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Microalgae and cyanobacteria could play an important role in crop protection, since they produce bioactive substances that promote plant growth and/or trigger the plant resistance mechanisms. The present study focuses on the control of bacterial canker caused by Clavibacter michiganensis subsp. michiganensis on tomato plants by using sonicated extracts from cyanobacteria and microalgae of the genera Leptolyngbya, Nostoc, Chlorella, and Scenedesmus. For the development of this study, 8 strains were firstly tested for their capacity to inhibit the growth of C. michiganensis subsp. michiganensis in vitro, as well as to produce cytokinins and salicylic acid. In order to discard those more phytotoxic strains, the germination index was also estimated in watercress seeds. Scenedesmus-677 and Leptolyngbya-1267 strains were selected in this first phase based on their pesticide and phytostimulant capacity in vitro. Subsequent bioassays on tomato seedlings showed that root application of Scenedesmus-677 could be more aimed at controlling the disease caused by C. michiganensis subsp. michiganensis, while foliar and root application of Leptolyngbya-1267 seems to be more related to the strengthening of the plant through the salicylic acid route. These preliminary results could serve as the basis for a deeper characterization of the biopesticidal and biostimulant effect of both strains, as well as to reveal the benefits derived from the combination of both capacities. [ABSTRACT FROM AUTHOR]

The use of rhizobacteria provide great benefits in terms of nitrogen supply, suppression of plant diseases, or production of vitamins and phytohormones that stimulate the plant growth. At the same time, cyanobacteria can photosynthesize, fix nitrogen, synthesize substances that stimulate rhizogenesis, plant aerial growth, or even suppose an extra supply of carbon usable by heterotrophic bacteria, as well as act as biological control agents, give them an enormous value as plant growth promoters. The present study focused on the in vitro establishment of consortia using heterotrophic bacteria and cyanobacteria and the determination of their effectiveness in the development of tomato seedlings. Microbial collection was composed of 3 cyanobacteria (SAB-M612 and SAB-B866 belonging to Nostocaceae Family) and GS (unidentified cyanobacterium) and two phosphate and potassium solubilizing heterotrophic bacteria (Pseudomonas putida-BIO175 and Pantoea cypripedii-BIO175). The results revealed the influence of the culture medium, incubation time and the microbial components of each consortium in determining their success as biofertilizers. In this work, the most compatible consortia were obtained by combining the SAB-B866 and GS cyanobacteria with either of the two heterotrophic bacteria. Cyanobacteria GS promoted the growth of both rhizobacteria in vitro (increasing logarithmic units when they grew together). While Cyanobacteria SAB-B866 together with both rhizobacteria stimulated the growth of tomato seedlings in planta, leading to greater aerial development of the treated seedlings. Parameters such as fresh weight and stem diameter stood out in the plants treated with the consortia (SAB-B866 and both bacteria) compared to the untreated plants, where the values doubled. However, the increase was more discrete for the parameters stem length and number of leaves. These results suggest that the artificial formulation of microbial consortia can have positive synergistic effects on plant growth, which is of enormous agro-biotechnological interest. [ABSTRACT FROM AUTHOR]

Here we review the suppressive capacity of 14 agroindustrial subproduct-based compost against the disease caused by Xanthomonas campestris pv. vesicatoria (Xcv) in tomato crops. The obtained results have shown that the in vitro compost’s suppressive effect on Xcv growth was mainly due to biotic factors, since sterilised compost samples were not effective. The most effective composts were 44TRI, 50, 51, 52 and 55, while the rest of them apparently did not affect the in vitro growth of the bacterium. When the same composts were applied in a tomato seedbed, the sample named 51 showed the most suppressive effect against the symptoms caused by the pathogen. Disease incidence reduction after this treatment reached 80%. In this case, a clear indirect relationship was detected between disease incidence and fresh weight losses of treated plants. Finally, the suppressive characteristics of an agroindustrial-based compost were improved after the inoculation with a biological control agent, a strain of Bacillus pumilus MSW231 known to be effective against Xcv. In this case, the isolation of the pathogen from infected plants was reduced up to 95% as compared to plants treated with another non-suppressive substrate. The present results indicate that the agroindustrial subproducts-based compost posseses an important suppressive effect towards the disease caused by Xcv, mainly due to biotic factors, and therefore it can be improved by the inoculation with biological control agents, worsened by sterilization and even modified by the inoculation with other biological control agents, so as to obtain an effective compost à la carte. [ABSTRACT FROM AUTHOR]

Some kinds of compost suppress soil-borne plant pathogens and although their exact mode of action is not yet clear, several mechanisms seem to be involved in the supressive effect. The abiotic component of compost is an important factor for its suppressive effect in soils, however it must be kept in mind that compost is considered a source of biocontrol agents against several serious plant pathogens. The main aim of this work was to discriminate the biotic and abiotic components in agroindustrial subproduct-based composts that could be potentially used as suppressive soil amendments. Results have shown that the compost's suppressive effect on mycelial development of Fusarium oxysporum f. sp. melonis (FOM), the causal agent of Fusarium wilt of melon, was due to a combination of biotic and abiotic factors. Similar results were observed when compost extracts were used against the pathogenic fungus. In this case, compost extracts with a concentration between 0.1 and 50% inhibited FOM growth. However, sterilized compost extracts inhibited fungal development when applied at a dose lower than 10%, while higher concentrations (>10%) were not effective, probably due to the toxic substances and nutrient content ratio in the culture media. This can be indicative of a masking of the inhibitory effect at high nutritional levels. Based on these results, we conclude that the suppressive effect of compost is due to a combination of biotic and abiotic factors, though the former are mainly responsible for the biocontrol activity against FOM. [ABSTRACT FROM AUTHOR]

Aims: The aim of this work was to study the effect of high temperatures generated during composting process, on the phytopathogen fungus Fusarium oxysporum f. sp. melonis. This investigation was achieved by both in vivo (semipilot-scale composting of horticultural wastes) and in vitro (lab-scale thermal treatments) assays. Methods and Results: Vegetable residues infected with F. oxysporum f. sp. melonis were included in compost piles. Studies were conducted in several compost windrows subjected to different treatments. Results showed an effective suppression of persistence and infective capacity, as this process caused complete fungal elimination after 2-3 days of composting. In order to confirm the effect of high temperature during this process, in vitro experiments were carried out. Temperature values of 45, 55 and 65°C were tested. All three treatments caused the elimination of fungal persistence. Treatment at 65°C was especially effective, whereas 45°C eliminated fungal persistence only after 10 days. Conclusions: The composting process is an excellent alternative for the management of plant wastes after harvesting, as this procedure is able to suppress infective capacity of several harmful phytopathogens such as F. oxysporum f.sp. melonis. Significance and Impact of the Study: Fusarium oxysporum f.sp. melonis is a plant pathogen fungus specially important in the province of Almería (south-east Spain), where intensive greenhouse horticulture is very extended. High temperatures reached during composting of horticultural plant wastes ensure the elimination of phytopathogen microorganisms such as F. oxysporum f.sp. melonis from vegetable material, providing an adequate hygienic quality in composts obtained. [ABSTRACT FROM AUTHOR]

This study investigated the effects of different aeration intensities on organic matter (OM) degradation, greenhouse gas emissions (GHG) as well as humification during plant residue composting. Three intermittent aeration intensities of 0.084 (Tlow), 0.19 (Tmedium) and 0.34 (Thigh) L min−1kg−1 DM with 30 min on/30 min off were conducted on a lab-scale composting experiment. Results showed that OM mineralization in Thigh was more evident than Tlow and Tmedium, resulting in the highest humic acid content. Humic acid content in Tmedium and Thigh was 15.7% and 18.5% higher than that in Tlow. The average O2 concentration was 4.9%, 9.5% and 13.6% for Tlow, Tmedium and Thigh. Compared with Tmedium and Thigh, Tlow reduced CO2 and N2O emissions by 18.3%–39.6% and 72.4%–63.9%, but the CH4 emission was highest in Tlow. But the total GHG emission was the lowest in Thigh. Linear Discriminant Analysis Effect Size analysis showed that the core bacteria within Tlow mainly belonged to Anaerolineaceae, which was significantly negatively correlated to the emission of CH4. Thermostaphylospora, Unclassified_Vicinamibacteraceae and Sulfurifustis were identified as core bacteria in Tmedium and Thigh, and these genus were significantly postively correlated to CO2 and N2O emissions. Redundancy analysis showed that total orgnic carbon, O2 and electrical conductivity were the key factors affecting the evolution of bacterial community. [ABSTRACT FROM AUTHOR]

