Search Results (281)

Apples and tomatoes are among the most consumed products all over the world, as well as the natural juices prepared from each of them. The large quantities of resulting by-products should be reused in various directions within the circular economy. In this study, apple and tomato pomaces were tested as potential biofertilizers for agricultural crops. To this end, aqueous extracts of apple pomace and tomato pomace were prepared in two concentrations (0.05% and 0.5%) and used to treat wheat caryopses and sprouts. The following were evaluated: mitotic index, genotoxic index, caryopses germination rate, and wheat sprout growth. The biotic response of wheat to treatments with the apple and tomato pomace extracts consisted of reduced mitotic activity, i.e., cytotoxicity, and the formation of genetic abnormalities, i.e., genotoxicity. The cytotoxicity and the genotoxicity were reflected at the macro level in phytotoxic effects, manifested by a reduction in the germination rate of caryopses and a decrease in the length of wheat roots and shoots. Physiological parameters were positively correlated with the mitotic index and negatively correlated with the genotoxic index. The obtained results point us not to recommend the use of unprocessed apple and tomato pomaces as biofertilizers, but, on the contrary, as bioherbicides. Full article

This research provides a comprehensive evaluation of the phytochemical composition, antioxidant potential, and biological properties of four plant species with longstanding use in ethnobotanical traditions: Calendula officinalis, Mentha × piperita, Urtica dioica, and Juglans regia. Plant extracts were obtained using a range of solvent systems and subsequently analyzed for their content of total polyphenols, flavonoids, and phenolic acids. Ultra-high-performance liquid chromatography coupled with mass spectrometry (UHPLC-MS) enabled the accurate identification and quantification of major polyphenolic constituents. The antioxidant capacity was assessed through a series of in vitro assays, and elemental analysis was conducted to determine microelement content. To evaluate potential ecological implications, acute toxicity was tested using Daphnia magna, while phytotoxic effects were also examined. The results demonstrate pronounced antioxidant activity along with notable biocidal and soil-enhancing properties. These findings underscore the potential of such plant-based formulations as sustainable alternatives to conventional agrochemicals and highlight the relevance of integrating traditional botanical knowledge with modern strategies for enhancing soil quality, crop performance, and environmental sustainability. Full article

In this study, the effects of composting phase and bulking agent on macronutrient extraction and the chemical, physicochemical, and biological properties of 20 compost teas from poultry waste composting mixtures were evaluated. Phosphorus (P) extraction was more efficient during stabilization after the thermophilic phase; however, water-soluble P declined as composting progressed. K was more amenable to extraction, with yields ranging from 30% to 70%, followed by N (2% to 12%) and P (1% to 7%). Compost tea quality was clearly affected by both the bulking agent and the composting stage. Bulking agents that accelerate the process, such as cotton waste (CW) and Napier grass (NG), contributed to nutrient mineralization, increasing availability in the compost tea but also raising salt contents responsible for phytotoxicity. In contrast, tree trimmings (TT), sawdust (S), and sugarcane bagasse (SCB) showed better results, striking a balance between nutrient availability and salt content. The period between the thermophilic phase and cooling was the most suitable for extraction, providing the greatest contribution of water-soluble nutrients. This study highlights the influence of bulking agents and composting phases on nutrient extraction and phytotoxicity of compost teas and provides new insights into the role of electrical conductivity as a threshold indicator for safe agricultural application. Full article

