Climate changes cause various types of abiotic stress in plants, thus affecting plant growth and causing decline in yield. An urgent need exists to develop an environmentally friendly attitude based on principles of sustainable agriculture. Nanomaterials may improve plant growth and enhance crop productivity by handling the conditions considered stressful for plants in a sustainable and ecofriendly manner. Selenium (Se) has been put into the category of beneficial elements in plants. Se-enriched crops present a successful choice of dietary resource for Se-supplemented food and feed owing to their high bioavailability and accessibility. Researchers from distinct areas, including both nanoscience and plant science, should encourage emerging innovations that are linked with abiotic stress in crop production. The implementation of Se nanoparticles (SeNPs) is considered one of the predominating mechanisms by plants to ameliorate stressful conditions. Increasing evidence of earlier research revealed that SeNPs could enhance plant growth and development, nutrient bioavailability, soil fertility, and stress response while maintaining environmental safety. Meanwhile, some earlier studies reported that SeNPs might have a multilateral influence on plants dependent on diverse Se nanomaterial traits, doses, and plant species. More efforts are required to enhance the knowledge of how SeNPs impact crops exposed to different abiotic detrimental factors. In light of contemporary research challenges linked to SeNPs and the prolonged application of Se nanomaterials to plants, the aim of this review is elucidating the principal fruitful areas of SeNP exploration, comparisons with bulk Se, insights into mechanisms of abiotic stress alleviation in plants, existing research uncertainties, and practical challenges for SeNP applications under varying environments.

Higher-fungi xylotrophic basidiomycetes are known to be the reservoirs of bioactive metabolites. Currently, a great deal of attention has been paid to the exploitation of mycelial fungi products as an innovative alternative in crop protection. No data exist on the mechanisms behind the interaction between xylotrophic mushrooms’ glycopolymeric substances and plants. In this study, the effects of basidiomycete metabolites on the morphophysiological and biochemical variables of wheat plants have been explored. Wheat (Triticum aestivum L. cv. Saratovskaya 29) seedlings were treated with extracellular polysaccharides (EPSs) isolated from the submerged cultures of twenty basidiomycete strains assigned to 13 species and 8 genera. The EPS solutions at final concentrations of 15, 40, and 80 mg/L were applied to wheat seedlings followed by their growth for 10 days. In the plant samples, the biomass, length of coleoptile, shoot and root, root number, rate of lipid peroxidation by malondialdehyde concentration, content of hydrogen peroxide, and total phenols were measured. The peroxidase and superoxide dismutase activity were defined. Most of the EPS preparations improved biomass yields, as well as the morphological parameters examined. EPS application enhanced the activities of antioxidant enzymes and decreased oxidative damage to lipids. Judging by its overall effect on the growth indices and redox system of wheat plants, an EPS concentration of 40 mg/L has been shown to be the most beneficial compared to other concentrations. This study proves that novel bioformulations based on mushroom EPSs can be developed and are effective for wheat growth and antioxidative response. Phytostimulating properties found for EPSs give grounds to consider extracellular metabolites produced in the xylotrophic basidiomycete cultures as an active component capable of inducing plant responses to stress.

New ammonium hydrazones have been synthesized by the reaction of Girard’s reagents T and P with isatin derivatives that contain various alkyl or geranyl substituents in position 1. A pronounced anti-anthropo- and antiphyto-pathogenic effect of resulting compounds has been revealed. The n-octyl and octadiene derivatives have the highest selectivity for resistant strains of Staphylococcus aureus when there is no negative effect on the hemostasis system. The aggregation and adsorption properties of the compounds have been studied using tensiometry, conductometry, and UV spectroscopy. The found values of the critical micelle concentration of amphiphilic ammonium hydrazones are an order of magnitude lower than those of quaternary ammonium salts.

A series of new fluorinated 1-benzylisatins was synthesized in high yields via a simple one-pot procedure in order to explore the possible effect of ortho-fluoro (3a), chloro (3b), or bis-fluoro (3d) substitution on the biological activity of this pharmacophore. Furthermore, the new isatins could be converted into water-soluble isatin-3-hydrazones using their acid-catalyzed reaction with Girard’s reagent P and its dimethyl analog. The cytotoxic action of these substances is associated with the induction of apoptosis caused by mitochondrial membrane dissipation and stimulated reactive oxygen species production in tumor cells. In addition, compounds 3a and 3b exhibit platelet antiaggregation activity at the level of acetylsalicylic acid, and the whole series of fluorine-containing isatins does not adversely affect the hemostasis system as a whole. Among the new water-soluble pyridinium isatin-3-acylhydrazones, compounds 7c and 5c,e exhibit the highest antagonistic effect against phytopathogens of bacterial and fungal origin and can be considered useful leads for combating plant diseases.