The lack of quantitative data regarding the geographical availability of secondary bioresources hinders the exploration of regional valorisation opportunities within the context of circular bioeconomy. The study aimed to identify the main by-products of the food processing and manufacturing industry in eight Northern European countries, including Denmark, Estonia, Finland, Iceland, Latvia, Lithuania, Norway, and Sweden, and propose potential bio-valorisation solutions for these by-products to derive value-added products. By analysing available Food and Agriculture Organization (FAO) statistics for the period between 2015 and 2020 and reviewing the scientific literature, by-product volumes were estimated and respective bio-valorisation methods were summarised in two separate databases. The first database lists the processed food products, their by-products and estimated volumes, while the second details the bio-valorisation methods applicable to these by-products. Estimated by-product volumes provide an understanding of their availability in the Northern European region. Our findings revealed that fresh whey is the predominant by-product in the region, with Denmark generating the highest average volume of 2318.3 kt/year. Similarly, sugar beet pulp, also highest in Denmark, averaged 1421.3 kt/year. Among the bio-valorisation methods studied, whey and brewer's spent grain were the most used substrates, with xylanases, ethanol, and acetic acid being the primary value-added products. This research offers valuable data-driven insights to support the circular bioeconomy in Northern Europe while demonstrating an approach to estimating food industry by-product volumes using commonly reported statistical data. [ABSTRACT FROM AUTHOR]

The lignocellulosic biomass (LCB) is an attractive, sustainable, and environmentally friendly alternative to fossil sources to produce biofuel, biomaterials, and biochemicals. However, its recalcitrant and heterogenous structure challenges its biodegradation and valorization. The gut microbiome of soil invertebrate species has emerged as a rich source of LCB-degrading bacteria and enzymes in terrestrial ecosystems. The primary objective of this investigation was to identify the bacterial communities within the Porcellio dilatatus gut (Crustacea: Isopods), to obtain enriched cultures, and to identify bacterial isolates with LCB-degrading activity. A total of 112 enriched cultures were screened, all exhibiting xylanolytic activity. Among them, 94 displayed cellulolytic activity, 30 showed chitinolytic activity, and 21 demonstrated ligninolytic activity. Four enriched cultures were selected, and 128 bacteria with cellulolytic, xylanolytic, chitinolytic, or ligninolytic activity were isolated and taxonomically classified. The obtained results reinforce the potential of bacterial communities within the digestive tract of soil invertebrates as a valuable source of lignocellulose-degrading microorganisms. Thirty-one isolates underwent in-depth enzymatic characterization, and five were selected and functionally evaluated. An artificial bacterial consortium was constructed to assess the potential benefits of using consortia to achieve enhanced LCB degradation. The positive results of this proof-of-concept artificial consortium (PdG-AC) can be used in future applications and is a valuable tool for enzymatic and microbial consortia engineering by, e.g., changing growth conditions for enhanced LCB-degrading abilities. Key points: • The gut microbiome of Porcellio dilatatus was characterized. • Porcellio dilatatus gut hosts many lignocellulose-degrading bacteria. • Developed an artificial bacterial consortium for lignocellulose degradation. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) produced by potential plant growth-promoting rhizobacteria (PGPR) play an important role in plant interactions. However, the mechanisms underlying this phenomenon are not well understood. Our findings show that the influence of VOCs from the PGPR strain Bacillus vallismortis (EXTN-1) on tobacco plant growth is dependent on the culture media used. The VOCs released from sugar-rich media such as potato dextrose agar (PDA) and King's B (KB) media were highly effective. However, exposure to VOCs from nutrient agar (NA), tryptic soy agar (TSA), and Luria-Bertani (LB) resulted in chlorosis and stunted plant growth. This effect was caused by the discharge of a large amount of ammonia that altered the pH of the plant growth media. Seedlings exposed to VOCs for 10 days exhibited improved growth even after the VOCs were eliminated under greenhouse conditions. Priming of seeds with VOCs for 24 and 48 h induced higher growth than the untreated control, and seeds with 48 h exposure were better as compared to 24 h treatment. Chemical characterization of VOCs emitted by EXTN-1 in different media using solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS) showed the presence of 2,3-butanedione and monoxime in all spectra. However, 1-butanol was the prominent peak in VOC of EXTN-1 grown in KB and NA, while acetoin was highest in PDA, followed by KB. Heneicosane and benzaldehyde were exclusively produced in NA media, and these synthetic compounds improved growth in the I-plate assay. This work indicates that VOCs released from EXTN-1 are important for the growth-promoting effect of EXTN-1. [ABSTRACT FROM AUTHOR]

Composting is an environmentally friendly method for transforming the nutrients present in livestock manure into organic fertilizer. In this study, the compost quality-enhancing and N2O and CH4 emissions-reducing effects of superphosphate were investigated during industrial-scale in-vessel composting of swine manure. Alongside a control group, three different doses of superphosphate were tested: 5% (SSP5), 10% (SSP10), and 15% (SSP15). The results revealed that the superphosphate reduced the N2O and CH4 emissions by 18.5–26.3% and 15.8–25.1%, respectively. In addition, the superphosphate enhanced both the N and P contents of the compost. However, it had an adverse impact on compost maturity, with the SSP15 dose showing the lowest germination index (GI) at 70.4% and the highest electrical conductivity (EC) at 9.04 mS·cm−1. These findings suggest that superphosphate has potential for greenhouse gas mitigation and nutrient augmentation in industrial composting. Although the economic benefits of superphosphate addition for GHG reduction are limited, the technology holds considerable economic potential for nitrogen conservation. Further investigations should focus on combining superphosphate addition with other improvements, considering both compost quality and economic viability. [ABSTRACT FROM AUTHOR]

Background: Before the COVID-19 outbreak, food microbiology was essential in identifying and preventing foodborne pathogens like Salmonella and E. coli. The pandemic underscored the importance of this discipline, highlighting the need for enhanced surveillance and microbiological control in the food chain to avert future public health threats. This research aimed to advance knowledge management in bioeconomy, focusing on eco-intensification and biotechnology applications that directly impact food microbiology during the COVID-19 crisis. Methodology: The study conducted a comprehensive literature review grounded in the epistemological principles of bioeconomy, utilizing the Bibliometric Scopus database. This approach explored the development of eco-intensification and biotechnology applications within food safety and nutrition microbiology. Results: Findings reveal a significant disconnect between research efforts in bioeconomy and food microbiology, emphasizing the need for enhanced interdisciplinary collaboration to address food security and sustainable production challenges. The study advocates for integrating microbiological insights within bioeconomic frameworks to improve food safety and sustainability. The COVID-19 pandemic also exposed vulnerabilities in the food supply chain, leading to shifts in consumer behavior, including increased online food orders and a greater emphasis on hygiene practices and local products, thus highlighting the necessity for more resilient food systems. Conclusion: The study concludes that the pandemic has reshaped food production practices, stressing the integration of food microbiology within bioeconomic frameworks. It identifies a gap in interdisciplinary research and suggests recommendations for decision-makers to strengthen public health agendas and foster resilience through eco-intensification and biotechnology applications. [ABSTRACT FROM AUTHOR]

