Juan Carlos Mateos-Díaz

Astaxanthin is an attractive carotenoid that contains beneficial properties as a powerful antioxidant capable of preventing and treating degenerative diseases, while Xanthophyllomyces dendrorhous is one of its main sources. Astaxanthin from X. dendrorhous is generated in response to oxidative or metabolic stress but, to increase the astaxanthin yields, it is necessary to stimulate the metabolic pathway in a way that allows the transcriptional reprogramming of involved genes. Research about the stimulation of carotenoids metabolic pathway posed an important question, could the expression of genes involved in the oxidative stress response be reprogrammed to enhance astaxanthin biosynthesis? Several investigations have demonstrated that astaxanthin biosynthesis is assisted and regulated by electron donor proteins similar to cytochrome P450 reductase (encoded by crtR). Here, we assessed some of these reprogrammed transcriptional responses in wild–type X. dendrorhous under two stimulating conditions: (i) abscisic acid (ABA), and (ii) 6-benzylaminopurine (6-BAP) combined with H₂O₂. mRNA levels of cytochrome P450 genes (CYP51, CYP61, and crtR), electron donor CBR.1, P450 regulator DAP1, and mitochondrial defense genes (CAT, SOD, GPX, and NDUFA), increased during astaxanthin biosynthesis stimulation. The highest stimulating responses were observed using 6-BAP in combination with H₂O₂ between 38 and 50 h of fermentation. Moreover, the profiles of organic acids, glycerol, and volatile compounds were altered, thereby redirecting the carbon flux toward astaxanthin biosynthesis. Nonetheless, the X. dendrorhous wild-type strain required several stimulating agents additions. Astaxanthin overproduction may be achieved by reprogramming the transcriptional levels of genes involved in the biosynthetic pathway, as well as by enhancing cellular responses that mitigate oxidative stress, including those mediated by cytochrome P450 and mitochondrial damage-response proteins. Graphical Abstract

Biotransformation of chlorogenic acid into alkyl caffeates is of great interest due to their valuable biological activities. Aiming to achieve one-pot synthesis of alkyl caffeates from chlorogenic acid, we perform an enzyme and reaction media screening, using the butyl caffeate synthesis as a model reaction. Employing the feruloyl esterase B from Aspergillus terreus (rAtFAEB) in butanol/water (6:1, v/v) mixture, we reached 41% of conversion after 4 h. To achieve higher yields and access biocatalyst recyclability, we decided to fabricate a heterogeneous biocatalyst. After screening 15 immobilization strategies, we concluded that hyper-glycosylation of recombinant rAtFAEB did not allow the proper binding of the enzyme to the supports. Our strategy involved oxidizing the glycosylation of the enzyme to transform the cis-diols of the glycans into aldehydes. The modified enzyme was then immobilized through a covalent bond with aminated supports (MANAE-Agarose and MANAE-Methacrylate) or aminated polycationic matrices. Gloxi-MANAE-Agarose biocatalyst allowed us to access 86% of butyl caffeate conversion after 24 h of reaction. Under the same reaction conditions, further scope studies for various alkyl caffeates showed conversions ranging from 15 to 94%. Testing recyclability, conversion declined to 13% after 4 cycles. This is the first report of a one-pot alkyl caffeate synthesis in solvent-free media using a heterogeneous biocatalyst. Furthermore, our immobilization approach enables the use of hyper-glycosylated enzymes incompatible with standard protocols, overcoming hyper-glycosylation challenges for enzyme immobilization.

Artificial intelligence (AI) is a transformative force across diverse industrial sectors, and fermentation processes are increasingly being optimized through its application in food, pharmaceutical, chemical, and biofuel production. This research aims to conduct a forecasting and publication analysis to elucidate the synergistic relationship between AI and fermentation within the broader context of this knowledge intersection. A comprehensive publication analysis was performed using the Web of Science (WoS) and Scopus databases to characterize the most significant authorship, geographic distribution, and major institutional affiliations, as well as to quantify the research output associated with the intersection of AI and fermentation. In addition, time series forecasting was performed, using triple exponential smoothing (TES), to predict publication trends up to 2030. Furthermore, a comprehensive literature review of diverse recent applications within AI and fermentation was conducted. This study contributes by elucidating global trends in the application of and high-impact research that characterize this specific knowledge intersection. Our findings indicate a substantial and sustained growth trajectory in research output and citation impact related to the convergence of AI and fermentation. This trend is projected to persist until 2030, representing a 48% projected growth from 2024–2030. China and India emerged as leading contributors and financiers in this field. The “Biotechnology & Applied Microbiology” category constitutes approximately one-third of the published articles in the WoS database, while “Chemical Engineering,” “Biochemistry,” and “Engineering” account for the greatest quantity of published articles in the Scopus database.

