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In the present study, ethanolic extracts from the extract of unshelled seeds of Cannabis sativa L. were used to produce films in order not to generate additional waste, taking into view a circular economy. Combinations of apple pectin and citrus pectin in a ratio of 80:20 were used. Film samples containing 0.5, 1.0 and 2.5 [wt%] of the extract were extruded. Antimicrobial, mechanical and barrier properties of the obtained films were tested. Samples with 0.5 [wt%] showed a WVTR of 16.98 [g/m 2 d]. The water vapour barrier properties of the films decreased with an increase in the amount of extract used. As the amount of extract increased, the transparency of the films decreased linearly to 12.84 [%] (0.5 [wt%]), 4.90 [%] (1.0 [wt%]) and 4.99 [%] (2.5 [wt%]). It was observed that the brightness of the samples decreased with increasing concentration, due to the presence of higher levels of phenolic compounds. Tests carried out showed that the prepared films exhibited inhibitory activity against all micrograms tested. All prepared films had antibacterial activity against the Salmonella typhimurium strain. Similarly, in the case of L. monocytogenes., 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. Published by Elsevier B.V.)

In the packaging materials sector, increasing globalization has created the need for increased efforts to develop consumer protection measures. Consequently, new packaging materials are being sought to replace petroleum-based materials in the future. For this reason, global awareness of the environmental problems associated with the use of synthetic and non-degradable packaging has increased the attention paid to bio-packaging based on natural and biodegradable polymers. The bio-packaging sector is developing innovations to address the sustainability issues facing the food packaging industry. Our research has shown that green matcha extract can be a promising source of antioxidants for the production of bioactive pectin films. This study further confirmed that green matcha extract can be a promising source of antioxidants for the production of bioactive pectin films. The antioxidant activity test showed high activity of films containing matcha extract. The antioxidant activity of films without matcha addition, P, PJ, PC, PJC, was negligible. The addition of matcha to the polymer matrix did not significantly affect the mechanical properties (TS, EB) of the films obtained. The addition of cellulose had the greatest effect on changing the mechanical properties. It caused a twofold increase in the mechanical properties of the obtained packaging films. The addition of matcha significantly improved the barrier properties (for PM films, the WVTR was 3.40 [g/m 2 d]; for PJM films the WVTR was 1.70 [g/m 2 d]). The green packaging films showed no toxic effects on the plants ( Phacelia tanacetifolia, Salvia hispanica, Brassica napus ) and invertebrates ( Daphnia pulex, Chaoborus, Chironomus aprilinus ) tested. The half-solubility time of the membranes in a solution mimicking gastric acid was also determined. The longest half-dissolution time of the films was about 2 min. Our research has therefore shown that the biodegradable and environmentally safe green packaging films with antioxidant activity that we have developed can be used as edible functional casings in the future, e.g., for sausages and other food products.

In the present study, tests were carried out on composite samples on a polylactide matrix containing 25% by weight of mineral filler in the form of diatomaceous earth, base, and silanized with GPTMOS (3-glycidoxypropyltrimethoxysilane), OTES (n-octyltriethoxysilane), and MTMOS (methyltrimethoxysilane) silanes. The addition of two types of waxes, synthetic polyamide wax and natural beeswax, were used as a factor to increase the rheological properties of the composites. The obtained samples were characterized in terms of the effect of filler silanization on the degradation rate of the composites. The tests were conducted under different conditioning conditions, i.e., after exposure to strong UV radiation for 250 and 500 h, and under natural sunlight for 21 days. The conditioning carried out under natural conditions showed that the modified samples exhibit up to twice the degradation rate of pure polylactide. The addition of synthetic wax to the composites increases the tendency to agglomerate diatomaceous earth, while natural wax has a positive effect on filler dispersion. For composites modified with GPTMOS and OTES silanes, it was noted that the addition of natural wax inhibited the degree of surface degradation, compared to the addition of synthetic wax, while the addition of MTMOS silane caused the opposite effect and samples with natural wax degraded more strongly. It was shown that, despite the high degree of surface degradation, the process does not occur significantly deep into the composite and stops at a certain depth.

Chitosan is a natural and biodegradable polymer with promising potential for biomedical applications. This study concerns the production of chitosan-based materials for future use in the medical industry. Bioactive substances-caffeine and ethanolic propolis extract (EEP)-were incorporated into a chitosan matrix to increase the bioactivity of the obtained films and improve their mechanical properties. Acetic and citric acids were used as solvents in the production of the chitosan-based films. The obtained materials were characterized in terms of their antibacterial and antifungal activities, as well as their mechanical properties, including tensile strength and elongation at break. Moreover, the chemical structures and surface morphologies of the films were assessed. The results showed that the solution consisting of chitosan, citric acid, caffeine, and EEP exhibited an excellent antiradical effect. The activity of this solution (99.13%) was comparable to that of the standard antioxidant Trolox (92.82%). In addition, the film obtained from this solution showed good antibacterial activity, mainly against Escherichia coli and Enterococcus faecalis . The results also revealed that the films produced with citric acid exhibited higher activity levels against pathogenic bacteria than the films obtained with acetic acid. The antimicrobial effect of the chitosan-based films could be further enhanced by adding bioactive additives such as caffeine and propolis extract. The mechanical tests showed that the solvents and additives used affected the mechanical properties of the films obtained. The film produced from chitosan and acetic acid was characterized by the highest tensile strength value (46.95 MPa) while the chitosan-based film with citric acid showed the lowest value (2.28 MPa). The addition of caffeine and propolis to the film based on chitosan with acetic acid decreased its tensile strength while in the case of the chitosan-based film with citric acid, an increase in strength was observed. The obtained results suggested that chitosan films with natural bioactive substances can be a promising alternative to the traditional materials used in the medical industry, for example, as including biodegradable wound dressings or probiotic encapsulation materials.