Coumarin derivatives (coumarins, chromen-2-ones) attract interest because, on the one hand, of their wide practical application, and from other hand, the unique reactivity of the chromen-2-one system in molecular structure. Coumarins are benzopyrone compounds belonging to the flavonoid group of secondary metabolites. Presently there are more than 1300 coumarins have been identified in plants, bacteria, and fungi. Coumarins have their specific fingerprints as antiviral, antimicrobial, antioxidant, antiinflammatory, antiadipogenic, cytotoxic, apoptosis, antiprolilferative, antitubercular, and cytotoxicity agents. Due to their wide range of pharmacological values, coumarins and their derivatives have gained more importance in synthesis and production. Organisms such as cultivated microbes, including mushrooms and lower fungi, have provided much of the chemical diversity inspiring syntheses and filling the pharmaceutical pipeline. Natural coumarins possess anticancer, antiHIV, antidiabetic, and other effects. Coumarins have been found to exhibit antioxidative properties and radical scavenging activities in various studies. Free radicals, or reactive oxygen species (ROS), are produced in vivo from various biochemical reactions and implicated in the causation of diseases such as diabetes, inflammation, cancer, neurodegenerative disorders, atherosclerosis, liver cirrhosis, nephrotoxicity, etc. According to recent reports, a highly positive relationship between total flavonoids and antioxidant activity appears to be the trend in many phyto species. Coumarins, as one of the flavonoids subclasses, thus play an important role to protect the human body against damage by ROS. For the production of these versatile agents, coumarin derivatives, the promised plant symbiotic fungi can be used. Endophytes are any ubiquitous organisms, such as bacteria or fungi, occurring within plant tissues, distinct from the epiphytes that live on plant surfaces. The properties of endophytes are beneficial industrially in the production of important secondary metabolites. Endophytic fungi are microorganisms hidden within healthy host plants, but they do not cause any harm and are able to produce the bioactive compounds that the host plant is producing. These active molecules are exploited from endophytes for a variety of medicinal, agricultural, and industrial purposes. Endophytes frequently demonstrate the biological activities of antimicrobial, antioxidant, anticancer, and antiHIV agents. Many endophytic fungal extracts contain coumarin constituents and show inhibitory activity against such pathogenic bacteria as Proteus vulgaris, Salmonella typhimurium, Staphylococcus aureus, Staphylococcus faecalis, Xanthomonas campestris, and Klebsiella pneumonia. Being considered to be the choice as apoptotic agents, these endophytic fungal coumarins possess apoptotic activity against HeLa cervical cancer cell lines. Coumarins are widespread in the plant kingdom, with only unity research being related to the elucidation and exploration the action of that group of compounds with respect to mushrooms, which are higher fungi. Medicinal mushrooms have become a compelling topic because the bioactive compounds they contain promise a plethora of therapeutic properties. Numerous bioactive compounds of important medicinal mushrooms have been developed into food supplements and alternative medicines. The fermented mycelia have been reported to produce several classes of bioactive molecules, including polysaccharides, proteins, lectins, phenols, terpenoids, etc. Scientists have also screened the antimicrobial properties of mushrooms to find a solution for antibiotic drug resistance in human pathogenic microorganisms. Mushrooms are among the essential sources of antioxidants in the diet. Natural antioxidants may have free-radical scavengers, reducing agents, complexes of prooxidant metals, quenchers of singlet oxygen, etc. Recently, interest has increased considerably in finding naturally occurring antioxidants for use in foods or medicinal products to replace synthetic antioxidants, which are being restricted due to their adverse reactions such as carcinogenicity. Thus, the examples of a wide range of biological effects of natural coumarins are known as the basis of low-toxic and highly effective drugs. We showed previously that some coumarins exhibited antimicrobial activity when they were included in the composition of biocomposites of fungal origin. One of the potential applications of such biocomposites is the regulation of the number of bacterial phytopathogens. The newly synthesized by our colleagues coumarin derivatives were studied as a component of the basidiomycetes' nutrient media. Bactericidal activity of the mycelial biomass products against phytopathogenic bacteria from Micrococcus, Pectobacterium, Pseudomonas, and Xanthomonas genera was found. The effect of nitro group-containing compounds as a component of growth medium for mycelium implemented in the potentially bactericidal specimen manufacture appeared to be much more pronounced. Species-specific peculiarities of the above bioactivity manifestation for fungal biopolymers took place. Research into the ways of obtaining and the possibility of practical use of the biometals(II) complexes based on the coumarin fragment-containing systems seems actual due to the high biological activity of coumarins, which are quite promising for solving problems in crop production and plant protection. In a recent work, the complexes of Cu(II), Mn(II), and Zn(II) with 4-hydroxy-3-(3-oxo-1,3-diphenylpropyl)-chromen-2-one and 4-hydroxy-3-(3-oxo-1-(3-nitrophenyl)-3-phenylpropyl)-chrome-2-one were synthesized. The antibacterial activity of the products of these complexes biotransformation by basidiomycetes against a number of phytopathogenic bacteria was elucidated. In respect to the extracellular fungal metabolites antibacterial activity, the leading place was occupied by the Cu(II) complex with 4-hydroxy-3-(3-oxo-1,3-diphenylpropyl)-chromen-2-one. Extracellular metabolites of Laetiporus sulphureus, Lentinula edodes facilitated the formation of biopreparations with more pronounced bactericidal activity. Promising are further studies of conditions and products of the natural and synthetic coumarins' biotransformation by the fungal cultures, aimed at solving the urgent problem of searching materials for agricultural and biomedical engineering.

