MINIstock: Model for INsect Inclusion in sustainable agriculture: USDA-ARS's research approach to advancing insect meal development and inclusion in animal diets.

Animal agriculture is under pressure to increase efficiency, sustainability, and innovation to meet the demands of a rising global population while decreasing adverse environmental effects. Feed cost and availability are 2 of the biggest hurdles to sustainable production. Current diets depend on sources of grain and animal byproduct protein for essential amino acids which have limited sustainability. Insects have arisen as an attractive, sustainable alternative protein source for animal diets due to their favorable nutrient composition, low space and water requirements, and natural role in animal diets. Additionally, insects are capable of bioremediating waste streams including agricultural and food waste, manure, and plastics helping to increase their sustainability. The insect rearing industry has grown rapidly in recent years and shows great economic potential. However, state-of-the-art research is urgently needed to overcome barriers to adoption in commercial animal diets such as regulatory restrictions, production scale issues, and food safety concerns. To address this need, the USDA Agricultural Research Service "MINIstoc: Model for INsect Inclusion" project was created to bring together diverse scientists from across the world to synergistically advance insect meal production and inclusion in animal diets. Here, we provide a short review of insects as feed while describing the MINIstock project which serves as the inspiration for the Journal of Economic Entomology Special Collection "Insects as feed: sustainable solutions for food waste and animal production practices."

Staphylococcus arlettae mediated defense mechanisms and metabolite modulation against arsenic stress in Helianthus annuus.

Introduction: Arsenate, a metalloid, acting as an analog to phosphate, has a tendency to accumulate more readily in plant species, leading to adverse effects. Methods: In the current study, sunflower seedlings were exposed to 25, 50 and 100 ppm of the arsenic. Results: Likewise, a notable reduction (p<0.05) was observed in the relative growth rate (RGR) by 4-folds and net assimilation rate (NAR) by 75% of Helianthus annuus when subjected to arsenic (As) stress. Nevertheless, the presence of Staphylococcus arlettae, a plant growth-promoting rhizobacterium with As tolerance, yielded an escalation in the growth of H. annuus within As-contaminated media. S. arlettae facilitated the conversion of As into a form accessible to plants, thereby, increasing its uptake and subsequent accumulation in plant tissues. S. arlettae encouraged the enzymatic antioxidant systems (Superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX) and catalase (CAT)) and non-enzymatic antioxidants (flavonoids, phenolics, and glutathione) in H. annuus seedlings following substantial As accumulation. The strain also induced the host plant to produce osmolytes like proline and sugars, mitigating water loss and maintaining cellular osmotic balance under As-induced stress. S. arlettae rectified imbalances in lignin content, reduced high malonaldehyde (MDA) levels, and minimized electrolyte leakage, thus counteracting the toxic impacts of the metal. Conclusion: The strain exhibited the capability to concurrently encourage plant growth and remediate Ascontaminated growth media through 2-folds rate of biotransformation and bio-mobilization.

Microbial electrochemical Cr(VI) reduction in a soil continuous flow system.

Microbial electrochemical technologies represent innovative approaches to contaminated soil and groundwater remediation and provide a flexible framework for removing organic and inorganic contaminants by integrating electrochemical and biological techniques. To simulate in situ microbial electrochemical treatment of groundwater plumes, this study investigates Cr(VI) reduction within a bioelectrochemical continuous flow (BECF) system equipped with soil-buried electrodes, comparing it to abiotic and open-circuit controls. Continuous-flow systems were tested with two chromium-contaminated solutions (20-50 mg Cr(VI)/L). Additional nutrients, buffers, or organic substrates were introduced during the tests in the systems. With an initial Cr(VI) concentration of 20 mg/L, 1.00 mg Cr(VI)/(L day) bioelectrochemical removal rate in the BECF system was observed, corresponding to 99.5% removal within nine days. At the end of the test with 50 mg Cr(VI)/L (156 days), the residual Cr(VI) dissolved concentration was two orders of magnitude lower than that in the open circuit control, achieving 99.9% bioelectrochemical removal in the BECF. Bacteria belonging to the orders Solirubrobacteriales, Gaiellales, Bacillales, Gemmatimonadales, and Propionibacteriales characterized the bacterial communities identified in soil samples; differently, Burkholderiales, Mycobacteriales, Cytophagales, Rhizobiales, and Caulobacterales characterized the planktonic bacterial communities. The complexity of the microbial community structure suggests the involvement of different microorganisms and strategies in the bioelectrochemical removal of chromium. In the absence of organic carbon, microbial electrochemical removal of hexavalent chromium was found to be the most efficient way to remove Cr(VI), and it may represent an innovative and sustainable approach for soil and groundwater remediation. Integr Environ Assess Manag 2024;00:1-17. © 2024 The Author(s). Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Remediation of phenanthrene contaminated soil by persulphate coupled with Pseudomonas aeruginosa GZ7 based on oxidation prediction model.