Endophytic fungi (EF) are microorganisms that colonize the internal tissues of host plants, providing a range of benefits to them. In this symbiosis, they act as a reservoir of bioactive metabolites that are important for enhancing the host’s defense mechanisms as a resistance against pathogens. These molecules usually possess antimicrobial properties that can be exploited for application in agriculture and medicine. In this context, the current work was designed to evaluate the phytotoxic and antimicrobial properties of the endophytic fungus Curvularia inaequalis, isolated for the first time from the Iranian medicinal plant Echium khuzistanicum. Culture filtrates, their organic extracts, and isolated metabolites were tested against a series of plants to assess their phytotoxicity, as well as against a wide range of plant and human pathogens to evaluate their antimicrobial activity. The main compounds characterizing the organic extract of C. inaequalis have been identified as (R)-phomalactone, catenioblin A, and (-) asperpentyn (1–3) by using spectroscopic techniques, NMR mainly, and HR-ESI-MS. In the bioactivity evaluation carried out in this study, (R)-phomalactone (1) stood out as the most promising compound, exhibiting significant non-host phytotoxic activity on tomato leaves; potent antibacterial activity against a wide range of human pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) strains; and marked antifungal activity against several economically important phytopathogens. (–)-Asperpentyn (3) also showed robust and selective antifungal activity against phytopathogens, while catenioblin A (2) exhibited only a slight phytotoxic effect and limited overall bioactivity in this study. These findings reveal that the isolated endophytic fungi hold considerable promise as an untapped source of bioactive metabolites with antibacterial, antifungal, and phytotoxic activities. Full article

Phytopathogenic fungi represent a significant biotic stress affecting global agriculture, often causing severe diseases and, in some cases, leading to plant death. They have been isolated from economically important crops, including cereals, legumes, and fruits. Among the compounds produced by fungi, phytotoxins play a key role in disease development by interfering with host physiological processes. In this study, organic extracts from Cercospora kikuchii, Cercospora nicotianae, Cercospora sojina, Diaporthe longicolla, Septoria glycines, Pyrenophora teres, and Pyrenophora tritici-repentis, isolated from three major Argentine crops, were first screened for the in vitro production of phytotoxic metabolites. Subsequently, selected metabolites were dereplicated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and nuclear magnetic resonance (NMR) spectroscopy. The phytotoxins identified varied according to the fungal species and extraction conditions. Cercosporin, putaminoxin, scytalone, and isosclerone were identified. These findings underscore the need for further chemical investigation to comprehensively characterize the metabolome of these phytopathogens and clarify their roles in plant–pathogen interactions. Full article

Development of new sustainable pesticides represents a real challenge for researchers due to environmental issues and public health aspects. In fact, the overuse of chemical pesticides has led to environmental damage, loss of biodiversity, and pesticide-resistant pests. In a framework characterized by the necessity of new sustainable agricultural practices, this study investigates the plant Genista ulicina as a producer of bioactive compounds for potential application as eco-friendly biopesticides. First, both roots and aerial parts of G. ulicina were extracted and the main compounds in the crude extracts were identified via GC-MS. Subsequently, the crude extracts were submitted to antifungal and phytotoxic assays. In particular, the antifungal effects were evaluated on three common phytopathogenic fungi, Fusarium oxysporum, Alternaria alternata, and Botrytis cinerea, while phytotoxic activity was evaluated on two weed species: Euphorbia peplus L. and Oxalis corniculata L. Further insights were obtained on the herbicidal potential of phytochemical compounds produced by G. ulicina through in silico investigations. In particular, molecular docking analyses were performed against three key enzymes involved in essential plant metabolic pathways: acetohydroxyacid synthase (AHAS), 4-hydroxyphenylpyruvate dioxygenase (HPPD), and protoporphyrinogen oxidase (PPO). Among the compounds identified, linolelaidic acid methyl ester, 1-monolinolein, stearic acid, and palmitic acid derivatives showed promising binding affinities and favorable interaction patterns compared to reference ligands. Selected phytochemicals from G. ulicina show potential as inhibitors of key herbicide targets, suggesting their value as promising leads in the development of sustainable bio-based weed control agents. Full article