The biomass of native microorganisms in food waste (FW) suitable for accelerated composting is initially low and requires time for adaptation. Adding of efficient hydrolytic microorganisms should be able to enhance compost-specific microbial activity, adjust microbial community structure, and potentially hasten FW biodegradation. This study aimed to identify bacterial and fungal strains with growth characteristics suitable for accelerating FW composting. Over 7 weeks, FW was composted in a pilot-scale test, either inoculated at the start or on day 28 with three different mixtures of 10 autochthonous Bacillus and Penicillium spp. strains known for their high hydrolytic activity. The effects of inoculation were assessed by measuring the rate of carbon dioxide (CO2) and ammonia (NH3) production and also the increase in temperature due to spontaneous exothermic activity of the enhanced microbial population degrading FW. Inoculation with Bacillus spp., particularly B. amyloliquefaciens and B. subtilis , at the beginning of composting increased CO2 production nearly 3-fold while maintaining stable ammonia production and temperature. The high concentration of Bacillus relative to native FW microorganisms led to dominant fermentation processes even in the presence of oxygen, resulting in moderate heat release and elevated production of volatile organic compounds. Introducing Penicillium spp. at a later stage (day 28) increased CO2 production nearly 2-fold, along with higher NH3 levels and temperature. These findings highlight the significance of inoculation timing and microbial composition in regulating metabolic pathways during FW composting degradation, offering insights for designing effective microbial formulations for composting. [ABSTRACT FROM AUTHOR]

The biomass of native microorganisms in food waste (FW) suitable for accelerated composting is initially low and requires time for adaptation. Adding of efficient hydrolytic microorganisms should be able to enhance compost-specific microbial activity, adjust microbial community structure, and potentially hasten FW biodegradation. This study aimed to identify bacterial and fungal strains with growth characteristics suitable for accelerating FW composting. Over 7 weeks, FW was composted in a pilot-scale test, either inoculated at the start or on day 28 with three different mixtures of 10 autochthonous Bacillus and Penicillium spp. strains known for their high hydrolytic activity. The effects of inoculation were assessed by measuring the rate of carbon dioxide (CO2) and ammonia (NH3) production and also the increase in temperature due to spontaneous exothermic activity of the enhanced microbial population degrading FW. Inoculation with Bacillus spp., particularly B. amyloliquefaciens and B. subtilis , at the beginning of composting increased CO2 production nearly 3-fold while maintaining stable ammonia production and temperature. The high concentration of Bacillus relative to native FW microorganisms led to dominant fermentation processes even in the presence of oxygen, resulting in moderate heat release and elevated production of volatile organic compounds. Introducing Penicillium spp. at a later stage (day 28) increased CO2 production nearly 2-fold, along with higher NH3 levels and temperature. These findings highlight the significance of inoculation timing and microbial composition in regulating metabolic pathways during FW composting degradation, offering insights for designing effective microbial formulations for composting. [ABSTRACT FROM AUTHOR]

Plastic waste pollution has become a global crisis, with millions of tons of plastic expected to accumulate in landfills and in natural environments, posing a serious threat to wildlife and human health. As current recycling methods remain inefficient, there is an urgent need for innovative enzymatic solutions to break down plastics and enable a circular economy approach. In this study, we explore the plastic-degrading potential of microorganisms enriched from activated sludge (AS) sourced from a municipal wastewater treatment plant (WWTP)—a known microplastic-contaminated industrial niche. Five microbial consortia (i.e., microbiomes) were enriched under selective pressure using low-carbon conditions and high concentrations of polyester polymers, including post-consumer PET, post-consumer PLA, and virgin PLA. Enrichment was performed for 100 days at 37 °C and 50 °C, followed by microbiomes isolation and metagenomic analysis to identify plastic-active bacteria and their enzymes. The results revealed that PLA polymers, but not post-consumer PET, were effectively degraded by the microbiomes, as confirmed by nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC), showing significant molecular weight reduction compared to the abiotic controls. Microbial community analysis highlighted a distinct enrichment profile driven by the polymer composition and the temperature. At 50 °C, the Bacillales order became the predominant population, whereas at 37 °C, a more diverse community within the Proteobacteria and Actinobacteria phyla were selected. Nonetheless, the enriched microbial communities at both temperatures included phyla with members known for polyester degradation. Moreover, at 50 °C, enrichment of putative PET/PLA hydrolases was also observed. These findings suggest that AS microorganisms are a reservoir of polyester-active enzymes, particularly PLA-depolymerases, and hold promise for advancing biotechnological strategies to mitigate plastic pollution through re- and up-cycling. [ABSTRACT FROM AUTHOR]

Copyright of Waste & Biomass Valorization is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Kiwi waste from the calibration process is a major environmental problem of kiwi production due to landfill deposition. This work aims to contribute to the agronomic use of recycled kiwi waste through composting. With this objective, a composting experiment was carried out with kiwi fruit waste mixed with 5%, 10% and 20% (fresh weight) of wheat straw from bundles used to protect kiwifruit trunks from frost, as abulking agent to increase aeration, in the piles 5S, 10S and 20S, respectively. The highest temperatures for piles 5S and 10S were above 60°C, whereas the temperature did not reach 40°C in the pile with the highest straw content (20S) because the aeration increased heat loss in addition to increased C/N ratio of this pile. Also, the amount of organic matter mineralized decreased with increasing amount of straw because of the high C/N ratio of the straw. The highest total N (29.7 g kg−1) and the lowest C/N ratio (13) of the compost with 5% of straw is important from the agricultural point of view to promote N availability. In contrast, the high electrical conductivity (4.6 dS m−1) of this compost increases the risk of salt accumulation in the soil. Our results show that the compost with 10% straw, with high degree of maturation, absence of poor hygiene indicators as coliforms and pathogens as Salmonella sp., high organic matter content and rich in nutrients, together with the adequate compost pH and low electrical conductivity improves compost quality. [ABSTRACT FROM AUTHOR]

Introduction: Tunnel composting technology for preparing Agaricus subrufescens cultivation media can achieve a higher biological efficiency (BE) and a lower contamination rate (CR). However, this technology lacks in-depth and systematic study. Methods: In the present study, the changes in the microbiome and microbial metabolic functions were surveyed using metagenomic analysis. The physicochemical parameters, agronomic properties and nutritional qualities were also evaluated. Results and discussion: Results showed that the contents of cellulose, hemicellulose and lignin dropped to 10.18, 11.58, 27.53%, respectively at the end of composting. The tunnel composting technology led to significant increases in crude protein content (32.56%) and crude fiber content (13.68%). Variations of physicochemical characteristics led to different successions of microbial communities. Bacteria manifested significantly higher abundance than fungi. Firmicutes, Actinobacteriota, Chloroffexi and Deinococcota were the predominant bacterial phyla. Ascomycota and Basidiomycota were the dominant fungal phyla in the thermophilic phase. Pseudonocardia , Truepera , and Thermopolyspora were positively correlated with the yield of A. subrufescens. In addition to TN, most of the physicochemical properties were significantly correlated with fungal communities in the thermophilic phase. The metabolisms of carbohydrate, amino acid and energy were the primary enrichment pathways. These findings deepen the understanding of microbial communities composition during the composting of A. subrufescens substrates. Moreover, this study provides a basis for improving tunnel composting technology. [ABSTRACT FROM AUTHOR]

Three different enzymes alkaline phosphatase, Urease and Dehydrogenase were measured during this study to monitor the organic matter dynamics during semi-industrial composting of mixture A with 1/3 sludge+2/3 palm waste and mixture B with ½ sludge+1/2 palm waste. The phosphatase activity was higher for Mix-A (398.7 µg PNP g−1 h−1) than Mix-B (265.3 µg PNP g−1 h−1), while Mix-B (103.3 µg TPF g−1d−1) exhibited greater dehydrogenase content than Mix-A (72.3 µg TPF g−1 d−1). That could contribute to the dynamic change of microbial activity together with high amounts of carbonaceous substrates incorporated with the lignocellulosic. The gradual increase in the dehydrogenase from the compost Mix-A implies that high lignocellulosic substrate requires gradual buildup of dehydrogenase activity to turn the waste into mature compost. A higher pick of urease with a maximum activity of 151.5 and 122.4 µg NH4-N g−1 h−1 were reported, respectively for Mix-A and B. Temperature and pH could also influence the expression of enzyme activity during composting. The machine learning well predicted the compost quality based on NH3/NO3, C/N ratio, decomposition rate and, humification index (HI). The root mean square error (RMSE) values were 1.98, 1.95, 4.61%, and 4.1 for NH+3/NO−3, C/N ratio, decomposition rate, and HI, respectively. The coefficient of determination between observed and predicted values were 0.87, 0.93, 0.89, and 0.94, for the r NH3/NO3, C/N ratio, decomposition rate, and HI. Urease activity significantly predicted the C/N ratio and HI only. The profile of enzymatic activity is tightly linked to the physico-chemical properties, proportion of lignocellulosic-composted substrates. Enzymatic activity assessment provides a simple and rapid measurement of the biological activity adding understunding of organic matter transformation during sludge-lignocellulosic composting. [ABSTRACT FROM AUTHOR]

