Use Of Microorganisms Research Articles

Effect of organic farming on root microbiota, seed production and pathogen resistance in winter wheat fields

Societal Impact StatementAgricultural intensification is a major driver of biodiversity decline in agrosystems. For instance, it has been shown that conventional farming leads to a decline in soil microbial diversity and triggers a strong selection process, altering the functioning of the whole ecosystem. The present study shows that organic farming increases diversity and affects composition of crop plant microbiota, mostly as a response to field management and soil characteristics. Furthermore, crop plant microbiota influences crop production and resistance to pathogens. Therefore, agricultural practices affect plant performance through microorganism‐mediated changes, which may be important pillars of future sustainable crop production.Summary Agricultural intensification threatens biodiversity, but the effects of intensification on microorganisms are still overlooked despite their role in ecosystem functioning. Microorganisms associated with plants provide many services that affect plant growth and health. Organic farming is expected to strongly affect species composition, richness, and their interactions. We analyzed the effect of the farming system on endophytic microbial assemblages associated with winter wheat plants and plant performance in the field. We collected environmental data through farmer interviews, soil analyses, and plant inventories and analyzed root microbiota at vegetative and flowering stages. Organic farming increased fungal and bacterial diversity associated to wheat plants and affected species composition in most phyla. This effect was mostly due to soil characteristics and field management and a little to plant diversity in the field. Microbial responses were more pronounced at the late developmental stage, likely as a result of accumulative effect of management actions during plant development. Seed production and resistance to pathogens were related to specific phyla that are important for seed production and/or wheat resistance to septoriose. This work advances our understanding of how agricultural practices affect plant performance through microorganism‐mediated changes and supports the use of microorganisms as pillars of sustainable crop production.

Isolation and assessment of highly sucrose-tolerant yeast strains for honey processing factory's effluent treatment.

Wastewater from many food and beverage manufacturers is enriched in organic content, and it must therefore be treated before being discharged to comply with the strict environmental regulations to protect the final water quality. Concretely, the honey processing wastewater, that remains in holding tanks until is disposal, is a rich source of sugars and this high level of organic material will degrade the water quality if not treated properly provoking an imbalance in the ecosystem. There are different strategies for an adequate treatment of this wastewater effluent to obtain a sustainable usage. One of the techniques that is more cost-effective and environmental friendlier than chemical procedures used for water remediation, is the use of microorganisms (including algae, fungi, yeasts, or bacteria). Given that they are fast-growing, robust, and metabolically diverse, yeast strains are often used for wastewater treatment. In this work, we have studied the potential for bioremediation of non Saccharomyces yeast isolated from a honey processing wastewater generated by an Argentine exporting company. The inoculation of these yeast strains to the existing flora in the honey wastewater yielded a better improvement in the treatment yield. These results suggest that these strains display a promising role could for optimizing bioremediation strategies in industrial wastewater treatment processes.

Synthesis of Nanoparticle ZnO via Chemical Reduction Using Singkil (<i>Premna serratifolia linn</i>) Leaf Extract as Photocatalytic

Nanoparticles are one of the widely studied research topics. ZnO nanoparticles have numerous benefits, such as photocatalysts and antibacterial applications. Methylene blue, which a highly dangerous and pollutes the environment and human health, is mostly used as a coloring dye in the textile industry. The use of biodegradation to treat textile waste is time-consuming and less effective. Applying photocatalysts using semiconductor materials is a more efficient method than conventional approaches for decomposing organic waste. One environmentally friendly method is green synthesis, which involves the use of microorganisms, enzymes, and plant extracts in the fabrication process. In this study, the green synthesis using chemical reduction of Premna serratifolia linn leaf extract was used to produce ZnO nanoparticles. The objective of this study is to investigate the effect of temperature on the fabrication of ZnO nanoparticles and their photocatalytic performance. Zinc nitrate tetrahydrate was used as a precursor, and the furnace temperature was varied at 400, 500, and 600 °C. The obtained ZnO was then tested using scanning electron microscopy (SEM), X-ray diffractometry (XRD), and Fourier transforms infrared spectrophotometry (FTIR). Moreover, the photocatalytic test was evaluated by examining the degradation efficiency of methylene blue using UV light. The XRD analysis indicated that the ZnO nanoparticles had crystallite sizes ranging between 44-60 nm. The SEM morphological test showed that the ZnO particles had a nano-sized spherical shape. The FTIR test results demonstrated the presence of ZnO peaks around 520 cm‑1. The performance of photocatalytic activity under UV light irradiation was significantly affected by tuning the temperatures. It was observed that the photocatalytic activity increased with increasing temperature, and methylene blue degradation efficiency reached 50% at a temperature of 600 °C. The ability of ZnO as a photocatalyst material was also evaluated by recycling the used material two times, where there was no significant change in photocatalytic performance.

