Amazonian soil fungi are efficient degraders of glyphosate herbicide; novel isolates of Penicillium, Aspergillus, and Trichoderma

Pesticide residues that contaminate the environment circulate within the hydrological cycle can accumulate within the food chain and cause problems to both environmental and human health. Microbes, however, are well known for their metabolic versatility and the ability to degrade chemically stable substances, including recalcitrant xenobiotics. The current study focused on bio-prospecting within Amazonian rainforest soils to find novel strains fungi capable of efficiently degrading the agriculturally and environmentally ubiquitous herbicide, glyphosate. Of 50 fungal strains isolated (using culture media supplemented with glyphosate as the sole carbon-substrate), the majority were Penicillium strains (60%) and the others were Aspergillus and Trichoderma strains (26 and 8%, respectively). All 50 fungal isolates could use glyphosate as a phosphorous source. Eight of these isolates grew better on glyphosate-supplemented media than on regular Czapek Dox medium. LC-MS revealed that glyphosate degradation by Penicillium 4A21 resulted in sarcosine and aminomethylphosphonic acid.

Comparison of the Responses of Soil Fungal Community to Straw, Inorganic Fertilizer, and Compost in a Farmland in the Loess Plateau

Determining the response of soil fungi in sensitive ecosystems to external environmental disturbances is an important, yet little-known, topic in microbial ecology. In this study, we evaluated the impact of traditional fertilization management practices on the composition, co-occurrence pattern, and functional groups of fungal communities in loessial soil.

Spatial Distribution and Influencing Factors of Soil Fungi in a Degraded Alpine Meadow Invaded by Stellera chamaejasme

Alpine meadow degradation causes a notable decrease in palatable grasses and an increase in forbs and toxic plants in recent decades. Stellera chamaejasme is one of the most serious toxic weeds, which exerts an increasing threat on alpine meadow in Qinghai–Tibetan Plateau. Combined DNA sequencing with geostatistics was applied to analyze a typical degraded meadow invaded by S. chamaejasme in Qinghai Province, China. The study aimed to determine the spatial variation of soil fungi and its interrelationship with the plant–soil environment. Alpha diversity and relative abundance of fungal phyla and classes showed moderate or strong spatial dependency and were structured in patches of 19–318 m, and taxonomic composition exhibited much higher spatial variability than alpha diversity. Compared to plant cover, the matching of patch size showed a closer spatial link between soil properties and fungal community. Community coverage, SOM, TN, TP, and TK positively correlated to fungal diversity and taxonomic composition; no direct correlation was found between S. chamaejasme coverage and fungal community. The result suggested significant but weak association between plant–soil properties and soil fungal community at local scale. Patchy pattern of S. chamaejasme may disturb spatial variations of soil properties and fungal community, since S. chamaejasme in higher coverage corresponded to lower TK content, which contributed to a decrease in fungal diversity indirectly.

Production of biosurfactants using Egyptian soil fungi

Soil fungi have unique physiological and metabolic features, and are considered as an important source of biomolecules. The present research aims to study the ability of local soil fungal isolates for the production of biosurfactants and to study the stability of these biosurfactants under different temperatures (50, 70, 90, 110, and 121 ºC), different pH values (2, 3, 6, 10, 12, and 15), and different salinity concentrations (5, 10, 15, 20, and 25% NaCl) depending on the formation of clear zone using oil displacement area (ODA) test. The research also aims to study the enhancement effect of four vegetable oils including sunflower oil, waste frying oil, olive oil, and corn oil on the activity of the produced biosurfactants. The obtained results showed that Aspergillus flavus, Aspergillus wentii and Fusarium sp. had the maximum biosurfactants production. The stability of biosurfactants occurred at alkaline pH, wide range of temperatures, and under high salinity (15%). Sunflower oil had the maximum enhancement effect on the activity of the produced biosurfactants, while corn oil showed lower enhancement effect. Depending on the obtained results, it can be concluded that local soil fungal isolates are considered as a promising source for production of biosurfactants.