Federico Rossi

Università di Pisa | UNIPI

Our planet teeters on the brink of massive ecosystem collapses, and arid regions experience manifold environmental and climatic challenges that increase the magnitude of selective pressures on already stressed ecosystems. Ultimately, this leads to their aridification and desertification, that is, to simplified and barren ecosystems (with proportion...

Background In hot deserts daily/seasonal fluctuations pose great challenges to the resident organisms. However, these extreme ecosystems host unique microenvironments, such as the rhizosheath–root system of desert speargrasses in which biological activities and interactions are facilitated by milder conditions and reduced fluctuations. Here, we exa...

The use of cyanobacteria as soil inoculants is a very promising biotechnological approach that is receiving increasing scientific attention for its potential for soil degradation control. Inoculation of selected cyanobacterial strains has shown the ability to significantly improve the physicochemical properties of degrading soils in different envir...

The effects of natural compounds on biofilm formation have been extensively studied, with the goal of identifying biofilm formation antagonists at sub-lethal concentrations. Salicylic and cinnamic acids are some examples of these compounds that interact with the quinone oxidoreductase WrbA, a potential biofilm modulator and an antibiofilm compound...

The induction of biocrusts through inoculation-based techniques has gained increasing scientific attention in the last 2 decades due to its potential to address issues related to soil degradation and desertification. The technology has shown the most rapid advances in the use of biocrust organisms, particularly cyanobacteria and mosses, as inoculan...

Aim: Microbial diversity is one of the most important factors for maintaining the performance of multiple functions in soils (multifunctionality). However, existing studies typically consider the taxonomic richness or Shannon diversity of the entire community. We know little about the connection network of taxonomic and phylogenetic facets of dive...

The acquisition of a biofilm lifestyle is common in nature for microorganisms. It increases biotic and abiotic stress tolerance of microorganisms and is functional to provide ecosystem services. Although diminutive communities, soil beneficial biofilms are essential for nutrient cycling, soil stabilization, and direct or indirect promotion of plant...

Biocrusts can be found in a wide array of habitats, where they provide important ecosystem services. These microbial associations are particularly important in High Arctic environments, where biocrust colonize the newly exposed barren soil after glacier retreat and significantly contribute to soil stabilization and nutrient cycling. Starting from i...

Dear Colleagues, Continuous soil and water contamination with compounds such as polychlorinated biphenils, polycyclic aromatic hydrocarbons, radionuclides, pharmaceutical substances, and metals represents a serious threat. These can affect humans and animals by disrupting their endocrine systems, with deleterious effects on the environment. Microb...

What kinds of single indicators are appropriate, when we calculate multifunctionality?

s Microbial diversity is one of the most important drivers on ecosystem to maintain the simultaneous performance of functions (multifunctionality, MF) under climatic oscillation. However, existing studies typically consider taxonomic richness or Shannon index at the community level in which relations between diversity and functioning are not highly...

Supplementary information

Cyanobacteria are widespread prokaryotic organisms that represent feasible biotechnological tools to set up valid approaches to counteract desertification. Their peculiar physiological traits, and their resilience to abiotic stresses, allow their application on abiotically constrained soils to trigger their stabilization. A successful cya-nobacteri...

Many cyanobacteria produce extracellular polymeric substances (EPS) mainly composed of heteropolysaccharides with unique characteristics that make them suitable for biotechnological applications. However, manipulation/optimization of EPS biosynthesis/characteristics is hindered by a poor understanding of the production pathways and the differences...

Cyanobacterial alternative sigma factors are crucial players in environmental adaptation processes, which may involve bacterial responses related to maintenance of cell envelope and control of secretion pathways. Here, we show that the Group 3 alternative sigma factor F (SigF) plays a pleiotropic role in Synechocystis sp. PCC 6803 physiology, with...

Background Extracellular polymeric matrix (EPM) is a complex component of the organo-mineral assemblages created by biological soil crusts (BSCs). Mainly of polysaccharidic origin, it embeds soil and sediments and provides key benefits to the crust community. Services provided include: sediment cohesion and resistance to erosion, moisture provision...

Aims Biological soil crusts (biocrusts) are microbial communities commonly found in the upper layer of arid soils. These microorganisms release exopolysaccharides (EPS), which form the exopolymeric matrix (EPM), allowing them to bond soil particles together and survive long periods of dryness. The aim of this work is to develop methods for measurin...

Soil inoculation with cyanobacteria to promote the formation of biocrusts is considered a potential eco-friendly method to counteract desertification spread in drylands. Research is needed to increase the number of proficient cyanobacterial strains, selected for their capability to survive in harsh conditions and to form stable biocrusts quickly. W...