Chemical oxidation coupled with microbial remediation has attracted widespread attention for the removal of polycyclic aromatic hydrocarbons (PAHs). Among them, the precise evaluation of the feasible oxidant concentration of PAH-contaminated soil is the key to achieving the goal of soil functional ecological remediation. In this study, phenanthrene (PHE) was used as the target pollutant, and Fe2+-activated persulphate (PS) was used to remediate four types of soils. Linear regression analysis identified the following important factors influencing remediation: PS dosage and soil PHE content for PHE degradation, Fe2+ dosage, hydrolysable nitrogen (HN), and available phosphorus for PS decomposition. A comprehensive model of "soil characteristics-oxidation conditions-remediation effect" with a high predictive accuracy was constructed. Based on model identification, Pseudomonas aeruginosa GZ7, which had high PAHs degrading ability after domestication, was further applied to coupling repair remediation. The results showed that the optimal PS dose was 0.75% (w/w). The response relationship between soil physical, chemical, and biological indicators at the intermediate interface and oxidation conditions was analysed. Coupled remediation effects were clarified using microbial diversity sequencing. The introduction of Pseudomonas aeruginosa GZ7 stimulated the relative abundance of Cohnella, Enterobacter, Paenibacillus, and Bacillus, which can promote material metabolism and energy transformation during remediation.

Diversity of hydrocarbon-degrading bacteria in mangroves rhizosphere as an indicator of oil-pollution bioremediation in mangrove forests.

Mangrove ecosystems, characterized by high levels of productivity, are susceptible to anthropogenic activities, notably oil pollution arising from diverse origins including spills, transportation, and industrial effluents. Owing to their role in climate regulation and economic significance, there is a growing interest in developing mangrove conservation strategies. In the Arabian Gulf, mangroves stand as the sole naturally occurring green vegetation due to the region's hot and arid climate. However, they have faced persistent oil pollution for decades. This review focuses on global mangrove distribution, with a specific emphasis on Qatar's mangroves. It highlights the ongoing challenges faced by mangroves, particularly in relation to the oil industry, and the impact of oil pollution on these vital ecosystems. It outlines major oil spill incidents worldwide and the diverse hydrocarbon-degrading bacterial communities within polluted areas, elucidating their potential for bioremediation. The use of symbiotic interactions between mangrove plants and bacteria offers a more sustainable, cost-effective and environmentally friendly alternative. However, the success of these bioremediation strategies depends on a deep understanding of the dynamics of bacterial communities, environmental factors and specific nature of the pollutants.

Chromium removal by microbial mats: understanding the effect of salinity and pH.

Environmental contamination by chromium represents a serious public health problem. Therefore, it is crucial to develop and optimize remediation technologies to reduce its concentration in the environment. The aims of this study were to evaluate the uptake of chromium by live and complete microbial mats in experimental mesocosms under different pH and salinity conditions to understand how these factors affect the microphytobenthic community and, consequently, how chromium removal process is influenced. Microbial mats from the estuarine environment were exposed to 15 mg Cr/L under different pH (2, 4, and 8) and salinity (2, 15, and 33) conditions. Salinity, redox potential, and pH were measured throughout the trial in solutions and in microbial mats, while total Cr determinations were performed at the end of the assay. The results demonstrated that the removal efficiency of Cr by microbial mats was significantly improved in solutions at pH 2, remaining unaffected by variations in salinity. Notably, both cyanobacteria and diatoms showed remarkable resistance to Cr exposure under all conditions tested, highlighting their exceptional adaptability. Microbial mats have proved to be effective filters for reducing the concentration of chromium in aqueous solutions with varying pH and salinity levels.