Introduction: Organic wastes are composted to increase their plant nutritional value, but little is known about how this might alter the bacterial and archaeal community structure and their genes. Methods: Cow manure was collected from three local small-scale farmers and composted under controlled conditions, while the bacterial and archaeal communities were determined using shotgun metagenomics at the onset and after 74 days of composting. Results: The bacterial, archaeal, methanogen, methanotrophs, methylotroph, and nitrifying community structures and their genes were affected by composting for 74 days, but the original composition of these communities determined the changes. Most of these archaeal and bacterial groups showed considerable variation after composting and between the cow manures. However, the differences in the relative abundance of their genes were much smaller compared to those of the archaeal or bacterial groups. Discussion: It was found that composting of different cow manures did not result in similar bacterial or archaeal communities, and the changes that were found after 74 days were defined by the original populations. However, more research is necessary to determine if other composting conditions will give the same results. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) and greenhouse gas (GHG) emissions are substantial contributors to C and N loss in composting. Lignite can increase N retention by absorbing ${\rm N}{\rm H}_4^ +$ N H 4 + and NH3. However, the effects of co-composting on NH3 and GHG emissions in view of closing nutrient cycle are still poorly investigated. In the study, poultry litter was composted without (CK) or with lignite (T1) or dewatered lignite (T2), and their respective composts ${\rm N}{\rm H}_4^ +$ N H 4 + Com_CK, Com_T1, and Com_T2) were tested in a soil incubation to assess NH3 and GHG emission during composting and following soil utilization. The cumulative NH3 flux in T1 and T2 were reduced by 39.3% and 50.2%, while N2O emissions were increased by 7.5 and 15.6 times, relative to CK. The total GHG emission in T2 was reduced by 16.8% compared to CK. Lignite addition significantly increased nitrification and denitrification as evidenced by the increased abundances of amoA, amoB, nirK, and nirS. The increased reduction on NH3 emission by dewatered lignite could be attributed to reduced pH and enhanced cation exchangeable capacity than lignite. The increased N2O was related to enhanced nitrification and denitrification. In the soil incubation experiment, compost addition reduced NH3 emission by 72%∼83% while increased emissions of CO2 and N2O by 306%∼740% and 208%∼454%, compared with urea. Com_T2 strongly reduced NH3 and GHG emissions after soil amendment compared to Com_CK. Overall, dewatered lignite, as an effective additive, exhibits great potential to simultaneously mitigate NH3 and GHG secondary pollution during composting and subsequent utilization of manure composts. [ABSTRACT FROM AUTHOR]

Anaerobic digestion's contribution to sustainable development is well established. It is a sustainable production process that enables energy to be saved and produced and efficient pollution control processes to be implemented, thereby contributing to the sustainable development of our societies. Optimizing biogas yields from the anaerobic digestion of municipal organic waste is crucial for maximum energy recovery and has become an important topic of interest. Substrate particle size is a key process parameter in biogas production and precedes other pretreatment methods for most organic materials. This study aims to evaluate the impact of particle size and incubation period on biomethane production from municipal solid waste. Sampling of municipal solid waste was carried out in waste pre-collection in the city of Ouagadougou, Burkina Faso. Waste characterization showed lignocellulolytic green waste (grass, dead leaves), waste composed of fruit and leafy vegetables and leftover food waste. TableCurve 3D v4.0 software was used to develop an optimal mathematical model to correlate particle size and biomethane productivity to describe optimal production parameters. Particle sizes ranging from 2000 to 63 µm high biogas production values, specifically 385.33 and 201.25 L·kg−1 of MSV. PCA analysis clearly showed a high correlation between particle size and biogas production, with optimum production recorded for size 250 µm with a biomethane production value of 187.53 L·kg−1 of MSV. The average relative errors and RMSE for CH4 content were improved by 24.31% and 44.97%, respectively. The data calculated with the developed mathematical model and the existing experimental data were compared and permutated to validate the model. This work enabled the identification of a mathematical model that describes the correlations between the input parameters of an experiment and the monitored parameters, as well as the definition of the particle size that allows for the optimal production of biomethane. [ABSTRACT FROM AUTHOR]

Agricultural soil has great potential to address climate change issues, particularly the rise in atmospheric CO2 levels. It offers effective remedies, such as increasing soil carbon content while lowering atmospheric carbon levels. The growing interest in inoculating soil with live microorganisms aims to enhance agricultural land carbon storage and sequestration capacity, modify degraded soil ecosystems, and sustain yields with fewer synthetic inputs. Agriculture has the potential to use soil microalgae as inoculants. However, the significance of these microorganisms in soil carbon sequestration and soil carbon stabilization under field conditions has yet to be fully understood. Large-scale commercial agriculture has focused on the development and use of inoculation products that promote plant growth, with a particular emphasis on enhancing yield attributes. Gaining more profound insights into soil microalgae's role in soil carbon cycling is necessary to develop products that effectively support soil carbon sequestration and retention. This review comprehensively explores the direct and indirect mechanisms through which soil microalgae contribute to soil carbon sequestration, highlighting their potential as microbial inoculants in agricultural settings. This study underlines the need for more research to be conducted on microalgae inoculation into agricultural soil systems aimed at mitigating carbon emissions in the near future. [ABSTRACT FROM AUTHOR]

Soil carbon mineralization plays an important role in the carbon cycle of terrestrial ecosystems. When it comes to the soil carbon cycle, however, research on how carbon mineralization characteristics of fertilized Camellia oleifera forest soil respond to temperature changes remains limited. This study used an indoor constant temperature incubation method to examine the effects of the vermicomposting of cow dung by applying it at three different quantities (A: 0.8 kg earthworm + 62.5 kg cow dung/Camellia oleifera; B: 1.6 kg earthworm + 125 kg cow dung/Camellia oleifera; C: 2.4 kg earthworm + 187.5 kg cow dung/Camellia oleifera) and set a control group with Camellia oleifera forest not being fertilized (CK). This research was conducted with incubators set at 5 °C, 15 °C, 25 °C, and 35 °C, and with continuous monitoring of soil carbon mineralization characteristics and temperature sensitivity of organic carbon mineralization. The results showed significant increases in soil MBC, MBN, DOC, DON, NO3−-N, and NH4+-N in groups with applications of cow-dung vermicomposting compared to CK. Except at 35 °C, soil respiration in the Camellia oleifera of Group A was consistently the strongest. The maximum soil carbon emission (C0) was determined through a simulation of potential carbon emissions, with all correlation coefficients exceeding 0.95. The contents of TC and TN were positively correlated with MBC and MBN (p <0.001), while the C: Nmicro was negatively correlated with TN, AN, MBN, and inorganic nitrogen. Based on temperature sensitivity (Q10), the influence of temperature on soil mineralization rate was observed. The vermicomposting of cow dung had a noticeable effect, as Group B showed significantly stronger enzyme activity compared to other groups. These results indicate that changes in MBC can impact the stability of soil carbon mineralization. The roles of soil moisture and microorganisms should be considered when predicting dynamic changes in the soil carbon pool of Camellia oleifera when applying fertilizers and improving its soil carbon sequestration capacity. [ABSTRACT FROM AUTHOR]

Copyright of Environmental & Social Management Journal / Revista de Gestão Social e Ambiental is the property of Environmental & Social Management Journal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