The accumulation of agricultural residues presents an environmental challenge. PBLs have emerged as effective agents for biodegrading such biomass, producing frass rich in HA with low phytotoxicity, positioning it as a potential biofertilizer. However, the influence of PBL bioconversion on HA yields and microbial communities across different substrates remains underexplored. In this research, PBL is fed on two Pleurotus SMSs and oak sawdust. The resulting frass was characterized and showed low phytotoxicity based on seed germination and plant growth. The extracted HA quantity and quality were significantly higher in frass than diet samples. Microbial profiling using 16S rRNA gene high-throughput sequencing revealed the enrichment of potential PGP genera, including Pseudoxanthomonas, Cellulomonas, Flavobacterium, and Mucilaginibacter. In addition, the actino-genera Cellulomonas, Demequina, Xylanimicrobium, Mycolicibacter, Nakamurella, and Glutamicibacter were positively correlated with HA content and quality parameters. This study highlights the potential of PBL systems in waste valorization and biofertilizer production as a novel approach for sustainable agriculture. Full article

This study aimed to evaluate solid-state fermentation (SSF) as a sustainable approach for the simultaneous detoxification of olive pomace (OP) and the production of industrially relevant enzymes. OP, a semisolid byproduct of olive oil extraction, is rich in lignocellulose and phenolic compounds, which limit its direct reuse due to phytotoxicity. A native strain of Aspergillus sp., isolated from OP, was employed as the biological agent, while grape pomace (GP) was added as a co-substrate to enhance substrate structure. Fermentations were conducted at two scales, Petri dishes (20 g) and a fixed-bed bioreactor (FBR, 2 kg), under controlled conditions (25 °C, 7 days). Key parameters monitored included dry and wet weight loss, pH, color, phenolic content, and enzymatic activity. Significant reductions in color and polyphenol content were achieved, reaching 68% in Petri dishes and 88.1% in the FBR, respectively. In the FBR, simultaneous monitoring of dry and wet weight loss enabled the estimation of fungal biotransformation, revealing a hysteresis phenomenon not previously reported in SSF studies. Enzymes such as xylanase, endopolygalacturonase, cellulase, and tannase exhibited peak activities between 150 and 180 h, with maximum values of 424.6 U·g⁻¹, 153.6 U·g⁻¹, 67.43 U·g⁻¹, and 6.72 U·g⁻¹, respectively. The experimental data for weight loss, enzyme production, and phenolic reduction were accurately described by logistic and first-order models. These findings demonstrate the high metabolic efficiency of the fungal isolate under SSF conditions and support the feasibility of scaling up this process. The proposed strategy offers a low-cost and sustainable solution for OP valorization, aligning with circular economy principles by transforming agro-industrial residues into valuable bioproducts. Full article

Alperujo, a solid by-product from the two-phase olive oil extraction process, poses significant environmental challenges due to its high organic load, phytotoxicity, and phenolic content. At the same time, it represents a promising feedstock for recovering value-added compounds such as phenols and volatile fatty acids (VFAs). When used as a substrate for white rot fungi (WRF), it also produces ligninolytic enzymes. This study explores the use of two native WRF, Anthracophyllum discolor and Stereum hirsutum, for the biotransformation of alperujo under solid-state fermentation conditions, with and without supplementation of copper and manganese, two cofactors known to enhance fungal enzymatic activity. S. hirsutum stood out for its ability to release high concentrations of phenolic compounds (up to 6001 ± 236 mg gallic acid eq L⁻¹) and VFAs (up to 1627 ± 325 mg L⁻¹) into the aqueous extract, particularly with metal supplementation. In contrast, A. discolor was more effective in degrading phenolic compounds within the solid matrix, achieving a 41% reduction over a 30-day period. However, its ability to accumulate phenolics and VFAs in the extract was limited. Both WRF exhibited increased enzymatic activities (particularly Laccase and Manganese Peroxidase) with the addition of Cu-Mn, highlighting the potential of the aqueous extract as a natural source of biocatalysts. Phytotoxicity assays using Solanum lycopersicum seeds confirmed a partial detoxification of the treated alperujo. However, none of the fungi could entirely eliminate inhibitory effects on their own, suggesting the need for complementary stabilization steps before agricultural reuse. Overall, the results indicate that S. hirsutum, especially when combined with metal supplementation, is better suited for valorizing alperujo through the recovery of bioactive compounds. Meanwhile, A. discolor may be more suitable for detoxifying the solid phase strategies. These findings support the integration of fungal pretreatment into biorefinery schemes that valorize agroindustrial residues while mitigating environmental issues. Full article

