Biosynthesis of cadmium sulphide quantum dots by usingPleurotus ostreatus(Jacq.) P. Kumm

A review on mycogenic metallic nanoparticles and their potential role as antioxidant, antibiofilm and quorum quenching agents

The emergence of antimicrobial resistance among biofilm forming pathogens aimed to search for the efficient and novel alternative strategies. Metallic nanoparticles have drawn a considerable attention because of their significant applications in various fields. Numerous methods are developed for the generation of these nanoparticles however, mycogenic (fungal-mediated) synthesis is attractive due to high yields, easier handling, eco-friendly and being energy efficient when compared with conventional physico-chemical methods. Moreover, mycogenic synthesis provides fungal derived biomolecules that coat the nanoparticles thus improving their stability. The process of mycogenic synthesis can be extracellular or intracellular depending on the fungal genera used and various factors such as temperature, pH, biomass concentration and cultivation time may influence the synthesis process. This review focuses on the synthesis of metallic nanoparticles by using fungal mycelium, mechanism of synthesis, factors affecting the mycosynthesis and also describes their potential applications as antioxidants and antibiofilm agents. Moreover, the utilization of mycogenic nanoparticles as quorum quenching agent in hampering the bacterial cell-cell communication (quorum sensing) has also been discussed.

Strain-specific features of Pleurotus ostreatus growth in vitro and some of its biological activities

BACKGROUND

The production of Pleurotus ostreatus mycelium as a promising object for use in food and other industries is hampered by a lack of information about the strain-specificity of this fungus mycelium growth and its acquisition of various biological activities. Therefore, this research aimed to investigate mycelial growth of different P. ostreatus strains on varies solid and liquid media as well as to evaluate strains antagonistic, antibacterial, antiradical scavenging activities, and total phenolic content.

RESULTS

Potato Dextrose Agar medium was suitable for all strains except P. ostreatus strain 2460. The best growth rate of P. ostreatus 2462 strain on solid culture media was 15.0 ± 0.8 mm/day, and mycelia best growth on liquid culture media-36.5 ± 0.2 g/l. P. ostreatus strains 551 and 1685 were more susceptible to positive effect of plant growth regulators Ivin, Methyur and Kamethur. Using of nutrient media based on combination of natural waste (amaranth flour cake and wheat germ, wheat bran, broken vermicelli and crumbs) has been increased the yield of P. ostreatus strains mycelium by 2.2-2.9 times compared to the control. All used P. ostreatus strains displayed strong antagonistic activity in co-cultivation with Aspergillus niger, Candida albicans, Issatchenkia orientalis, Fusarium poae, Microdochium nivale in dual-culture assay. P. ostreatus 2462 EtOAc mycelial extract good inhibited growth of Escherichia coli (17.0 ± 0.9 mm) while P. ostreatus 2460 suppressed Staphylococcus aureus growth (21.5 ± 0.5 mm) by agar well diffusion method. The highest radical scavenging effect displayed both mycelial extracts (EtOH and EtOAc) of P. ostreatus 1685 (61 and 56%) by DPPH assay as well as high phenolic content (7.17 and 6.73 mg GAE/g) by the Folin-Ciocalteu's method. The maximal total phenol content (7.52 mg GAE/g) demonstrated of P. ostreatus 2461 EtOH extract.

CONCLUSIONS

It is found that the growth, antibacterial, antiradical scavenging activity as well as total phenolic content were dependent on studied P. ostreatus strains in contrast to antagonistic activity. The proposed culture mediums of natural waste could be an alternative to commercial mediums for the production mycelial biomass of P. ostreatus strains.

