Iron nanoparticles (Fe NPs) have often been used for in situ remediation of both groundwater and soil. However, the impact of Fe NPs on the distribution and transformation of As species in contaminated soil is still largely unknown. In this study, green iron oxide nanoparticles synthesized using a euphorbia cochinchinensis leaf extract (GION) were used to stabilize As in a contaminated soil. GION exhibited excellent As stabilization effects, where As in non-specifically-bound and specifically-bound fractions decreased by 27.1% and 67.3% after 120 days incubation. While both arsenate (As (V)) and arsenite (As (III)) decreased after GION application, As (V) remained the dominant species in soil. X-ray photoelectron spectroscopy (XPS) confirmed that As (V) was the dominant species in specifically-bound fractions, while As (III) was the dominant species in amorphous and poorly-crystalline hydrous oxides of Fe and Al. Correlation analysis showed that while highly available As fractions were negatively correlated to oxalate and DCB extractable Fe, they were positively correlated to Fe²⁺ content, which indicated that Fe cycling was the main process influencing changes in As availability. X-ray fluorescence (XRF) spectroscopy also showed that the Fe₂O₃ content increased by 47.9% following GION soil treatments. Overall, this work indicated that As would be transformed to more stable fractions during the cycling of Fe following GION application and that the application of GION, even in small doses, provides a low-cost and ecofriendly method for the stabilization of As in soil.

In this work, ZnO–CdWO₄ nanoparticles have been synthesized by the ecofriendly green method with lemon leaf extract to favorably anchor functional groups on their surface. The prepared ZnO–CdWO₄ nanoparticles are used as adsorbent to treat Congo red (CR) dye after characterization through FT-IR, UV–Vis, TEM, SEM-EDX, and HRTEM techniques. The equilibrium partition coefficient and adsorption capacity values for CR by ZnO–CdWO₄ are estimated as 21.4 mg g⁻¹ μM⁻¹ and 5 mg g⁻¹, respectively (at an initial dye concentration of 10 mg L⁻¹). The adsorption process is found as exothermic and spontaneous, as determined by the ΔG°, ΔS°, and ΔH° values. The Boyd plot has been used as a confirmatory tool to fit the adsorption kinetics data along with intraparticle diffusion and pseudo-second-order models. Based on this research, ZnO–CdWO₄ nanoparticles are validated as an effective adsorbent for CR dye in aqueous solutions.

As olive leaves constitute the main by-product of the olive oil industry with important environmental and economic impact, there is an increasing demand for its valorization. In the present work, we report the development and application of immobilized enzyme batch bioreactors for the chemo-enzymatic treatment of an aqueous Olea europaea leaf extract rich in oleuropein to produce an extract enriched in hydroxytyrosol and other oleuropein hydrolysis products. To this end, a robust biocatalyst was developed through the immobilization of β-glucosidase on chitosan-coated magnetic beads which exhibited high hydrolytic stability after 240 h of incubation at 37 °C. The biocatalyst was successfully used in both a rotating bed-reactor and a stir-tank reactor for the modification of the olive leaf extract leading to high conversion yields of oleuropein (exceeding 90%), while an up to 2.5 times enrichment in hydroxytyrosol was achieved. Over 20 phenolic compounds (from different classes of phytochemicals such as flavonoids, secoiridoids, and their derivatives) were identified, in the extract before and after its modification through various chromatographic and spectroscopic techniques. Finally, the biological activity of both extracts was evaluated. Compared to the non-modified extract, the modified one demonstrated 20% higher antioxidant activity, seven-fold higher antibacterial activity, and enhanced cytotoxicity against leiomyosarcoma cells.

