Publications by authors named "Jorge Domínguez-Maldonado"

7 Publications

  • Page 1 of 1

Consolidated Bioprocess for Bioethanol Production from Raw Flour of Seeds Using the Native Strain of Bm-2.

Microorganisms 2019 Oct 23;7(11). Epub 2019 Oct 23.

Renewable Energy Department, Yucatan Center for Scientific Research, Merida 97302, Mexico.

Consolidated bioprocessing (CBP), which integrates biological pretreatment, enzyme production, saccharification, and fermentation, is a promising operational strategy for cost-effective ethanol production from biomass. In this study, the use of a native strain of (Bm-2) was evaluated for bioethanol production from in a CBP. The raw seed flour obtained from the ramon tree contained 61% of starch, indicating its potential as a raw material for bioethanol production. Quantitative assays revealed that the Bm-2 strain produced the amylase enzyme with activity of 193.85 U/mL. The Bm-2 strain showed high tolerance to ethanol stress and was capable of directly producing ethanol from raw flour at a concentration of 13 g/L, with a production yield of 123.4 mL/kg flour. This study demonstrates the potential of Bm-2 for starch-based ethanol production in a consolidated bioprocess to be implemented in the biofuel industry. The residual biomass after fermentation showed an average protein content of 22.5%, suggesting that it could also be considered as a valuable biorefinery co-product for animal feeding.
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http://dx.doi.org/10.3390/microorganisms7110483DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6920830PMC
October 2019

Influence of two polarization potentials on a bioanode microbial community isolated from a hypersaline coastal lagoon of the Yucatan peninsula, in México.

Sci Total Environ 2019 Sep 10;681:258-266. Epub 2019 May 10.

Renewable Energy, Yucatan Center for Scientific Research (CICY), Carretera Sierra Papacal-Chuburná Puerto, Km 5, Sierra Papacal, Mérida, Yucatán CP 97302, Mexico. Electronic address:

In recent years, halotolerant biofilms have become a subject of interest for its application in Bioelectrochemical systems for wastewater treatment. To determine if the polarization potential affects the microbial community of a halotolerant bioanode, four bioanodes were poised at potentials of +0.34 V/SHE and - 0.16 V/SHE and the 16S rRNA gene was analyzed through a MiSeq (Ilumina) system. Oceanospirillum, Halomonas and Marinobacterium were the most predominant genus; no previous studies have reported the presence of Oceanospirillum in anodic biofilms. The fitness with the dataset for +0.34 V/SHE with a modified Butler Volmer Monod model, gives a value of K was 0.0002 (2.64 A m and 38% coulombic efficiency), indicating the fastest electrochemical reaction. Whereas that -0.16 V/SHE case, the high value of K (12.2 with 1.82 A m and 10% coulombic efficiency) indicated that the electron transfer was far from being reversible (Nernstian).
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http://dx.doi.org/10.1016/j.scitotenv.2019.05.120DOI Listing
September 2019

Corn industrial wastewater (nejayote): a promising substrate in Mexico for methane production in a coupled system (APCR-UASB).

Environ Sci Pollut Res Int 2018 Jan 23;25(1):712-722. Epub 2017 Oct 23.

Renewable Energy Unit, Yucatan Center for Scientific Research (CICY), Street 43 N.130 Col. Chuburná de Hidalgo, 97205, Merida, Yucatan, Mexico.

In Mexico, the corn tortilla is a food of great economic importance. Corn tortilla production generates about 1500-2000 m of wastewater per 600 tons of processed corn. Although this wastewater (also known as nejayote) has a high organic matter content, few studies in Mexico have analyzed its treatment. This study presents fresh data on the potential methane production capacity of nejayote in a two-phase anaerobic digestion system using an Anaerobic-Packed Column Reactor (APCR) to optimize the acidogenic phase and an up-flow anaerobic sludge blanket (UASB) reactor to enhance the methanogenic process. Results indicate that day 8 was ideal to couple the APCR to the UASB reactor. This allowed for a 19-day treatment that yielded 96% COD removal and generated a biogas containing 84% methane. The methane yield was 282 L kg of COD. Thus, two-phase anaerobic digestion is an efficient process to treat nejayote; furthermore, this study demonstrated the possibility of using an industrial application by coupling the APCR to the UASB reactor system, in order to assess its feasibility for biomethane generation as a sustainable bioenergy source.
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http://dx.doi.org/10.1007/s11356-017-0479-zDOI Listing
January 2018

Pretreatment of vinasse from the sugar refinery industry under non-sterile conditions by in a fluidized bed bioreactor and its effect when coupled to an UASB reactor.

J Biol Eng 2017 23;11. Epub 2017 Jan 23.

Yucatan center for scientific research (CICY), Renewable Energy Unit and Biotechnology Unit. Street 43 N.130 Col. Chuburná de Hidalgo 97200, Merida, Yucatan Mexico.

Background: During hydrous ethanol production from the sugar refinery industry in Mexico, vinasse is generated. Phenolic compounds and melanoidins contribute to its color and make degradation of the vinasse a difficult task. Although anaerobic digestion (AD) is feasible for vinasse treatment, the presence of recalcitrant compounds can be toxic or inhibitory for anaerobic microorganism. Therefore, this study presents new data on the coupled of the FBR (Fluidized Bed Bioreactor) to the UASB (Upflow Anaerobic Sludge Blanket) reactor under non-sterile conditions by . Nevertheless, for an industrial application, it is necessary to evaluate the performance in this kind of proposal system.