Influence of humic acid on the p-tert-Butylphenol removal efficiency by Spirodela polyrhiza-Tas13 association.

Plant-microbe remediation technique is considered as a promising technology in removal of organic pollutants and its remediation efficiency is largely affected by a variety of surrounding environmental factors. Humic acid (HA) is the complex organic substance ubiquitous in environment, which characterized by its surfactant-like micelle microstructure and various reaction activity. In our study, a plant-microbe association with high p-tert-Butylphenol (PTBP) degradation potential constructed by Spirodela polyrhiza and Sphingobium phenoxybenzoativorans Tas13 has been used, and the influence of HA on the PTBP degradation efficiency of S. polyrhiza-Tas13 association was investigated. The result showed that the presence of HA greatly improved PTBP removal efficiency of S. polyrhiza-Tas13. The reason accounted for this may be due to the presence of HA promoted bacterial cell propagation, altered bacterial cell wall permeability, increased catechol 2,3-dioxygenase (C23O) enzyme activity of strain Tas13, rather than increasing the colonization ability of strain Tas13 on to the root surface. This study will greatly facilitate the application of aquatic plant-microbe association in environmental remediation.

An ecofriendly approach to bioremediate nickel oxide nanoparticles using a macrofungus, Pleurotus fossulatus.

Nowadays, nickel oxide nanoparticles are in great demands owing to their use in many sectors. These nanoparticles may release into aquatic environment from different industries and cause negative effect on aquatic flora and fauna. Therefore, an effective and efficient method is required to remove these nanoparticles from contaminated water. Hence, the aim of this study was to bioremediate nickel oxide nanoparticles using a macrofungus, Pleurotus fossulatus, and to analyze its impact on fungal physiology. For this purpose, fungal spawns were inoculated in malt dextrose agar media containing different concentrations of nickel oxide nanoparticles (24 mg/l, 48 mg/l, and 100 mg/l) as well as control group (having no nickel oxide nanoparticles) and allowed to grow for a period of 20 days. Fungal mycelia as well as media were collected at different time intervals (5th day, 10th day, 15th day, and 20th day) for evaluation of Ni concentration and different biochemical parameters. Ni removal efficiency of P. fossulatus from media was found to be highest in 48 mg/l (66.98%) followed by 24 mg/l (60.83%) and 100 mg/l (18.03%), respectively. Increased level of metallothionein, lipid peroxidation, activity of different antioxidant enzymes (superoxide dismutase, catalase, glutathione s transferase, glutathione reductase), activity of ligninolytic enzymes (laccase, lignin peroxidase, manganese peroxidase), and shift in FTIR spectra were also reported in mycelia cultured in malt dextrose agar media containing nickel oxide nanoparticles. This study suggests that P. fossulatus has great efficiency to remediate nanoparticles from contaminated water and it can be utilized as potential agent in wastewater treatment plants by different industries.

Synergistic interactions in core microbiome Rhizobiales accelerate 1,4-dioxane biodegradation.

Next-generation sequencing (NGS) has revolutionized taxa identification within contaminant-degrading communities. However, uncovering a core degrading microbiome in diverse polluted environments and understanding its associated microbial interactions remains challenging. In this study, we isolated two distinct microbial consortia, namely MA-S and Cl-G, from separate environmental samples using 1,4-dioxane as a target pollutant. Both consortia exhibited a persistent prevalence of the phylum Proteobacteria, especially within the order Rhizobiales. Extensive analysis confirmed that Rhizobiales as the dominant microbial population (> 90 %) across successive degradation cycles, constituting the core degrading microbiome. Co-occurrence network analysis highlighted synergistic interactions within Rhizobiales, especially within the Shinella and Xanthobacter genera, facilitating efficient 1,4-dioxane degradation. The enrichment of Rhizobiales correlated with an increased abundance of essential genes such as PobA, HpaB, ADH, and ALDH. Shinella yambaruensis emerged as a key degrader in both consortia, identified through whole-genome sequencing and RNA-seq analysis, revealing genes implicated in 1,4-dioxane degradation pathways, such as PobA and HpaB. Direct and indirect co-cultivation experiments confirmed synergistic interaction between Shinella sp. and Xanthobacter sp., enhancing the degradation of 1,4-dioxane within the core microbiome Rhizobiales. Our findings advocate for integrating the core microbiome concept into engineered consortia to optimize 1,4-dioxane bioremediation strategies.