Separation and purification of antimicrobial substances from Paenibacillus polymyxa KH-19 and analysis of its physicochemical characterization.

Soft rot is one of the top ten most dangerous plant pathogens in agricultural production, storage, and transport, and the use of microorganisms and their metabolites to control soft rot is a current research hotspot. In this study, we identified the antimicrobial substance in the metabolite of Paenibacillus polymyxa KH-19, and determined that the antimicrobial substance of this strain was an active protein. The protein was completely precipitated at 40-60% ammonium sulphate saturation and showed good inhibitory effects against seven pathogenic bacteria including Pectobacterium carotovorum BC2 and seven pathogenic fungi including Pyricularia oryzae. The MIC of the protein was 51.563µg/mL, temperature acid-base UV and light stability insensitive to protease, with high-temperature resistance. The antimicrobial protein was isolated and purified by DEAE-anion exchange column and Sephadex G-75 gel filtration chromatography, and the LC-MS/MS assay identified the protein as lysophosphatidyl esterase with a molecular weight of 25.255kDa. The purified antimicrobial protein increased the inhibitory effect against P. carotovorum BC2, with the diameter of the circle of inhibition being 26.50 ± 0.915mm. Bioinformatics analysis showed that the protein has the molecular formula of C1117H1732N316O338S5, encodes 224 amino acids, has an aliphatic index of 88.39, and belongs to the category of hydrophilic unstable proteins. The present study is the first report of an active protein with extreme thermoplastic and resistance to P. carotovorum BC2, which provides a reference for the preparation and application of the antimicrobial substances of P. polymyxa KH-19, as well as a theoretical basis for the study of the function of lysophosphodiesterase protein and its use as a microbial preparation.

Testing microbial pest control products in bees, a comparative study on different bee species and their interaction with two representative microorganisms

BackgroundThe evaluation of the impact of pesticides on non-target species, like bees, is a crucial factor in registration procedures. Therefore, standardized test procedures have been developed on OECD level assessing the effects of chemicals on honey bees or bumble bees. Unfortunately, these protocols cannot directly be adapted for testing products that contain microorganisms. Interest in the use of microorganisms has increased in recent years due to their specificity to target species while not harming non-target organisms. This study aimed to evaluate optimal conditions to assess the effects of microbial plant protection products on bee species according to currently available test protocols. Some of the most commonly used microorganisms for plant protection, Bacillus thuringiensis subspecies aizawai (B. t. a. ABTS 1857) and Beauveria bassiana (B. b. ATCC 74040) were tested on Apis mellifera, Bombus terrestris, and Osmia bicornis at different temperatures (18, 26, 33 °C) under laboratory conditions.ResultsExposure to the product containing B. t. a. ABTS 1857 resulted in higher mortality compared to B. b. ATCC 74040 in all tested bee species. A temperature-dependent effect towards higher mortality at higher temperatures of 26 °C or 33 °C was observed in O. bicornis exposed to both microorganisms. A. mellifera showed variable responses, but for B. terrestris there was mostly no effect of temperature when exposed to microorganisms in high concentrations. However, temperature affected longevity of bee species in the non-exposed control group. A. mellifera mortality increased with decreasing temperatures, while B. terrestris and O. bicornis mortality increased with increasing temperatures. A test duration of 15 or 20 days was found to be suitable for testing these microorganisms.ConclusionIn conclusion, 26 °C should be considered the worst-case scenario for testing B. bassiana on all tested bee species. For testing B. thuringiensis, a temperature of 33 °C is recommended for A. mellifera, whereas B. terrestris and O. bicornis should be tested at 26 °C.