Superoxide is the primary active oxygen form produced in living organisms. Because of superoxide anion radical formation during epinephrine oxidation in alkaline medium, this system is offered in some works for antioxidant activity analysis, however, without enough physicochemical justification. Therefore, the task of developing reliable methods for analyzing the superoxide inhibition activity of various objects is very urgent. In this work, a kinetic model of epinephrine autoxidation in an alkaline medium in the presence of antioxidants of plant origin is proposed. The participation of chain reactions with long oxidation chains in this process is revealed. The limiting stage of the process is a one-electron reduction of oxygen by the anionic forms of the phenolic hydroxyls of epinephrine. The appearance of the absorption maximum at a wavelength of 347 nm during epinephrine autoxidation is associated with adrenolutin formation, which is confirmed by HPLC/UV/MS. No adduct formation between phenolic antioxidants and epinephrine oxidation products was found. The complex U-shaped character of epinephrine autoxidation rate dependence on the content of antioxidants in the reaction system was shown. The study of the kinetics of epinephrine autoxidation in the presence of an individual phenolic plant superoxide inhibitor, chlorogenic acid, was carried out for the first time. The inhibitory effect of yarrow, chamomile, and bur beggar-ticks plant extracts in the adrenaline system was examined.

The reaction of bisisatins containing a 1,ω-alkylene, -arylene, or -alkyluracil spacer with ammonium acetohydrazides gave a series of symmetric and asymmetric dicationic isatin-3-acylhydrazones. It was shown that the antimicrobial activity of the new compounds depends on the structure of the spacer and the nature of the substituent in the aromatic fragment. 5-Substituted isatin derivatives, where the heterocyclic fragments are linked by an 9- and 10-carbon alkylene chains, exhibit bactericidal effect against resistant strains of S. aureus at the level of Norfloxacin and the fungal pathogen P. cactorum , which causes plant late blight.

The interaction of bis-isatins containing a 1,-ω-alkylene, arylene, or alkyluracil spacer with ammonium acetohydrazides yielded a series of dicationic isatin-3-acylhydrazones with symmetric and asymmetric structures. It was shown that the antimicrobial activity of the new compounds depends on the structure of the spacer and the nature of the substituent in the aromatic fragment. Derivatives based on 5-substituted isatins, in which heterocyclic fragments are linked by an alkylene chain of 9 and 10 carbon atoms, exhibit a bactericidal effect against resistant strains of Staphylococcus aureus at the level of norfloxacin and the pathogen fungus P. cactorum , which causes plant late blight.