Bioremediation of organic pollutants by laccase-metal-organic framework composites: A review of current knowledge and future perspective.

Immobilized laccases are widely used as green biocatalysts for bioremediation of phenolic pollutants and wastewater treatment. Metal-organic frameworks (MOFs) show potential application for immobilization of laccase. Their unique adsorption properties provide a synergic effect of adsorption and biodegradation. This review focuses on bioremediation of wastewater pollutants using laccase-MOF composites, and summarizes the current knowledge and future perspective of their biodegradation and the enhancement strategies of enzyme immobilization. Mechanistic strategies of preparation of laccase-MOF composites were mainly investigated via physical adsorption, chemical binding, and de novo/co-precipitation approaches. The influence of architecture of MOFs on the efficiency of immobilization and bioremediation were discussed. Moreover, as sustainable technology, the integration of laccases and MOFs into wastewater treatment processes represents a promising approach to address the challenges posed by industrial pollution. The MOF-laccase composites can be promising and reliable alternative to conventional techniques for the treatment of wastewaters containing pharmaceuticals, dyes, and phenolic compounds. The detailed exploration of various immobilization techniques and the influence of MOF architecture on performance provides valuable insights for optimizing these composites, paving the way for future advancements in environmental biotechnology. The findings of this research have the potential to influence industrial wastewater treatment and promoting cleaner treatment processes and contributing to sustainability efforts.

Halophilic archaea as tools for bioremediation technologies.

Haloarchaea are extremophilic microorganisms belonging to the Archaea domain that require high salt concentrations to be alive, thus inhabiting ecosystems like salty ponds, salty marshes, or extremely salty lagoons. They are more abundantly and widely distributed worldwide than initially expected. Most of them are grouped into two families: Halobacteriaceae and Haloferacaceae. The extreme conditions under which haloarchaea survive contribute to their metabolic and molecular adaptations, thus making them good candidates for the design of bioremediation strategies to treat brines, salty water, and saline soils contaminated with toxic compounds such as nitrate, nitrite, oxychlorates such as perchlorate and chlorate, heavy metals, hydrocarbons, and aromatic compounds. New advances in understanding haloarchaea physiology, metabolism, biochemistry, and molecular biology suggest that biochemical pathways related to nitrogen and carbon, metals, hydrocarbons, or aromatic compounds can be used for bioremediation proposals. This review analyses the novelty of the most recent results showing the capability of some haloarchaeal species to assimilate, modify, or degrade toxic compounds for most living beings. Several examples of the role of these microorganisms in the treatment of polluted brine or salty soils are also discussed in connection with circular economy-based processes. KEY POINTS: • Haloarchaea are extremophilic microorganisms showing genuine metabolism • Haloarchaea can metabolise compounds that are highly toxic to most living beings • These metabolic capabilities are useful for designing soil and water bioremediation strategies.

Unlocking Cd(II) biosorption potential of Candida tropicalis XTA 1874 for sustainable wastewater treatment.

Cd(II) is a potentially toxic heavy metal having carcinogenic activity. It is becoming widespread in the soil and groundwater by various natural and anthropological activities. This is inviting its immediate removal. The present study is aimed at developing a Cd(II) resistant strain isolated from contaminated water body and testing its potency in biological remediation of Cd(II) from aqueous environment. The developed resistant strain was characterized by SEM, FESEM, TEM, EDAX, FT-IR, Raman Spectral, XRD and XPS analysis. The results depict considerable morphological changes had taken place on the cell surface and interaction of Cd(II) with the surface exposed functional groups along with intracellular accumulation. Molecular contribution of critical cell wall component has been evaluated. The developed resistant strain had undergone Cd(II) biosorption study by employing adsorption isotherms and kinetic modeling. Langmuir model best fitted the Cd(II) biosorption data compared to the Freundlich one. Cd(II) biosorption by the strain followed a pseudo second order kinetics. The physical parameters affecting biosorption were also optimized by employing response surface methodology using central composite design. The results depict remarkable removal capacity 75.682 ± 0.002% of Cd(II) by the developed resistant strain from contaminated aqueous medium using 500 ppm of Cd(II). Quantitatively, biosorption for Cd(II) by the newly developed resistant strain has been increased significantly (p < 0.0001) from 4.36 ppm (non-resistant strain) to 378.41 ppm (resistant strain). It has also shown quite effective desorption capacity 87.527 ± 0.023% at the first desorption cycle and can be reused effectively as a successful Cd(II) desorbent up to five cycles. The results suggest that the strain has considerable withstanding capacity of Cd(II) stress and can be employed effectively in the Cd(II) bioremediation from wastewater.