Screening nitrogen-fixing cyanobacteria that can alleviate cadmium toxicity to rice and reduce cadmium accumulation in brown rice

Among food crops, rice is the most serious food crop contaminated with cadmium (Cd). It is critical to reduce Cd bioavailability in the soil and prevent its accumulation in brown rice. The use of microorganisms to lessen Cd toxicity in rice has been the subject of numerous studies carried out in recent years. The nitrogen-fixing cyanobacterium (NFC) is a potent biofertilizer and heavy metal biosorbent. However, there is a dearth of research on the impact of NFC supplementation on rice's susceptibility to Cd poisoning. This study screened for Cd-tolerant NFCs and assessed how well they might promote growth and lower the amount of Cd in rice. Four NFCs with tolerance to 1 mg L−1 Cd were selected from ten NFCs. The results of seedling experiment showed that SCAU-10 treatment increased plant height and biomass while reducing Cd levels in seedlings by 62.0 %. The pot experiment also demonstrated that SCAU-10 was effective in lowering Cd content in brown rice by 85.3 %. Reducing the bioavailability of soil Cd, shielding rice roots, preventing Cd transfer from below to above ground, generating phytohormones, and enhancing the photochemical electron quantum yield of rice leaves are a few possible action mechanisms of the NFC. It indicates that Trichormus sp. SCAU-10 has a great deal of promise for use as a biofertilizer in the safe management of Cd-contaminated rice fields. This is the first report on using Trichormus sp. biofertilizer for relieving the toxicity of Cd to rice and reducing Cd accumulation in brown rice.

Carbon dioxide capture, sequestration, and utilization models for carbon management and transformation.

The elevated level of carbon dioxide in the atmosphere has become a pressing concern for environmental health due to its contribution to climate change and global warming. Simultaneously, the energy crisis is a significant issue for both developed and developing nations. In response to these challenges, carbon capture, sequestration, and utilization (CCSU) have emerged as promising solutions within the carbon-neutral bioenergy sector. Numerous technologies are available for CCSU including physical, chemical, and biological routes. The aim of this study is to explore the potential of CCSU technologies, specifically focusing on the use of microorganisms based on their well-established metabolic part. By investigating these biological pathways, we aim to develop sustainable strategies for climate management and biofuel production. One of the key novelties of this study lies in the utilization of microorganisms for CO2 fixation and conversion, offering a renewable and efficient method for addressing carbon emissions. Algae, with its high growth rate and lipid contents, exhibits CO2 fixation capabilities during photosynthesis. Similarly, methanogens have shown efficiency in converting CO2 to methane by methanogenesis, offering a viable pathway for carbon sequestration and energy production. In conclusion, our study highlights the importance of exploring biological pathways, which significantly reduce carbon emissions and move towards a more environmentally friendly future. The output of this review highlights the significant potential of CCSU models for future sustainability. Furthermore, this review has been intensified in the current agenda for reduction of CO2 at considerable extends with biofuel upgrading by the microbial-shift reaction.

The causal association between gut microbiota and postpartum depression: a two-sample Mendelian randomization study.

An escalating body of clinical trials and observational studies hints at a plausible link between gut flora and postpartum depression (PPD). The definitive causal dynamics between these two entities remain shrouded in ambiguity. Therefore, in this study, we employed the two-sample Mendelian randomization approach to ascertain the causal link between gut microbiota and PPD. Summary-level GWAS data related to the human gut microbiota were obtained from the international consortium MiBioGen and the Dutch Microbiome Project (species). For PPD, GWAS data were derived from the FinnGen biobank, consisting 57,604 cases and 596,601 controls. The inverse variance weighted method (IVW) as the cornerstone of our analytical approach. Subsequent to this, a comprehensive suite of tests for pleiotropy and heterogeneity were conducted to ensure the reliability and robustness of our findings. We identified 12 bacterial taxa associated with the risk of PPD. Veillonellaceae, Ruminococcaceae UCG 011, Bifidobacterium adolescentis, Paraprevotella clara, Clostridium leptum, Eubacterium siraeum, Coprococcus catus exhibited an inversely associated with the risk of PPD. Alphaproteobacteria, Roseburia, FamilyXIIIAD3011group, Alistipes onderdonkii, Bilophila wadsworthia showed a positive correlation with the risk of PPD. The GWAS data derived from the MiBioGen consortium, DMP, and FinnGen consortium, may introduce selection bias. Moreover, the data primarily originates from European populations, hence extrapolating these results to diverse populations should be approached with caution. The etiological factors behind PPD remain enigmatic, alluding to the existence of potential undisclosed confounders. Based on this MR analysis, we found a causal relationship between certain gut microbial communities and PPD. Future clinical studies can further explore the treatment of PPD through the combined use of microorganisms. This not only offers insights into the pathogenesis of PPD but also lays the foundation for utilizing gut microbiota as biotherapeutics in treating neurological disorders.