While organic fertilizers enhance tobacco quality and economic value, their low maturity levels often limit their effectiveness when applied within the same growing season, discouraging farmer adoption. Conventional composting methods typically require over 90 days to achieve full maturity. This study aimed to optimize composting methods and material formulations for large-scale factory production to shorten the fermentation period, enabling same-season application and benefits. Two large-scale experiments (each exceeding 100 tons) compared molecular membrane forced aeration combined with static and windrow composting against traditional windrow composting. Different material ratios of cow dung, mushroom residue, and distillery waste were also evaluated. Results showed that the optimized method, utilizing molecular membrane technology and adjusted material ratios, reduced the composting time from over 90 days to 60 days. The optimal formula consisted of cow dung, mushroom residue, and distillery waste at a 4:3:3 dry weight ratio with a moisture content = 63%. After 60 days, this optimized process yielded organic fertilizer meeting all quality standards, including humic acid content, nutrient levels, and absence of harmful organisms. This accelerated composting method facilitates same-season fertilizer application, benefiting farmers and enhancing the efficiency and cost-effectiveness of organic fertilizer production. [ABSTRACT FROM AUTHOR]

In this editorial, we discuss the need for a new, long-term strategy for managing human excrement (feces and urine) to facilitate health equity and promote environmental sustainability. Human excrement composting (HEC), a human-directed process driven by highly variable and diverse microbiomes, provides a means to advance this need and we discuss how microbiome science can help to advance HEC research. We argue that the technological advancements that have driven the growth of microbiome science, including microbiome and untargeted metabolome profiling, can be leveraged to enhance our understanding of safe and efficient HEC. We conclude by presenting our perspective on how we can begin applying these technologies to develop accessible procedures for safe HEC. [ABSTRACT FROM AUTHOR]

Background Burkholderia: is a phosphorus solubilizing microorganism discovered in recent years, which can dissolve insoluble phosphorus compounds into soluble phosphorus. To investigate the effects of Burkholderia and calcium phosphate on the composting of Torreya grandis branches and leaves, as well as to explain the nutritional and metabolic markers related to the composting process. Methods: In this study, we employed amplicon sequencing and untargeted metabolomics analysis to examine the interplay among phosphorus (P) components, microbial communities, and metabolites during T. grandis branch and leaf waste composting that underwent treatment with calcium phosphate and phosphate-solubilizing bacteria (Burkholderia). There were four composting treatments, 10% calcium phosphate (CaP) or 5 ml/kg (1 × 108/ml Burkholderia) microbial inoculum (WJP) or both (CaP + WJP), and the control group (CK). Results: The results indicated that Burkholderia inoculation and calcium phosphate treatment affected the phosphorus composition, pH, EC, and nitrogen content. Furthermore, these treatments significantly affected the diversity and structure of bacterial and fungal communities, altering microbial and metabolite interactions. The differential metabolites associated with lipids and organic acids and derivatives treated with calcium phosphate treatment are twice as high as those treated with Burkholderia in both 21d and 42d. The results suggest that calcium phosphate treatment alters the formation of some biological macromolecules. Conclusion: Both Burkholderia inoculation and calcium phosphate treatment affected the phosphorus composition, nitrogen content and metabolites of T. grandis branch and leaf waste compost.These results extend our comprehension of the coupling of matter transformation and community succession in composting with the addition of calcium phosphate and phosphate-solubilizing bacteria. [ABSTRACT FROM AUTHOR]

Huge quantities of municipal solid waste and food chain supply waste are unfavourable outcomes of rapid population growth and urbanization. Organic municipal waste majorly consists of decomposable, recyclable, and inert waste and contributes to 57% of municipal waste generated globally. Fruits and vegetables wastes are major component of organic municipal waste, and contains significant amount of carbohydrates, proteins, fats, minerals and fibres that can be valorised through various innovative and sustainable strategies. One of the most important approaches is leveraging the catalytic capabilities of microbial enzymes to convert complex organic compounds to varied valuable products like, essential oils, bio-oil, ethanol, biogas, phenolics, flavonoids, anthocyanin, dietary products etc. Development of environment friendly sustainable processes also handles the challenges associated with waste disposal and boost nation's financial status through circular bioeconomy. The present review focusses on details of major organic municipal waste, with specific emphasis on fruit and vegetable remains, their composition, management and value-added products obtained from these resources. It also gives a detailed account on green technology approach of waste valorisation through microbial enzymes, recent technological interventions involved in the process and discusses the future market potential and growth prospects in the studied area. [ABSTRACT FROM AUTHOR]

Introduction: Humus can be formed during composting through biological pathways, nonetheless, the mechanisms through which bacterial and fungal communities govern the development of humus in compost with the addition of biochar remain uncertain. Methods: In this study, compost with cow dung and maize stover as feedstock was employed as a control group, and compost with 10% biochar added on top of the feedstock was adopted as a treatment group to investigate the effect of bacterial and fungal communities on humus formation during biochar composting. Results and Discussion: The results demonstrated that the humic acid content increased by 24.82 and 25.10% at the cooling and maturation stages, respectively, after adding biochar. Besides, the degree of polymerization content in the maturation stage was elevated by 90.98%, which accelerated the humification process of the compost. During the thermophilic and maturity stages, there was a respective increase of 51.34 and 31.40% in reducing sugar content, suggesting that the inclusion of biochar could furnish ample reducing sugar substrate for the Maillard reaction. The addition of biochar reduced the number of humus precursorassociated genera by 35, increased the number of genera involved in humus synthesis by two, and enhanced the stability of the cross-domain network between bacteria and fungi, which confirms that microorganisms contribute to the humification process by decreasing humus precursor consumption as well as increasing humus synthesis with the addition of biochar. Additionally, adding biochar could enhance the humification capacity of the compost pile by dominating the Maillard reaction with reducing sugars as the substrate and strengthening the function of humus synthesis-associated genera. This study enhances our comprehension of the regulatory pathways of biochar in the humification process during composting. [ABSTRACT FROM AUTHOR]

Pesticide use in crops is a severe problem in some countries. Each country has its legislation for use, but they differ in the degree of tolerance for these broadly toxic products. Several synthetic pesticides can cause air, soil, and water pollution, contaminating the human food chain and other living beings. In addition, some of them can accumulate in the environment for an indeterminate amount of time. The agriculture sector must guarantee healthy food with sustainable production using environmentally friendly methods. In this context, biological biopesticides from microbes and plants are a growing green solution for this segment. Several pests attack crops worldwide, including weeds, insects, nematodes, and microorganisms such as fungi, bacteria, and viruses, causing diseases and economic losses. The use of bioproducts from microorganisms, such as microbial biopesticides (MBPs) or microorganisms alone, is a practice and is growing due to the intense research in the world. Mainly, bacteria, fungi, and baculoviruses have been used as sources of biomolecules and secondary metabolites for biopesticide use. Different methods, such as direct soil application, spraying techniques with microorganisms, endotherapy, and seed treatment, are used. Adjuvants like surfactants, protective agents, and carriers improve the system in different formulations. In addition, microorganisms are a tool for the bioremediation of pesticides in the environment. This review summarizes these topics, focusing on the biopesticides of microbial origin. [ABSTRACT FROM AUTHOR]