In the present paper, for the first time the ability of the porous biosilica originated from three marine diatom strains of 'Nanofrustulum spp.' viz. N. wachnickianum (SZCZCH193), N. shiloi (SZCZM1342), N. cf. shiloi (SZCZP1809), to eliminate MB from aqueous solutions was investigated. The highest biomass was achieved under silicate enrichment for N. wachnickianum and N. shiloi (0.98 g L -1 DW and 0.93 g L -1 DW respectively), and under 15 °C for N. cf. shiloi (2.2 g L -1 DW). The siliceous skeletons of the strains were purified with hydrogen peroxide and characterized by SEM, EDS, the N 2 adsorption/desorption, XRD, TGA, and ATR-FTIR. The porous biosilica (20 mg DW) obtained from the strains i.e. SZCZCH193, SZCZM1342, SZCZP1809, showed efficiency in 77.6%, 96.8%, and 98.1% of 14 mg L -1  MB removal under pH 7 for 180 min, and the maximum adsorption capacity was calculated as 8.39, 19.02, and 15.17 mg g -1 , respectively. Additionally, it was possible to increase the MB removal efficiency in alkaline (pH = 11) conditions up to 99.08% for SZCZP1809 after 120 min. Modelling revealed that the adsorption of MB follows Pseudo-first order, Bangham's pore diffusion and Sips isotherm models., (© 2023. The Author(s).)

Industrial wastes with hazardous dyes serve as a major source of water pollution, which is considered to have an enormous impact on public health. In this study, an eco-friendly adsorbent, the porous siliceous frustules extracted from the diatom species Halamphora cf. salinicola , grown under laboratory conditions, has been identified. The porous architecture and negative surface charge under a pH of 7, provided by the various functional groups via Si-O, N-H, and O-H on these surfaces, revealed by SEM, the N 2 adsorption/desorption isotherm, Zeta-potential measurement, and ATR-FTIR, respectively, made the frustules an efficient mean of removal of the diazo and basic dyes from the aqueous solutions, 74.9%, 94.02%, and 99.81% against Congo Red (CR), Crystal Violet (CV), and Malachite Green (MG), respectively. The maximum adsorption capacities were calculated from isotherms, as follows: 13.04 mg g -1 , 41.97 mg g -1 , and 33.19 mg g -1 against CR, CV, and MG, respectively. Kinetic and isotherm models showed a higher correlation to Pore diffusion and Sips models for CR, and Pseudo-Second Order and Freundlich models for CV and MG. Therefore, the cleaned frustules of the thermal spring-originated diatom strain Halamphora cf. salinicola could be used as a novel adsorbent of a biological origin against anionic and basic dyes.

Amorphic diatomaceous earth is derived from natural sources, and polyamide 11 (PA11) is produced from materials of natural origin. Both of these materials show a low harmfulness to the environment and a reduced carbon footprint. This is why the combination of these two constituents is beneficial not only to improve the physicochemical and mechanical properties of polyamide 11 but also to produce a biocomposite. For the purpose of this paper, the test biocomposite was produced by combining polyamide 11, as well as basic and pre-fractionated diatomaceous earth, which had been subjected to silanization. The produced composites were used to carry out rheological (melt flow rate-MFR), mechanical (tensile strength, bending strength, impact strength), crystallographic (X-ray Diffraction-XRD), thermal and thermo-mechanical (differential scanning calorimetry-DSC, dynamic mechanical thermal analysis-DMTA) analyses, as well as a study of hydrophobic-hydrophilic properties of the material surface (wetting angle) and imaging of the surface of the composites and the fractured specimens. The tests showed that the additive 3-aminopropyltriethoxysilane (APTES) acted as an agent that improved the elasticity of composites and the melt flow rate. In addition, the produced composites showed a hydrophilic surface profile compared to pure polylactide and polyamide 11.

Recently, the development of materials based on natural polymers have been observed. This is the result of increasing environmental degradation, as well as increased awareness and consumer expectations. Many industries, especially the packaging industry, face challenges resulting from legal regulations. Chitin is the most common biopolymer right after cellulose and is used to produce chitosan. Due to the properties of chitosan, such as non-toxicity, biocompatibility, as well as antimicrobial properties, chitosan-based materials are used in many industries. Many studies have been conducted to determine the suitability of chitosan materials as food packaging, and their advantages and limitations have been identified. Thanks to the possibility of modifying the chitosan matrix by using natural additives, it is possible to strengthen the antioxidant and antimicrobial activity of chitosan films, which means that, in the near future, chitosan-based materials will be a more environmentally friendly alternative to the plastic packaging used so far. The article presents literature data on the most commonly used natural additives, such as essential oils, plant extracts, or polysaccharides, and their effects on antimicrobial, antioxidant, mechanical, barrier, and optical properties. The application of chitosan as a natural biopolymer in food packaging extends the shelf-life of various food products while simultaneously reducing the use of synthetic plastics, which in turn will have a positive impact on the natural environment. However, further research on chitosan and its combinations with various materials is still needed to extent the application of chitosan in food packaging and bring its application to industrial levels.