Succession changes of microbial community for inferring the time since deposition of saliva.

Saliva is a common biological examination material at crime scenes and has high application value in forensic case investigations. It can reflect the suspect's time of crime at the scene and provide evidence of the suspect's criminal facts. Even though many researchers have proposed their experimental protocols for estimating the time since deposition (TsD) of saliva, there is still a relative lack of research on the use of microorganisms to estimate TsD. In the current study, the succession change of microbial community in saliva with different TsD values was explored to discern the microbial markers related to TsD of saliva. We gathered saliva samples from six unrelated healthy Han individuals living in Guizhou, China and exposed these samples to indoor conditions at six time points (0, 1, 3, 7, 15, and 28 days). Temporal changes of microbial compositions in these samples were investigated by 16S rRNA sequencing (V3-V4 regions). By assessing temporal variation patterns of microbial abundance at the genus level, four bacteria (Brucella, Prevotella, Pseudomonas, and Fusobacterium) were observed to show good time dependence in these samples. In addition, the hierarchical clustering and principal co-ordinates analysis results revealed that these saliva samples could be classified into t-short (≤7 days) and t-long (>7 days) groups. In the end, the random forest model was developed to predict the TsD of these samples. For the model, the root mean square error, R2, and mean absolute error between predicted and actual TsD values were 1.5213, 0.9851, and 1.1969, respectively. To sum up, we identified TsD-related microbial markers in saliva samples, which could be viewed as valuable markers for inferring the TsD of saliva.

Evaluation of contaminated groundwater for excessive heavy metal presence and its further assessment of the potential risk to public health.

Water plays a significant role in human life. However, the contamination of groundwater by heavy metals (HMs) has profound implications for public health. Industrialization, urbanization, and agricultural activities are turning out to be major causes for the increasing concentration of HMs in rapidly industrializing areas like Rohtak district, Haryana, India. The current study aimed at evaluating and predicting the health hazards associated with the radical rise of HMs in the groundwater of Rohtak district. For this purpose, 45 seasonal-based groundwater samples were collected from five blocks in Rohtak district, namely Kalanaur, Meham, Lakhan Majra, Rohtak City, and Sampla, both during pre- and post-monsoon seasons. Besides physicochemical analysis, these groundwater samples were analyzed for the contamination of HMs. The findings revealed that groundwater samples were relatively more contaminated during the post-monsoon period rather than pre-monsoon. The water quality index (WQI), devised to classify water quality into specific classes, depicted the Kalanaur region as "very poor." Another index named the HM pollution index (HPI) denoted the levels of HMs and categorized Kalanaur as most deteriorated, followed by Meham, Lakhan Majra, Sampla, and Rohtak City. Additionally, principal component analysis (PCA) was employed that showed a significant variation in the distribution pattern of HMs, with the major load being attributed to PC1 and PC2 for both seasons. Pearson's correlation analysis indicated a significant association of pH (R2 = 0.917) with HMs (specifically for Cd and Cr). In terms of health risk assessment, carcinogenic human health risk due to Pb and Cr was found to be higher in children than adults. Non-carcinogenic risk, indicative of harmful human health effects, apart from cancer, was calculated in terms of hazard quotient (HQ) and hazard index (HI). Results of the same, designated "children" as a vulnerable category compared with "adults," especially in the Kalanaur, Sampla, and Rohtak City blocks of the study area. The results thus reiterated that Kalanaur is the most contaminated block among the five blocks chosen and should be given urgent attention. The study holds importance as it provides a framework regarding the methodology that should be adapted for the evaluation, management, and protection of groundwater at a regional level, which could further be replicated by environmentalists and hydrogeologists across the world. PRACTITIONER POINTS: Water logging is one of the most common problems in Kalanaur block of Rohtak district, responsible for causing groundwater pollution. Cadmium and lead pollution was prevalent in Rohtak due to electroplating industries, paint industry, automobile sector, and industrial discharge. Bioremediation is one of the suitable techniques that can be used for the treatment of groundwater that involves the use of microorganisms. Efficient use of groundwater resources is necessary for sustainable development.

