eutectic solvents (DESs) may become efficient and sustainable alternatives to afford alcohols. This paper successfully explores the ADH-catalyzed reduction of ketones and aldehydes in a DES composed of choline chloride and 1,4-butanediol, in combination with buffer (Tris-HCl, 20% v/v). 1,4-butanediol (a DES component), acts as a smart cosubstrate for the enzymatic cofactor regeneration, shifting the thermodynamic equilibrium to the product side. By means of the novel DES media, cyclohexanone reduction was optimized to yield maximum productivity with low enzyme amounts (in the range of 10 g L−1 d−1). Notably, with the herein developed reaction media, cinnamaldehyde was reduced to cinnamyl alcohol, an important compound for the fragrance industry, with promising high productivities of ~75 g L−1 d−1.

In this work we present an efficient, environmentally friendly approach to the synthesis of a series of hyodeoxycholic acid derivatives applying Biocatalysis. Fifteen acetyl and ester derivatives, twelve of them new, were obtained through an enzymatic strategy in a fully regioselective way and in very good to excellent yield. In order to find the optimal reaction conditions, the influence of several parameters such as enzyme source, alcohol or acylating agent:substrate ratio, enzyme:substrate ratio, temperature and reaction solvent was considered. The excellent results obtained made this procedure very efficient, particularly considering the low amount of enzyme required. In addition, this methodology uses mild reaction conditions and has reduced environmental impact, making biocatalysis a suitable way to obtaining these bile acids derivatives.