The influence of nanoparticles of hydrated C60 fullerene and its N-monoamino acid derivatives on the oxidative metabolism and growth of the mycelial biomass of basidiomycetes during their submerged cultivation was studied. It was found that the supplementation of culture media with nanoparticles of the studied compounds at their final concentration range of 10−7 to 10−11 M significantly increased the resulting biomass, while the severity of the effect in this concentration range changed slightly. That prompted the use of nanomolar concentrations of compounds as reasonable. The most pronounced stimulating effect (an increase in biomass of about 240% with respect to control) was observed when culturing Laetiporus sulphureus, the intrinsically high level of oxidative metabolism of which was significantly lowered by the presence of the studied additives. It was shown that the growth-enhancing action of nanoparticles of fullerene C60 and its derivatives could not be attributed to photochemical reactions, particularly fullerene photoexcitation. Fullerene and its derivatives manifest a growth regulatory effect on bio-objects from different kingdoms of the living world (plants and fungi), which is indicative of these compounds’ mechanism of action based on a direct impact on fundamental, universal for all living beings, biophysical processes, primarily chain free-radical oxidation.

Coumarins are a structurally varied set of 2H-chromen-2-one compounds categorized also as members of the benzopyrone group of secondary metabolites. Coumarin derivatives attract interest owing to their wide practical application and the unique reactivity of fused benzene and pyrone ring systems in molecular structure. Coumarins have their own specific fingerprints as antiviral, antimicrobial, antioxidant, anti-inflammatory, antiadipogenic, cytotoxic, apoptosis, antitumor, antitubercular, and cytotoxicity agents. Natural products have played an essential role in filling the pharmaceutical pipeline for thousands of years. Biological effects of natural coumarins have laid the basis of low-toxic and highly effective drugs. Presently, more than 1300 coumarins have been identified in plants, bacteria, and fungi. Fungi as cultivated microbes have provided many of the nature-inspired syntheses of chemically diverse drugs. Endophytic fungi bioactivities attract interest, with applications in fields as diverse as cancer and neuronal injury or degeneration, microbial and parasitic infections, and others. Fungal mycelia produce several classes of bioactive molecules, including a wide group of coumarins. Of promise are further studies of conditions and products of the natural and synthetic coumarins' biotransformation by the fungal cultures, aimed at solving the urgent problem of searching for materials for biomedical engineering. The present review evaluates the fungal coumarins, their structure-related peculiarities, and their future therapeutic potential. Special emphasis has been placed on the coumarins successfully bioprospected from fungi, whereas an industry demand for the same coumarins earlier found in plants has faced hurdles. Considerable attention has also been paid to some aspects of the molecular mechanisms underlying the coumarins' biological activity. The compounds are selected and grouped according to their cytotoxic, anticancer, antibacterial, antifungal, and miscellaneous effects.

A series of biorelevant triethylammonium isatin hydrazones containing various substituents in the aromatic fragment have been synthesized. Their structure and composition were confirmed by NMR- and IR-spectroscopies, mass-spectrometry and elemental analysis. It was found that some representatives show activity against Staphylococcus aureus and Bacillus cereus higher or at the level of norfloxacin, including methicillin-resistant Staphylococcus aureus strains. The study also showed low hemo- and cytotoxicity (Chang Liver) and high antiaggregatory and anticoagulant activity of these compounds. The high potential of new ammonium isatin-3-acylhydrazones in the search for antimicrobial activity against phytopathogens of bacterial and fungal nature has been shown for the first time.

