Search Results (429)

Conventional and organic agriculture can both cause soil microbial community structure (SMCS) destruction, infertility, and abandonment. The application of soil productivity-improving biofertilizers is a sustainable practice that requires holistic knowledge, including complex biointeractions, diverse microbial metabolism, and culture requirements, the last of which rely on methodology and technology. In this study, a holistic culture-based and meta-analysis approach was employed to explore pristine and domesticated soils for presumptive plant growth-promoting (PGP) bacteria. Various soil samples were logistically acquired and processed using enrichment and heat alternatives. Morphologically diverse isolates were streak-purified and analyzed for 16S rRNA bacterial identification. Meta-analysis of PGP bacteria in domesticated environments was conducted using Google Search and NCBI PubMed. Soil fertility was analyzed for the pH and nitrogen/phosphorus/potassium (NPK) contents using biochemical tests. Notably, 7 genera and 15 species were differentially recovered, with Bacillus being the most prevalent and diverse in species. Conversely, Aeromonas, Lactobacillus, Lelliottia, Pseudomonas, and Staphylococcus were found only in pristine soil. While soil pH was consistent in all pristine soil samples, NPK contents ranged widely across the pristine (i.e., P/K) and domesticated samples (i.e., N/P/K). These findings could enhance biofertilizer SMCS, function, and effectiveness in the agricultural productivity needed to feed the expanding population. Full article

Oats (Avena sativa L.) are a staple grain and forage crop with substantial market demand. In China, they are the second most-imported forage grass, only after alfalfa (Medicago sativa L.). Enhancing the salt tolerance of oats to facilitate their cultivation in saline areas can thereby increase forage yield and promote the utilization of saline land, which constitutes an important reserve land resource in China. This study aimed to identify the bacterial strain Bacillus sp. LrM2 (hereafter referred to as strain LrM2) to determine its precise species-level classification and evaluate its effects on oat photosynthesis and growth under salt stress through indoor pot experiments. The results indicated that strain LrM2, capable of urease production and citrate utilization, was identified as Bacillus mojavensis. The strain LrM2 had a positive effect on shoot and root growth of oats under 100 mM NaCl stress conditions. Strain LrM2 inoculation modulated osmotic stress in oats under 100 mM NaCl stress by significantly increasing soluble sugar and decreasing proline content in leaves. It inhibited Na⁺ uptake and promoted K⁺ absorption in the roots, thereby reducing Na⁺ translocation to the leaves and mitigating ionic toxicity. Inoculation with strain LrM2 significantly increased photosynthetic pigment content (chlorophyll a, carotenoids), improved gas exchange parameters (stomatal conductance, transpiration rate, net rate of photosynthesis), enhanced PSII photochemical efficiency (maximum quantum yield, coefficient of photochemical quenching, actual photosynthetic efficiency of PSII, electron transfer rate), and reduced the quantum yield of non-regulated energy dissipation. These improvements, coupled with increased relative water content and instantaneous water use efficiency, thereby collectively enhanced the overall photosynthetic performance. In conclusion, strain LrM2 represents a promising bio-resource for mitigating salt stress and promoting growth in oats, with direct applications for developing novel biofertilizers and sustainable agricultural strategies. Full article

Plant growth-promoting bacteria (PGPB) could exert positive effects on plant growth and productivity; however, little is known about the effects of variables during the production of PGPB biomass and how they could affect the performances of these microorganisms. This study investigated the effects of pH, temperature, and culture age on the growth of promising PGPBstrains, Bacillus sp. 36M and Stenotrophomonas sp. 20P, isolated from the rhizosphere of durum wheat. A fractional factorial 2^k design was applied to evaluate bacterial growth under varying conditions (pH 5.0–7.5; 15–35 °C; 24–72 h precultures). Multifactorial ANOVA revealed that all independent variables and their interactions significantly affected cell concentration (p < 0.05). Bacillus sp. 36M exhibited optimal growth when inoculated from 24 h cultures and incubated under moderate conditions (15 °C, pH 7.5), whereas Stenotrophomonas sp. 20P showed higher viability with 72 h cultures. These results demonstrate that the inoculum physiological state is a critical determinant of PGPB stress tolerance and should be specifically optimized for each strain. The greater technological robustness of Stenotrophomonas sp. 20P suggests its suitability for biofertilizer formulations requiring extended shelf-life or application under variable environmental conditions. In conclusion, this work provides a quantitative framework for tailoring PGPB production protocols to maximize field performance in sustainable agriculture. Full article