The biological methods are considered as environmental-eco-friendly methods for the silver nanocomposites mediation and are widely used in this context. However, the biological methods go along with the relevant limitations, for instance simultaneous synthesis of silver chlorides (AgNCl) type during the AgNPs mediation process. Therefore, the present research is coming to summarize several aspects in this context. Firstly, to present the possible promotion of the sustainable development using bioactive source (e.g. milk) as a source of two different available and new lactobacillus strains (Lactobacillus curvatus and Lactobacillus fermentum). Secondly, to show the ability of the respective isolates to be involved in mediation of various biosilver nanocomposites ((Bio)NCs) synthesis. Moreover, at this stage, for the first time, two (Bio)NCs mediation methods, called "direct method" and "modified method", have been developed, thus three types (AgNPs, AgNCl and AgNP@AgNCl) of nanocomposites mediated by two different Lactobacillus isolates take place. The interdisciplinary approach included using several spectroscopic, microscopic, spectrometric and thermogravimetric methods demonstrated that all six synthesized nanoparticles (three AgNPs, AgNCl and AgNP@AgNCl types from each source) consist of complex structure including both metallic silver core as well as organic surface deposits. The spectrometric technique allowed to identification of the organics branching surface, naturally secreted by the used Lactobacillus isolates during the inoculation step, suggesting the presence of amino-acids sequences which are direct connected with the reduction of silver ion to metal silver, and subsequently with the formation of coated (Bio)NCs and nucleation process. Moreover, based on the obtained results, the mediation mechanism of each (Bio)NCs has been proposed, suggesting that the formation of AgNPs, AgNCl and AgNP@AgNCl types occurs in different manners with faster synthesis firstly of AgNCl, then of the AgNPs type. No differences between the (Bio)NCs synthesized by two different Lactobacillus isolates have been noticed indicating no discrepancies between metabolites secreted by the respective sources., (© 2023. The Author(s).)

In this study, injection moulding was applied to produce biocomposites consisting of polylactide (PLA) and amorphous diatomaceous earth used as a filler at different concentrations. Natural wax and synthetic wax were added to improve processing properties, comparing the resulting biocomposites. The use of natural beeswax makes the composite environmentally friendly. The prepared composites contained 2.5, 5, 10 and 15% w/w filler. The test samples have been injection moulded. Rheological, mechanical, surface and other properties were assessed for the fabricated composites. The testing has shown that the use of wax additives has a significant influence on the mechanical properties (tensile strength, flexural strength, impact strength) and the hydrophilicity/hydrophobicity of composite surfaces. The addition of natural wax, especially at lower concentration, has a positive effect on the rheological properties of composites (melt flow rate, MFR), flexural modulus and impact strength. Different composite parameters are modified by different wax types so both natural and synthetic waxes, can be used interchangeably, depending on the required final material characteristics., (© 2023. The Author(s).)

In this study, for the first time, the comparison of commercially available chemical ZnO NCs and bio-ZnO NCs produced extracellularly by two different probiotic isolates (Latilactobacillus curvatus MEVP1 [OM736187] and Limosilactobacillus fermentum MEVP2 [OM736188]) were performed. All types of ZnO formulations were characterized by comprehensive interdisciplinary approach including various instrumental techniques in order to obtain nanocomposites with suitable properties for further applications, i.e. biomedical. Based on the X- ray diffraction analysis results, all tested nanoparticles exhibited the wurtzite structure with an average crystalline size distribution of 21.1 nm (CHEM_ZnO NCs), 13.2 nm (1C_ZnO NCs) and 12.9 nm (4a_ZnO NCs). The microscopy approach with use of broad range of detectors (SE, BF, HAADF) revealed the core-shell structure of bio-ZnO NCs, compared to the chemical one. The nanoparticles core of 1C and 4a_ZnO NCs are coated by the specific organic deposit coming from the metabolites produced by two probiotic strains, L. fermentum and L. curvatus. Vibrational infrared spectroscopy, photoluminescence (PL) and mass spectrometry (LDI-TOF-MS) have been used to monitor the ZnO NCs surface chemistry and allowed for better description of bio-NCs organic coating composition (amino acids residues). The characterized ZnO formulations were then assessed for their photocatalytic properties against methylene blue (MB). Both types of bio-ZnO NCs exhibited good photocatalytic activity, however, the effect of CHEM_ZnO NCs was more potent than bio-ZnO NCs. Finally, the colloidal stability of the tested nanoparticles were investigated based on the zeta potential (ZP) and hydrodynamic diameter measurements in dependence of the nanocomposites concentration and investigation time. During the biosynthesis of nano-ZnO, the increment of pH from 5.7 to around 8 were observed which suggested possible contribution of zinc aquacomplexes and carboxyl-rich compounds resulted in conversion of zinc tetrahydroxy ion complex to ZnO NCs. Overall results in present study suggest that used accessible source such us probiotic strains, L. fermentum and L. curvatus, for extracellular bio-ZnO NCs synthesis are of high interest. What is important, no significant differences between organic deposit (e.g. metabolites) produced by tested strains were noticed-both of them allowed to form the nanoparticles with natural origin coating. In comparison to chemical ZnO NCs, those synthetized via microbiological route are promising material with further biological potential once have shown high stability during 7 days., (© 2023. The Author(s).)