Biosynthesis of Quantum Dots and Their Therapeutic Applications in the Diagnosis and Treatment of Cancer and SARS-CoV-2

Quantum dots (QDs) are semiconductor materials that range from 2 nm to 10 nm. These nanomaterials (NMs) are smaller and have more unique properties compared to conventional nanoparticles (NPs). One of the unique properties of QDs is their special optoelectronic properties, making it possible to apply these NMs in bioimaging. Different size and shape QDs, which are used in various fields such as bioimaging, biosensing, cancer therapy, and drug delivery, have so far been produced by chemical methods. However, chemical synthesis provides expensive routes and causes serious environmental and health issues. Therefore, various biological systems such as bacteria, fungi, yeasts, algae, and plants are considered as potent eco-friendly green nanofactories for the biosynthesis of QDs, which are both economic and environmentally safe. The review aims to provide a descriptive overview of the various microbial agents for the synthesis of QDs and their biomedical applications for the diagnosis and treatment of cancer and SARS-CoV-2.

Diversity of Mycogenic Oxide and Chalcogenide Nanoparticles: A Review

Oxide and chalcogenide nanoparticles have great potential for use in biomedicine, engineering, agriculture, environmental protection, and other research fields. The myco-synthesis of nanoparticles with fungal cultures, their metabolites, culture liquids, and mycelial and fruit body extracts is simple, cheap and environmentally friendly. The characteristics of nanoparticles, including their size, shape, homogeneity, stability, physical properties and biological activity, can be tuned by changing the myco-synthesis conditions. This review summarizes the data on the diversity of oxide and chalcogenide nanoparticles produced by various fungal species under different experimental conditions.

Eco-Friendly Intracellular Biosynthesis of CdS Quantum Dots Using Pseudomonas aeruginosa: Evaluation of Antimicrobial Effects and DNA Cleavage Activities

BACKGROUND

Intracellular biosynthesis of Quantum Dots (QDs) based on microorganisms offers a green alternative and eco-friendly for the production of nanocrystals with superior properties. This study focused on the production of intracellular CdS QDs by stimulating the detoxification metabolism of Pseudomonas aeruginosa.

METHODS

For this aim, Pseudomonas aeruginosa ATCC 27853 strain was incubated in a solution of 1mM cadmium sulphate (CdSO4) to manipulate the detoxification mechanism. The intracellularly formed Cd-based material was extracted, and its characterization was carried out by Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD), Energy Dispersive X-ray (EDX) and dynamic light scattering (DLS) analyses and absorption-emission spectra.

RESULTS

The obtained material showed absorption peaks at 385 nm and a luminescence peak at 411 nm, and the particle sizes were measured in the range 4.63-17.54 nm. It was determined that the material was sphere-shaped, with a cubic crystalline structure, including Cd and S elements. The antibacterial and antifungal activities of CdS QDs against patent eleven bacterial (four Grampositive and seven Gram-negative) and one fungal strains were investigated by the agar disk diffusion method. It was revealed that the obtained material has antibacterial effects on both Grampositive and Gram-negative bacteria. However, cleavage activity of CdS QDs on pBR322 DNA was not detected.

CONCLUSION

As a result, it has been proposed that the stimulation of the detoxification mechanism can be an easy and effective way of producing green and cheap luminescent QDs or nanomaterial.

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.

Bioresource-Functionalized Quantum Dots for Energy Generation and Storage: Recent Advances and Feature Perspective

The exponential increase in global energy demand in daily life prompts us to search for a bioresource for energy production and storage. Therefore, in developing countries with large populations, there is a need for alternative energy resources to compensate for the energy deficit in an environmentally friendly way and to be independent in their energy demands. The objective of this review article is to compile and evaluate the progress in the development of quantum dots (QDs) for energy generation and storage. Therefore, this article discusses the energy scenario by presenting the basic concepts and advances of various solar cells, providing an overview of energy storage systems (supercapacitors and batteries), and highlighting the research progress to date and future opportunities. This exploratory study will examine the systematic and sequential advances in all three generations of solar cells, namely perovskite solar cells, dye-sensitized solar cells, Si cells, and thin-film solar cells. The discussion will focus on the development of novel QDs that are economical, efficient, and stable. In addition, the current status of high-performance devices for each technology will be discussed in detail. Finally, the prospects, opportunities for improvement, and future trends in the development of cost-effective and efficient QDs for solar cells and storage from biological resources will be highlighted.