Results: Therefore, this study used a FBR for the removal of phenolic compounds (67%) and COD (38%) at non-sterile conditions. Continuous operation of the FBR was successfully for 26 days according to the literature. When the FBR was coupled to the UASB reactor, we obtained a better quality of effluent, furthermore methane content and yield were 74% and 0.18 m CH/ kg COD respectively.

Conclusions: This study demonstrated the possibility of using for an industrial application the coupled of the FBR to the UASB reactor under non-sterile conditions. Continuous operation of the FBR was carried out successfully for 26 days, which is the highest value found in the literature.
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http://dx.doi.org/10.1186/s13036-016-0042-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5259878PMC
January 2017

Removal of organic matter and electricity generation of sediments from Progreso, Yucatan, Mexico, in a sediment microbial fuel cell.

Environ Sci Pollut Res Int 2017 Feb 7;24(6):5868-5876. Epub 2017 Jan 7.

Unidad de Energía Renovable, Centro de Investigación Científica de Yucatán, Carretera Sierra Papacal-Chuburná Puerto Km 5, 97302, Sierra Papacal, Yucatán, Mexico.

Sediment microbial fuel cells (SMFCs) are devices that generate electrical energy through sediments rich in organic matter (OM). The present study assessed the potential of sediments collected at two sites in Yucatan, Mexico, (the swamp of Progreso port and Yucalpetén dock) to be used in these electrochemical devices. Sediments were collected during the rainy and winter seasons and were monitored in the SMFC for 120 days through electrochemical and physicochemical characterization. OM removal in the SMFC ranged from 8.1-18.01%, generating a maximum current density of 232.46 mA/cm and power density of 95.85 mW/cm. SUVA analysis indicated that with a young soil, the ratio E4/E6 presented evidence directly related to the degradation of aromatic and aliphatic compound formation, implying humification and, therefore, sediment enrichment.
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http://dx.doi.org/10.1007/s11356-016-8286-5DOI Listing
February 2017

Characterization of anode and anolyte community growth and the impact of impedance in a microbial fuel cell.

BMC Biotechnol 2014 Dec 9;14:102. Epub 2014 Dec 9.

Renewable Energy Unit, Centro de Investigación Científica de Yucatán A.C (CICY), Calle 43 No. 130 Col. Chuburná de Hidalgo, C.P. 97200, Mérida, Yucatán, México.

Background: A laboratory-scale two-chamber microbial fuel cell employing an aerated cathode with no catalyst was inoculated with mixed inoculum and acetate as the carbon source. Electrochemical impedance spectroscopy (EIS) was used to study the behavior of the MFC during initial biofilm (week 1) and maximum power density (week 20). EIS were performed on the anode chamber, biofilm (without anolyte) and anolyte (without biofilm). Nyquist plots of the EIS data were fitted with two equivalent electrical circuits to estimate the contributions of intrinsic resistances to the overall internal MFC impedance at weeks 1 and 20, respectively.

Results: The results showed that the system tended to increase power density from 15 ± 3 (week 1) to 100 ± 15 mW/m(2) (week 20) and current density 211 ± 7 (week 1) to 347 ± 29 mA/m(2) (week 20). The Samples were identified by pyrosequencing of the 16S rRNA gene and showed that initial inoculum (week 1) was constituted by Proteobacteria (40%), Bacteroidetes (22%) and Firmicutes (18%). At week 20, Proteobacterial species were predominant (60%) for electricity generation in the anode biofilm, being 51% Rhodopseudomonas palustris. Meanwhile on anolyte, Firmicutes phylum was predominant with Bacillus sp. This study proved that under the experimental conditions used there is an important contribution from the interaction of the biofilm and the anolyte on cell performance. Table 1 presents a summary of the specific influence of each element of the system under study.

Conclusions: The results showed certain members of the bacterial electrode community increased in relative abundance from the initial inoculum. For example, Proteobacterial species are important for electricity generation in the anode biofilms and Firmicutes phylum was predominant on anolyte to transfer electron. R1 is the same in the three systems and no variation is observed over time. The biofilm makes a significant contribution to the charge transfer processes at the electrode (R2 and Cdl) and, consequently, on the performance of the anode chamber. The biofilm can act as a barrier which reduces diffusion of the anolyte towards the electrode, all the while behaving like a porous material. The anolyte and its interaction with the biofilm exert a considerable influence on diffusion processes, given that it presents the highest values for Rd which increased at week 20.
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http://dx.doi.org/10.1186/s12896-014-0102-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4299683PMC
December 2014

Vinasses: characterization and treatments.

Waste Manag Res 2011 Dec 17;29(12):1235-50. Epub 2011 Jan 17.

Unidad de Energía Renovable, Centro de Investigación Científica de Yucatán A. C. (CICY), Mérida, Yucatán, México.

The final products of the ethanol industry are alcoholic beverages, industrial ethanol and biofuels. They are produced by the same production process, which includes fermentation and distillation of raw materials which come from plant biomass. At the end of the distillation process a waste effluent is obtained called vinasse or stillage. The direct disposal of stillages on land or in groundwater (rivers, streams or lakes), or even for the direct irrigation of crops, pollutes the environment due to their high organic contents, dissolved solids and many other compounds which are toxic or could be contaminants under certain environmental conditions. This work reviews the characterization of vinasses from different feedstock sources and the main treatments for conditioning the soluble solids of vinasses before their disposal.
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http://dx.doi.org/10.1177/0734242X10387313DOI Listing
December 2011