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This paper, for the first time, presents a potential application of titanium(IV) oxide and silicon(IV) oxide combined with lignin through a solvent-free mechanical process as admixtures for cement composites. The designed TiO 2 -SiO 2 (1:1 wt./wt.) hybrid materials mixed with lignin were extensively characterized using Fourier transform infrared spectroscopy (FTIR), electrokinetic potential analysis, thermal analysis (TGA/DTG), and porous structure properties. In addition, particle size distributions and scanning electron microscopy (SEM) were conducted to evaluate morphological and microstructural properties. In the next step, the effect of the TiO 2 -SiO 2 /lignin hybrid admixture on the workability, hydration process, microstructure, porosity, mechanical, and antimicrobial properties of the cement composites was evaluated. It was observed that appropriately designed hybrid systems based on lignin contributed to better workability, with an improvement of 25 mm, and reduced porosity of cement composites, decreasing from 14.4 % to 13.3 % in the most favorable sample. Additionally, a higher microstructure density was observed, and with increasing amounts of hybrid material admixture, the mechanical parameters also improved. In addition, the TiO 2 -SiO 2 /lignin hybrid systems had significant potential due to their high microbial purity, suggesting their effectiveness in minimizing microbial accumulation on surfaces. The final stage of analysis involved employing response surface methodology (RSM) to ascertain the optimum composition of cement composites. The results obtained indicate that the TiO 2 -SiO 2 /lignin admixtures are a promising approach for the valorization of lignin waste flows in the design of cement composites., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this study, new, functional hydroxyapatite-lignin hybrid systems were designed and characterized. The efficacy of the mechanical method utilized to obtain these systems was confirmed by Fourier transform infrared spectroscopy. The hybrid materials were also noted for their good electrokinetic stability and thermal stability. The introduction of 2.5 to 10 wt% hydroxyapatite-lignin systems into an unplasticized PVC blend using a two-step kneading and pressing method resulted in composites with relatively homogeneous distribution, as confirmed by SEM observations. The processing properties of the filler-containing blends were investigated using plastographometric analysis and MFR tests. The introduction of a lignin-predominant hybrid system into the PVC matrix results in a significant improvement of thermal stability, softening temperature, and tensile strength, while maintaining sufficient impact strength for numerous applications. Hybrid materials containing higher amounts of added lignin are promising materials with bacteriostatic properties. This can be utilized to stabilize and prevent the deposition of microorganisms, as well as the formation of biofilms, on material surfaces, thereby limiting the spread of pathogens. New eco-composites based on PVC and a hybrid filler containing lignin show promise in producing components with surfaces resistant to bacterial colonization. Hence, these materials could be used in medical and hospital equipment., Competing Interests: Declaration of competing interest The authors declare that they do not have any known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Rhamnolipids are biosurfactants produced by bacteria belonging to the Pseudomonas genus. They are discussed to complex heavy metal cations stronger than cations of Fe, Ca, Mg. It is therefore suggested to employ rhamnolipids in phytoextraction where their addition to soil should result in preferential complexation of heavy metals that can be taken up by plants, thus enabling rapid and ecological clean-up of contaminated soil. In order to test this concept, we evaluated the rhamnolipid-mediated phytoextraction of heavy metal from soil collected from the vicinity of a copper smelter. The following aspects were investigated: i) selectivity of rhamnolipids towards Cu, Zn, Pb, Cd and Fe during soil washing; ii) phytoextraction efficiency of each ion with respect to the effective concentration of rhamnolipids; iii) possible phytotoxic effects; iv) effect of micro-sized polystyrene amendment. The experiments evaluated soil washing efficiency, BCR (Community Bureau of Reference) sequential extraction to determine the impact of rhamnolipids on the mobility of metal ions, phytoextraction with maize (Zea mays L.) and phytotoxic effects based on dry matter, chlorophyll fluorescence and content. The obtained results indicated that rhamnolipids lack desired selectivity towards heavy metal ions as Fe was complexed more efficiently by 80 % of the available rhamnolipids compared to priority pollutants like Zn, Cu, Pb, which were complexed by only 20 % of the tested rhamnolipids. With increased concentration of rhamnolipids, the soil washing efficiency increased and shifted in favour of Fe, reaching values of approx. 