Clay-polymer hybrid hydrogels in the vanguard of technological innovations for bioremediation, metal biorecovery, and diverse applications.

Polymeric hydrogels are among the most studied materials due to their exceptional properties for many applications. In addition to organic and inorganic-based hydrogels, "hybrid hydrogels" have been gaining significant relevance in recent years due to their enhanced mechanical properties and a broader range of functionalities while maintaining good biocompatibility. In this sense, the addition of micro- and nanoscale clay particles seems promising for improving the physical, chemical, and biological properties of hydrogels. Nanoclays can contribute to the physical cross-linking of polymers, enhancing their mechanical strength and their swelling and biocompatibility properties. Nowadays, they are being investigated for their potential use in a wide range of applications, including medicine, industry, and environmental decontamination. The use of microorganisms for the decontamination of environments impacted by toxic compounds, known as bioremediation, represents one of the most promising approaches to address global pollution. The immobilization of microorganisms in polymeric hydrogel matrices is an attractive procedure that can offer several advantages, such as improving the preservation of cellular integrity, and facilitating cell separation, recovery, and transport. Cell immobilization also facilitates the biorecovery of critical materials from wastes within the framework of the circular economy. The present work aims to present an up-to-date overview on the different "hybrid hydrogels" used to date for bioremediation of toxic metals and recovery of critical materials, among other applications, highlighting possible drawbacks and gaps in research. This will provide the latest trends and advancements in the field and contribute to search for effective bioremediation strategies and critical materials recovery technologies.

Isolation of Aerobic Heterotrophic Bacteria from a Microbial Mat with the Ability to Grow on and Remove Hexavalent Chromium through Biosorption and Bioreduction.

Water pollution with toxic hexavalent chromium, Cr(VI), is an environmental threat that has a direct impact on living organisms. The use of microorganisms from microbial mats to remove Cr(VI) has scarcely been investigated. Here, we isolated aerobic heterotrophic bacteria from a Cr-polluted microbial mat found in a mining site in Oman, and investigated their ability to remove Cr(VI), and the underlying mechanism(s) of removal. All isolates fell phylogenetically into the genera Enterobacter, Bacillus, and Cupriavidus, and could completely remove 1 mg L-1 Cr(VI) in 6 days. The strains could tolerate up to 2000 mg L-1 Cr(VI), and exhibited the highest Cr(VI) removal rate at 100 ± 9 mg L-1 d-1. Using scanning electron microscopy (SEM) coupled with elemental analysis, the strains were shown to adsorb Cr(VI) at their cell surfaces. The functional groups OH, NH2, Alkyl, Metal-O, and Cr(VI)-O were involved in the biosorption process. In addition, the strains were shown to reduce Cr(VI) to Cr(III) with the involvement of chromate reductase enzyme. We conclude that the aerobic heterotrophic bacteria isolated from Cr-polluted microbial mats use biosorption and bioreduction processes to remove Cr(VI) from wastewater.

Production and evaluation of new microbic strains on zucchini (Cucurbita pepo L.) plants and control of Powdery mildew and Cladosporiosis