Biosustainable production of nanoparticles via mycogenesis for biotechnological applications: A critical review

The demand for the green synthesis of nanoparticles has gained prominence over the conventional chemical and physical syntheses, which often entails toxic chemicals, energy consumption and ultimately lead to negative environmental impact. In the green synthesis approach, naturally available bio-compounds found in plants and fungi can be effective and have been proven to be alternative reducing agents. Fungi or mushrooms are particularly interesting due to their high content of bioactive compounds, which can serve as excellent reducing agents in the synthesis of nanoparticles. Apart from the economic and environmental benefits, such as ease of availability, low synthesis/production cost, safe and no toxicity, the nanoparticles synthesized from this green method have unique physical and chemical properties. Stabilisation of the nanoparticles in an aqueous solution is exceedingly high, even after prolonged storage with unperturbed size uniformity. Biological properties were significantly improved with higher biocompatibility, anti-microbial, anti-oxidant and anti-cancer properties. These remarkable properties allow further exploration in their applications both in the medical and agricultural fields. This review aims to explore the mushroom-mediated biosynthesis of nanomaterials, specifically the mechanism and bio-compounds involved in the synthesis and their interactions for the stabilisation of nanoparticles. Various metal and non-metal nanoparticles have been discussed along with their synthesis techniques and parameters, making them ideal for specific industrial, agricultural, and medical applications. Only recent developments have been explored in this review.

Biogenic Sulfur-Based Chalcogenide Nanocrystals: Methods of Fabrication, Mechanistic Aspects, and Bio-Applications

Bio-nanotechnology has emerged as an efficient and competitive methodology for the production of added-value nanomaterials (NMs). This review article gathers knowledge gleaned from the literature regarding the biosynthesis of sulfur-based chalcogenide nanoparticles (S-NPs), such as CdS, ZnS and PbS NPs, using various biological resources, namely bacteria, fungi including yeast, algae, plant extracts, single biomolecules, and viruses. In addition, this work sheds light onto the hypothetical mechanistic aspects, and discusses the impact of varying the experimental parameters, such as the employed bio-entity, time, pH, and biomass concentration, on the obtained S-NPs and, consequently, on their properties. Furthermore, various bio-applications of these NMs are described. Finally, key elements regarding the whole process are summed up and some hints are provided to overcome encountered bottlenecks towards the improved and scalable production of biogenic S-NPs.

Synthesis, Properties and Bioimaging Applications of Silver-Based Quantum Dots

Ag-based quantum dots (QDs) are semiconductor nanomaterials with exclusive electrooptical properties ideally adaptable for various biotechnological, chemical, and medical applications. Silver-based semiconductor nanocrystals have developed rapidly over the past decades. They have become a promising luminescent functional material for in vivo and in vitro fluorescent studies due to their ability to emit at the near-infrared (NIR) wavelength. In this review, we discuss the basic features of Ag-based QDs, the current status of classic (chemical) and novel methods ("green" synthesis) used to produce these QDs. Additionally, the advantages of using such organisms as bacteria, actinomycetes, fungi, algae, and plants for silver-based QDs biosynthesis have been discussed. The application of silver-based QDs as fluorophores for bioimaging application due to their fluorescence intensity, high quantum yield, fluorescent stability, and resistance to photobleaching has also been reviewed.