Moringa oleifera has been recognized for its adaptability, nutritional richness, and multipurpose potential, particularly in resource-limited regions. While most research has focused on its leaves, moringa seeds remain underutilized despite their broad applicability in the environmental, agricultural, and food sectors. This review systematically and critically examines recent scientific literature on the use of M. oleifera seeds across these fields, emphasizing their functional value, applications, and challenges for sustainable use. The review follows the SALSA methodology (Search, Appraisal, Synthesis, and Analysis), a structured and iterative framework designed to identify, evaluate, and integrate scientific evidence from diverse sources. The analysis encompasses three main areas: (i) water treatment, where moringa seed extracts have achieved turbidity removal efficiencies above 90% and effective adsorption of dyes and potentially toxic elements; (ii) agriculture, where seed-derived fertilizers improve soil fertility, nutrient availability, and crop yield compared to conventional inputs; and (iii) the food industry, where moringa seed derivatives enhance the nutritional, functional, and antioxidant properties of bakery, beverage, and oil-based products. Overall, M. oleifera seeds emerge as a versatile and sustainable resource with proven potential as a natural coagulant, biofertilizer, and nutraceutical ingredient. By integrating findings from both English and Spanish language studies, this work highlights their contribution to sustainable water management, agricultural productivity, and food innovation, while emphasizing the need for further safety evaluation and process optimization to support large-scale application. Full article

Agricultural production is consistently threatened by stressors such as salinity. Few studies have reported on the released antioxidative enzymes and the salinity-responsive genes identified using RNA sequencing and de novo assembly in maize. To further understand the harmony between stressing the maize with a NaCl solution as a compensatory water-irrigation method and spraying regulatory zinc oxide nanoparticles (ZnO/NPs), the salinity-responsive genes were analyzed using RNA sequencing and bioinformatics tools, and the antioxidant enzymatic activities were determined. Differential expression analysis was used to uncover genes that were up-/down-regulated during the experiment. The regulatory pathways and functions of differentially expressed genes (DEGs) were estimated. Glutathione reductase/-s-transferase (GR/GST), peroxidase (POX), superoxide dismutase (SOD), and catalase (CAT) enzymes were determined spectrophotometrically. Mitigating salinity stress with 150 mM NaCl led to significant oxidative stress, markedly elevating enzyme activities: POX and GST by 275% and 254%, GR by 166%, CAT by 91%, and SOD by 56%. Treatment with ZnO/NPs alleviated this stress, decreasing enzyme activity by 61% for GST, 55% for POX, 38% for CAT, 28% for SOD, and 25% for GR. The results of RNA-seq revealed candidate genes related to changes in stressed/non-stressed maize plants, regardless of whether they were sprayed with the nanoparticles or not. This study’s results offer novel insights into the genetic traits of maize subjected to salinity stress and ZnO/nanoparticle application, thereby advancing the comprehension of how ZnO/nanoparticles might alleviate the detrimental impacts of salinity on plants whose properties were enhanced to be used in the eco-friendly synthesis of nanoparticles that were used as a bio-fertilizer in priming plants. Full article

This systematic review aimed to examine recent advances (2021–2025) in the conversion of agricultural biomass into biomaterials, biofertilizers, and bioproducts. Studies were included when addressing biomass types, pretreatment methods, conversion technologies, or resulting applications. Non-agricultural biomass, non-original research, and works outside the defined timeframe were excluded. Literature was identified in Scopus and Web of Science, complemented by Espacenet, Google Scholar, and institutional databases (USDA, FAO, IRRI, ABARES, UNICA, and CONAB, among others), totaling 108 documents referenced in this work. Risk of bias was minimized through predefined eligibility criteria and full-text assessment. Results were narratively synthesized, supported by figures and tables highlighting technological trends. Studies involving a wide range of agricultural biomasses (e.g., rice straw, corn stover, wheat straw, and sugarcane bagasse) were evaluated. Main outcomes included the development of bioplastics, biofoams, composites, hydrogels, bioceramics, biochar-based fertilizers, organic acids, enzymes, and green solvents. Evidence consistently indicated that pretreatment strongly influences conversion efficiency and that enzymatic and thermochemical routes show the highest potential for integrated biorefineries. Limitations included heterogeneity in biomass composition, variability in methodological quality, and scarcity of large-scale studies. Overall, findings underscore agricultural biomass as a strategic feedstock for circular bioeconomy models, with implications for sustainable materials, renewable energy, and low-carbon agriculture. Continued innovation, supportive policies, and improved logistics are essential for scaling biomass-based technologies. Full article