Multicomponent materials, where nanosized selenium (Se) is dispersed in polymer matrices, present as polymer nanocomposites (NCs), namely, selenium polymer nanocomposites (SeNCs). Selenium as an inorganic nanofiller in NCs has been extensively studied for its biological activity. More ecologically safe and beneficial approaches to obtain Se-based products are the current challenge. Biopolymers have attained great attention with perspective multifunctional and high-performance NCs exhibiting low environmental impact with unique properties, being abundantly available, renewable, and eco-friendly. Composites based on polysaccharides, including beta-glucans from edible and medicinal mushrooms, are bioactive, biocompatible, biodegradable, and have exhibited innovative potential. We synthesized SeNCs on the basis of the extracellular polysaccharides of several medicinal mushrooms. The influence of bio-composites from mushrooms on potato plant growth and tuber germination were studied in two potato cultivars: Lukyanovsky and Lugovskoi. Bio-composites based on Grifola umbellata demonstrated the strongest positive effect on the number of leaves and plant height in both cultivars, without negative effect on biomass of the vegetative part. Treatment of the potato tubers with SeNC from Gr. umbellata also significantly increased germ length. Potato plants exposed to Se-bio-composite from Ganoderma lucidum SIE1303 experienced an increase in the potato vegetative biomass by up to 55% versus the control. We found earlier that this bio-composite was the most efficient against biofilm formation by the potato ring rot causative agent Clavibacter sepedonicus (Cms). Bio-composites based on Pleurotus ostreatus promoted increase in the potato root biomass in the Lugovskoi cultivar by up to 79% versus the control. The phytostimulating ability of mushroom-based Se-containing bio-composites, together with their anti-phytopathogenic activity, testifies in favor of the bifunctional mode of action of these Se-biopreparations. The application of stimulatory green SeNCs for growth enhancement could be used to increase crop yield. Thus, by combining myco-nanotechnology with the intrinsic biological activity of selenium, an unexpectedly efficient tool for possible applications of SeNCs could be identified.

Abstract Investigations of biologically active substances sourced from xylotrophic macromycetes have shown their fundamental and practical significance. These studies have promoted the development of biotechnologies by obtaining the valuable products from the mycelial biomass and cultivation liquid and using these fungal species in “white chemistry”. Research into environmentally safe biological methods of stimulating the growth of medicinal and edible mushrooms can assist the development of scientific foundations of culture technologies. From the viewpoint of their bio-technological potential, selected factors of biological origin that promote the growth of wide-scale cultivated basidiomycetes are of interest. Improving mushroom resistance against negative environmental impacts seems to be feasible when the mushroom grows in combination with growth-promoting bacteria. The soil bacteria from the Azospirillum genus have attracted attention, as microorganisms are capable of actively influencing the growth and development of agricultural crops. Thus, revealing and exploring the growth-promoting properties of different species of Azospirillum with respect to edible and/or medicinal mushrooms, as well as the properties promoting the suppression of contaminants in double culture, are believed to be feasible and to reveal undoubted novelty. Cultivation jointly with the beneficial bacteria is a more effective biotechnological method for obtaining this valuable functional food faster, with a greater and much better and maintained mushroom yield. Future work involves addressing the problems of mushroom growth promoting bacterial interactions with mushrooms and implementing these synthetic microbial associations into agriculture.

We report the synthesis of water-soluble spherical SeS2 nanoparticles using the stabilizing ability of arabinogalactan from Larix Sibirica as well as the ion-exchange interaction of ammonium sulfide and selenic acid. The average size of the SeS2 nanoparticles in the obtained composites was determined by the synthesis conditions, in particular by the ratio of the Se and S precursor ions to arabinogalactan and varied from 26 to 39 nm for composites containing 2.05–12.0

The condensation reaction of 4,6-di-tert-butyl-2,3-dihydroxybenzaldehyde with some ammonium acetohydrazides yielded water-soluble acylhydrazones with different structures of the cationic center. It was shown that in relation to Staphylococcus aureus, Bacillus cereus and Enterococcus faecalis, trimethylammonium chloride derivative exhibits activity at or above the level of comparison drugs, norfloxacin and chloramphenicol, respectively. The resulting compounds do not have a toxic effect on erythrocytes and normal human liver cells. The high activity of diethylmethylammonium acylhydrazone against the formation of biofilms formed by clinical staphylococci strains was shown for the first time. The high efficiency of new compounds in inhibiting the growth of phytopathogens of bacterial and fungal origin was established.