Using PyCaret to model Chlorella vulgaris's growth response to salinity and oil contamination for crude oil bioremediation.

Crude oil spills significantly impact aquatic ecosystems, necessitating innovative remediation strategies. Microalgae-based bioremediation, particularly with Chlorella vulgaris, offers a promising solution. This study introduces a novel framework that evaluates the combined effects of selected environmental stressors on microalgal adaptability, advancing beyond traditional isolated factor analyses. By integrating a factorial experimental design with a machine learning approach using PyCaret AutoML and SHAP values, we provide a detailed examination of how crude oil concentration, salinity, and exposure duration affect C. vulgaris growth. The Extra Trees Regressor model emerged as highly accurate in predicting biomass concentration, a crucial adaptability indicator, achieving an MAE of 0.0202, RMSE of 0.029, and an R² of 0.8875. SHAP analysis highlighted salinity and crude oil as significant growth influencers, with exposure duration playing a minor role. Notably, C. vulgaris exhibited more sensitivity to salinity than to crude oil, indicating potential high-salinity challenges but also a strong tolerance to oil pollutants. These findings enhance our understanding of microalgal responses in polluted environments and suggest improved bioremediation approaches for saline waters affected by oil spills, leveraging the synergy of environmental factors and machine learning insights.

Pseudomonas aeruginosa PR23 isolated from oil contaminated soil tolerate and degrades mixture of polyaromatic hydrocarbons and express novel proteins.

Pseudomonas aeruginosa PR23 isolated from the hydrocarbon contaminated soil can tolerate and degrade mixture of polyaromatic hydrocarbons (PAHs) at an initial concentration of 1300 ppm. The degradation and intermediates formed were assessed by gas chromatography-mass spectrometry (GC-MS) analysis. The isolated strain was able to degrade 59.2% of the mixture of PAHs in 3 days and 71.6% by day 15. Effect of PAHs on protein expression in Pseudomonas aeruginosa PR23 was studied using nano LC-MS/MS. Thirty-six proteins showed a more than 2-fold increase in expression in the presence of mixture of PAHs. Out of these proteins, 7 proteins have been reported for their role in degradation of naphthalene, phenanthrene, and pyrene. The data revealed the presence of 16 proteins that were uniquely expressed in the presence of mixture of PAHs. A twin-arginine translocation signal peptide (Tat system), known for the transportation of folded proteins across the cell membrane, showed more than 8-fold increased expression in the presence of mixture of PAHs. These results indicate that the isolated strain adopts the conditions in the presence of mixture of PAHs by modulating its metabolic and physiological processes. These findings suggest that Pseudomonas aeruginosa PR23 may be a suitable candidate for use in the development of strategies for bioremediation of mixtures of PAHs.

Current paradigms and future challenges in harnessing gut bacterial symbionts of insects for biodegradation of plastic wastes.

