Nature And Properties Of Soils

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The revised Trypanosoma cruzi subspecific nomenclature: rationale, epidemiological relevance and research applications.

Fungi are an understudied, biotechnologically valuable group of organisms. Due to 
the immense range of habitats that fungi inhabit, and the consequent need to compete against a diverse array of other fungi, bacteria, and animals, fungi have developed numerous survival mechanisms. The unique attributes of fungi thus herald great promise for their application in biotechnology and industry. Moreover, fungi can be grown with relative ease, making production at scale viable. The search for fungal biodiversity, and the construction of a living fungi collection, both have incredible economic potential in locating organisms with novel industrial uses that will lead to novel products. This manuscript reviews fifty ways in which fungi can potentially be utilized as biotechnology. We provide notes and examples for each potential exploitation and give examples from our own work and the work of other notable researchers. We also provide a flow chart that can be used to convince funding bodies of the importance of fungi for biotechnological research and as potential products. Fungi have provided the world with penicillin, lovastatin, and other globally significant medicines, and they remain an untapped resource with enormous industrial potential.

The amazing potential of fungi: 50 ways we can exploit fungi industrially

Polycyclic aromatic hydrocarbons (PAHs) are widespread across the globe mainly due to long-term anthropogenic sources of pollution. The inherent properties of PAHs such as heterocyclic aromatic ring structures, hydrophobicity, and thermostability have made them recalcitrant and highly persistent in the environment. PAH pollutants have been determined to be highly toxic, mutagenic, carcinogenic, teratogenic, and immunotoxicogenic to various life forms. Therefore, this review discusses the primary sources of PAH emissions, exposure routes, and toxic effects on humans, in particular. This review briefly summarizes the physical and chemical PAH remediation approaches such as membrane filtration, soil washing, adsorption, electrokinetic, thermal, oxidation, and photocatalytic treatments. This review provides a detailed systematic compilation of the eco-friendly biological treatment solutions for remediation of PAHs such as microbial remediation approaches using bacteria, archaea, fungi, algae, and co-cultures. In situ and ex situ biological treatments such as land farming, biostimulation, bioaugmentation, phytoremediation, bioreactor, and vermiremediation approaches are discussed in detail, and a summary of the factors affecting and limiting PAH bioremediation is also discussed. An overview of emerging technologies employing multi-process combinatorial treatment approaches is given, and newer concepts on generation of value-added by-products during PAH remediation are highlighted in this review.

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Polycyclic Aromatic Hydrocarbons: Sources, Toxicity, and Remediation Approaches.

Enzymes in the Environment: Activity, Ecology and Applications Soil Biology and Biochemistry

A degrading microbial consortium highly tolerant to three-, four- and five-ring polycyclic aromatic hydrocarbons (PAHs) was selected from 50 fungal and bacterial isolates obtained from crude oil-contaminated soils Morphological and molecular studies indicated that isolated fungi belonged to genera Aspergillus, Penicillium, Fusarium, Trichoderma, Scedosporium, and Acremonium and bacteria to Pseudomonas, Klebsiella, Bacillus, Enterobacter, Streptomyces, Stenotrophomonas, Kocuria, and Delftia genera Individual fungal and bacterial isolates were evaluated for their potential to tolerate high concentrations of different molecular weight PAHs, as phenantrene (Phe), pyrene (Pyr), and benzo[a]pyrene (BaP) by surface plate assays, showing significant differences in extension rates for fungi and inhibition ratios for bacteria when both were exposed to 0–6,000 mg of PAHs per liter Trichoderma asperellum H15, Aspergillus nomius H7, Aspergillus flavus H6, Pseudomonas aeruginosa B7, Klebsiella sp B10, and Stenotrophomonas maltophilia B14 grew using PAHs as sole carbon source and presented a remarkably high tolerance to PAHs, up to 6,000 mg l−1 The consortium composed of 12 fungal and bacterial PAH-tolerant isolates for the bioremediation of a PAH-contaminated soiled to a removal of 8776 % Phe, 4818 % Pyr, and 5655 % BaP after 14 days The degrading microbial consortium presented high potential for bioremediation and may be useful for the treatment of sites polluted with PAHs due to their elevated tolerance to high molecular weight (HMW) PAHs and their capacity to utilize them as energy source This is the first study which evaluated the microbial tolerance to extreme concentrations of PAHs, resulting in a degrading consortium and highly tolerant consortium compared with those reported in other studies, where the concentrations tested are low

Isolation and Selection of a Highly Tolerant Microbial Consortium with Potential for PAH Biodegradation from Heavy Crude Oil-Contaminated Soils

Comparative metagenomic analysis of PAH degradation in soil by a mixed microbial consortium.