Mycoremediation of heavy metals: processes, mechanisms, and affecting factors

Industrial processes and mining of coal and metal ores are generating a number of threats by polluting natural water bodies. Contamination of heavy metals (HMs) in water and soil is the most serious problem caused by industrial and mining processes and other anthropogenic activities. The available literature suggests that existing conventional technologies are costly and generated hazardous waste that necessitates disposal. So, there is a need for cheap and green approaches for the treatment of such contaminated wastewater. Bioremediation is considered a sustainable way where fungi seem to be good bioremediation agents to treat HM-polluted wastewater. Fungi have high adsorption and accumulation capacity of HMs and can be potentially utilized. The most important biomechanisms which are involved in HM tolerance and removal by fungi are bioaccumulation, bioadsorption, biosynthesis, biomineralisation, bioreduction, bio-oxidation, extracellular precipitation, intracellular precipitation, surface sorption, etc. which vary from species to species. However, the time, pH, temperature, concentration of HMs, the dose of fungal biomass, and shaking rate are the most influencing factors that affect the bioremediation of HMs and vary with characteristics of the fungi and nature of the HMs. In this review, we have discussed the application of fungi, involved tolerance and removal strategies in fungi, and factors affecting the removal of HMs.

Biosynthesized Quantum Dots as Improved Biocompatible Tools for Biomedical Applications

Quantum Dots (QDs), whose diameters are often limited to 10 nm, have been of interest to researchers for their unique optical characteristics, which are attributed to quantum confinement. Following their early application in the electrical industry as light-emitting diode materials, semiconductor nanocrystals have continued to show great potential in clinical diagnosis and biomedical applications. The conventional physical and chemical pathways for QD syntheses typically require harsh conditions and hazardous reagents, and these products encounter non-hydrophilic problems due to organic capping ligands when they enter the physiological environment. The natural reducing abilities of living organisms, especially microbes, are then exploited to prepare QDs from available metal precursors. Low-cost and eco-friendly biosynthesis approaches have the potential for further biomedical applications which benefit from the good biocompatibility of protein-coated QDs. The surface biomass offers many binding sites to modify substances or target ligands, therefore achieving multiple functions through simple and efficient operations. Biosynthetic QDs could function as bioimaging and biolabeling agents because of their luminescence properties similar to those of chemical QDs. In addition, extensive research has been carried out on the antibacterial activity, metal ion detection and bioremediation. As a result, this review details the advanced progress of biomedical applications of biosynthesized QDs and illustrates these principles as clearly as possible.

Pleurotus Macrofungi-Assisted Nanoparticle Synthesis and Its Potential Applications: A Review

Research and innovation in nanoparticles (NPs) synthesis derived from biomaterials have gained much attention due to their unique characteristics, such as low-cost, easy synthesis methods, high water solubility, and eco-friendly nature. NPs derived from macrofungi, including various mushroom species, such as Agaricus bisporus, Pleurotus spp., Lentinus spp., and Ganoderma spp. are well known to possess high nutritional, immune-modulatory, antimicrobial (antibacterial, antifungal and antiviral), antioxidant, and anticancerous properties. Fungi have intracellular metal uptake ability and maximum wall binding capacity; because of which, they have high metal tolerance and bioaccumulation ability. Primarily, two methods have been comprehended in the literature to synthesize metal NPs from macrofungi, i.e., the intracellular method, which refers to NP synthesis inside fungal cells by transportation of ions in the presence of enzymes; and the extracellular method, which refers to the treatment of fungal biomolecules aqueous filtrate with a metal precursor. Pleurotus derived metal NPs are known to inhibit the growth of numerous foodborne pathogenic bacteria and fungi. To the best of our knowledge, there is no such review article reported in the literature describing the synthesis and complete application and mechanism of NPs derived from macrofungi. Herein, we intend to summarize the progressive research on macrofungi derived NPs regarding their synthesis as well as applications in the area of antimicrobial (antibacterial & antifungal), anticancer, antioxidant, catalytic and food preservation. Additionally, the challenges associated with NPs synthesis will also be discussed.