In the present study, tests were conducted on high-filled composite samples on a polylactide matrix, modified with diatomaceous earth, three types of silanes, and natural and synthetic wax. The obtained samples were characterized in terms of the effect of modifications on mechanical properties (tensile strength, flexural strength, and impact resistance) or processing properties, e.g., melt flow rate (MFR). The study showed that the modification had a favorable effect on the processing properties of the composites, associated with up to an eight-fold increase in flow rate index compared with the reference sample, especially for samples treated with methyltrimethoxysilane (MTMOS), and up to a ten-fold increase under low shear-rate flow conditions. The effect of the addition of waxes of different origins (synthetic and natural) was also determined, and it was shown that beeswax tended to reduce the flow rate of the composites regardless of the silane used. The addition of synthetic wax to composites increased the tendency to agglomerate diatomaceous earth, while natural wax had a positive effect on filler dispersion.

Nanostructures-assisted laser desorption/ionization mass spectrometry (NALDI-MS) is gaining attention for the analysis of a wide range of molecules. In this present investigation, Pseudostaurosira trainorii mediated biosynthesized iron-oxide nanoparticles (IONPs) have been utilized as nanostructures assisting ionization and desorption for laser desorption/ionization mass spectrometry (LDI-MS). The chain forming diatom, P. trainorii showed efficiency in the production of IONPs against 0.01 M Fe +3 (pH 2) aqueous solution at the intracellular and extracellular level. The whole biomass and external media turned dark orange in color after 3 days of reaction with Fe 3+ solution. Scanning electron microscopic (SEM) images illustrated that the surface of Fe 3+ exposed frustules of P. trainorii were entirely covered by synthesized nanostructures contrasting with the natural surface ornamentation of control cells. The IONPs loaded frustules also exhibited catalytic properties by decolorizing yellow colored nitrophenol after 3 h of reaction. Transmission electron microscopic (TEM) images confirmed that the produced particles are spindle-shaped with ~50-70 nm length and ~10-30 nm width. The biogenic IONPs were utilized as an inorganic matrix in LDI-MS and showed high sensitivity towards small molecules as glucose, alanine and triacylglycerols at nano- and picomolar level per spot, respectively. The presented biocompatible technique offers new perspectives in nanobiotechnology for the production of spindle-shaped IONPs that can be applied in future for the preparation of NALDI plates.

Amorphous diatomite was used as a filler for a thermoplastic polymer of polyamide 11 obtained from natural sources. The diatomite particles of different sizes were previously fractionated by sedimentation to obtain powders with varying particle size distribution, including powders with or without frustule particles, crushed, uncrushed or agglomerated. Biocomposites containing 2.5, 5, 10 and 20% filler were tested for their mechanical properties, including tensile strength, flexural strength and impact strength. In addition, a particle size analysis (by Dynamic Light Scattering, DLS) was performed and the dispersion of the filler in the polymer matrix (Scanning Electron Microscopy, SEM), thermal parameters (Differential Scanning Calorimetry, DSC, and Dynamic Mechanical Analysis, DMA) were determined. Testing showed that biocomposites modified with diatomaceous earth have a higher mechanical strength than the reference system, especially with larger amounts of the filler (10 and 20%), e.g., the tensile strength of pure PA11 is about 46 MPa, while 20OB and 20OF 47.5 and 47 MPa, respectively, while an increase in max. flexural strength and flexural modulus is also observed compared to pure PA11 by a maximum of 63 and 54%, respectively Diatomaceous earth can be obtained in various ways-it is commercially available or it is possible to breed diatoms in laboratory conditions, while the use of commercially available diatomite, which contains diatoms of different sizes, eliminates the possibility of controlling mechanical parameters by filling biocomposites with a filler with the desired particle size distribution, and diatom breeding is not possible on an industrial scale. Our proposed biocomposite based on fractionated diatomaceous earth using a sedimentation process addresses the current need to produce biocomposite materials from natural sources, and moreover, the nature of the process, due to its simplicity, can be successfully used on an industrial scale.