Wound healing is one of the utmost medical issues in human and veterinary medicine, which explains the urgent need for developing new agents that possess wound healing activities. The present study aimed to assess the effectiveness of green and chemical zinc oxide nanoparticles (ZnO-NPs) for wound healing. ZnO-NPs (green using Lawsonia inermis leaf extract and chemical) were synthesized and characterized by X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, and high-resolution transmission electron microscopy (HRTEM). The gels containing the nanomaterials were prepared and inspected. Forty-five albino rats were divided into three groups, the control group was treated with normal saline 0.9%, and the other two groups were treated with gels containing green or chemical ZnO-NPs, respectively. On the 3ʳᵈ, 7ᵗʰ, 14ᵗʰ, and 21ˢᵗ days post-treatment (PT), the wounds were clinicopathologically examined. Both nanomaterials have good crystallinity and high purity, but green ZnO-NPs have a longer nanowire length and diameter than chemical ZnO-NPs. The formed gels were highly viscous with a pH of 6.5 to 7. The treated groups with ZnO-NP gels showed clinical improvement, as decreased wound surface area (WSA) percent (WSA%), increased wound contraction percent (WC%), and reduced healing time (p < 0.05) when compared with the control group. The histological scoring showed that the epithelialization score was significantly higher at the 21ˢᵗ day post-treatment in the treated groups than in the control group (p < 0.05), but the vasculature, necrosis, connective tissue formation, and collagen synthesis scores were mostly similar. The green and chemical ZnO-NP gels showed promising wound healing properties; however, the L. inermis–mediated ZnO-NPs were more effective.

In this study, the toxic effects of paraquat, one of the most commercially sold herbicides in the world, and the protective role of green tea leaf extract (GTLE) against these effects were investigated. Allium cepa L. bulbs (n = 16) were used as test material. One hundred milligrams per liter dose of paraquat and 190 and 380 mg/L doses of GTLE were preferred. Paraquat toxicity was investigated with the help of physiological (percent germination, root length, and weight gain), cytogenetic (mitotic index = MI, micronucleus = MN, and chromosomal damages = CAs), biochemical (superoxide dismutase = SOD, catalase = CAT, malondialdehyde = MDA), and anatomical (meristematic cell damages) parameters. A. cepa bulbs were divided into 6 groups as 1 control and 5 applications. The control group was germinated with tap water, and the application groups were germinated with paraquat and two different doses of GTLE. Germination was carried out at room temperature for 72 h. At the end of the period, A. cepa bulbs were prepared for physiological, cytogenetic, biochemical, and anatomical analyzes using routine preparation techniques. As a result, paraquat application caused a decrease in physiological parameters and an increase in cytogenetic (except MI) and biochemical parameters. Compared to the control (group I), the germination percentage decreased by 38%, root length 12.5 times, and weight gain 5 times decreased in group IV treated with paraquat. MDA level increased 2.58 times, SOD activity 2.48 times, and CAT activity 4.51 times increased. Paraquat application caused a decrease in the percentage of MI and an increase in the number of MN and CAs. Paraquat application caused CAs in the form of fragment, sticky chromosome, unequal distribution of chromatin, bridge, nucleus with vacuoles, nucleus bud, and reverse polarization. In the meristematic cells of the root tips applied paraquat, unclearly vascular tissue, flattened cell nucleus, epidermis, and cortex cell deformation were observed. The application of GTLE together with paraquat caused an increase in the physiological parameter values and a decrease in the cytogenetic (except MI) and biochemical parameter values. An improvement in the severity of damages induced by paraquat was also observed in root tip meristematic cells. It was determined that the improvements observed in all these parameters were related to the dose of GTLE applied. The 380 mg/L dose of GTLE provided more protection than the 190 mg/L dose. Compared to group IV in which paraquat was applied, the germination percentage increased by 21%, root length 5.83 times, and weight gain 2.92 times increased in group VI administered 380 mg/L dose of GTLE. In addition, MDA level decreased 1.78 times, SOD activity 1.59 times and CAT activity 1.65 times. In conclusion, paraquat administration at a dose of 100 mg/L caused physiological, cytogenetic, biochemical, and anatomical toxicity in A. cepa bulbs. GTLE application, on the other hand, resulted in improvements in the severity of this toxicity induced by paraquat, depending on the dose. Therefore, GTLE can be used as an effective nutritional supplement to reduce or prevent the toxicity caused by environmental agents such as pesticides.