Superior Properties and Biomedical Applications of Microorganism-Derived Fluorescent Quantum Dots

Quantum dots (QDs) are fluorescent nanocrystals with superb photo-physical properties. Applications of QDs have been exponentially increased during the past decade. They can be employed in several disciplines, including biological, optical, biomedical, engineering, and energy applications. This review highlights the structural composition and distinctive features of QDs, such as resistance to photo-bleaching, wide range of excitations, and size-dependent light emission features. Physical and chemical preparation of QDs have prominent downsides, including high costs, regeneration of hazardous byproducts, and use of external noxious chemicals for capping and stabilization purposes. To eliminate the demerits of these methods, an emphasis on the latest progress of microbial synthesis of QDs by bacteria, yeast, and fungi is introduced. Some of the biomedical applications of QDs are overviewed as well, such as tumor and microRNA detection, drug delivery, photodynamic therapy, and microbial labeling. Challenges facing the microbial fabrication of QDs are discussed with the future prospects to fully maximize the yield of QDs by elucidating the key enzymes intermediating the nucleation and growth of QDs. Exploration of the distribution and mode of action of QDs is required to promote their biomedical applications.

Synthesis, Properties, and Biological Applications of Metallic Alloy Nanoparticles

Metallic alloy nanoparticles are synthesized by combining two or more different metals. Bimetallic or trimetallic nanoparticles are considered more effective than monometallic nanoparticles because of their synergistic characteristics. In this review, we outline the structure, synthesis method, properties, and biological applications of metallic alloy nanoparticles based on their plasmonic, catalytic, and magnetic characteristics.

Anticancer and Antibacterial Activity of Cadmium Sulfide Nanoparticles byAspergillus niger

Cadmium-tolerant (6 mM)Aspergillus niger(RCMB 002002) biomass was challenged with aqueous cadmium chloride (1 mM) followed by sodium sulfide (9 mM) at 37°C for 96 h under shaking conditions (200 rpm), resulting in the formation of highly stable polydispersed cadmium sulfide nanoparticles (CdSNPs). Scanning electron microscopy revealed the presence of spherical particles measuring approximately 5 nm. A light scattering detector (LSD) showed that 100% of the CSNPs measure from 2.7 to 7.5 nm. Structural analyses by both powder X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) confirmed the presence of cubic CdS nanoparticles (CdSNPs) capped with fungal proteins. These CdSNPs showed emission spectra with a broad fluorescence peak at 420 nm and UV absorption onset at 430 nm that shifted to 445 nm after three months of incubation. The CdSNPs showed antimicrobial activity againstE. coli,Pseudomonas vulgaris,Staphylococcus aureus, andBacillus subtilis, and no antimicrobial activity was detected againstCandida albicans. The biosynthesized CdSNPs have cytotoxic activity, with 50% inhibitory concentrations (IC50) of 190 μg mL-1against MCF7, 246 μg mL-1against PC3, and 149 μg mL-1against A549 cell lines.

Extracellular biosynthesis of biocompatible cadmium sulfide quantum dots using Trametes versicolor

Quantum dots are important fluorescent semiconductor nano-crystals with distinguished electrical and optical properties and have gained great interest in many fields. The chemical and physical synthetic methods are usually not favorable for biological application due to high energy-consumption procedure and residual toxic chemicals. The development of novel "green" routes to prepare bio-compatible cadmium sulfide quantum dots constitutes a promising substituted approach. We used the white rot fungus Trametes versicolor for the biosynthesis of cadmium sulfide quantum dots taking account of the adsorption property of this fungus. Multiple physical characterizations involving scanning electron microscope (SEM), ultraviolet-visible (UV-vis) and photoluminescence (PL) spectroscopy, fourier transform infrared spectroscopy (FTIR), thermo-gravimetric (TG), transmission electron microscopy (TEM) and X-ray diffraction (XRD) confirmed surface, optical and thermal characteristics, crystalline nature, size and shape distributions of the nanoparticles. This study provided a suitable and efficient approach to synthesize stable biocompatible cadmium sulfide quantum dots using the fungus Trametes versicolor with great potentials in the biological and biomedical researches.

