Publications by authors named "Raul Tapia-Tussell"

The Sargassum phenomenon is currently affecting the Caribbean in several ways; one of them is the increase of greenhouse gases due to the decomposition process of this macroalgae; these processes also produce large amounts of pollutant leachates, in which several microbial communities are involved. To understand these processes, we conducted a 150-day study on the Sargassum spp environmental degradation under outdoor conditions, during which leachates were collected at 0, 30, 90, and 150 days. Subsequently, a metagenomic study of the microorganisms found in the leachates was carried out, in which changes in the microbial community were observed over time.

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The constant golden tides of spp., identified to be a mixture of and , observed recently in the Mexican Caribbean have affected the marine ecosystem and the local economy and have created the need for solutions for their management and use. The arrivals have thus been considered as third-generation feedstock for biofuel.

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Large volumes of pelagic Sargassum spp. have stranded periodically on the Mexican Caribbean shoreline. The aim of this research was to study the mobility of metals through the leachates released into the environment during the natural decomposition process of Sargassum spp.

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Presence of alternate hosts of plants is a great threat to the agriculture industry. Plants from several species growing in the papaya orchards affected by papaya sticky disease were examined for Papaya meleira virus (PMeV) infection causing this disease. The viral dsRNA was already detected in some plants from the family Poaceae or in watermelon.

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The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in wastewater has been reported as a result of fecal shedding of infected individuals. In this study, the occurrence of SARS-CoV-2 RNA was explored in primary-treated wastewater from two municipal wastewater treatment plants in Quintana Roo, Mexico, along with groundwater from sinkholes, a household well, and submarine groundwater discharges. Physicochemical variables were obtained in situ, and coliphage densities were determined.

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The decolorization of dye and textile effluent by Trametes hirsuta was studied in both induced and non-induced media. A removal of 70-100% of the color was achieved through adsorption and the action of laccases. Laccase activity was increased significantly with the addition of grapefruit peel (4000 U/mL) and effluent with grapefruit peel (16,000 U/mL) in comparison with the basal medium (50 U/mL).

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Micromycetes from unexplored sources represent an opportunity to discover novel natural products to control insect pests. With this aim, a strain of CICY026 isolated from a tropical sinkhole was identified, cultured on fermented rice, and its ethyl acetate extract (EAE) was evaluated against three serious phytophagous insects (, and ). DNA from CICY026 was used to confirm its identity.

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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.

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Papaya meleira virus (PMeV) causes sticky disease in in Brazil and Mexico. Despite its economic importance and the need for effective phytosanitary control, it remains unknown whether any insect is the vector of this virus. The aim of this work was to identify potential insect vectors of the PMeV-Mexican variant (PMeV-Mx) and determine whether these potential vectors are capable of transmitting the virus.

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The increasing incidence of infections and resistance to current antifungal therapies has led to the search for new and more effective antifungal compounds. Actinobacterial species from the genus are recognized as some of the major producers of antimicrobial compounds. Therefore, the aims of this study were: (1) the identification of strains isolated from Mexican tropical acidic soils, (2) the evaluation of their antifungal activity on , and (3) the exploration of the presence of polyketide synthase genes in their genome and antifungal secondary metabolites in their extracts.

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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.

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The aim of this study was to identify and characterize laccase genes produced by Bm-2 in a liquid medium, both with and without induction. The amplification of 5'and 3'regions of laccase sequences was obtained by the RACE-PCR method, and these were assembled to obtain a cDNA of total length. Two new laccase genes were isolated from basal medium (-) and lignocellulosic grapefruit substrate (-), both encoding open reading frames of 2566 bp.

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Looking for a biotechnical potential, aqueous extracts of leaves of 12 native species used in the Mayan traditional medicine of the coastal dune and mangrove of Yucatan (Mexico) were selected to evaluate their biological activities. Rhizophora mangle and Manilkara zapota showed the highest free radical scavenging activity (3.94 ± 0.

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Mexico is one of the five largest producers of papaya worldwide, but losses caused by pathogens, mainly fungus, at the pre- and post-harvest stages are often more than 50% of the crop. Papaya anthracnose, caused by three different species of the Colletotrichum genus in Mexico, occupies a preponderant place in this problem. Although two of these species, C.

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Lignin is a source for obtaining natural phenols with high commercial value that can act as redox mediators enhancing effects in dye decolorization. In this study Bm-2 was grown on wheat bran to produce laccases and phenol extracts (PE). Ultrafiltered phenols obtained at different times were evaluated in their potential as redox mediators of laccase activity and indigo carmin decolorization.

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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.

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Sticky disease, which is caused by Papaya meleira virus (PMeV), is a significant papaya disease in Brazil and Mexico, where it has caused severe economic losses, and it seems to have spread to Central and South America. Studies assessing the pathogen-host interaction at the nano-histological level are needed to better understand the mechanisms that underlie natural resistance. In this study, the topography and mechanical properties of the leaf midribs and latex of healthy and PMeV-infected papaya plants were observed by atomic force microscopy and scanning electron microscopy.

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Vinasse is the dark-colored wastewater that is generated by bioethanol distilleries from feedstock molasses. The vinasse that is generated from molasses contains high amounts of pollutants, including phenolic compounds and melanoindin. The goal of this work was to study the expression of laccase genes in the Trametes hirsuta strain Bm-2, isolated in Yucatan, Mexico, in the presence of phenolic compounds, as well as its effectiveness in removing colorants from vinasse.

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Papaya meleira virus (PMeV) is the causal agent of papaya sticky disease, which is characterized by a spontaneous exudation of fluid and aqueous latex from the papaya fruit and leaves. The latex oxidizes after atmospheric exposure, resulting in a sticky feature on the fruit from which the name of the disease originates. PMeV is an isometric virus particle with a double-stranded RNA (dsRNA) genome of approximately 12 Kb.

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This study characterized Clavispora lusitaniae strains isolated from different stages of the processing and early fermentation of a henequen (Agave fourcroydes) spirit produced in Yucatan, Mexico using a molecular technique. Sixteen strains identified based on morphological features, obtained from different substrates, were typed molecularly. Nine different versions of the divergent D1/D2 domain of the large-subunit ribosomal DNA sequence were identified among the C.

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Background: C. gloeosporioides sensu lato is one of the most economically important post-harvest diseases affecting papaya production worldwide. There is currently no information concerning the genetic structure or demographic history of this pathogen in any of the affected countries.

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Colletotrichum gloeosporioides is the common causal agent of anthracnose in papaya (Carica papaya L.) fruits, and infection by this fungal pathogen results in severe post-harvest losses. In the Yucatán peninsula (Mexico) a different Colletotrichum species was isolated from papaya fruits with atypical anthracnose lesions.

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The molecular characterization of 14 strains of Kluyveromyces marxianus isolated from Agave fourcroydes (Lem.) in Yucatan, Mexico, was performed by AP-PCR analysis, PCR-RFLP of 5.8S-ITS, and complete NTS regions.

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A simple and easy protocol for extracting high-quality DNA from different yeast and filamentous fungal species is described. This method involves two important steps: first, the disruption of cell walls by mechanical means and freezing; and second, the extraction, isolation, and precipitation of genomic DNA. The absorbance ratios (A(260)/A(280)) obtained ranged from 1.

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Genetic studies and pathogen detection in plants using molecular methods require the isolation of DNA from a large number of samples in a short time span. A rapid and versatile protocol for extracting high-quality DNA from different plant species is described. This method yields from 1 to 2 mg of DNA per gram of tissue.

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