Mycosynthesis of metal-containing nanoparticles-fungal metal resistance and mechanisms of synthesis

In the 21st century, nanomaterials play an increasingly important role in our lives with applications in many sectors, including agriculture, biomedicine, and biosensors. Over the last two decades, extensive research has been conducted to find ways to synthesise nanoparticles (NPs) via mediation with fungi or fungal extracts. Mycosynthesis can potentially be an energy-efficient, highly adjustable, environmentally benign alternative to conventional physico-chemical procedures. This review investigates the role of metal toxicity in fungi on cell growth and biochemical levels, and how their strategies of resistance, i.e., metal chelation, biomineral formation, biosorption, bioaccumulation, compartmentalisation, and efflux of metals from cells, contribute to the synthesis of metal-containing NPs used in different applications, e.g., biomedical, antimicrobial, catalytic, biosensing, and precision agriculture. The role of different synthesis conditions, including that of fungal biomolecules serving as nucleation centres or templates for NP synthesis, reducing agents, or capping agents in the synthesis process, is also discussed. The authors believe that future studies need to focus on the mechanism of NP synthesis, as well as on the influence of such conditions as pH, temperature, biomass, the concentration of the precursors, and volume of the fungal extracts on the efficiency of the mycosynthesis of NPs.Web of Science2322art. no. 1408

Mycosynthesis of metal-containing nanoparticles - Synthesis by ascomycetes and basidiomycetes and their application

Fungi contain species with a plethora of ways of adapting to life in nature. Consequently, they produce large amounts of diverse biomolecules that can be generated on a large scale and in an affordable manner. This makes fungi an attractive alternative for many biotechnological processes. Ascomycetes and basidiomycetes are the most commonly used fungi for synthesis of metal-containing nanoparticles (NPs). The advantages of NPs created by fungi include the use of non-toxic fungus-produced biochemicals, energy efficiency, ambient temperature, pressure conditions, and the ability to control and tune the crystallinity, shape, and size of the NPs. Furthermore, the presence of biomolecules might serve a dual function as agents in NP formation and also capping that can tailor the (bio)activity of subsequent NPs. This review summarizes and reviews the synthesis of different metal, metal oxide, metal sulfide, and other metal-based NPs mediated by reactive media derived from various species. The phyla ascomycetes and basidiomycetes are presented separately. Moreover, the practical application of NP mycosynthesis, particularly in the fields of biomedicine, catalysis, biosensing, mosquito control, and precision agriculture as nanofertilizers and nanopesticides, has been studied so far. Finally, an outlook is provided, and future recommendations are proposed with an emphasis on the areas where mycosynthesized NPs have greater potential than NPs synthesized using physicochemical approaches. A deeper investigation of the mechanisms of NP formation in fungi-based media is needed, as is a focus on the transfer of NP mycosynthesis from the laboratory to large-scale production and application.Web of Science241art. no. 30

Process evaluation data supporting studies on swing strategies to recover N-ethylbutylamine after wet lipid extraction from microalgae

In this paper, we publish information that has not been published before, but is needed to evaluate processes for wet lipid extraction from microalgae and recover the solvent N-ethylbutylamine (EBA), for example as presented in [1], the article entitled “Process evaluation of swing strategies to recover N-ethylbutylamine after wet lipid extraction from microalgae” in which we evaluate and interpret temperature swing and CO2-swing approaches. This includes selection of microalgae slurry concentration used in the extraction process, information on switching of EBA with CO2, data on the amount of EBA in solid residue after extraction, recoverability from the solid residue, and on recoverability of the solvent from the aqueous raffinate by liquid-liquid extraction and distillation of the solvent and EBA after the liquid-liquid extraction. Also information on phase behavior of binary mixtures of EBA and water is presented. Finally, detailed information on all flows in the process flow diagrams that are given in the article [1] is presented

Process evaluation of swing strategies to recover N-ethylbutylamine after wet lipid extraction from microalgae

N-ethylbutyl amine (EBA) has been reported as switchable solvent for the extraction of lipids from microalgae. To properly assess the technical feasibility as well as the sustainability of the lipid extraction process with EBA, solvent recovery is an essential process consideration. In this paper, opportunities for solvent recovery from both the aqueous raffinate stream and the solid algal residue were investigated, and two approaches for solvent recovery from the extracted lipids were investigated. In the first approach, CO2 switching is applied, which switches EBA from a neutral molecule into an ionic liquid that phase splits from the lipids. In the second approach, the strong effect on water solubility of EBA due to its lower critical solution temperature (LCST) behavior is used in a temperature swing back-extraction. For both approaches, a conceptual process was designed, and for all unit operations where important information was missing, the missing information was obtained by experiment and/or using process simulation software (Aspen Plus V8.8). From the conceptual process evaluation, it was concluded that the process making use of CO2 switching suffers from large solvent losses due to the switching mechanism. With the temperature swing back-extraction, it was much better possible to recover the EBA, and design a feasible process that costs 12.4 MJ/kg lipids, which considering the energy content of 1 kg lipids, is net energy gain of 22.4 MJ/kg lipids

Towards a Valorization of Corn Bioethanol Side Streams: Chemical Characterization of Post Fermentation Corn Oil and Thin Stillage

First-generation biofuel biorefineries may be a starting point for the development of new value chains, as their by-products and side streams retain nutrients and valuable molecules that may be recovered and valorized for high-value applications. This study provides a chemical characterization of post-fermentation corn oil and thin stillage, side streams of dry-grind corn bioethanol production, in view of their valorization. An overall long-term study was conducted on the two co-products collected over 1 year from a bioethanol plant. Water content, acid value, sedimentation, mineral composition, and fatty acid profiles were analyzed on post-fermentation corn oil. Results highlighted that its acid value was high (19.72–24.29 mg KOH/g), indicating high levels of free fatty acids, but stable over the year due to standardized operating conditions. The fatty acid profile was that typical of corn oil, with a prevalence of linoleic (54–59% of total fatty acids) over oleic (23–27%) and palmitic (12–17%) acids. Macronutrients, fatty acid, and mineral profiles were investigated in thin stillage. Results revealed the acidic pH (4.05–4.68) and high dilution (90–93% water) of this side stream. The dry mass was composed of fats (19–30%), proteins (8.8–12.8%), ash (8.7–9.5%), and fiber (7.3–9.8%). The concomitant presence of a variegate complex of molecules of nutritional interest in corn bioethanol co-products, with several potential high-value market applications, make the perspective of their recovery a promising strategy to create new cross-sector interconnections according to circular economy principles