Cyanobacteria are ubiquitous components of biocrust communities and the first colonizers of terrestrial ecosystems. They play multiple roles in the soil by fixing C and N and synthesizing exopolysaccharides, which increase soil fertility and water retention and improve soil structure and stability. Application of cyanobacteria as inoculants to prom...

Soil inoculation with cyanobacteria (cyanobacterization) is a biotechnological method widely studied to improve soil quality and productivity. During their growth on soil, cyanobacteria excrete exopolysaccharides (EPSs) which glue trichomes to soil particles, in a three-dimensional extracellular polymeric matrix. EPS productivity is an important sc...

The use of cyanobacteria as soil inoculants (cyanobacterization) has been widely studied as a mean to improve soil fertility and crop yields, albeit intermittently, for the last 60 years (Hamdi 1982). More recently, cyanobacterization was also studied as a biotechnological approach to stabilize and fertilize desert soils, counteracting desertificat...

The main crude polysaccharides (CPS), extracted from two widely cultivated pomegranate varieties, Laffan and Wonderful, were studied and characterized. We obtained the highest CPS extraction yield (approximatively 10% w/w on dried matter) by 1 h of decoction (ratio 1/40 w/v). The predominant polymers (75-80%) of the CPS samples shown a hydrodynamic...

The use of cyanobacteria as soil improvers and bio-conditioners (a technique often referred to as algalization) has been studied for decades. Several studies proved that cyanobacteria are feasible eco-friendly candidates to trigger soil fertilization and enrichment from agricultural to arid and hyper-arid systems. This approach can be successful to...

Biological soil crusts (biocrusts) are considered key players in hydrological cycles of many arid environments. The phototrophic organisms in these crusts excrete extracellular polymeric substances (EPSs), which bind soil particles together, thereby stabilizing the soil surface. In a previous work, the noninvasive extraction of EPSs in biocrusts re...

Cyanobacteria are feasible eco-friendly candidates to trigger soil improvement and enrichment. According to several studies, cyanobacteria could be employed as inoculants in different contexts, from agricultural to arid and hyper-arid systems. Successful soil inoculation with cyanobacteria leads to the development of cyanobacterial crusts, which ar...

Bioremediation of heavy metals using microorganisms can be advantageous compared to conventional physicochemical methods due to the use of renewable resources and efficiencies of removal particularly cations at low concentrations. In this context, cyanobacteria/cyanobacterial extracellular polymeric substances (EPS) emerge as a valid alternative du...

While the beneficial effects of algalization to improve agricultural fields are well known, a limited number of inoculation studies have been so far carried out in prohibitive constrained ecosystems, where soil is unconsolidated, with very limited nutrient levels and high abiotic stress levels. Recent results show that some cyanobacterial strains s...

Extracellular polysaccharides (EPSs) produced by microalgae and cyanobacteria are molecules with a great ecological significance for the producing organisms, serving in a wide array of biological processes and increasing the organism tolerance to environmental stresses. In addition, due to their distinctive chemical, rheological properties and the...

Hydrogen represents a possible alternative energy carrier to face the growing request for energy and the shortage of fossil fuels. Photofermentation for the production of H2 constitutes a promising way for integrating the production of energy with waste treatments. Many wastes are characterized by high salinity, and polluted seawater can as well be...

The progression of desertification is well recognised as an increasing environmental, so cial and economic emergency existing on all the continents. Desertification has been defined as “land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors, including climate variation and human activity”. In order to remediate d...

Israel Microcystis spp. is a cyanobacterial species that commonly forms blooms in euthrophic lakes and grows in colonial forms. There are environmental, ecological and health concerns regarding the expansion of these bio-formations, since they determine water quality deterioration, generate anoxia and alter existing food webs. In addition, toxin se...

To date the effectiveness of antibiotics is undermined by microbial resistance, threatening public health worldwide. Enhancing the efficacy of the current antibiotic arsenal is an alternative strategy. The administration of antimicrobials encapsulated in nanocarriers, such as liposomes, is considered a viable option, though with some drawbacks rela...

Biological soil crusts (BSCs) play important roles in the hydrological cycles of many different ecosystems around the world. In arid and semi-arid regions, they alter the availability and redistribution of water. Especially in early successional stage BSCs, this feature can be attributed to the presence and characteristics of extracellular polymeri...

Biological Soil Crusts (BSCs) are associations between soil particles and varying proportions of cyanobacteria, heterotrophic bacteria, algae, fungi, lichens and mosses. BSCs play a major role in soil stabilization, and in drylands have been well acknowledged for mitigating desertification effects. Amongst the wide diversity of organisms that compo...