Research objective: The main objective of this article is to report the results obtained from the use of new microbial strains on vegetable plants. In particular, the article will deal with two important topics: i) the study of the effect of microorganisms on the biomass of vegetable plants; ii) the possible control of mortality due to diseases such as powdery mildew and Cladosporiosis. The information reported in this research work can support the design of cropping systems in which agricultural sustainability is fundamental due to the presence of microorganisms with biostimulating activity and as a possible alternative to synthetic plant protection products. Materials and Methods: The plants were grown in pots under controlled conditions; 30 seedlings per thesis, divided into 3 replications of 10 plants each, were planted in early February 2024. The plants used in the trial were Cucurbita pepo L.. The six experimental groups in cultivation were: i) group without microorganisms, irrigated with water and previously fertilised substrate; ii) group with Paecilomyces lilacinus, irrigated with water and previously fertilised substrate, (4.5 x 106 spores/ml), 5ml of product sprayed per kg of substrate; iii) group with Azospirillum sp., irrigated with water and previously fertilised substrate, (4 x 108 spores/g), 1g of mixed product per kg of substrate; iv) group with Glomus sp., irrigated with water and previously fertilised substrate, (3 x 109 spores/g), 1g of mixed product per kg of substrate; v) group with Trichoderma viride, irrigated with water and previously fertilised substrate, (3.6 x 108 spores/ml), 5ml of product sprayed per kg of substrate; vi) group with mix Bacillus subtilis, Pseudomonas sp. and Trichoderma viride, irrigated with water and previously fertilised substrate, (2.3 x 108 spores/ml) 5 ml of product sprayed per kg of substrate. On 5 June 2024, plant height, number of leaves, total leaf area per plant (mm2), primary root length (mm), biomass of the aerial and root system, number and weight of fruits, flowers number and the number of plants dead from powdery mildew and cladosporiosis attacks were recorded. Results and Discussion: The experiment showed that the use of of different types of probiotic and plant defence microorganisms can indeed significantly improve the vegetative and root growth of Cucurbita pepo L.. All treatments showed a significant improvement over the untreated control for the agronomic parameters analysed. The Bacillus subtilis, Pseudomonas sp. and Trichoderma viride treatment with a mix of microorganisms was significantly the best in terms of increasing vegetative and root biomass. Improvements were also found in plant height, number of leaves, leaf area and root length. In addition, significant effects were found on the number of flowers and fruits as well as fruit weight. The trial also revealed the significant effect of the products on the control of powdery mildew and Cladosporiosis, in which case the product PL (Paecilomyces lilacinus) was the best on the two diseases. Conclusions: Experiments have shown that the use of microorganisms can significantly improve the growth, vegetative and root biomass of Cucurbita pepo L.. The treatment also offers increased resistance to mortality that can occur in nursery cultivation. A variety of horticultural and ornamental species have already been tested with microorganisms in previous trials, which highlight other interesting and innovative aspects of the use of microorganisms. Due to the importance of using microbial inoculums in plants, the new agricultural experiments are extremely important as they may allow the development of new products for organic and sustainable farming systems and lead to better results.

Benzo(b)fluoranthene and benzo(k)fluoranthene removal by microalgae in the presence of triazine herbicides: Matrix solid-phase dispersion and solid-phase extraction (MSPD/SPE) for HPLC-UV analysis of the different culture components

Over the last decade, human activities in the industrial and agricultural sectors have significantly increased the concentration of persistent and harmful pollutants in aquatic ecosystems. The use of microorganisms is a green strategy for the bio-removal of certain contaminants. However, other pollutants in the same ecosystems can reduce their degrading activity and even affect their survival. Therefore, this study aimed to evaluate the efficiency of benzo(b)fluoranthene (BbF) and benzo(k)fluoranthene (BkF) removal by Selenastrum capricornutum in the presence of triazine herbicides, compounds mainly used in broadleaf weeds. The interest of this work focused on identifying in which of the microalgal components the degrading activity is best evidenced and affected. For this purpose, the use of solid-phase extraction (SPE) and matrix solid-phase dispersion (MSPD) extraction procedures and HPLC-UV analysis allowed the BbF and BkF trace quantification in biomass, liquid medium, and cell lysate separately from cultures exposed to these polycyclic aromatic hydrocarbons (PAHs) alone or with herbicides. The recovery percentages were between 78 and 94 %, good linearity (r2 ≈ 0.99), precision values measured as RSD < 15 %, and limits of detection (LOQs) at levels of ng mL−1 and ng mg−1 were obtained. The individual PAH amounts measured in the components of microalgae cultures show similar removal kinetics (removal percentages: 82–89 %). Likewise, the analysis demonstrated that the removal of PAHs is not affected in the presence of triazine herbicides (atrazine and cyanazine) and with similar removal percentages (79–86 %) compared to those cultures exposed to individual PAHs (74–83 %). These results support the possible real-world applications of PAH removal by extracts from S. capricornutum in aquatic environments contaminated with PAHs and near agriculture areas where triazine herbicides are used.

Bioremediation of Aflatoxin B1 by Meyerozyma guilliermondii AF01 in Peanut Meal via Solid-State Fermentation.