The main objective of this study was to evaluate the potential of olive mill wastewater (OMW) as an organic fertilizer through co-composting with various agricultural by-products. OMW was mixed with agricultural by-products, including maize silage, sugar beet pulp, and sugarcane bagasse, in controlled proportions and conditions. The study was conducted at the National Institute of Agricultural Research in Rabat, Morocco. The composting process was monitored over time, focusing on the evolution of key physicochemical parameters and phenol content of each mixture. The results showed that the performance of the composts varied, with the mixture containing sugar beet pulp (SBPO) exhibiting the most promising results, followed by maize silage (MSO) and sugarcane bagasse (SBO). These results suggest that co-composting OMW with agricultural by-products can produce high-quality organic fertilizers, thus reducing the need for inorganic alternatives and providing a sustainable waste management solution in the olive oil industry. It highlights the potential for reducing phenols characteristic of OMW and promoting sustainable agricultural practices. The application of the composts to crops was not tested, highlighting the need for further research in this regard. Future investigations should focus on evaluating the long-term effects of OMW-derived composts on soil health and crop productivity. This study explored a combination of materials that, to the authors’ knowledge, has not been previously documented in scientific literature. The results underscore the importance of sustainable waste management practices and their potential role in improving soil fertility and reducing the environmental impact associated with olive oil production. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sustainable alternatives are essential to improving agriculture production to meet the growing world's critical demands. Cyanobacteria and microalgae are considered renewable resources with a wide range of potential uses in the agricultural sector. We aimed to isolate cyanobacteria and microalgae from the mud of a carbon dioxide-rich sulfur pond and to investigate their plant growth-promoting (PGP) and soil bio-consolidating ability. Mud samples were subjected to DNA extraction and 16S rRNA gene sequencing to characterize the prokaryotic community. Phototrophic culturable microbiota was isolated and evaluated for different PGP properties. The most relevant isolates were combined in a consortium and used for in vitro bioconsolidation activity. In a greenhouse experiment, the isolates were evaluated for their ability to promote salinity stress tolerance in sunflower plants. Metabarcoding results showed that most Amplicon Sequence Variants (ASV) were associated with Actinobacteriota (35%), Proteobacteria (19%), and Acidobacteriota (11%) at the phylum level and Unknown (32%) and uncultured (31%) lineages at the genus level. The culture-dependent method yielded eight isolates associated with cyanobacteria and microalgae genera. The isolates obtained showed interesting PGP activities. Isolates C1, C2, and M1 were selected based on phosphate solubilization (85.6 µg PO43- mL-1 on average), indoles (C1 and M1 0.54 µg mL-1 IAA equivalents on average), and ACC deaminase activity (C2 and M1 6.00 µmol α-KB mg proteins-1 h-1). The consortium efficiently consolidated sand particles in the presence of calcium carbonate by forming activities biomineralized aggregates. In planta results showed positive effects of the consortium on Helianthus annuus L., plant growth under normal conditions and salt stress. The positive effects on soil and plants indicated their effectiveness as bioconsolidants and biostimulant agents. Our findings highlight the interesting potential of cyanobacteria and microalgae applications in sustainable agriculture. [ABSTRACT FROM AUTHOR]

Aerobic composting is an effective way to recycle solid waste. Composting promotes the transformation of degradable organic matter in solid waste into mature manure, precursors of humic substances, by microorganisms widely existed in nature, so as to provide nutrient rich fertilizer for the growth of crops. The community and function of microorganisms play a key role in the successful progress of composting. In recent years, with the vigorous development of molecular biology technology, the succession of microbial community in each stage of composting process has been studied more deeply. Thus, we have a deeper understanding of the metabolic function and functional groups of microorganisms in the composting process. The succession law of microbial community in different stages of composting can be summarized as follows: from mesophilic bacteria and fungi to cellulose decomposing bacteria, then cellulose decomposing bacteria, finally lignin decomposing bacteria. These studies will help us develop microbial additives and improve the efficiency of composting. This paper systematically summarizes the research progress of these molecular biology technologies applied in studies on the microbial community of composting, summarizes the research results of succession changes of microbial community in all stages of composting in recent years, introduces the application of microbial additives in aerobic composting, and prospects the future development of microbial additives. [ABSTRACT FROM AUTHOR]

The increasing generation of biodegradable solid waste has generated significant interest in decentralized in-vessel composting as an alternative to centralized systems. An optimized waste decomposer microbial formulation, comprising Bacillus cereus C1 and Aspergillus niger P-19 selected for their ability to produce multiple carbohydrases, was prepared using a low-cost medium. The capsular preparation of the waste decomposer microbial formulation was inoculated into a sophisticated decentralized in-vessel composter that had already been fed with 40 kg of biodegradable composite kitchen waste. The waste decomposer formulation effectively stabilized the organic materials by releasing a significant amount of enzymes, while the composter provided an optimal environment for rapid composting. The process lasted for 16 days and resulted in the production of high-quality stabilized compost that improved the growth yield of Brassica juncea (mustard), Spinacia oleracea (spinach), and Raphanus sativus (radish). The decentralized mode of management incurred an operational expense of US $0.02 (INR 1.87) per kilogram, effectively eliminating the requirements for labor, transportation, and waste segregation expenses. [ABSTRACT FROM AUTHOR]

The massive yield of brewers' spent grain (BSG) waste inevitably threaten environmental health. Here, solid-state fermentation (SSF) technology featuring multi-strain (MS) inoculation and high-throughput sequencing technology were employed to facilitate the sustainable and clean recycling of BSG waste while revealing the associated underlying microbiological and metabolic mechanisms. MS inoculation displayed a lower pH value (3.91 vs. 4.12) and neutral detergent fiber content (446.24 vs. 476.23 g/kg DM), a higher levels of lactic acid (86.64 vs. 33.07 g/kg DM), acetic acid (6.13 vs. 4.87 g/kg DM), propionic acid (2.78 vs. 2.18 g/kg DM) and crude protein (307.5 vs. 289.15 g/kg DM) than those in the control group. Moreover, MS inoculation inhibited the formation of nonprotein- N and ammonia-N, and spoilage microorganism resuscitation, while enhanced substrate preservation. Microbiologically, during the SSF, the group treated with MS inoculation exhibited an increase in the relative abundance of Leuconostoc (0.58%-6.60%), Weissella (6.22%-15.42%), Enterococcus (3.15%-9.08%), Bacillus (17.63%-31.29%), Lactobacillus (12.89%-8.29%), Pseudoalteromonas (12.87%-16.29%), and a decrease in the relative abundance of Acinetobacter (0.79%-0.02%) and Enterobacteriaceae (0.78%-0.24%). Metabolically, starch and sucrose metabolism, arginine and proline metabolism, and phenylalanine metabolism significantly influenced the quality of extruded BSG fermented by MS during SSF. The examination of the correlation between the microbiota, metabolites, and fermentation parameters revealed that complex interactions between microbes and the environment factors impact metabolite production. Collectively, inoculating with MS improved fermentation quality and stability, facilitated the clean recycling of BSG, which is linked to complex interactions among microbes, the environment factors and metabolite production. [ABSTRACT FROM AUTHOR]

In this editorial, we discuss the need for a new, long-term strategy for managing human excrement (feces and urine) to facilitate health equity and promote environmental sustainability. Human excrement composting (HEC), a human-directed process driven by highly variable and diverse microbiomes, provides a means to advance this need and we discuss how microbiome science can help to advance HEC research. We argue that the technological advancements that have driven the growth of microbiome science, including microbiome and untargeted metabolome profiling, can be leveraged to enhance our understanding of safe and efficient HEC. We conclude by presenting our perspective on how we can begin applying these technologies to develop accessible procedures for safe HEC. 7pGsS1zupHQArt6oeLLwtF Video Abstract [ABSTRACT FROM AUTHOR]

As organic waste is converted to usable amendments via composting, there are large CO2 emissions associated with the decomposition of organic matter via microorganisms. While the active composting phase produces the largest emissions over a short duration, compost can often be stored during and after the maturation phase for much longer periods of time, increasing cumulative emissions. As such, the objectives of this study were to examine the spatial and temporal variability associated with in situ emissions sampling while identifying the environmental and chemical controls on emissions in windrow composting facilities during and after the maturation phase. A total of 665 flux measurements were taken from four windrows representing different ages and compositions between June and November 2020. Factorial analysis of covariance (ANOVA) was used to determine the variability between sampling locations, while multiple linear regression was used to identify those parameters which had the most influence on CO2 flux. Emissions showed significant variability over time that were attributed to ambient temperatures. During the summer, each windrow reached peak emissions between 5.0 and 32.3 g CO2 m-2 hr-1. As temperatures cooled, the windrows saw a 62%-86% decline in emissions, generally falling below 2 g CO2 m-2 hr-1. Significant differences occurred between the top-most sampling location and all others on the windrow, emitting between 33%-100% more CO2. The environmental controls of surface temperature, moisture content, and internal temperature showed the highest influence on emissions (R2 = 0.62). Chemical properties including organic nitrogen, carbon, pH, magnesium, and nitrate also showed significant influence (R2 = 0.43). This research has shown that environmental factors including temperature and moisture show the strongest influence over emission rates in mature compost. A significant negative effect of organic nitrogen on CO2 flux was found, indicating that increased presence of organic nitrogen would aid in the retention of carbon after the maturation phase, acting to lower total emissions. [ABSTRACT FROM AUTHOR]