The agro-industrial sector in Indonesia produces significant amounts of nutrient-rich waste and wastewater, which pose environmental risks but also present opportunities for valorization within a circular bioeconomy. Microalgae provide a promising solution for transforming these wastewaters into valuable products such as biomass for bioenergy, biofertilizers, or pigments, all while helping to remediate pollutants. This review synthesizes current knowledge on the use of major Indonesian agro-industrial effluents, specifically palm oil mill effluent (POME), byproducts from cassava and sugarcane, and soybean residues, as substrates for microalgal biomass production and cultivation. Furthermore, various cultivation strategies are summarized, including autotrophic, heterotrophic, and mixotrophic methods, as well as the use of open ponds, photobioreactors, and hybrid systems. These cultivation processes influence biomass yield, metabolite production, and nutrient removal. Reported studies indicate high removal efficiencies for organic loads, nitrogen, and phosphorus, along with considerable production of lipids, proteins, pigments, and biofuels. Yet, effluent pretreatment, concerns about heavy metal and pathogen contamination, high downstream processing costs, and biosafety issues remains as challenges. Nonetheless, the application of microalgal cultivation into Indonesia’s agro-industrial wastes treatment can provide the dual benefits of waste mitigation and resource recovery, helping to advance climate goals and promote rural development. Full article

Soil salinization poses a significant threat to agricultural sustainability. This study investigated the effects of different microbial fertilizers on the rhizosphere fungal community and physicochemical properties of saline–alkali soil cultivated with sunflower. Three microbial fertilizers were applied at three concentration gradients to two sunflower varieties with contrasting salt–alkali tolerance (salt-tolerant NX53177 and salt-sensitive NKY1502) to elucidate the mechanisms underlying microbial fertilizer-mediated amelioration of saline–alkali soils. Among all treatments, the application of Aikesa microbial fertilizer at 50 g per pot (treatments T8 and T17) demonstrated the most pronounced ameliorative effects. In the salt-tolerant variety NX53177, the 50 g/L Aikesa fertilizer treatment increased the relative abundance of the beneficial genus Mortierella by 46.2%. It decreased the potentially pathogenic genus Lophotrichus by 82.2% compared to the no-fertilizer control. Soil fungal diversity was significantly improved, with the Shannon index increasing by 9.86% and the Simpson index decreasing by 25.83%. Concurrently, critical soil properties were enhanced: soil pH decreased by 7.79%, salinity decreased by 3.13%, and the contents of organic matter, available nitrogen, available phosphorus, and available potassium increased by 42.13%, 49.96%, 12.34%, and 53.22%, respectively. In the salt-sensitive variety NKY1502, the 50 g/L Aikesa fertilizer treatment increased Mortierella abundance by 15.96% and decreased Lophotrichus by 73.6% compared to the no-fertilizer control. The ACE and Shannon diversity indices increased by 10.00% and 9.92%, respectively, while the Simpson index decreased by 12.17%. Soil health was also markedly improved, with pH decreasing by 7.47%, salinity by 2.95%, and substantial increases in organic matter (57.94%), available nitrogen (75.78%), available phosphorus (13.20%), and available potassium (52.97%). In conclusion, the 50 g/L Aikesa fertilizer treatment effectively improved the rhizosphere fungal community structure and significantly enhanced soil physicochemical properties under saline–alkali stress. These findings provide a theoretical foundation and practical guidance for utilizing microbial fertilizers in ecological restoration and sustainable agricultural development of saline–alkali lands. Full article

Spent bleaching earths (SBEs) resulting from the refining of soybean oil contain significant amounts of residual oil and phosphorus, which pose an environmental and disposal problem. In this study, a sustainable biotechnological approach to reactivate SBEs through enzymatic hydrolysis with a commercial lipase under moderate conditions was investigated. In an initial 2³ factorial experimental design, the effects of temperature (40–60 °C), enzyme amount (50–200 mg), and reaction time (4–8 h) were evaluated, with reaction time identified as statistically significant (p < 0.05). A second experimental design with lower enzyme concentrations (5–25 mg) validated a positive effect of enzyme dosage on phosphorus removal. This result was validated by a presence/absence test in which no phosphorus removal occurred in the absence of the biocatalyst. The best conditions (60 °C, 4 h, 5 mg enzyme) reduced the oil content from 10% to 5% and achieved 97% phosphorus removal. However, pigment removal efficiency was limited to approximately 34%, indicating partial restoration of the bleaching capacity compared to virgin earth. The enzymatic process also produced a nutrient-rich liquid hydrolysate containing Mg (16 mg/L), P (750 μg/L), and S (980 μg/L), suggesting potential use as a biofertilizer. Regenerated SBE demonstrated suitability for reuse in oil bleaching systems and potential applications in filtration and soil conditioning, providing a cost-effective and environmentally friendly alternative to conventional regeneration methods. Full article

