First Evaluation of Associated Gut Microbiota in Wild Thick-Lipped Grey Mullets (Chelon labrosus, Risso 1827)

This study aimed to characterize the intestinal microbiota of wild thick-lipped grey mullets (Chelon labrosus) and explore its potential functionality on the host. Intestinal contents of anterior and posterior sections from wild fish were collected and DNA was extracted. Subsequently, the V3–V4 regions of 16S rRNA were sequenced using the Illumina technology and results were analyzed by bioinformatics pipeline. The functional profile of the microbial community was analyzed using PICRUSt software. Shannon and Simpson diversity indices were significantly higher in the posterior section of wild specimens. The overall taxonomic composition suggests a certain homogeneity in the anterior section of the intestine and heterogeneity in the posterior section. Due to this, no statistical differences were detected at any level among both intestinal sections. Predicted functions of intestinal microbiota showed the most abundant were those related to amino acid metabolism, carbohydrate metabolism, energy metabolism, membrane transport, and cell replication and repair. Furthermore, the analysis revealed microbial functional genes related to the elimination of environmental toxins.This work was financed by the Project ‘Design and evaluation of probiotics and feed in uncoupled aquaponic system of fishes, plants and microalgae’ (grant #Agl-2017-83260R) granted by Agencia Estatal de Investigación (MINECO, Spanish Government), and by the Project Bluemaro (PID2020 116136 RB100) of the Ministry of Science and Innovation of Spain. Partial funding for open access charge: Universidad de Málag

Selective chromo-fluorogenic detection of trivalent cations in aqueous environments using a dehydration reaction

[EN] Trivalent cations (Al3+, Fe3+, Cr3+, As3+, In3+ and Ga3+) induced a dehydration reaction of a chemodosimeter in water that is coupled with colour and emission changes.Financial support from the Spanish Government and FEDER funds (Project MAT2015-64139-C4-1) and the Generalitat Valencia (Project PROMETEO II/2014/047) is gratefully acknowledged. M. L. P. is grateful to the Generalitat Valenciana for her Santiago Grisolia grant.Lo-Presti, M.; El Sayed Shehata Nasr, S.; Martínez-Máñez, R.; Costero, AM.; Gil, S.; Parra, M.; Sancenón Galarza, F. (2016). Selective chromo-fluorogenic detection of trivalent cations in aqueous environments using a dehydration reaction. New Journal of Chemistry. 40(11):9042-9045. https://doi.org/10.1039/c6nj01957aS90429045401

2,4-dinitrophenyl ether-containing chemodosimeters for the selective and sensitive 'in vitro' and 'in vivo' detection of hydrogen sulfide

[EN] Four probes (i.e. D1¿D4) for the selective and sensitive fluorogenic detection of HS2 have been prepared and characterised. HEPES (10 mM, pH 7.4)¿DMSO 99:1 v/v solutions of D1¿D4 are essentially non-fluorescent. Changes in the emission using D1¿D4 in the presence of anions (F2, Cl2, Br2, I2, N2 3 , CN2, SCN2, AcO2, CO22 3 , PO22 4 , SO22 4 , HS2 and OH2), biothiols (GSH, Cys, Hcy, Me ¿Cys and lipoic acid), reducing agents (SO22 3 and S2O22 3 ) and oxidants (H2O2) demonstrated that only HS2 is able to induce the appearance of intense emission bands in the 400¿ 520 nm range in the four probes. The selectivity observed was ascribed to a unique hydrogen sulfide-induced hydrolysis of the 2,4-dinitrophenyl ether moiety that yielded the corresponding free highly fluorescent alcohols. The potential detection of intracellular HS2 was also studied.Financial support from the Spanish Government (Project MAT2012-38429-C04-01) and the Generalitat Valencia (Project PROMETEO/2009/016) is gratefully acknowledged. S.E. is grateful to the Generalitat Valenciana for his Santiago Grisolia fellow. L.E.S.F. also thanks the Carolina Foundation and UPNFM-Honduras for his doctoral grant.El Sayed Shehata Nasr, S.; De La Torre, C.; Santos Figueroa, LE.; Martínez-Máñez, R.; Sancenón Galarza, F.; Orzáez, M.; Costero, AM.... (2015). 2,4-dinitrophenyl ether-containing chemodosimeters for the selective and sensitive 'in vitro' and 'in vivo' detection of hydrogen sulfide. Supramolecular Chemistry. 27(4):244-254. https://doi.org/10.1080/10610278.2014.977286S24425427

Combined dietary administration of Chlorella fusca and ethanol-inactivated Vibrio proteolyticus modulates intestinal microbiota and gene expression in Chelon labrosus

The use of functional feeds in aquaculture is currently increasing. This study aimed to assess the combined impact of dietary green microalgae Chlorella fusca and ethanol-inactivated Vibrio proteolyticus DCF12.2 (CVP diet) on thick-lipped grey mullet (Chelon labrosus) juvenile fish. The effects on intestinal microbiota and the transcription of genes related to metabolism, stress, and the immune system were investigated after 90 days of feeding. Additionally, the fish were challenged with Aeromonas hydrophila and polyinosinic–polycytidylic acid (poly I:C) to evaluate the immune response. Microbiota analysis revealed no significant differences in alpha and beta diversity between the anterior and posterior intestinal sections of fish fed the control (CT) and CVP diets. The dominant genera varied between the groups; Pseudomonas and Brevinema were most abundant in the CVP group, whereas Brevinema, Cetobacterium, and Pseudomonas were predominant in the CT group. However, microbial functionality remained unaltered. Gene expression analysis indicated notable changes in hif3α, mhcII, abcb1, mx, and tnfα genes in different fish organs on the CVP diet. In the head kidney, gene expression variations were observed following challenges with A. hydrophila or poly I:C, with higher peak values seen in fish injected with poly I:C. Moreover, c3 mRNA levels were significantly up-regulated in the CVP group 72 h post-A. hydrophila challenge. To conclude, incorporating C. fusca with V. proteolyticus in C. labrosus diet affected the microbial species composition in the intestine while preserving its functionality. In terms of gene expression, the combined diet effectively regulated the transcription of stress and immune-related genes, suggesting potential enhancement of fish resistance against stress and infections