Antibiotic-resistant bacteria pose one of the major threats to human health worldwide. The issue is fundamental in the case of chronic wound treatment. One of the latest trends to overcome the problem is the search for new antibacterial agents based on silver. Thus, the aim of this research was to synthesize the silver-lactoferrin complex as a new generation of substances for the treatment of infected wounds. Moreover, one of the tasks was to investigate the formation mechanisms of the respective complexes and the influence of different synthesis conditions on the features of final product. The batch-sorption study was performed by applying the Langmuir and Freundlich isotherm models for the process description. Characterization of the complexes was carried out by spectroscopy, spectrometry, and separation techniques, as well as with electron microscopy. Additionally, the biological properties of the complex were evaluated, i.e., the antibacterial activity against selected bacteria and the impact on L929 cell-line viability. The results indicate the formation of a heterogeneous silver-lactoferrin complex that comprises silver nanoparticles. The complex has higher antibacterial strength than both native bovine lactoferrin and Ag + , while being comparable to silver toxicity.

The fractionation of diatomaceous earth (DE) using sedimentation made it possible to obtain separate unbroken diatom fractions from broken or agglomerated bodies with a range of particle sizes. The produced filler was used to prepare polylactide (PLA)/diatomaceous earth biocomposite samples containing different particle sizes, which were subjected to mechanical testing (tensile strength, flexural strength, impact strength), colloidal testing (contact angle, color change test, SEM/EDS), and thermal testing (TGA, DSC, DMA). Modification of the PLA containing the smallest particle size with diatomaceous earth (Fraction 5) resulted in a higher impact strength compared to both the pure PLA and the PLA/DE composite that contained base diatomaceous earth. Furthermore, the melt flow rate was improved by more than 80 and 60% for the composite modified with fractionated diatomaceous earth (Fraction 4) compared to pure PLA and base diatomaceous earth, respectively. The elasticity of the composite was also improved from 3.3 GPa for pure polylactide to 4.4 GPa for the system containing the smallest diatomaceous earth particles (Fraction 5).

Fabrication of flower-like nanostructures are gaining attention because of their high surface/volume ratio and extensive adsorption capacity. In the present investigation, flower-shaped, autofluorescent silver-silica (Ag-SiO 2 ) hybrid nanoparticles have been fabricated exploiting diatoms as a source of nanosilica. Two different species of Gedaniella including G. flavovirens and G. mutabilis showed their efficacy in synthesizing fluorescent Ag-SiO 2 nanoflowers (NFs) and nanospheres (NSs) against 9 mM silver nitrate solution, respectively. The biogenic nanoconjugate (Ag-SiO 2 ) was characterized by Uv-vis spectroscopy, energy dispersive X-ray spectroscopy (EDS), scanning (SEM) and transmission (TEM) electron microscopy. Production of Ag-SiO 2 hybrid nanoparticle was confirmed by observing both Ag and Si signals from a single nanoparticle in an EDS study. The broad and single absorption band at ~420 nm in Uv-vis spectroscopy confirmed proper miscibility and production of hybrid nanoparticles. The Ag-SiO 2 nanohybrids revealed autofluorescent property under the blue light region (excitation ~450-490 nm). SEM images of particles synthesized by G. flavovirens revealed the production of microscopic flower shaped Ag-SiO 2 particles with several layers of petals. A TEM study confirmed that the synthesized Ag-SiO 2 NFs are variable in size with 100-500 nm in diameter. Decolorization of methylene blue after exposure to Ag-SiO 2 particles confirmed catalytic activity of synthesized nanostructures. This eco-friendly method provides a new dimension in nanobiotechnology for biogenesis of such hierarchical nanostructure in a cost-effective way.

The aim of the research was to determine the influence of chitosan type and propolis extract concentration on biological and physicochemical properties of chitosan-propolis films in terms of their applicability in food packaging. The films were prepared using three types of chitosan: from crab shells, medium and high molecular weight and propolis concentration in the range of 0.75-5.0%. The prepared polysaccharide films were tested for antimicrobial properties, oxygen transmission rate (OTR) and water vapor transmission rate (WVTR). Moreover, sorption tests and structural analysis were carried out. Microbiological tests indicated the best antimicrobial activity for the film consisting of high molecular weight chitosan and 5.0% propolis extract. Both the type of chitosan and propolis concentration affected transmission parameters-OTR and WVTR. The best barrier properties were recorded for the film composed of high molecular weight chitosan and 5.0% propolis extract. The results of sorption experiments showed a slight influence of chitosan type and a significant effect of propolis extract concentration on equilibrium moisture content of tested films. Moreover, propolis extract concentration affected monolayer water capacity (Mm) estimated using the Guggenheim, Anderson and de Boer (GAB) sorption model. The obtained results indicate that chitosan films with an addition of propolis extract are promising materials for food packaging applications, including food containing probiotic microorganisms.

The unique properties of nanoparticles create broad opportunities as regards their application in almost all disciplines of science and technology. There are many reports about the negative influence of nanoproducts on the environment and humans. Therefore, it is of vital importance to explore the impact of metal nanoparticles on plants. This is why this work is concerned with the phytotoxic activity of ZnO nanoparticles synthesized biologically from Betonica officinalis extract against the seed of Lepidium sativum , Linum flavum , Zea mays and Salvia hispanica -Chia. The obtained ZnO nanoparticles were characterized by UV-Vis, Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM) and Atomic Force Microscopy (AFM). Those methods made it possible to assess the structure and size of the obtained ZnO nanoparticles, which was 5 nm. The obtained ZnO nanoparticles exhibited significant toxic properties throughout the range of the tested concentrations. ZnO nanoparticles were the most toxic to Lepidium sativum , for which the IC50 value was 0.0000112 [mg/ml]. The solution of Zn(NO3)2 was toxic as well, as it inhibited the growth of the tested sample throughout the range of the tested concentrations.