Biological soil crusts (BSCs) are highly specialized topsoil microbial communities widespread in many ecosystems, from deserts to polar regions. BSCs play an active role in promoting soil fertility and plant growth. In Arctic environments BSCs are involved in promoting primary succession after deglaciation, increasing moisture availability and nutr...

Exopolysaccharides (EPSs) are an important class of biopolymers with great ecological importance. In natural environments, they are a common feature of microbial biofilms, where they play key protective and structural roles. As the primary colonizers of constrained environments, such as desert soils and lithic and exposed substrates, cyanobacteria...

The growing concern for the increase of the global warming effects due to anthropogenic activities raises the challenge of finding novel technological approaches to stabilize CO2 emissions in the atmosphere and counteract impinging interconnected issues such as desertification and loss of biodiversity.Biological-CO2 mitigation, triggered through bi...

In this study, the chemical composition and the macromolecular features of the extracellular polysaccharidic (EPS) matrix of induced biological soil crusts (IBSCs) of dif- ferent age, collected in the hyper-arid plateau of Hobq desert, Inner Mongolia, China, were investigated. Any statistically significant correlation between the amount of extracel...

Two-stage process based on photofermentation of dark fermentation effluents is widely recognized as the most effective method for biological production of hydrogen from organic substrates. Recently, it was described an alternative mechanism, named capnophilic lactic fermentation, for sugar fermentation by the hyperthermophilic bacterium Thermotoga...

The development of Biological Soil Crusts (BSCs) is widely recognized as beneficial to soil fertility due to their contribution to the stabilization of soils and to the increase in their carbon and moisture content. An important role in these processes is played by the extracellular polysaccharidic (EPS) matrix embedding microbial cells and soil pa...

Hydrogen is a clean fuel. Its combustion produces just water and energy. The opportunity of obtaining renewable energy from vegetable residues largely available makes microbiological processes an interesting perspective. Aim of this research activity was to evaluate the possibility of inserting the photofermentative hydrogen producing process after...

The accumulation of heavy metals in water bodies represent a widespread cause of pollution, and poses the need to develop novel technologies to remove metals at the source, abating the costs of the commonly used chemical and physio-chemical methods. The use of cyanobacteria as biosorbents has been acknowledged as a promising alternative, due to the...

The molecular identification of seven biofilmforming cyanobacteria and the characterization of their exopolysaccharides were made and considered in terms of potential biotechnological applications. The studied strains were isolated from phototrophic biofilms taken from various Italian sites including a wastewater treatment plant, an eroded soil, an...

The supportive and negative evidence for the stress gradient hypothesis (SGH) led to an ongoing debate among ecologists and called for new empirical and theoretical work. In this study, we took various biological soil crust (BSCs) samples along a spatial gradient with four environmental stress levels to examine the fitness of SGH in microbial inter...

Many cyanobacterial strains can synthesize and secrete extracellular polymeric substances (EPS) that can remain associated to the cell or be released into the surrounding environment (RPS-released polysaccharides). The particular characteristics of the cyanobacterial EPS, namely the presence of 2 different uronic acids, sulphate groups and high num...

The importance of cyanobacterial polysaccharides of biological soil crusts in sand surface stabilization and soil nutrient retention has been long acknowledged. However, the role of cyanobacterial polysaccharides as a source of nutrition to vascular plants in crusted areas is ignored. In this study, the chemical composition of the polysaccharide sy...

Biological soil crusts (BSC) are soil-surface communities that represent a typical example of microbial adaptability to harsh environmental conditions. They improve soil fertility and promote plant growth, representing a valid putative tool to fight desertification processes. Various mechanisms allow them to withstand constraints such as drought,...

Biological soil crusts (BSCs) are highly specialized topsoil microbial communities commonly found in arid and semiarid environments, permeated by a polymeric matrix of polysaccharides. BSCs can in principle influence edaphic properties such as texture, pore formation and water retention, which in turn determine water distribution and biological act...

Three coccoid and two filamentous cyanobacterial strains were isolated from phototrophic biofilms exposed to intense solar radiation on lithic surfaces of the Parasurameswar Temple and Khandagiri caves, located in Orissa State, India. Based on to their morphological features, the three coccoid strains were assigned to the genera Gloeocapsosis and G...

Many cyanobacterial strains can synthesize and secrete extracellular polymeric substances (EPS) that can remain associated to the cell or be released into the surrounding environment (RPS-released polysaccharides). The particular characteristics of these EPS, namely the presence of 2 different uronic acids, sulphate groups and high number of differ...