The ubiquitous incorporation of plastics into daily life, coupled with inefficient recycling practices, has resulted in the accumulation of millions of metric tons of plastic waste, that poses a serious threat to the Earth's sustainability. Plastic pollution, a global problem, disrupts the ecological balance and endangers various life forms. Efforts to combat plastic pollution are underway, with a promising avenue being biological degradation facilitated by certain insects and their symbiotic gut microorganisms, particularly bacteria. This review consolidates existing knowledge on plastic degradation by insects and their influence on gut microbiota. Additionally, it delves into the potential mechanisms employed by insects in symbiosis with gut bacteria, exploring the bioconversion of waste plastics into value-added biodegradable polymers through mineralization. These insights hold significant promise for the bio-upcycling of plastic waste, opening new horizons for future biomanufacturing of high-value chemicals from plastic-derived compounds. Finally, we weigh the pros and cons of future research endeavors related to the bioprospection of plastic-degrading bacteria from underexplored insect species. We also underscore the importance of bioengineering depolymerases with novel characteristics, aiming for their application in the remediation and valorization of waste plastics.

A synthetic bacterial consortium improved the phytoremediation efficiency of ryegrass on polymetallic contaminated soil.

Polymetallic contamination of soils caused by mining activities seriously threatens soil fertility, biodiversity and human health. Bioremediation is thought to be of low cost and has minimal environmental risk but its effectiveness needs to be improved. This study aimed to identify the combined effect of plant growth and microbial strains with different functions on the enhancement of bioremediation of polymetallic contaminated soil. The microbiological mechanism of bioremediation was explored by amplicon sequencing and gene prediction. Soil was collected from polymetallic mine wastelands and a non-contaminated site for use in a pot experiment. Remediation efficiency of this method was evaluated by planting ryegrass and applying a mixed bacterial consortium comprising P-solubilizing, N-fixing and SO4-reducing bacteria. The plant-microbe joint remediation method significantly enhanced the above-ground biomass of ryegrass and soil nutrient contents, and at the same time reduced the content of heavy metals in the plant shoots and soil. The application of the composite bacterial inoculum significantly affected the structure of soil bacterial communities and increased the bacterial diversity and complexity, and the stability of co-occurrence networks. The relative abundance of the multifunctional genera to which the strains belonged showed a significant positive correlation with the soil nutrient content. Genera related to carbon (C), nitrogen (N), phosphorus (P), and sulphur (S) cycling and heavy metal resistance showed an up-regulation trend in heavy metal-contaminated soils after the application of the mixed bacterial consortium. Also, bacterial strains with specific functions in the mixed consortium regulated the expression of genes involved in soil nutrient cycling, and thus assisted in making the soil self-sustainable after remediation. These results suggested that the remediation of heavy metal-contaminated soil needs to give priority to the use of multifunctional bacterial agents.

Design of a two functional permeable reactive barrier for synergistic enzymatic and microbial bioremediation of phenol-contaminated waters: laboratory column evaluation : Enzymatic and microbial bioremediation of phenol in a bilayer permeable reactive barrier.

The present study aimed to develop a system using a combination of enzymatic and microbial degradation techniques for removing phenol from contaminated water. In our prior research, the HRP enzyme extracted from horseradish roots was utilized within a core-shell microcapsule to reduce phenolic shock, serving as a monolayer column. To complete the phenol removal process, a second column containing degrading microorganisms was added to the last column in this research. Phenol-degrading bacteria were isolated from different microbial sources on a phenolic base medium. Additionally, encapsulated calcium peroxide nanoparticles were used to provide dissolved oxygen for the microbial population. Results showed that the both isolated strains, WC1 and CC1, were able to completely remove phenol from the contaminated influent water the range within 5 to 7 days, respectively. Molecular identification showed 99.8% similarity for WC1 isolate to Stenotrophomonas rizophila strain e-p10 and 99.9% similarity for CC1 isolate to Bacillus cereus strain IAM 12,605. The results also indicated that columns using activated sludge as a microbial source had the highest removal rate, with the microbial biofilm completely removing 100% of the 100 mg/L phenol concentration in contaminated influent water after 40 days. Finally, the concurrent use of core-shell microcapsules containing enzymes and capsules containing Stenotrophomonas sp. WC1 strain in two continuous column reactors was able to completely remove phenol from polluted water with a concentration of 500 mg/L for a period of 20 days. The results suggest that a combination of enzymatic and microbial degrading systems can be used as a new system to remove phenol from polluted streams with higher concentrations of phenol by eliminating the shock of phenol on the microbial population.

The History of Agrobacterium Rhizogenes: From Pathogen to a Multitasking Platform for Biotechnology.