Diatomaceous earth are sediments of unicellular algal skeletons with a well-defined hierarchical structure. Despite many tests conducted on systems using diatomaceous earth and epoxy resins, we can find many differences in the methods of acquisition and characteristics of the composite, which may considerably affect the results. In our study, we have conducted tests to verify the impact of the method of obtaining samples and the degassing of the composite on its mechanical properties and standard deviation. The samples were cast in glass moulds and silicone moulds and then subjected to testing for their mechanical and functional properties, imaging with the use of an optical microscope and a scanning electron microscope. The tests have shown that, for samples cast in glass moulds, there is no heterogeneity within the area of the tested sample, as in the case of samples cast in silicone moulds. Silicone moulds allow for quite effective self-degassing of the resin due to the large area-to-mass ratio, and the small remaining air vesicles have a limited effect on the mechanical properties of the samples. The filler used also played a significant role. For systems containing base and rinsed diatomite, it is clear that the degassing of mixtures increases the tensile strength. For treated diatomite, the elongation at break grew along with increasing filler concentration, while for base diatomite, the improvement was observed for flexural strength and impact strength. A non-modified epoxy resin shows a tensile strength at 19.91 MPa (silicone mould cast). At the same time, the degassed, glass mould-cast systems containing 12% of base and rinsed diatoms showed a tensile strength of 27.4 MPa and 44.7 MPa, respectively. We have also observed that the higher the filler concentration, the higher were the tensile strength values, which for the rinsed diatoms reached over 55.1 MPa and for the base diatoms were maximum of 43.8 MPa. The tests, therefore, constitute a set of guidelines and recommendations for testing with the use of fillers showing an extended inner structure.

In the present investigation, fucoxanthin-one of the major pigments in diatoms-has been extracted from Nanofrustulum shiloi SZCZM1342, and its reducing efficiency in the biogenesis of gold nanoparticles (GNPs) was checked. Fucoxanthin extracted from golden-brown cells of N. shiloi was compared to the healthy, growing biomass of N. shiloi and standard fucoxanthin after separate exposure to 25 mg L -1 aqueous hydrogen tetrachloroaurate solutions at room temperature. Isolated and standard fucoxanthin were found to be able to reduce gold ions within 12 h whereas, the whole biomass turned pink in color after 72 h of reaction. The synthesized particles were characterized by UV-vis spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). UV-vis spectroscopy of purple-colored suspensions showed the absorption band at approximately 520-545 nm, indicating a strong positive signal for GNP synthesis. The SEM study revealed the deposition of GNPs on siliceous frustules of metal-treated diatom cells. The TEM analysis confirmed the GNPs synthesized by whole biomass are triangular, spherical and hexagonal in nature, whereas the particles produced by extracted and standard fucoxanthin are all spherical in nature. This study demonstrates the involvement of fucoxanthin in the reduction of gold ions and subsequent production of gold nanospheres.

The authors of this paper use an original method of diatomaceous earth fractionation, which allows for obtaining a filler with a specific particle size distribution. The method makes it possible to separate small, disintegrated and broken diatom frustules from those which maintained their original form in diatomaceous earth. The study covers a range of tests conducted to prove that such a separated diatomic fraction (3-30 µm) shows features different from the base diatomite (from 1 to above 40 µm) used as an epoxy resin filler. We have examined the mechanical properties of a series of diatomite/resin composites, considering the weight fraction of diatoms and the parameters of the composite production process. The studied composites of Epidian 601 epoxy resin cross-linked with amine-based curing agent Z-1 contained 0 to 70% vol. of diatoms or diatomaceous earth. Samples were produced by being casted into silicone molds in vacuum degassing conditions and, alternatively, without degassing. The results have shown that the size and morphology of the filler based on diatomaceous earth affects mechanical and rheological properties of systems based on epoxy resin. Elongation at rupture and flexural stress at rupture were both raised by up to 35%, and impact strength by up to 25%.

Metal combinations have been attracting the attention of scientists for some time. They usually exhibit new characteristics that are different from the ones possessed by their components. In this work, Au/ZnO/Ag nanoparticles were synthesized biologically using Glechoma hederacea L. extract. The synthesized Au/ZnO/Ag nanoparticles were characterized by UV-Vis, Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Transmission electron microscopy (TEM), and Atomic Force Microscopy (AFM). The microscopic methods confirmed the presence of spherical nanoparticles of 50-70 nm. The influence of biologically synthesized Au/ZnO/Ag nanoparticles on the vitality of human cells was evaluated in vitro with the use of established human Acute T Cell Leukemia cell line, Jurkat (ATCC® TIB-152™), as well as mononuclear cells isolated from peripheral blood (PBMC) of voluntary donors. Cell survival and the half-maximal inhibitory concentration index (IC50) were analyzed by the MTT test. The studies showed that the total loss of cell viability occurred at the Au/ZnO/Ag nanoparticle concentration range of 10 µmol-50 µmol. The use of Au/ZnO/Ag nanoparticles at the concentration of 100 µmol eliminated almost all living cells from the culture in 24h. The above observation confirms the result obtained during the MTT test.