Microorganisms are considered a potential source of biofertilizers for mobilizing nutrients from insoluble mineral potassium (K). This study was conducted to evaluate the effects of liquid potassium-solubilizing bacteria, Cereibacter sphaeroides M-Sl-09, Rhodopseudomonas thermotolerans M-So-11, and Rhodopseudomonas palustris M-So-14 (LPS-PNSB), on soil K content, plant K uptake, growth, and yield of hybrid maize cultivated on alluvial soil in the dyke-protected area of An Phu, An Giang, Vietnam. Results showed that the application of LPS-PNSB significantly improved exchangeable soil K from 0.428 to 0.460–0.470 meq 100 g⁻¹, total plant K uptake from 181.5 to 205.8–259.4 kg ha⁻¹, and yield from 11.1 to 12.2–12.6 ton ha⁻¹, compared with the recommended 100% NPK fertilization. The addition of LPS-PNSB allowed a 100% reduction in K fertilizer compared with the recommended rate while still maintaining yield. Hybrid maize grain yield further increased when 100% recommended K was applied in combination with LPS-PNSB, surpassing the yield obtained with 100% K alone. Full article

This study examines the antioxidant status of four Nostoc and Desmonostoc strains during long-term cultivation in nitrogen-depleted media. Growth rates, retinol and α-tocopherol content, fatty acid composition, and activities of antioxidant enzymes were analysed. The results showed that all tested strains adapted to nitrogen limitation using various cellular mechanisms. Specifically, the strain Nostoc sphaeroides exhibited the highest specific growth rate and elevated glutathione peroxidase activity. The Nostoc commune and Desmonostoc caucasicum strains displayed higher superoxide dismutase activity, suggesting robust antioxidative capabilities. Additionally, Desmonostoc caucasicum exhibited unique adaptive strategies, such as elevated succinate dehydrogenase activity. Generally, fatty acid composition changes showed divergent lipid peroxidation vulnerabilities among the studied strains. Principal component analysis highlighted clear distinctions among the strains in terms of their antioxidant capacities and metabolic adjustments. High retinol content correlated positively with increased catalase activity and fatty acid saturation, whereas α-tocopherol concentration was linked to succinate dehydrogenase activity. The obtained results underscore the robustness of cyanobacterial antioxidant defence systems and highlight their metabolic adaptations under nitrogen deprivation. Understanding these responses offers insight into potential biotechnological applications, such as biofertilizers or therapeutics. Full article

A field study was conducted on the plants of two grapevine cultivars, ‘Solaris’ and ‘Regent’, grafted onto an SO 4 rootstock (V. berlandieri × V. riparia) and characterized by strong growth and yield. The effect of twelve treatments on the concentration of macroelements in leaf blades in the véraison phase, as well as selected soil parameters, was assessed in the sixth, seventh and eighth year of their application. The following treatments were tested: control (no fertilization), NPK (mineral fertilization 70 kg N/ha; 40 kg P/ha; 120 kg K/ha), mycorrhizal substrate (AMF—arbuscular mycorrhizal fungi), NPK + AMF, manure before planting, NPK + manure before planting, BioIlsa, NPK + BioIlsa, BF-Ecomix, NPK + BF-Ecomix, Ausma, NPK + Ausma. The aim of the study was to assess the nutritional status of the two cultivars after long-term use of mineral fertilizers, organic fertilizers, biofertilizers and biostimulants under Polish conditions in soil with a low organic matter (SOM) content prone to acidification. AMF, organic fertilizers and biostimulants were not a sufficient alternative to mineral fertilizers, especially with regard to N supply. BF-Ecomix treatment increased the content of Mg in the soil and the soil pH value. Regular use of NPK fertilization increased the concentration of leaf N and K, but did not improve the nutritional status of plants with P, despite doubling its content in the soil compared to control. NPK fertilizers worsened the availability and accumulation of Mg and caused soil acidification, but resulted in a slight increase in total soil N and SOM. No significant differences were noted in the mineral status of both cultivars under the same fertilization treatments but liming improved the leaf Ca status in ‘Solaris’. Fertilization of grapevines, which have started to be cultivated in Poland due to the warming climate, requires further study. Mineral fertilization should not be routine, but rather constantly readjusted, taking into account the soil fertility and mineral status of plants, in order to use the nutrients more effectively and avoid their unfavorable effects on plants and soil. Full article

