Fungal bio-sorption potential of chromium in Norkrans liquid medium by shake flask technique

Metagenomics: A Tool for Exploring Key Microbiome With the Potentials for Improving Sustainable Agriculture

Microorganisms are immense in nature and exist in every imaginable ecological niche, performing a wide range of metabolic processes. Unfortunately, using traditional microbiological methods, most microorganisms remain unculturable. The emergence of metagenomics has resolved the challenge of capturing the entire microbial community in an environmental sample by enabling the analysis of whole genomes without requiring culturing. Metagenomics as a non-culture approach encompasses a greater amount of genetic information than traditional approaches. The plant root-associated microbial community is essential for plant growth and development, hence the interactions between microorganisms, soil, and plants is essential to understand and improve crop yields in rural and urban agriculture. Although some of these microorganisms are currently unculturable in the laboratory, metagenomic techniques may nevertheless be used to identify the microorganisms and their functional traits. A detailed understanding of these organisms and their interactions should facilitate an improvement of plant growth and sustainable crop production in soil and soilless agriculture. Therefore, the objective of this review is to provide insights into metagenomic techniques to study plant root-associated microbiota and microbial ecology. In addition, the different DNA-based techniques and their role in elaborating plant microbiomes are discussed. As an understanding of these microorganisms and their biotechnological potentials are unlocked through metagenomics, they can be used to develop new, useful and unique bio-fertilizers and bio-pesticides that are not harmful to the environment.

Iron stress response and bioaccumulation potential of three fungal strains isolated from sewage-irrigated soil

AIMS

Contamination with heavy metal (HM) is a severe environmental issue. Therefore, there is a pressing need to create environmentally safe and cost-effective HM bioremediation approaches.

METHODS AND RESULTS

Three iron-tolerant fungal strains were isolated from sewage-irrigated soils, molecularly identified and deposited in the GenBank as Aspergillus flavus MT639638, A. terreus MT605370 and Fusarium oxysporum MT605399. The fungal growth, minimum inhibitory concentration (MIC), tolerance index (TI), removal efficiency, bioaccumulation, and enzymatic and non-enzymatic antioxidants were determined. Based on MIC values, A. flavus MT639638 was the most resistant strain. F. oxysporum displayed the highest percent removal efficiency (93.65% at 4000 mg L^-1 ) followed by A. flavus (92.92%, at 11,000 mg L^-1 ), and A. terreus (91.18% at 3000 mg L^-1 ). F. oxysporum was selected based on its highly sensitivity for further characterization of its response to Fe(II) stress using TEM, SEM and EDX, in addition to HPLC analysis of organic acids. These analyses demonstrated the localization of bioaccumulated Fe(II) and ultrastructural changes induced by iron and indicated induction release of organic acids.

CONCLUSIONS

Our fungal strains showed an effective capacity for removal of Fe(II) via bioaccumulation and biosorption mechanisms which were supported by instrumental analyses. The iron tolerance potentiality was mediated by induction of selected antioxidative enzymes and biomolecules.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study depicts a potential utilization of the three fungal strains for the bioremediation of iron-contaminated soils.

Climatic and Socioeconomic Aspects of Mushrooms: The Case of Spain

Fungi are some of the most diverse organisms on earth and since prehistoric times have played an important role in human society. In recent years they have become a strategic asset not only in the conservation and management of ecosystems but also as a resource for halting the exodus from rural areas in peripheral Mediterranean regions, such as inland eastern Spain. In view of this important ecological and socioeconomic role, in this paper we present a geographical analysis of edible fungi, paying particular attention to the Spanish case. To this end we carried out a bibliographic review of the climatic factors affecting the fruiting of these fungi and the socioeconomic aspects of their commercial exploitation. We also performed an online search for mycotourism-related activities and explored the statistical data on the cultivation of edible mushrooms and its economic impact. Our main findings include a synthesis of the international research on the effects of climatic variability on the natural production of macrofungi, and an assessment of the economic viability and the social importance of mushrooms in Spain, in particular in relation to the current and future potential of mushroom cultivation and the multifunctional management and use of forests.