The main objective of this work was to assess the cytotoxic activity of Au/Pt/ZnO nanoparticles synthesized using Arctium lappa extract against leukemia. The Au/Pt/ZnO nanoparticles obtained as a result of biological synthesis were characterized by UV-Vis, Scanning (SEM) and Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and Atomic Force Microscopy (AFM). The applied methods showed that the size of nanoparticles ranged from 10 to 40 nm. This work also assessed the cytotoxicity of Au/Pt/ZnO nanoparticles by means of MTT assay, and analyzed apoptosis as well as the influence of the cultivation time and concentration of Au/Pt/ZnO nanoparticles on the percentage of dead cells. The studies showed that the percentage of dead leukemia cells increased with the cultivation time and concentration of Au/Pt/ZnO nanoparticles. There was observed an increase in the percentage of cells in the G2/M phase, which suggests the stoppage of G2/M leading to cell death. The cytotoxicity of Au/Pt/ZnO nanoparticles determined by means of the MTT test indicated that the viability of leukemia cells practically disappeared when the concentration of the tested nanoparticles was 10 mol.

Due to the search for new methods for synthesizing nanomaterials, this work proposes the biological synthesis of platinum nanoparticles using Ononidis radix extract. The synthesized platinum nanoparticles were characterized by UV-Vis, Scanning Electron Microscopy (SEM) with EDS profile, Fourier transform infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). The examination conducted by means of Transmission Electron Microscopy showed the presence of spherical and hexagonal platinum nanoparticles. Atomic Force Microscopy indicated the presence of locally agglomerated nanoparticles whose size was about 4 nm. The study also examined the influence of platinum nanoparticles on human non-small cell lung carcinoma cells A549. It was found that the mortality of cells cultured together with platinum nanoparticles increased, and the proliferative activity of A549 cells decreased gradually over time in proportion to the increasing concentration of the test substance. Graphical abstract.

Due to the search for new methods of producing bimetallic nanoparticles, in this work, we have conducted a biological synthesis of Au-CuO and CuO-ZnO nanoparticles using Cnici benedicti . The synthesized Au-CuO and CuO-ZnO nanoparticles were also analyzed in terms of their antibacterial activity, as well as their influence on cell viability, using two specific cell lines: C6 rat brain glioma (ATCC® CCL-107™) and T98G human glioma (ATCC® CRL-1690™). The studies carried out by means of Atomic Force Microscopy helped to determine the presence Au-CuO nanoparticles whose size was about 13 nm. The size of CuO-ZnO nanoparticles was about 28 nm. The obtained nanoparticles showed cidal activity against glioma cells depending on the concentration of the substance and the time of culture. In the first stage, the nanoparticles limited the ability to divide cells; then, they blocked the cell cycle in the G2 - M phase, and finally led to massive cell death. The antimicrobial activity studies showed that Au-CuO nanoparticles inhibited the growth of microorganisms at lower concentrations than CuO-ZnO nanoparticles, and both kinds of nanoparticles showed excellent cidal properties.

Due to the increasing popularity of using plant extract in the synthesis of nanoparticles, this study presented the synthesis of platinum nanoparticles using Fumariae herba extract . The formation of platinum nanoparticles was confirmed by UV-visible spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and scanning electron microscopy (SEM) with EDS profile. Transmission electron micrograph presented the hexagonal and pentagonal shape of the synthesized nanoparticles sized about 30 nm. Moreover, platinum nanoparticles presented good catalytic properties in the reduction of methylene blue and crystal violet.

FT-NIR spectroscopy and color measurements were applied to evaluate the influence of packaging on cosmetic cream stored at room and refrigerated conditions. Commercial cosmetic cream was stored for 2 and 4 mo in five containers intended for cosmetics: aluminum jar with polypropylene thermos (Al/PP), acrylic jar with polypropylene thermos (Ac/PP), glass (G) jar, polypropylene (PP) jar, and styrene acrylonitrile (SAN) jars. Principal component analysis (PCA) of the FT-NIR spectra showed the effect of time on tested samples stored in all applied packagings; separate groups were formed by fresh samples and samples stored for 2 and 4 mo. The changes in samples stored in the cold for 2 mo were similar for all applied packagings as compared with fresh samples, although samples stored in SAN jars formed a separate group. After 4 mo, a separate group was formed by samples stored in G jars. For samples stored at room temperature, the influence of packaging material on cosmetic emulsion was clearly visible; four separate groups (Al/PP with PP, Ac/PP, G, and SAN) were created by samples stored for 4 mo. Using partial least squares (PLS1) regression, it was found that the FT-NIR spectra of tested samples correlated with their lightness L *, a * parameter, and total color difference Δ E * ab . FT-NIR spectroscopy is a rapid technique which could be useful to make the best choice of packaging for cosmetics protecting the original quality of products during long-term storage.