SARS-CoV-2 has been reported as one of the deadliest viruses in history. Currently, few antiviral treatments are available to prevent SARS-CoV-2 progression to severe disease, especially in low-income countries. Natural products stand as a potential source of bioactive compounds. The antiviral activity against SARS-CoV-2 of Chlorella vulgaris has been demonstrated, however, the nature of its antiviral compounds remains unexplored. In this study, in vitro antiviral activity of extracts and fractions derived from C. vulgaris algae dry powder, was assessed. To determine the in vitro antiviral activity Vero cells were incubated with different concentrations of extracts and fractions against 100 TCID50/ml of SARS-CoV-2 variants. C. vulgaris ethanolic and diethyl ether extracts showed no cytopathic effect in 100% of the replicates. Fractions F11, F12, and F21, composed of high-weight polysaccharides and small proteins, partially protect against viral infection. These results suggest that polysaccharides, proteins, and pigments are related to antiviral activity.

The discovery and design of antiviral agents have gained unprecedented significance due to the emergence of global health threats. The use of synthetic chemistry has enabled the modification of existing molecules and the creation of entirely novel compounds. In our laboratory, we have enzymatically synthesized a novel bioconjugate, lithocholic acid oleate (LO), derived from lithocholic acid (LCA), a bile acid that has been proven by researchers to exhibit antiviral activity in vitro. The study presented herein describes the preparative synthesis, formulation, and evaluation of LO both in vitro and in vivo for its antiviral activity against human herpes simplex virus 1 (HSV-1) as a model of viral infection. Evaluation of cytotoxicity using A549 cells indicated that a combination of LO (400 μM) and LCA (30 μM) exhibited a favorable safety profile while effectively inhibiting HSV-1 infection comparable to acyclovir treatment. Furthermore, in the in vivo assay, animals treated with an oily formulation containing 7% LO; 0.50% LCA; and 3% oleic acid (OA), 48 h prior to virus exposure, showed results even superior to a 5% acyclovir commercial formulation in terms of scar formation and wound recovery. These promising results enable the development of new preventive products against HSV-1 and probably other viruses.

Glioblastoma is one of the most lethal tumors, displaying striking cellular heterogeneity and drug resistance. The prognosis of patients suffering from glioblastoma after 5 years is only 5%. In the present work, capsaicin analogues bearing modifications on the acyl chain with long-chain fatty acids showed promising anti-tumoral activity by its cytotoxicity on U-87 and U-138 glioblastoma multiforme cells. The capsaicin analogues were enzymatically synthetized with cross-linked enzyme aggregates of lipase B from Candida antarctica (CALB). The catalytic performance of recombinant CALB-CLEAs was compared to their immobilized form on a hydrophobic support. After 72 h of reaction, the synthesis of capsaicin analogues from linoleic acid, docosahexaenoic acid, and punicic acid achieved a maximum conversion of 69.7, 8.3 and 30.3% with CALB-CLEAs, respectively. Similar values were obtained with commercial CALB, with conversion yields of 58.3, 24.2 and 22% for capsaicin analogues from linoleic acid, DHA and punicic acid, respectively. Olvanil and dohevanil had a significant cytotoxic effect on both U-87 and U-138 glioblastoma cells. Irrespective of the immobilization form, CALB is an efficient biocatalyst for the synthesis of anti-tumoral capsaicin derivatives. Key points: • This is the first report concerning the enzymatic synthesis of capsaicin analogues from docosahexaenoic acid and punicic acid with CALB-CLEAs. • The viability U-87 and U-138 glioblastoma cells was significantly affected after incubation with olvanil and dohevanil. • Capsaicin analogues from fatty acids obtained by CALB-CLEAs are promising candidates for therapeutic use as cytotoxic agents in glioblastoma cancer cells.

Natural pigments from haloarchaea are of great interest; bacterioruberin is the major pigment, it shows higher antioxidant power when compared with β-carotene. However, characterization of bacterioruberin and its isomers along with its antioxidant and the matrix metallopeptidase 9 (MMP-9) inhibition activities in extracts from Natronoccoccus sp. TC6 and Halorubrum tebenquichense SU10 was not previously described, being the aim of this work. The carotenoids profile was performed by UV-Vis spectrophotometry, thin-layer chromatography, nuclear magnetic resonance spectroscopy, and high-resolution mass spectrometry (UPLC-ESI-MS/MS). Antioxidant capacity was determined for DPPH, ABTS, and FRAP. In addition, MMP-9 inhibition was studied using docking simulations. The carotenoid profile of studied strains was composed of bacterioruberin, some derivatives like mono, bis, and tris anhydrobacterioruberin, and also some bacterioruberin cis isomers. The carotenoid pools showed antioxidant capacity for DPPH > ABTS > FRAP; Natronococcus sp. TC6 carotenoid pool was better for ABTS and DPPH, while Halorubrum tebenquichense SU10 carotenoid pool was better for FRAP. Additionally, docking and molecular dynamics suggest that bacterioruberin inhibits MMP-9 through hydrophobic interactions near the catalytic site. Bacterioruberin shows the higher binding energy of −8.3 (kcal/mol). The carotenoids profile of both strains was elucidated, their antioxidant activity and singular participation of each carotenoid on MMP-9 in silico inhibition were evaluated.