469 mg for Fe and only 118 mg in total of all tested heavy metals. Phytoextraction also favoured the accumulation of Fe, while Cd was not removed from the soil even at the highest applied rhamnolipid concentrations. Considering the selectivity of rhamnolipids and the costs associated with their production, our results suggest the need to search for other alternative (bio)surfactants with better selectivity and lower price., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The commercial formulations of herbicides rely on surfactants which increase the efficiency of active substance. Herbicidal ionic liquids (ILs), in which cationic surfactants are combined with herbicidal anions, allow for additives' reduction and ensure very good herbicide performance with lower doses. We aimed to test the impact of synthetic and natural cations on biological degradation of 2,4-dichlorophenoxyacetic acid (2,4-D). Although primary biodegradation was high, the mineralization in agricultural soil indicated incomplete conversion of ILs to CO 2 . Even the introduction of naturally-derived cations resulted in an increase in the herbicide's half-lives - from 32 days for [Na][2,4-D] to 120 days for [Chol][2,4-D] and 300 days for the synthetic tetramethylammonium derivative [TMA][2,4-D]. Bioaugmentation with 2,4-D-degrading strains improves the herbicides' degradation, which was reflected by higher abundance of tfdA genes. Microbial community analysis confirmed that hydrophobic cationic surfactants, even those based on natural compounds, played a negative role on microbial biodiversity. Our study provides a valuable indication for further research related to the production of a new generation of environmentally friendly compounds. Moreover, the results shed a new light on the ionic liquids as independent mixtures of ions in the environment, as opposed to treating them as new type of environmental pollutants., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Lukasz Chrzanowski reports financial support was provided by National Science Centre Poland., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Despite the fact that rhamnolipids are among the most studied biosurfactants, there are still several gaps which must be filled. The aim of this review is to emphasize and to indicate which issues should be taken into account in order to achieve efficient rhamnolipids-assisted biodegradation or phytoextraction of soils contaminated by heavy metals and petroleum hydrocarbons without harmful side effects. Four main topics have been elucidated in the review: effective concentration of rhamnolipids in soil, their potential phytotoxicity, susceptibility to biodegradation and interaction with soil microorganisms. The discussed elements are often closely associated and often overlap, thus making the interpretation of research results all the more challenging. Each dedicated section of this review includes a description of potential issues and questions, an explanation of the background and rationale for each problem, analysis of relevant literature reports and a short summary with possible application guidelines. The main conclusion is that there is a necessity to establish regulations regarding effective concentrations for rhamnolipids-assisted remediation of soil. The use of an improper concentration is the direct cause of all the other discussed phenomena., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier B.V. All rights reserved.)

Modern agricultural practices are often based on the use of mixtures of specific herbicides to achieve efficient crop protection. The major drawbacks of commercial herbicidal formulations include the necessity to incorporate toxic surfactants and high volatility of active substances. Transformation of herbicides into herbicidal ionic liquids (HILs) seems to be a promising alternative which allows to almost completely reduce volatility due to ionic interactions. In the scope of this research, we transformed (2-methyl-4-chlorophenoxy)acetic acid (MCPA) into a quaternary ester (esterquat) with the use of derivatives of 2-dimethylaminoethanol. The obtained esterquats were later coupled with (±)-2-(4-chloro-2-methylphenoxy)propionic acid (MCPP) in the form of an anion. The combination of MCPA and MCPA is commonly applied in the UK, EU countries and also in the USA to increase the spectrum of targeted weed species. In the framework of this study, novel HILs with an esterquat moiety incorporating a long alkyl chain (C 8 , C 9 , C 10 , C 11 , C 12 , C 14 ) were prepared and characterized in terms of basic physicochemical properties (solubility and volatility) as well as biodegradability. Their phytotoxicity was assessed towards cornflower (Centaurea cyanus) as a model weed and maize (Zea mays) as a crop plant. The presence of the esterquat cation contributed to satisfactory solubility in water and other low polar solvents, which eliminates the need to add exogenous adjuvants. Further experiments indicated that the tested HILs stimulated the germination stage of maize and maintained high herbicidal activity towards cornflower. No significant differences in terms of properties were observed in case of HILs which included alkyl substituents with an odd number of carbon atoms. Future studies should be focused on structural modifications in order to improve the biodegradability as well as field studies for evaluation of commercial applications., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

Pyridine derivatives such as oximes and amidoximes are widely used in pharmaceutical, analytical and coordination chemistry. Increasing interest in this group of compounds as well as their complexing properties and surface activity resulted in their introduction into the environment and change of the ecosystem functioning. Based on this phenomenon, the evaluation of impact O-alkyl-pyridineamidoximes on the soil environment was determined by analysis of changes of metal mobility in soil and plant seed germination. The obtained results indicate that O-propyl-pyridineamidoximes may change the mobility of metals in soil and influence the germination and development of plants. The introduction of these compounds to soil resulted in the reduction of metal (Cu, Pb, Fe) mobility in the soil matrix. This effect resulted in the retention of metals in the soil and inhibition of their mobility. This phenomenon suggests the possibility of using the analyzed compounds in the remediation process as a stabilizing factor. Pyridineamidoximes at a concentration below 100 mg/kg of soil did not influence the seed germination and plant development., (Copyright © 2018 Elsevier B.V. All rights reserved.)