Nitrogen-fixing cyanobacterial consortia are an alternative to the indiscriminate use of chemical fertilizers that affect the environment, fix atmospheric nitrogen, and can therefore be used as plant growth promoters, synthesize various substances such as auxins, vitamins, and total proteins, and fix atmospheric biofertilizers and soil conditioners. The present study aimed to obtain and develop, by biotechnological means, two consortia of cyanobacteria isolated from the root and rhizosphere of Carica papaya grown in sandy loam soil. The culture was carried out in Blue Green Medium without modified nitrogen (BG110), with aeration of 0.32 L min−1, at a light intensity of 48.83 μEm−2s−1, and a temperature of 22 ± 2 °C. Two consortia consisting of Nostoc commune, Aphanothece minutissima, Planktothrix sp. (C1), Nostoc commune, Calothrix sp., and Aphanothece minutissima (C2) were isolated and morphologically identified. The effective development of these consortia was verified at the laboratory level by obtaining biomass in dry weight as well as photosynthetic pigments, proteins, carbohydrates, and lipids. Germination parameters were determined in seeds of Cucumis sativus L. var. Market plus treated with the nitrogen-fixing cyanobacteria consortia, obtaining a higher germination percentage (>90%), greater root length (>6 cm), and higher vigour index I (513), II (13.02) for the C2 consortium. This broadens the spectrum of rhizosphere-derived microorganisms with potential as growth biostimulators. [ABSTRACT FROM AUTHOR]

Simple Summary: Comparing different commercial biofertilizer products for their effects as biostimulants, as protectors of plants from drought and plant-pathogenic fungi, can be difficult due to the increasing number of bacteria available in the market. Using a panel of tests, we compared the effects of four commercial strains of the operational group Bacillus amyloliquefaciens to assess their ability to protect pepper plants and stimulate their growth. Then, we obtained numerical values that allow quick diagnoses when choosing a product to ensure that it has the greatest added value or when describing a new strain. The market for bacteria as agricultural biofertilizers is growing rapidly, offering plant-growth stimulants; biofungicides; and, more recently, protectors against extreme environmental factors, such as drought. This abundance makes it challenging for the end user to decide on the product to use. In this work, we describe the isolation of a strain of Bacillus velezensis (belonging to the operational group Bacillus amyloliquefaciens) for use as a plant-growth-promoting rhizobacterium, a biofungicide, and a protector against drought. To compare its effectiveness with other commercial strains of the same operational group, Bacillus amyloliquefaciens, we analyzed its ability to promote the growth of pepper plants and protect them against drought, as well as its fungicidal activity through antibiosis and antagonism tests, its ability to solubilize potassium and phosphates, and its ability to produce siderophores. Finally, we used a probit function, a type of regression analysis used to model the outcomes of analyses, to quantify the biostimulatory effectiveness of the different plant-growth-promoting rhizobacteria, developing what we have called the Agricultural Protection Against Stress Index, which allowed us to numerically compare the four commercial strains of the operational group Bacillus amyloliquefaciens, based on a Delphi method—a type of regression analysis that can be used to model a cumulative normal distribution—and integrate the results from our panel of tests into a single value. [ABSTRACT FROM AUTHOR]

Cyanobacteria are rich producers of secondary metabolites, excreting some of these to the culture media. However, the exometabolome of cyanobacteria has been poorly studied, and few studies have dwelled on its characterization and bioactivity assessment. In this work, exometabolomes of 56 cyanobacterial strains were characterized by HR-ESI-LC-MS/MS. Cytotoxicity was assessed on two carcinoma cell lines, HepG2 and HCT116, while the reduction in lipids was tested in zebrafish larvae and in a steatosis model with fatty acid-overloaded human liver cells. The exometabolome analysis using GNPS revealed many complex clusters of unique compounds in several strains, with no identifications in public databases. Three strains reduced viability in HCT116 cells, namely Tolypotrichaceae BACA0428 (30.45%), Aphanizomenonaceae BACA0025 (40.84%), and Microchaetaceae BACA0110 (46.61%). Lipid reduction in zebrafish larvae was only observed by exposure to Dulcicalothrix sp. BACA0344 (60%). The feature-based molecular network shows that this bioactivity was highly correlated with two flavanones, a compound class described in the literature to have lipid reduction activity. The exometabolome characterization of cyanobacteria strains revealed a high chemodiversity, which supports it as a source for novel bioactive compounds, despite most of the time being overlooked. [ABSTRACT FROM AUTHOR]

This study presents the first genome assembly of the freshwater saprobe fungus Neonectria lugdunensis and a comprehensive phylogenomics analysis of the Nectriaceae family, examining genomic traits according to fungal lifestyles. The Nectriaceae family, one of the largest in Hypocreales, includes fungi with significant ecological roles and economic importance as plant pathogens, endophytes, and saprobes. The phylogenomics analysis identified 2684 single-copy orthologs, providing a robust evolutionary framework for the Nectriaceae family. We analyzed the genomic characteristics of 17 Nectriaceae genomes, focusing on their carbohydrate-active enzymes (CAZymes), biosynthetic gene clusters (BGCs), and adaptations to environmental temperatures. Our results highlight the adaptation mechanisms of N. lugdunensis, emphasizing its capabilities for plant litter degradation and enzyme activity in varying temperatures. The comparative genomics of different Nectriaceae lifestyles revealed significant differences in genome size, gene content, repetitive elements, and secondary metabolite production. Endophytes exhibited larger genomes, more effector proteins, and BGCs, while plant pathogens had higher thermo-adapted protein counts, suggesting greater resilience to global warming. In contrast, the freshwater saprobe shows less adaptation to warmer temperatures and is important for conservation goals. This study underscores the importance of understanding fungal genomic adaptations to predict ecosystem impacts and conservation targets in the face of climate change. [ABSTRACT FROM AUTHOR]

Applying organic waste and inorganic additives during composting can be an effective and easy-to-control strategy for optimizing humification, maturation, and the availability of essential mineral elements in compost. In this respect, this study aims to evaluate the effect of organic (olive-mill waste and horse manure) and inorganic (phosphogypsum) additives on the evolution of maturity indices, aromatic compounds, and nutrient availability during composting. Four mixtures [horse manure + green waste (M1), olive-mill + green waste (M2), sewage-sludge + phos-phogypsum + green waste (M3), and green waste (M4)] were carried out. Physicochemical (temperature, pH, phosphorus, nitrogen, and carbon-to-nitrogen (C/N) ratio), infrared-spectroscopic, and phytotoxicity were monitored. The results showed that (in)organic additives have a positive effect on maturity and humification indices, pH stability, and the phosphorus and nitrogen availability in the composts produced. The horse manure additive reduced the carbon and increased the nitrogen, reducing the C/N ratio. Phosphogypsum and olive-mill reduced phytotoxicity, boosting the nitrogen and phosphorus availability of in composts. Fourier transform infrared spectroscopy (FT-IR) analysis revealed that phosphogypsum and olive-mill addition improved the aromatic compounds and reduced the aliphatic ones in M3 and M4 com-posts. These results suggest new approaches to promoting maturity and stability, as well as phosphorus and nitrogen availability in composts, through better use of organic waste and inorganic additives in composting. [ABSTRACT FROM AUTHOR]

Proper crop rotation determines soil fecundity, which is pertinent for successor crops. With this problem in mind, a study was performed to evaluate the interference of spring wheat (Triticum aestivum L. subsp. aestivum), winter wheat (T. aestivum L. subsp. aestivum), maize (Zea mays L.), and winter rape (Brassica napus L.) as forecrops on the increase in faba bean (Vicia faba L.) and the biochemical and physicochemical properties of the soil. Tests with faba bean were performed in pots in the vegetation hall. The pots were filled with soil from under the abovementioned four plant species, and faba bean was grown. Soil unsown with faba bean was also tested to measure the rhizosphere effect. At the beginning of the experiment, and after its completion, enzymatic and physicochemical analyses of the soil were performed. On the 120th day of the study, faba bean was harvested and biometry was performed. The forecrop substantially influenced the biometric features of the faba bean and the biochemical activity of the soil. Faba beans grown in soil under spring wheat and winter wheat had the highest seed yield, while those grown in soil under the winter rape had the lowest yield. The geometric mean of the enzyme activity index was only significantly positively correlated with the number of faba bean seeds and the soil pH, as well as with the seed dry matter yield and the faba bean plant height. Faba bean cultivation increased the soil biochemical activity. The values of the biochemical and physicochemical parameters of the unsown soil were lower compared to the soil sown with faba bean. The conducted research can help to estimate the changes occurring in arable soils and maintain their stability thanks to the use of appropriate bioindicators, which are the soil enzymes. Moreover, the use of a diversified crop rotation in soil cultivation can provide a lot of information about its function, which can ultimately be used for planning the plant rotation, leading to the improvement of the soil structure and fertility, as well as its protection. [ABSTRACT FROM AUTHOR]