The interest in the biological synthesis of mono metal nanoparticles has been visible for years. As more attention is also given to the biological methods of synthesizing bimetallic nanoparticles, this work used the Agrimoniae herba extract in order to obtain bimetallic core-shell Cu@Pt nanoparticles. The formed core-shell Cu@Pt nanoparticles were characterized by Ultraviolet-Visible (UV-vis), Fourier Transform-Infrared (FT-IR), Scanning electron microscopy (SEM), Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM) measurements. The obtained core-shell Cu@Pt nanoparticles were analysed in terms of their antibacterial activity. It was discovered that the synthesized nanoparticles exhibited maximum activity against gram-negative bacteria E. coli ATCC 25922, S. aureus ATCC 25923, and P. aeruginosa NCTC 6749. The core-shell Cu@Pt nanoparticles also exhibited activity against the yeast C. albicans ATCC 10231 and dermatophytes T. mentagrophytes ATCC 9533.

The basic goal of this study was to synthesize zinc oxide nanoparticles using the Chelidonium majus extract and asses their cytotoxic and antimicrobial properties. The synthesized ZnO NPs were characterized by UV-Vis, Scanning Electron Microscopy (SEM) with EDS profile, Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). The aforementioned methods confirmed that the size of synthesized ZnO nanoparticles was at the range of 10 nm. The antimicrobial activity of ZnO nanoparticles synthesized using the Ch. majus extract was tested against standard strains of bacteria (Staphylococcus aureus NCTC 4163, Pseudomonas aeruginosa NCTC 6749, Escherichia coli ATCC 25922), yeast (Candida albicans ATCC 10231), filamentous fungi (molds: Aspergillus niger ATCC 16404, dermatophytes: Trichophyton rubrum ATCC 28188), clinical strains of bacteria (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus) and yeast (Candida albicans). The study showed that zinc oxide nanoparticles were excellent antimicrobial agents. What is more, biologically synthesized ZnO nanoparticles demonstrate high efficiency in treatment of human non-small cell lung cancer A549.

Nowadays green synthesis of metal nanoparticles is a developing area of research. In this study, titanium dioxide nanoparticles were biosynthesized using an aqueous solution of Echinacea purpurea herba extract as a bioreductant. This is novel and interesting method for synthesis of TiO 2 nanoparticles. The prepared titanium dioxide nanoparticles were characterized using ultraviolet-visible spectroscopy (UV-VIS), transmission electron microscopy (SEM), total reflection X-Ray fluorescence analysis (TXRF) and Fourier-transform infrared spectroscopy (FTIR) . The size of TiO 2 nanoparticles was found to be in the range of 120 nm. Moreover, the alkaline reaction of the solution (pH = 8) resulted in the increase in absorbance (280 nm), which facilitates the growth of the number of TiO 2 nanoparticles in the studied solution. Also, synthesis of TiO 2 nanoparticles using green resources like Echinacea purpurea herba is a better alternative to chemical synthesis, since this green synthesis is pollutant-free and eco-friendly.

Zinc oxide (ZnO) has broad applications in various areas. Nanoparticle synthesis using plants is an alternative to conventional physical and chemical methods. It is known that the biological synthesis of nanoparticles is gaining importance due to its simplicity, eco-friendliness and extensive antimicrobial activity. Also, in this study we report the synthesis of ZnO nanoparticles using Trifolium pratense flower extract. The prepared ZnO nanoparticles have been characterized by UV-Vis absorption spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) with Energy dispersive X-ray analysis (EDX). Besides, this study determines the antimicrobial efficacy of the synthesized ZnO nanoparticles against clinical and standard strains of S. aureus and P. aeruginosa and standard strain of E. coli.

Green synthesis of nanoparticles has gained significant importance in recent years and has become the one of the most preferred methods. Also, green synthesis of nanoparticles is valuable branch of nanotechnology. Plant extracts are eco-friendly and can be an economic option for synthesis of nanoparticles. This study presents method the synthesis of silver nanoparticles using water extract of Arnicae anthodium. Formation of silver nanoparticles was confirmed by UV-visble spectroscopy, Fourier transform infrared spectroscopy and total reflection X-ray fluorescence analysis. The morphology of the synthesized silver nanoparticles was verified by SEM-EDS. The obtained silver nanoparticles were used to study their antimicrobial activity.

This study evaluated the effectiveness of selected disinfectants against bacterial cells within a biofilm using flow cytometry, the conventional total viable count test and scanning electron microscopy (SEM). A flow cytometric procedure based on measurement of the cellular redox potential (CRP) was demonstrated to have potential for the rapid evaluation of activity against biofilm and planktonic forms of microbes. Quaternary ammonium compound-based disinfectant (QACB) demonstrated a higher level of anti-microbial activity than a performic acid preparation (PAP), with mean CRP values against P. aeruginosa cells of 2 and 1.33 relative fluorescence units (RFU) vs 63.33 and 61.33 RFU for 8 and 24 h cultures respectively. Flow cytometric evaluation of the anti-biofilm activity demonstrated a higher efficacy of QACB compared to PAP for P. aeruginosa cells of 1 and 0.66 RFU vs 18.33 and 22.66 RFU for 8 and 24 h cultures respectively. SEM images of treated P. aeruginosa cells demonstrated disinfectant-specific effects on cell morphology.