Agrobacterium's journey has been a roller coaster, from being a pathogen to becoming a powerful biotechnological tool. While A. tumefaciens has provided the scientific community with a versatile tool for plant transformation, Agrobacterium rhizogenes has given researchers a Swiss army knife for developing many applications. These applications range from a methodology to regenerate plants, often recalcitrant, to establish bioremediation protocols to a valuable system to produce secondary metabolites. This chapter reviews its discovery, biology, controversies over its nomenclature, and some of the multiple applications developed using A. rhizogenes as a platform.

Synergistic impacts of antibiotics and heavy metals on Hermetia illucens: Unveiling dynamics in larval gut bacterial communities and microbial metabolites.

Hermetia illucens larvae showcases remarkable bioremediation capabilities for both antibiotics and heavy metal contaminants. However, the distinctions in larval intestinal microbiota arising from the single and combined effects of antibiotics and heavy metals remain poorly elucidated. In this study, we delved into the details of larval intestinal bacterial communities and microbial metabolites when exposed to single and combined contaminants of oxytetracycline (OTC) and hexavalent chromium (Cr(VI)). After conversion, single contaminant-spiked substrate showed 75.5% of OTC degradation and 95.2% of Cr(VI) reductiuon, while combined contaminant-spiked substrate exhibited 71.3% of OTC degradation and 93.4% of Cr(VI) reductiuon. Single and combined effects led to differences in intestinal bacterial communities, mainly reflected in the genera of Enterococcus, Pseudogracilibacillus, Gracilibacillus, Wohlfahrtiimonas, Sporosarcina, Lysinibacillus, and Myroide. Moreover, these effects also induced differences across various categories of microbial metabolites, which categorized into amino acid and its metabolites, benzene and substituted derivatives, carbohydrates and its metabolites, heterocyclic compounds, hormones and hormone-related compounds, nucleotide and its metabolites, and organic acid and its derivatives. In particular, the differences induced OTC was greater than that of Cr(VI), and combined effects increased the complexity of microbial metabolism compared to that of single contaminant. Correlation analysis indicated that the bacterial genera, Preudogracilibacillus, Enterococcus, Sporosarcina, Lysinibacillus, Wohlfahrtiimonas, Ignatzschineria, and Fusobacterium exhibited significant correlation with significant differential metabolites, these might be used as indicators for the resistance and bioremediation of OTC and Cr(VI) contaminants. These findings are conducive to further understanding that the metabolism of intestinal microbiota determines the resistance of Hermetia illucens to antibiotics and heavy metals.

Microbial valorization of kraft black liquor for production of platform chemicals, biofuels, and value-added products: A critical review.

The proper treatment and utilization of kraft black liquor, generated from the pulp and paper industry through the kraft pulping method, is required to reduce environmental impacts prior to the final disposal. It also improves the economic performance through the utilization of waste. Microbial valorization appears to demonstrates the dual benefits of waste management and resource recovery by providing an innovative solution to convert kraft black liquor into resource for reuse. A comprehensive review on the microbial valorization of kraft black liquor, describing the role in valorization and management, is still lacking in the literature, forming the rationale of this article. Thus, the present study reviews and systematically discusses the potential of utilizing microorganisms to valorize kraft black liquor as a sustainable feedstock to develop a numerous portfolio of platform chemicals, bioenergy, and other value-added products. This work contributes to sustainability and resource efficiency within the pulp and paper industry. The recent developments in utilization of synthetic biology tools and molecular techniques, including omics approaches for engineering novel microbial strains, for enhancing kraft black liquor valorization has been presented. This review explores how the better utilization of kraft black liquor in the pulp and paper industry contributes to achieving UN Sustainable Development Goals (SDGs), particularly clean water and sanitation (SDG 6) as well as the affordable and clean energy goal (SDG 7). The current review also addresses challenges related to toxicity, impurities, low productivity, and downstream processing that serve as obstacles to the progress of developing highly efficient bioproducts. The new directions for future research efforts to fill the critical knowledge gaps are proposed. This study concludes that by implementing microbial valorization techniques, the pulp and paper industry can transition from a linear to a circular bioeconomy and eco-friendly manage the kraft black liuor. This approach showed to be effective towards resource recovery, while simultaneously minimizing the environmental burden.