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Hidden hunger is a significant social issue in numerous countries worldwide, causing the development of nutrition-related diseases among populations annually. Biofortification offers a sustainable solution as it combines methods of cross-breeding, genetic engineering, agriculture, and microbiology. The authors reviewed international studies in the field of microbial biofortification in order to assess the microbial potential to enh ance the essential element content in grain crops. The review featured relevant scientific articles published by foreign experts in Scopus, ScienceDirect, and Google Scholar in 1984–2024. The keywords included biofortification, wheat, rice, oats, growth stimulation, antagonism, and phytopathogen. The sources were processed in Zotero and VOSviewer. Nitrogen fixation and nutrient solubilization are the main mechanisms of microbial biofortification. Solubilization occurs as a synthesis of organic and inorganic acids, protons, siderophores, extracellular enzymes, and other secondary metabolites. Microorganisms can improve the expression of plant genes in terms of absorption and nutrient accumulation. They also affect root systems, facilitating the extraction of nutrients from the soil. The authors summarized laboratory and field studies on microbial biofortification of rice, wheat, and barley with iron, selenium, zinc, copper, manganese, nitrogen, phosphorus, and potassium. Biofortified growth-promoting microorganisms are a sustainable, reliable, and cost-effective approach to food security and hidden hunger issues. The review offers relevant information that can be used to develop new microbial preparations for the domestic agriculture.

Background. Ageing is associated with progressive impairment of physical functions and increased risk of age-related chronic diseases. Polyphenols such as mangiferin, quercetin and trans-cinnamic acid are also used for the treatment and prevention of chronic diseases. Toxicological research was important in biomedical research, as some high-dose extracted polyphenols could contribute to the development and progression of cancer and other diseases. This study is aimed at assessing toxicological safety of previously isolated phenolic compounds from plants of the Siberian Federal District. Materials and methods. Rodents have been chosen as the model organism. The study of mutagenic and antimutagenic properties was carried out using a micronuclear test of bone marrow cell. Cytotoxicity in vitro was assessed using the MTT test. Results. Polyphenols studied at doses of 50.0 and 100.0 mg/kg are not mutagenic. Mangiferri and quercetin at a dose of 50.0 mg/kg do not have anti-thagenic effects. In this case, trans-cinnamic acid in the same concentration has antimutagenic effect. Mangiferin in concentrates from 4.2 to 16.7 ug/ml has a cytotoxic effect. Trans-cinnamic acid is not cytotoxic (at 2.1-33.3 ug/ml). Quercetin has a cytotoxic effect in concentrations of 0.21 and 1.67 ug/ml, and at concentrations of 3.33 ug/ml increases the viability of splenocytes, presumably due to antioxidant properties. Conclusion. Safety or low toxicity is a decisive advantage of the continued use of polyphenols as advanced heroic flow agents. Further study of biologically active substances (mangiferin, quercetin and trans-cinnamic acid) has been found to be ce-woody. The work was carried out by the state task on the topic «Development of biologically active additives consisting of metabolites of plant objects in vitro to protect the population from premature aging» (project FZSR-2024-0008) using the equipment of Center of Collective Use «Instrumental methods of analysis in the field of applied biotechnology» on the basis of KemSU.

Wheat (Triticum L.) is a strategically important agricultural crop because its quality and yield provide food security for the population. Biological fertilizers improve the growth and development of agricultural crops. Unlike chemical ones, they have no toxic effect on people and the environment. This research assessed the positive effect of extremophilic microorganisms isolated from coal dump soils of the Kemerovo Region (Russia) on the growth and development of wheat. The study featured bacterial isolates of Achromobacter denitrificans, Klebsiella oxytoca, and Rhizobium radiobacter, as well as their consortia in four different ratios: 1:1:1 (Consortium A), 2:1:1 (Consortium B), 1:2:1 (Consortium C), 1:1:2 (Consortium D), respectively. The beneficial effect was assessed by determining such factors as nitrogen fixation, solubilization of phosphates, potassium, and zinc, and production of gibberellic acid, siderophores, and hydrogen cyanide. The wheat samples were checked for germination, root length, and stem length. R. radiobacter demonstrated the best nitrogen fixation properties. Consortium D, with two shares of R. radiobacter, yielded the best results for zinc solubilization. R. radiobacter proved to be the most efficient potassium solubilizer while the isolate of A. denitrificans was the best phosphate solubilizer. The largest amount of gibberellic acid belonged to K. oxytoca. Consortium C, which included two shares of this isolate, appeared to be the most effective siderophore producer. All samples but A. denitrificans were able to produce hydrogen cyanide. The best seed germination rate (84%) belonged to Consortium C, which contained a double share of K. oxytoca. Consortia C and B (two shares of A. denitrificans) had the greatest positive effect on the root length. Treatment with Consortium B resulted in the longest average stem length. Extremophilic microorganisms isolated from coal dump soils of the Kemerovo Region (Russia) had a good potential as biofertilizers that could improve wheat quality and local food security.