The use of microorganisms to manage aflatoxin contamination is a gentle and effective approach. The aim of this study was to test the removal of AFB1 from AFB1-contaminated peanut meal by a strain of Meyerozyma guilliermondii AF01 screened by the authors and to optimize the conditions of the biocontrol. A regression model with the removal ratio of AFB1 as the response value was established by means of single-factor and response surface experiments. It was determined that the optimal conditions for the removal of AFB1 from peanut meal by AF01 were 75 h at 29 °C under the natural pH, with an inoculum of 5.5%; the removal ratio of AFB1 reached 69.31%. The results of simulating solid-state fermentation in production using shallow pans and fermentation bags showed that the removal ratio of AFB1 was 68.85% and 70.31% in the scaled-up experiments, respectively. This indicated that AF01 had strong adaptability to the environment with facultative anaerobic fermentation detoxification ability. The removal ratio of AFB1 showed a positive correlation with the growth of AF01, and there were no significant changes in the appearance and quality of the peanut meal after fermentation. This indicated that AF01 had the potential to be used in practical production.

Role of Bacteria in Plant Nutrient Mobilization: A Review

Plant roots are the site of dynamic and complex interactions between a variety of microorganisms, such as fungi, bacteria, and archaea. Plant Growth-Promoting Rhizobacteria (PGPR) is one of those that are important for improving the health and growth of plants. Bacteria are among the most abundant and diverse microorganisms in the rhizosphere. These bacteria contribute to various processes, including nitrogen fixation, phosphate solubilization, and production of plant growth-promoting substances, thereby enhancing plant nutrient uptake and growth. Fungi are another important component of the rhizosphere microbiota. These microbes are used as bioinoculants in the agricultural field, replacing the traditional use of pesticides. Bioinoculants do not show any detrimental impact on the soil's plant and animal life as they are eco-friendly, highly efficient, and can be utilized as bio-pesticides that do not have any harmful influence on plant products. Understanding the composition and functions of rhizosphere microbiota is crucial for developing sustainable agricultural practices that harness the beneficial interactions between plants and microorganisms to enhance soil fertility and crop productivity while minimizing environmental impacts. This review examines the emerging use of microorganisms in the agricultural field, which can replace the chemical fertilizers that are proven hazardous if used extensively over crops, specifically regarding the important micronutrients required by the plant. The current study addresses the gap in the effectiveness of these microorganisms as bio-inoculants in the rhizosphere and future aspects of the microbes for crop productivity.

Eco-Restorative Solutions: Unveiling Bioremediation's Impact on Water Quality Enhancement

As a result of the world's growing industrialization and urbanization, developing nations have the densest populations worldwide. Due to numerous anthropogenic activities, this population growth has resulted in the generation of huge quantities of waste and reclaimed water. The main challenge is creating approaches so that they support wastewater treatment. Therefore, bioremediation is regarded as one of the most environmentally friendly, economical, safer and cleanest technologies for cleaning up sites contaminated with a variety of contaminants, including heavy metals, inorganic pollutants, organic pollutants, oil spill, dye and pesticides. The use of microorganisms found in nature, such as bacteria, fungus, and microalgae has emerged as an ecofriendly method. Using their unique molecular biodegradation pathways, novel bioremediation organisms offer innovative and useful insights. Enzymes, metabolites, and other bioactive chemicals produced by bacteria involved in water treatment can be identified primarily through the use of metagenomics techniques. This review speeds up research on the role of bioremediation in water purification while also providing a brief discussion of the environmental effects of water pollution.

WSTĘPNE OKREŚLENIE MOŻLIWOŚCI REDUKCJI NAWOŻENIA AZOTOWEGO POD WPŁYWEM PREPARATÓW BAKTERYJNYCH W UPRAWIE TRITICUM AESTIVUM L.

The use of microorganisms in agriculture is attracting increasing interest. Thus, the state of knowledge on this issue and biotechnological advances are significantly increasing. A field research was conducted during the 2022–2023 growing season to evaluate the influence of the combined application of bacterial formulation and mineral nitrogen fertilization on grain and straw yield of winter wheat (Triticum aestivum L.) and the structure of the obtained yield. The factors of the conducted field experiment were bacterial formulations: control (no application of bacterial formulations), I – Azotobacter and Arthrobacter, II – Bacillus subtillis, Bacillus megaterium, Bacillus azotofixans, III – Bacillus azotofixans; B – mineral nitrogen fertilization: control (no mineral nitrogen fertilization), 43 kg N·ha−1, 86 kg N·ha−1, 130 kg N·ha−1. Research was conducted demonstrating the most favorable effects after applying a bacterial formulation containing Azotobacter and Arthrobacter bacteria. It was statistically significant increase in grain yield by an average of 17%, number of ears per m2 by 15%, ear length by 5% and thousand grain weight by 3% The application of other formulations also caused an increase in the analyzed traits, but they were lower than those given for Azotobacter and Arthrobacter bacteria. A gradual increase in the level of mineral nitrogen fertilization also had a positive effect on the analyzed traits. The research conducted in the field found a possible reduction in mineral nitrogen fertilization under the conditions of the conducted experiment by about 33% without yield losses when using a bacterial formulation containing Azotobacter and Arthrobacter. Thus, it is appropriate to recommend the use of these bacteria in winter wheat cultivation, but due to the possible variable effectiveness of application under different soil and climatic conditions, the presented research should be continued in different areas both in wheat and other crops.