Biosynthesis of Inorganic Nanoparticles: A Fresh Look at the Control of Shape, Size and Composition

Several methodologies have been devised for the design of nanomaterials. The "Holy Grail" for materials scientists is the cost-effective, eco-friendly synthesis of nanomaterials with controlled sizes, shapes and compositions, as these features confer to the as-produced nanocrystals unique properties making them appropriate candidates for valuable bio-applications. The present review summarizes published data regarding the production of nanomaterials with special features via sustainable methodologies based on the utilization of natural bioresources. The richness of the latter, the diversity of the routes adopted and the tuned experimental parameters have led to the fabrication of nanomaterials belonging to different chemical families with appropriate compositions and displaying interesting sizes and shapes. It is expected that these outstanding findings will encourage researchers and attract newcomers to continue and extend the exploration of possibilities offered by nature and the design of innovative and safer methodologies towards the synthesis of unique nanomaterials, possessing desired features and exhibiting valuable properties that can be exploited in a profusion of fields.

Mycosynthesis of nanoparticles using edible and medicinal mushrooms

This review distinguishes myco-nanotechnology using metallic nanoparticles (meta-NPs) synthesized from edible mushroom matter. Green chemistry approaches were attempted to myco-synthesize meta-NPs (viz., Ag-NP, Au-NP, Se-NP, CdS-NP, Fe-NP, Pa-NP, and ZnS-NP) via different routes using edible mushrooms and have been tested toward 79% biomedical and 21% industrial applications. Biomaterials were used as biofactors to form metallic NPs. In mushroom science, mycomaterials of mushrooms were used at different percentages to mycosynthesize in an ecofriendly/green way; mycomaterials such as crude extracts of basidocarp (53%), mycelial extract or free cell filtrate (28%), in crude form or in purified form such as polysaccharides at different percentages; 9% (especially glucan), proteins/enzymes (7%) and polysaccharides protein complex (3%) as new research lines. Generally, in this field of mushroom nanoparticles about 84% of mycosynthesized NPs using mushrooms are placed outside the fungal cell (extracellular) and 16% are intracellular in the mushroom hyphae. The knowledge of the performance and influence of meta-NPs in edible mushrooms has developed in the last 10 years. Generally, while

Extracellular Synthesis of Luminescent CdS Quantum Dots Using Plant Cell Culture

The present study describes a novel method for preparation of water-soluble CdS quantum dots, using bright yellow-2 (BY-2) cell suspension culture. Acting as a stabilizing and capping agent, the suspension cell culture mediates the formation of CdS nanoparticles. These semiconductor nanoparticles were determined by means of an UV-visible spectrophotometer, photoluminescence, high-resolution transmission electron microscopy (HRTEM), and XRD. Followed by the electron diffraction analysis of a selected area, transmission electron microscopy indicated the formation of spherical, crystalline CdS ranging in diameter from 3 to 7 nm and showed wurtzite CdS quantum dots. In the present work, the toxic effect of synthesized CdS quantum dots on Nicotiana tabacum protoplasts as a very sensitive model was under study. The results of this research revealed that biologically synthesized CdS nanoparticles in low concentrations did not induce any toxic effects.

Comparative study on toxicity of extracellularly biosynthesized and laboratory synthesized CdTe quantum dots

Nanobiosynthesis belongs to the most recent methods for synthesis of nanoparticles. This type of synthesis provides many advantages including the uniformity in particle shape and size. The biosynthesis has also a significant advantage regarding chemical properties of the obtained particles. In this study, we characterized the basic properties and composition of quantum dots (QDs), obtained by the extracellular biosynthesis by Escherichia coli. Furthermore, the toxicity of the biosynthesized QDs was compared to QDs prepared by microwave synthesis. The obtained results revealed the presence of cyan CdTe QDs after removal of substantial amounts of organic compounds, which stabilized the nanoparticle surface. QDs toxicity was evaluated using three cell lines Human Foreskin Fibroblast (HFF), Human Prostate Cancer cells (PC-3) and Breast Cancer cells (MCF-7) and the MTT assay. The test revealed differences in the toxicity between variants of QDs, varying about 10% in the HFF and 30% in the MCF-7 cell lines. The toxicity of the biosynthesized QDs to the PC-3 cell lines was about 35% lower in comparison with the QDs prepared by microwave synthesis.