The best-known plant endophytes include mainly fungi and bacteria, but there are also a few records of microalgae growing endophytically in vascular land plants, some of which belong to the genus Coccomyxa. In this study, we isolated a single-celled photosynthetic microorganism from the arsenic-tolerant shrub Acacia farnesiana, thus we hypothesized that it is an endophytic arsenic-tolerant microalga. The microorganism was identified as belonging to the genus Coccomyxa, and the observation of algal cells within the root tissues strongly suggests its endophytic nature.
View Article and Find Full Text PDFDibutyl phthalate (DBP) is one of the most abundantly produced and used plasticizers and is incorporated into plastic to make it more flexible and malleable. DBP has been found to be an environmental contaminant and reported as an endocrine disruptor. Therefore, it is crucial to develop ecofriendly alternatives to eliminate phthalate pollution.
View Article and Find Full Text PDFAspergillus is used for the industrial production of enzymes and organic acids, mainly by submerged fermentation (SmF). However, solid-state fermentation (SSF) offers several advantages over SmF. Although differences related to lower catabolite repression and substrate inhibition, as well as higher extracellular enzyme production in SSF compared to SmF have been shown, the mechanisms undelaying such differences are still unknown.
View Article and Find Full Text PDFThe genus Aspergillus is ubiquitous in nature and includes various species extensively exploited industrially due to their ability to produce and secrete a variety of enzymes and metabolites. Most processes are performed in submerged fermentation (SmF); however, solid-state fermentation (SSF) offers several advantages, including lower catabolite repression and substrate inhibition and higher productivity and stability of the enzymes produced. This study aimed to explain the improved metabolic behavior of A.
View Article and Find Full Text PDFAcacia farnesiana is a shrub widely distributed in soils heavily polluted with arsenic in Mexico. However, the mechanisms by which this species tolerates the phytotoxic effects of arsenic are unknown. This study aimed to investigate the tolerance and bioaccumulation of As by A.
View Article and Find Full Text PDFPhytoremediation is a feasible alternative to remediate soils polluted with toxic elements, which can be enhanced by manipulating plant-microbe interactions. Regarding this, free-living saprophytic fungi that interact beneficially with roots have been scarcely studied. Thus, the aim of this study was to assess the effect of a saprophytic fungus, Lewia sp.
View Article and Find Full Text PDFLipases are widely used in the industry for different purposes. Although these enzymes are mainly produced by submerged fermentation, lipase production by solid-state fermentation (SSF) has been gaining interest due to the advantages of this type of culture. Major advantages are higher production titers and productivity, less catabolite repression, and use of the dried fermented material as biocatalyst.
View Article and Find Full Text PDFThe ability of sulfate-reducing bacteria to produce hydrogen sulfide and the high affinity of sulfide to react with divalent metallic cations represent an excellent option to remove heavy metals from wastewater. Different parameters have been proposed to control the hydrogen sulfide production by anaerobic bacteria, such as the organic and sulfate loading rates and the feed COD/SO4(2-) ratio. This work relates the feed COD/SO4(2-) ratio with the hydrogen sulfide production and dissolved lead precipitation, using ethanol as carbon and energy source in an up-flow anaerobic sludge blanket reactor.
View Article and Find Full Text PDFSolid-state microcosms were used to assess the influence of constant and variable C/N ratios on the biodegradation efficiency by Aspergillus niger at high hexadecane (HXD) concentrations (180-717 mg g-1). With a constant C/N ratio, 100% biodegradation (33-44% mineralization) was achieved after 15 days, at rates increasing as the HXD concentration increased. Biomass yields (YX/S) remained almost independent (approximately 0.
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