Multiple Perspectives of Study on the Potential of Bacillus amyloliquefaciens JB20221020 for Alleviating Nutrient Stress in Lettuce.

Soil nutrient deficiency has become a key factor limiting crop growth. Plant growth-promoting rhizobacteria (PGPR) are vital in resisting abiotic stress. In this study, we investigated the effects of inoculation with Bacillus amyloliquefaciens JB20221020 on the physiology, biochemistry, rhizosphere microorganisms, and metabolism of lettuce under nutrient stress. Pot experiments showed that inoculation with B. amyloliquefaciens JB20221020 significantly promoted lettuce growth under nutrient deficiency. At the same time, the activities of the antioxidant enzymes superoxide dismutase, peroxidase, and catalase and the content of proline increased, and the content of Malondialdehyde decreased in the lettuce inoculated with B. amyloliquefaciens JB20221020. Inoculation with B. amyloliquefaciens JB20221020 altered the microbial community of the rhizosphere and increased the relative abundances of Myxococcales, Deltaproteobacteria, Proteobacteria, Devosia, and Verrucomicrobia. Inoculation also altered the rhizosphere metabolism under nutrient deficiency. The folate metabolism pathway was significantly enriched in the Kyoto Encyclopedia of Genes and Genomes enrichment analysis. This study explored the interaction between plants and microorganisms under nutrient deficiency, further explained the critical role of rhizosphere microorganisms in the process of plant nutrient stress, and provided a theoretical basis for the use of microorganisms to improve plant resistance.

Control biológico contra Fusarium sp. en plantas de uchuva (Physalis peruviana L.) a nivel de invernadero mediante aplicación combinada de Trichoderma sp. y Bacillus sp.

Contextualization: The production of cape gooseberry (Physalis peruviana L.), an exotic fruit of great commercial importance in Colombia, has been limited by the presence of Fusarium sp. Which causes losses of up to 40% of production; this pathogen is mainly controlled with chemical synthesis products. Knowledge gap: The individual use of microorganisms for biological control has become a useful strategy to reduce the impact caused by Fusarium sp. However, its activity is limited in the field, and therefore it is necessary to carry out consortium combinations of different native microbial genera as a promising tool for biological control. Purpose: To evaluate the antagonistic activity of the combined application of Trichoderma sp. and Bacillus sp. as biocontrollers of Fusarium sp. at greenhouse level in cape gooseberry (Physalis peruviana L.) Methodology: Microorganisms were isolated from soil samples and plant material from a cape gooseberry crop. Isolates consistent with Bacillus sp. and Trichoderma sp. were confronted in vitro conditions to determine the percentage of inhibition over three Fusarium sp. that showed pathogenicity in cape gooseberry seeds according to their germination and root length. The in vivo antagonist activity was tested individually and in a consortium of Bacillus sp. and Trichoderma sp. that most inhibited Fusarium sp. with a higher pathogenicity index. Additionally, these isolates were identified by morphological, molecular and phylogenetic techniques. Results and conclusions: Seven native isolates consistent with Bacillus sp. with inhibitory activity against three Fusarium sp. were obtained. The bacterial isolate IB4B (identified as Bacillus sp.) registered the highest percentage of inhibition (48%), and TV1 was the fungus with the highest activity (64%) although. It did not differ statistically from TV2 (identified as Trichoderma asperellum). The pathogenicity test indicated that UCMV21 (identified as Fusarium oxysporum) inhibited the germination of 58% of the evaluated seeds. In the in vivo tests on cape gooseberry seedlings, UCMV21 presented low pathogenicity by developing few symptoms of vascular wilt. However, treatments with the Bacillus sp. and Trichoderma sp., achieved control of the pathogen and improved the root length of the seedlings.