One of the intensively developed tools for cancer therapy is drug-releasing matrices. Polyamidoamine dendrimers (PAMAM) are commonly used as nanoparticles to increase the solubility, stability and retention of drugs in the human body. Most often, drugs are encapsulated in PAMAM cavities or covalently attached to their surface. However, there are no data on the use of PAMAM dendrimers as a component of porous matrices based on polyurethane foams for the controlled release of drugs and biologically active substances. Therefore, in this work, porous materials based on polyurethane foam with incorporated third-generation poly(amidoamine) dendrimers (PAMAM G3) were synthesized and characterized. Density, water uptake and morphology of foams were examined with SEM and XPS. The PAMAM was liquefied with polyether polyol (G441) and reacted with polymeric 4,4′-diphenylmethane diisocyanate (pMDI) in the presence of silicone, water and a catalyst to obtain foam (PF1). In selected compositions, the castor oil was added (PF2). Analogs without PAMAM G3 were also synthesized (F1 and F2, respectively). An SEM analysis of foams showed that they are composed of thin ribs/walls forming an interconnected network containing hollow bubbles/pores and showing some irregularities in the structure. Foam from a G3:G441:CO (PF2) composition is characterized by a more regular structure than the foam from the composition without castor oil. The encapsulation efficiency of drugs determined by the XPS method shows that it varies depending on the matrix and the drug and ranges from several to a dozen mass percent. In vitro biological studies with direct contact and extract assays indicated that the F2 matrix was highly biocompatible. Significant toxicity of dendrimeric matrices PF1 and PF2 containing 50% of PAMAM G3 was higher against human squamous carcinoma cells than human immortalized keratinocytes. The ability of the matrices to immobilize drugs was demonstrated in the example of perspective (Nimesulide, 8-Methoxypsolarene) or approved anticancer drugs (Doxorubicin—DOX, 5-Aminolevulinic acid). Release into the culture medium and penetration of DOX into the tested SCC-15 and HaCaT cells were also proved. The results show that further modification of the obtained matrices may lead to their use as drug delivery systems, e.g., for anticancer therapy. [ABSTRACT FROM AUTHOR]

Vegetable market wastes mixed with the solid waste of cities are significant sources of pollution in India due to their pungent stench and greenhouse gas emissions. The present study assessed the efficacy of optimized biodegradation practice using a large-scale rotary drum composter (5000 L) and a vermicomposter (3000 L) in managing humongous organic waste generated in market areas. The rotary drum reactor was initially commissioned with cow manure before being subjected to a mixture of vegetable waste and dry leaves for 3 months (250 kg/day). The maximum temperatures at the inlet and outlet of the rotary drum were observed to be 78 °C and 45 °C, respectively, providing unequivocal evidence that the reactor developed thermophilic conditions with a 7-day waste retention. The outlet material was then exposed to vermicomposting using Eisenia fetida for just 20 days, which considerably increased the nitrogen content to 4.2%. In addition, the final product was determined to be non-toxic with an SGI% of 98%. Bacterial diversity was studied (16S rRNA) for microbial identification and was found to vary throughout biodegradation. The results indicate that Bacteroidetes, Bacilli, and Proteobacteria dominated the process. Seventy percent of the volume had been lost in 27 days, and the final product was stable and safe for the soil. Thus, optimized biodegradation on a large scale could be a more advanced way for cities to deal with their organic waste. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants generate significant amounts of sludge, a residual product that is rich in nutrients, usually considered waste, and traditionally eliminated by storage or incineration, methods that are expensive, environmentally damaging, and often unsustainable. Composting is increasingly recognized as an ecological and durable solution for managing biodegradable waste, including sludge resulting from wastewater treatment. The composting of residual sludge usually requires mixing with bulking agents, such as green waste or agricultural residues, to ensure a well-balanced carbon–nitrogen ratio. This mixture undergoes a controlled aerobic decomposition, sometimes followed by post-treatment, resulting in a stabilized final product that is nutrient-rich and pathogen-free and can be used as soil amendment or fertilizer in different agricultural or landscaping applications. By using composting, communities can reduce elimination costs, reduce greenhouse gas emissions, and minimize the environmental impact of sludge management. This paper reviews recent reported experiences in the laboratory regarding full-scale sludge composting, highlighting the particularities of the processes, the influence factors, the quality of the final product, and the environmental and regulatory constraints. Composting is a sustainable and ecological solution for managing wastewater sludge, contributing to nutrient circularity, and minimizing the environmental impact. [ABSTRACT FROM AUTHOR]

Background: Penicillium oxalicum is an important fungal agent in the composting of cattle manure, but the changes that occur in the microbial community, physicochemical factors, and potential functions of microorganisms at different time points are still unclear. To this end, the dynamic changes occurring in the microbial community and physicochemical factors and their correlations during the composting of cattle manure with Penicillium oxalicum were analysed. Results: The results showed that the main phyla observed throughout the study period were Firmicutes, Actinobacteria, Proteobacteria, Bacteroidetes, Halanaerobiaeota, Apicomplexa and Ascomycota. Linear discriminant analysis effect size (LEfSe) illustrated that Chitinophagales and Eurotiomycetes were biomarker species of bacteria and eukaryote in samples from Days 40 and 35, respectively. Bacterial community composition was significantly correlated with temperature and pH, and eukaryotic microorganism community composition was significantly correlated with moisture content and NH4+-N according to redundancy analysis (RDA). The diversity of the microbial communities changed significantly, especially that of the main pathogenic microorganisms, which showed a decreasing trend or even disappeared after composting. Conclusions: In conclusion, a combination of high-throughput sequencing and physicochemical analysis was used to identify the drivers of microbial community succession and the composition of functional microbiota during cattle manure composting with Penicillium oxalicum. The results offer a theoretical framework for explaining microecological assembly during cattle manure composting with Penicillium oxalicum. [ABSTRACT FROM AUTHOR]

Some plant-associated microorganisms could improve host plants biotic and abiotic stress tolerance. Imperata cylindrica is a dominant pioneer plant in some abandoned mine lands with higher concentrations of heavy metal (HM). To discover the specific microbiome of I. cylindrica in this extreme environment and evaluate its role, the microbiome of I. cylindrica’s seeds and rhizosphere soils from HM heavily contaminated (H) and lightly contaminated (L) sites were studied. It was found that HM-contamination significantly reduced the richness of endophytic bacteria in seeds, but increased the abundance of resistant species, such as Massilia sp. and Duganella sp. Spearman’s rank correlation coefficient analysis showed that both Massilia sp. and Duganella sp. showed a significant positive correlation with Zn concentration, indicating that it may have a strong tolerance to Zn. A comparison of the microbiome of rhizosphere soils (RS) and adjacent bare soils (BS) of site H showed that I. cylindrica colonization significantly increased the diversity of fungi in rhizosphere soil and the abundance of Ascomycota associated with soil nutrient cycling. Spearman’s rank correlation coefficient analysis showed that Ascomycota was positively correlated with the total nitrogen. Combined with the fact that the total nitrogen content of RS was significantly higher than that of BS, we suppose that Ascomycota may enhance the nitrogen fixation of I. cylindrica, thereby promoting its growth in such an extreme environment. In conclusion, the concentration of HM and nutrient contents in the soil significantly affected the microbial community of rhizosphere soils and seeds of I. cylindrica, in turn, the different microbiomes further affected soil HM concentration and nutrient contents. The survival of I. cylindrica in HM severely contaminated environment may mainly be through recruiting more microorganisms that can enhance its nutrition supply. [ABSTRACT FROM AUTHOR]