Fungi belonging to Trichoderma genus are ascomycetes found in soils worldwide. Trichoderma has been studied in relation to diverse biotechnological applications and are known as successful colonizers of their common habitats. Members of this genus have been well described as effective biocontrol organisms through the production of secondary metabolites with potential applications as new antibiotics. Even though members of Trichoderma are commonly used for the commercial production of lytic enzymes, as a biological control agent, and also in the food industry, their use in xenobiotic biodegradation is limited. Trichoderma stands out as a genus with a great range of substrate utilization, a high production of antimicrobial compounds, and its ability for environmental opportunism. In this review, we focused on the recent advances in the research of Trichoderma species as potent and efficient aromatic hydrocarbon-degrading organisms, as well as aimed to provide insight into its potential role in the bioremediation of soils contaminated with heavy hydrocarbons. Several Trichoderma species are associated with the ability to metabolize a variety of both high and low molecular weight polycyclic aromatic hydrocarbons (PAHs) such as naphthalene, phenanthrene, chrysene, pyrene, and benzo[a]pyrene. PAH-degrading species include Trichoderma hamatum, Trichoderma harzianum, Trichoderma reesei, Trichoderma koningii, Trichoderma viride, Trichoderma virens, and Trichoderma asperellum using alternate enzyme systems commonly seen in other organisms, such as multicooper laccases, peroxidases, and ring-cleavage dioxygenases. Within these species, T. asperellum stands out as a versatile organism with remarkable degrading abilities, high tolerance, and a remarkable potential to be used as a remediation agent in polluted soils.

Biodegradation of polycyclic aromatic hydrocarbons by Trichoderma species: a mini review

Trichoderma asperellum H15, a previously isolated strain characterized by its high tolerance to low (LMW) and high molecular weight (HMW) PAHs, was tested for its ability to degrade 3-5 ring PAHs (phenanthrene, pyrene, and benzo[a]pyrene) in soil microcosms along with a biostimulation treatment with sugarcane bagasse. T. asperellum H15 rapidly adapted to PAH-contaminated soils, producing more CO2 than uncontaminated microcosms and achieving up to 78 % of phenanthrene degradation in soils contaminated with 1,000 mg Kg(-1) after 14 days. In soils contaminated with 1,000 mg Kg(-1) of a three-PAH mixture, strain H15 was shown to degrade 74 % phenanthrene, 63 % pyrene, and 81 % of benzo[a]pyrene. Fungal catechol 1,2 dioxygenase, laccase, and peroxidase enzyme activities were found to be involved in the degradation of PAHs by T. asperellum. The results demonstrated the potential of T. asperellum H15 to be used in a bioremediation process. This is the first report describing the involvement of T. asperellum in LMW and HMW-PAH degradation in soils. These findings, along with the ability to remove large amounts of PAHs in soil found in the present work provide enough evidence to consider T. asperellum as a promising and efficient PAH-degrading microorganism.

Degradation of polycyclic aromatic hydrocarbons in soil by a tolerant strain of Trichoderma asperellum

Trypanosoma cruzi is genetically classified into at least two major lineages named T cruzi I (also named Tc I) and T cruzi II (also named Tc IIb) T cruzi II is associated with Chagas' disease in the southern cone of South America, while T cruzi I is the only one so far identified in chagasic patients of Central America and in the northern part of South America Herein we identified T cruzi IIb directly in 99% of blood of chronic chagasic patients of Colombia This finding establishes that in this region, the two T cruzi lineages are associated with the pathology of Chagas' disease and have implications in the morbidity and epidemiology of the disease

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Papers

Isolation and Selection of a Highly Tolerant Microbial Consortium with Potential for PAH Biodegradation from Heavy Crude Oil-Contaminated Soils

Comparative metagenomic analysis of PAH degradation in soil by a mixed microbial consortium.

Biodegradation of polycyclic aromatic hydrocarbons by Trichoderma species: a mini review

Degradation of polycyclic aromatic hydrocarbons in soil by a tolerant strain of Trichoderma asperellum

Evidence of Trypanosoma cruzi II infection in Colombian chagasic patients.