We studied the effects of new chemically synthesized selenium (Se) nanocomposites (NCs) based on natural polysaccharide matrices arabinogalactan (AG), starch (ST), and kappa-carrageenan (CAR) on the viability of phytopathogen Phytophthora cactorum, rhizospheric bacteria, and potato productivity in the field experiment. Using transmission electron microscopy (TEM), it was shown that the nanocomposites contained nanoparticles varying from 20 to 180 nm in size depending on the type of NC. All three investigated NCs had a fungicidal effect even at the lowest tested concentrations of 50 µg/mL for Se/AG NC (3 µg/mL Se), 35 µg/mL for Se/ST NC (0.5 µg/mL Se), and 39 µg/mL for Se/CAR NC (1.4 µg/mL Se), including concentration of 0.000625% Se (6.25 µg/mL) in the final suspension, which was used to study Se NC effects on bacterial growth of the three common rhizospheric bacteria Acinetobacter guillouiae, Rhodococcus erythropolis and Pseudomonas oryzihabitans isolated from the rhizosphere of plants growing in the Irkutsk Region, Russia. The AG-based Se NC (Se/AG NC) and CAR-based Se NC (Se/CAR NC) exhibited the greatest inhibition of fungal growth up to 60% (at 300 µg/mL) and 49% (at 234 µg/mL), respectively. The safe use of Se NCs against phytopathogens requires them to be environmentally friendly without negative effects on rhizospheric microorganisms. The same concentration of 0.000625% Se (6.25 µg/mL) in the final suspension of all three Se NCs (which corresponds to 105.57 µg/mL for Se/AG NC, 428.08 µg/mL for Se/ST NC and 170.30 µg/mL for Se/CAR NC) was used to study their effect on bacterial growth (bactericidal, bacteriostatic, and biofilm formation effects) of the three rhizospheric bacteria. Based on our earlier studies this concentration had an antibacterial effect against the phytopathogenic bacterium Clavibacter sepedonicus that causes diseases of potato ring rot, but did not negatively affect the viability of potato plants at this concentration. In this study, using this concentration no bacteriostatic and bactericidal activity of all three Se NCs were found against Rhodococcus erythropolis based on the optical density of a bacterial suspension, agar diffusion, and intensity of biofilm formation, but Se/CAR and Se/AG NCs inhibited the growth of Pseudomonas oryzihabitans. The cell growth was decrease by 15–30% during the entire observation period, but the stimulation of biofilm formation by this bacterium was observed for Se/CAR NC. Se/AG NC also had bacteriostatic and antibiofilm effects on the rhizospheric bacterium Acinetobacter guillouiae. There was a 2.5-fold decrease in bacterial growth and a 30% decrease in biofilm formation, but Se/CAR NC stimulated the growth of A. guillouiae. According to the results of the preliminary field test, an increase in potato productivity by an average of 30% was revealed after the pre-planting treatment of tubers by spraying them with Se/AG and Se/CAR NCs with the same concentration of Se of 0.000625% (6.25 µg/mL) in a final suspension. The obtained and previously published results on the positive effect of natural matrix-based Se NCs on plants open up prospects for further investigation of their effects on rhizosphere bacteria and resistance of cultivated plants to stress factors.

Nanoparticle-reinforced polymer-based materials effectively combine the functional properties of polymers and unique characteristic features of NPs. Biopolymers have attained great attention, with perspective multifunctional and high-performance nanocomposites exhibiting a low environmental impact with unique properties, being abundantly available, renewable, and eco-friendly. Nanocomposites of biopolymers are termed green biocomposites. Different biocomposites are reported with numerous inorganic nanofillers, which include selenium. Selenium is a micronutrient that can potentially be used in the prevention and treatment of diseases and has been extensively studied for its biological activity. SeNPs have attracted increasing attention due to their high bioavailability, low toxicity, and novel therapeutic properties. One of the best routes to take advantage of SeNPs' properties is by mixing these NPs with polymers to obtain nanocomposites with functionalities associated with the NPs together with the main characteristics of the polymer matrix. These nanocomposite materials have markedly improved properties achieved at low SeNP concentrations. Composites based on polysaccharides, including fungal beta-glucans, are bioactive, biocompatible, biodegradable, and have exhibited an innovative potential. Mushrooms meet certain obvious requirements for the green entity applied to the SeNP manufacturing. Fungal-matrixed selenium nanoparticles are a new promising biocomposite material. This review aims to give a summary of what is known by now about the mycosynthesized selenium polymeric nanocomposites with the impact on fungal-assisted manufactured ones, the mechanisms of the involved processes at the chemical reaction level, and problems and challenges posed in this area.

Potentialities of the mushroom-originating preparations for potato recovery are shown. The metal(II) containing composites based on the metabolites of basidiomycetes exhibits the effect of enhancing the potato resistivity to phytopathogen.