Potassium (K) is present in soils mainly in minerals, including feldspar. However, most of it is unavailable to plants. In the in-dyked alluvial soils of the Mekong Delta, available K is typically low despite the abundance of K-bearing feldspar, leading to nutrient imbalances and yield constraints. This study aimed to (i) select potential feldspar-potassium-solubilizing purple nonsulfur bacteria (K-PNSB), (ii) determine their ability to enhance hybrid maize seed vigor (Zea mays L.), and (iii) evaluate their effects on the growth of maize seedlings. Fifty-eight K-PNSB strains were isolated from maize-cultivated in-dyked alluvial soils, with soluble K concentrations ranging from 0.108 to 15.0 mg L⁻¹. Among these, strain M-Sl-03 released the highest K concentration under microaerobic light conditions, whereas strains M-Sl-01 and M-Sl-06 produced best under aerobic dark conditions. In addition, two more strains, M-Sl-02 and M-Wa-06, were also selected for their K solubilization ability. The selected strains were identified as Cereibacter sphaeroides strains M-Sl-01 and M-Sl-02, Rhodopseudomonas palustris strain M-Sl-03, and Rhodoplanes pokkaliisoli strains M-Sl-03 and M-Wa-06, according to their 16S rDNA region. None of them exhibited toxicity to germinating maize seeds. Both individual strains and the five-strain mixture significantly improved seed vigor. At a 1:1000 dilution, individual and mixed inoculants increased the vigor index of maize seeds by 47.5–68.8%. In addition, the selected PNSB strains contributed to improving the growth of maize seedlings, particularly plant height and root dry biomass. These promising strains have potential for application as biofertilizers to support hybrid maize cultivation. Full article

China has promoted renewable energy development to adjust its energy structure and improve energy security. The decision-makers consider manure-to-energy a feasible possibility because manure contains a substantial amount of organic materials that are potentially useful for generating power, and its use would also alleviate environmental pressures. Southern China, including Anhui, Fujian, Guangdong, and Zhejiang provinces, has launched policies to support manure facilities and energy sales. This study employs a lifecycle analysis and techno-economic assessment to evaluate whether manure application could be an economically feasible alternative. The results indicate that the thermophilic system has greater energy potential, and the mesophilic mode can yield greater agronomic benefits with digestate application. Hog manure can generate biopower ranging from 5599 to 5683 GWh, and it is 653 to 1887 GWh for cattle, 2481 to 2963 GWh for poultry manure, and 1109 to 1536 GWh for sheep manure. The aggregate emission offset could also be substantial. If all manures are properly utilized, the net emission offset could be up to 12.07 million metric tons of CO₂ equivalent, with an aggregate energy revenue of approximately USD 1086 million annually. In addition to the aggregate result, this study also indicates that manure application would yield a profit ranging from USD 8.36 to USD 34.3, and the benefit from biofertilizer would be roughly between USD 27.72 and USD 43.49. Nevertheless, regional characteristics, such as temperature, precipitation, and soil quality, generally influence agricultural systems, and the benefits associated with agrarian feedback would involve a higher uncertainty. On the contrary, energy sales could be considered a more reliable and stable source of income, even without government subsidies. Full article

The recovery of livestock waste through multistage anaerobic digestion represents a key strategy for producing high-efficiency liquid biofertilizers within circular economy frameworks. This study compared two underexplored substrates—guinea pig manure and vermicompost leachate (VL)—processed in series biodigesters to evaluate their nutrient composition and agronomic performance. The guinea pig manure biol exhibited higher macronutrient concentrations (N = 1.09–3.74 g L⁻¹; P = 0.06–0.64 g L⁻¹; K = 1.85–3.20 g L⁻¹) and electrical conductivity (14.1–26.5 mS cm⁻¹), while VL presented a more balanced nutrient profile (N = 0.65–0.71 g L⁻¹; P = 0.04–0.09 g L⁻¹; K = 2.46–3.76 g L⁻¹) and slightly lower salinity (15.0–17.2 mS cm⁻¹). Micronutrient levels (Fe, Mn, Zn, B) exceeded the reference thresholds established by EU Regulation 2019/1009 for liquid fertilizers, suggesting the need for dilution prior to field application. In maize field trials, VL diluted 1:7 increased above-ground biomass by 28%, and guinea pig biol diluted 1:10 achieved a 22% increase compared to the control, confirming their biostimulant potential. However, the high sodium content (848–1024 mg L⁻¹) may limit application on saline or poorly drained soils, requiring adaptive agronomic management. These findings demonstrate that multistage anaerobic digestion effectively transforms unconventional organic waste into nutrient-rich biofertilizers, expanding the scientific foundation for alternative substrates and reinforcing their potential to enhance Andean smallholder agriculture, nutrient recycling, and food security within a sustainability-oriented bioeconomy. Full article