Wheat is a vital agricultural crop whose phytopathogens include fungi of the genera Fusarium and Alternaria. Synthetic pesticides, which are used to combat them, have a negative impact on the environment. Therefore, there is a need for developing safe and effective biopesticides. We aimed to create a consortium of extremophilic microorganisms isolated from natural sources to protect wheat from the diseases caused by Alternaria and Fusarium fungi. Ten isolates of extremophilic microorganisms were tested for their antimicrobial activity against Escherichia coli and their antagonistic activity against phytopathogens. Based on the results, we developed microbial consortia and evaluated their effectiveness in protecting wheat from phytopathogens. Five of the strains under study showed the highest activity, three of which were biocompatible, namely Leclercia sp., Sphingomonas paucimobilis, and Lactobacillus plantarum. Four consortia were created from these microorganisms, of which consortium B (with a 2:1:1 ratio of the strains, respectively) proved the most effective. In particular, it increased the area free from the phytopathogen by 4.2% compared to the average values of its individual microorganisms. Also, the consortium had a phytostimulating effect on wheat seedlings (germination of 73.2–99.6%) and protected the seeds infected with phytopathogens from morphometric changes. The resulting consortium can be used as a biopesticide since it is highly effective in protecting wheat from Alternaria and Fusarium pathogens.

Abiotic and biotic stresses have a major impact on crop growth. Stress affects the root system and decreases the amount of nutrients in fruits. Modern agricultural technologies help replace mineral fertilizers with new generation biopreparation. Unlike chemical fertilizers, biofertilizers reduce the risk of adverse environmental impacts. Of special interest are extremophilic microorganisms able to survive in extreme conditions. We aimed to study the phytostimulating ability of extremophilic bacteria isolated from disturbed lands in the coal-mining region. We isolated microorganisms from disturbed lands and studied their cultural, morphological, and biochemical properties. Then, we determined their ability to synthesize indole-3-acetic acids. The extremophilic bacteria were identified and subjected to biocompatibility testing by co-cultivation. Next, we created consortia of pure cultures and analyzed biomass growth. Finally, the biopreparation was experimentally tested on Trifolium prantense L. seeds. We isolated 10 strains of microorganisms that synthesized 4.39 to 16.32 mg/mL of indole-3-acetic acid. The largest amounts of the acid were produced by Pantoea spp., Enterococcus faecium, Leclercia spp., Rothia endophytica, and Klebsiella oxytoca. A consortium of Pantoea spp., E. faecium, and R. endophytica at a ratio of 1:1:1 produced the largest amount of indole-3-acetic acid (15.59 mg/mL) and accumulated maximum biomass. The addition of 0.2% L-tryptophan to the nutrient medium increased the amount of indole-3-acetic acid to 18.45 mg/mL. When the T. prantense L. seeds were soaked in the biopreparation (consortium’s culture fluid) at a concentration of 2.5, the sprouts were 1.4 times longer on the 10th day of growth, compared to the control. The consortium of Pantoea spp., E. faecium, and R. endophytica (1:1:1) stimulated the growth of T. prantense L. seeds. Our findings can be further used to develop biofertilizers for agriculture.

Due to the large amount of pollution at coal spoil heaps, soil reclamation is slow and requires development and use of microbial preparations, selected based on assessments of the biochemical parameters of soil and the extent of its contamination. The material for this study was mine soils sampled in three different zones (Ka, Kb, Kc) of the Korchakol coal spoil heap. The studied sanitary and chemical indicators did not exceed the approximate permissible concentrations (APC) / maximum allowable concentrations (MAC), except for oil products (in the Ka, Kb, Kc zones, the excess averaged 2.2, 1.4, 1.2 times, respectively). The study found a direct correlation between the zinc content and the enzymatic activity of polyphenol oxidase, the level of Ni and peroxidase, as well as an inverse correlation between the As and Cu concentrations with invertase and nitrite reductase, respectively. The index of bacteria of the Escherichia coli group (coliform bacteria) in different zones exceeded the standard values by 61 and 171 times. Even though the sanitary indicators studied do not exceed permissible levels, they can slow down growth and development of plants. Thus, successful reclamation of mine soils requires introduction of biological preparations based on microorganisms that biotransform heavy metals and rhizobacteria.

Heavy-metal contaminants are one of the most relevant problems of contemporary agriculture. High toxicity and the ability to accumulate in soils and crops pose a serious threat to food security. To solve this problem, it is necessary to accelerate the pace of restoration of disturbed agricultural lands. Bioremediation is an effective treatment for agricultural soil pollution. It relies on the ability of microorganisms to remove pollutants. The purpose of this study is to create a consortium based on microorganisms isolated from technogenic sites for further development in the field of soil restoration in agriculture. In the study, promising strains that can remove heavy metals from experimental media were selected: Pantoea sp., Achromobacter denitrificans, Klebsiella oxytoca, Rhizobium radiobacter, and Pseudomonas fluorescens. On their basis, consortiums were compiled, which were investigated for the ability to remove heavy metals from nutrient media, as well as to produce phytohormones. The most effective was Consortium D, which included Achromobacter denitrificans, Klebsiella oxytoca, and Rhizobium radiobacter in a ratio of 1:1:2, respectively. The ability of this consortium to produce indole-3-acetic acid and indole-3-butyric acid was 18.03 μg/L and 2.02 μg/L, respectively; the absorption capacity for heavy metals from the experimental media was Cd (56.39 mg/L), Hg (58.03 mg/L), As (61.17 mg/L), Pb (91.13 mg/L), and Ni (98.22 mg/L). Consortium D has also been found to be effective in conditions of mixed heavy-metal contamination. Due to the fact that the further use of the consortium will be focused on the soil of agricultural land cleanup, its ability to intensify the process of phytoremediation has been studied. The combined use of Trifolium pratense L. and the developed consortium ensured the removal of about 32% Pb, 15% As, 13% Hg, 31% Ni, and 25% Cd from the soil. Further research will be aimed at developing a biological product to improve the efficiency of remediation of lands withdrawn from agricultural use.