Biogenic silver nanoparticles (AgNPs) were synthesized via a green chemistry strategy using wheat extract and subsequently functionalized with a carboxymethyl chitosan–cinnamaldehyde (CMC=CIN) conjugate through covalent imine bonding. The resulting nanohybrid (AgNP–CMC=CIN) was extensively characterized to confirm successful biofunctionalization: UV–Vis spectroscopy revealed characteristic cinnamaldehyde absorption peaks; ATR-FTIR spectra confirmed polymer–terpene bonding; and TEM analysis evidenced uniform nanoparticle morphology. Dynamic light scattering (DLS) measurements indicated an increase in hydrodynamic size upon coating (from 59.46 ± 12.63 nm to 110.17 ± 4.74 nm), while maintaining low polydispersity (PDI: 0.29 to 0.27) and stable surface charge (zeta potential ~ −30 mV), suggesting colloidal stability and homogeneous polymer encapsulation. Antifungal activity was evaluated against Fusarium oxysporum, Penicillium citrinum, Aspergillus niger, and Aspergillus brasiliensis. The minimum inhibitory concentration (MIC) against F. oxysporum was significantly reduced to 83 μg/mL with AgNP–CMC=CIN, compared to 708 μg/mL for uncoated AgNPs, and was comparable to the reference fungicide tebuconazole (52 μg/mL). Seed priming with AgNP–CMC=CIN led to improved germination (85%) and markedly reduced fungal colonization, while maintaining a favorable phytotoxicity profile. These findings highlight the potential of polysaccharide-terpene-functionalized biogenic AgNPs as a sustainable alternative to conventional fungicides, supporting their application in precision agriculture and integrated crop protection strategies. Full article

Sorghum halepense (L.) Pers. (common name Johnson grass) is a perennial invasive weed that causes great harm worldwide, and its allelopathy has been demonstrated in a series of experiments. The present study offers new insights into its organ-specific phytochemical profiles using state-of-the-art metabolomic technology and explores the effects of a methanol extract of S. halepense rhizomes (ShER) and its major bioactive compounds (p-hydroxybenzoic acid and chlorogenic acid) on three noxious weed species. The phytotoxic effects of ShER are reflected through the inhibition of seed germination and reduced seedling growth, which are accompanied by changes in the antioxidant system of seedlings. Phytotoxicity is species specific and concentration dependent, and it is more pronounced against Chenopodiastrum murale (L.) S. Fuentes, Uotila & Borsch and Datura stramonium L. than highly tolerant Amaranthus retroflexus L. Catalase (CAT) is most likely the major mediator in the removal of reactive oxygen species, which are generated during germination and early seedling growth of Ch. murale exposed to ShER. The results of the present study imply the high potential of ShER in the management of amaranthaceous and solanaceous weeds, such as Ch. murale and D. stramonium, respectively. The present study offers an environmentally friendly solution for the biological control of weeds belonging to the families Amaranthaceae and Solanaceae. Also, the results of this research highlight the possibility of effective management of S. halepense by using it as a feedstock for bioherbicide production. Full article

Salvia pratensis L. is a valuable medicinal plant rich in bioactive compounds, yet its allelopathic potential remains underexplored. This study evaluated allelopathic effects and total phenolic (TPC) and flavonoid (TFC) contents of water extracts from the dry aboveground biomass of S. pratensis. To assess their selectivity and potential application in sustainable weed management, extracts at five different concentrations were tested on the germination and early growth of lettuce, radish, tomato, and carrot. The results demonstrated that the phytotoxic effects of S. pratensis extracts were both concentration- and species-dependent. Higher extract concentrations significantly inhibited germination and seedling growth, while lower concentrations of extracts stimulated shoot elongation by up to 30% compared to the control. Phytochemical analysis revealed that S. pratensis extracts contain notable TPC and TFC contents, with their concentrations increasing consistently with the extract concentration. Correlation analysis showed that higher TPC and TFC contents were strongly negatively correlated with germination and seedling growth parameters. Radish exhibited the highest sensitivity to the extracts, while lettuce was the most tolerant. Further research under field conditions is needed to assess the efficacy, selectivity, and practical potential of S. pratensis extracts in sustainable crop production systems. Full article

Biodrying and composting are aerobic processes to treat and stabilize organic solid waste, but biodrying involves a shorter process time and does not require the addition of water. The resulting biodried material (BM) is mainly used as an energy source in cement production or in municipal solid waste incineration with energy recovery, but when obtained from agricultural or agroindustrial organic waste, it could also be used as a soil amendment, such as compost (CO). In this study, the phytotoxicity of BM compared to CO, both made from organic wastes (orange peel, mulch and grass), was evaluated on seed germination and growth (for 90 days) of lettuce (Lactuca sativa L.) seedlings on treatments prepared from mixtures of BM and soil, soil (100%) and a mixture of CO and soil. The germination index (GI%) was higher for BM extracts (200 g/L) than for CO extracts (68% vs. 53%, respectively). According to their dry weight, lettuce grew more on the CO mixture (16.5 g) than on the BM (5.4–7.4 g), but both materials far exceeded the soil values (0.15 g). The absence of phytotoxicity suggests that BM acts as a soil amendment, improving soil structure and providing nutrients to the soil. Therefore, biodrying is a quick and low-cost bioprocess to obtain a soil improver. Full article

The poultry industry produces significant quantities of keratin-rich waste, primarily feathers, whose traditional disposal methods—incineration or chemical treatment—result in environmental damage and resource depletion. This research introduces a sustainable biotechnological method for the valorization of feather waste utilizing Gordonia alkanivorans S7, an actinomycete strain extracted from petroleum plant sludge. This is the inaugural publication illustrating keratinolytic activity in the Gordonia genus. The optimization of the degradation process via the Taguchi approach led to the effective biodegradation of untreated home chicken feathers, achieving dry mass loss of up to 99% after 168 h in a mineral medium. The agricultural potential of the obtained keratin hydrolysate, which was high in organic components (C 31.2%, N 8.9%, H 5.1%, and S 1.7%), was assessed. Phytotoxicity tests demonstrated that the feather hydrolysate led to better growth of the indicator plants—Sorghum saccharatum and Lepidium sativum. The highest values of root growth stimulation were 26% for S. saccharatum and 31% for L. sativum, at a dose of 0.01%. Shoot growth stimulation was noted only for L. sativum, reaching 38% (0.01%), 53% (0.05%), and 37% (0.1%), as compared to the control sample. These results demonstrate the process’s combined economic and environmental benefits, providing a fresh approach to the production of bio-based plant biostimulants and sustainable keratin waste management. Full article

This study investigated the production, purification, and evaluation of a microbial metabolite with herbicidal activity produced by Fusarium fujikuroi via submerged fermentation. The purified compound (PC) was obtained through organic solvent extraction and chromatographic purification, and assessed in bioassays using Raphanus sativus and Triticum aestivum as bioindicator plants. A concentration of 23 mg mL⁻¹ completely inhibited seed germination in 96-well plate assays, while the crude extract (EXT) and cell-free broth (CFB) allowed radicle protrusion but resulted in abnormal seedlings with chlorosis and reduced growth. Mathematical models estimated that concentrations of 16.0 mg mL⁻¹ for radish and 0.9 mg mL⁻¹ for wheat were sufficient to suppress germination with the PC. In substrate experiments, the PC at 6.4 and 64.0 mg mL⁻¹ did not inhibit germination but caused anomalies in radish and significantly reduced wheat seedling growth. In naturally infested soil, the PC maintained phytotoxicity symptoms for 21 days, and after 28 days, a concentration of 64.0 mg mL⁻¹ significantly reduced radish seedling growth. The results highlight the potential of the compound as a bioherbicide. Full article