This study demonstrates a simple protocol for phytofabrication of titanium dioxide nanoparticles (TiO₂NPs) wrapped with bioactive molecules from Ludwigia octovalvis leaf extract and their characterization by UV-visible absorption spectroscopy, Fourier transform spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectrum (XPS), and diffuse reflectance spectrum (DRS). The bandgap energy of pure green engineered TiO₂ nanoparticles was determined by DRS analysis. The XPS analysis confirmed the purity of the TiO₂ nanoparticles. Results show that the synthesized TiO₂NPs were spherical in shape with the size ranged from 36 to 81 nm. The green engineered titanium oxide nanocatalyst exhibited enhanced rate of photocatalytic degradation of important textile toxic dyes namely crystal violet (93.1%), followed by methylene blue (90.6%), methyl orange (76.7%), and alizarin red (72.4%) after 6-h exposure under sunlight irradiation. Besides, this study determines the antimicrobial efficiency of TiO₂NPs (25 μl and 50 μl), leaf extract (25 μl), and antibiotic (25 μl) against clinically isolated human pathogenic bacterial strains namely Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris, Staphylococcus epidermidis, and Escherichia coli. Results show that maximum antibacterial activity with nanotitania treatment noticed was 21.6 and 18.3-mm inhibition in case of S. epidermis and P. aeruginosa, respectively. Enhanced rate of antibiofilm activity towards S. aureus and K. pneumoniae was also observed with TiO₂NPs exposure. The biomolecule loaded TiO₂NPs exhibited the fastest bacterial deactivation dynamics towards gram-negative bacteria (E. coli), with a complete bacterial inactivation within 105-min exposure. Interestingly, anticancer activity result indicates that percentage of human cervical carcinoma cell (HeLa) viability was negatively correlated with TiO₂NPs doses used. The AO/EtBr fluorescent staining result exhibited the occurrence of more apoptosis (dead cells) of HeLa cells due to the exposure of TiO₂NPs. Altogether, the present study clearly showed that biomolecules wrapped nanotitania could be used as effective and promising compound for enhanced photocatalytic and biomedical applications in the future.

Nanotechnology tends to be a swiftly growing field of research that actively influences and inhibits the growth of bacteria/cancer. Noble metal nanoparticles (NPs) such as silver, copper, and gold have been used to damage bacterial and cancer growth over recent years; however, the toxicity of higher NPs concentrations remains a major issue. The copper oxide nanoparticles (CuONPs) were therefore fabricated using a simple green chemistry approach. Biofabricated CuONPs were characterized using UV-visible, FE-SEM with EDS, HR-TEM, FT-IR, XRD, Raman spectroscopy, and XPS analysis. Formations of CuONPs have been observed by UV-visible absorbance peak at 360.74 nm. The surface morphology of the CuONPs showed the spherical structure and size (~ 68 nm). The EDS spectrum of CuONPs has proved to be the key signals of copper (Cu) and oxygen (O) components. FT-IR analysis, to validate the important functional biomolecules (O–H, C=C, C–H, C–O) are responsible for reduction and stabilization of CuONPs. The monoclinic end-centered crystalline structures of CuONPs were confirmed with XRD planes. The electrochemical oxygen states of the CuONPs have been studied using spectroscopy of the Raman and X-ray photoelectron. After successful preparation, CuONPs examined their antibacterial, anticancer, and photocatalytic activities. Green-fabricated CuONPs were promising antibacterial candidate against human pathogenic gram-negative bacteria Escherichia coli, Vibrio cholerae, Salmonella typhimurium, Klebsiella pneumoniae, Aeromonas hydrophila, and Pseudomonas aeruginosa. CuONPs were demonstrated the excellent anticancer activity against A549 human lung adenocarcinoma cell line. Furthermore, CuONPs exhibited photocatalytic degradation of azo dyes such as eosin yellow (EY), rhodamine 123 (Rh 123), and methylene blue (MB). Biofabricated CuONPs may therefore be an important biomedical research for the aid of bacterial/cancer diseases and photocatalytic degradation of azo dyes.

Lead acetate (PbAc) is one of the toxic metals in the environment which causes many effects on different organs of the body. And due to the importance of the olive tree, with its healthy and protective elements against many diseases, the leaf extract of this tree was chosen in our study. Therefore, the aim of this study was to investigate the role of olive leaf (Olea europea L.) extract (OLE) against PbAc-induced sperm toxicity, sex hormone changes, oxidative stress, and histopathological changes in rats. Twenty male Wistar rats were divided into four groups (group 1, as control; group 2, OLE; group 3, PbAc; group 4, PbAc+OLE). In the PbAc group, the body weight, testis and epididymis weights, sexual hormones, sperm characteristics, GR, GPx, GST, GSH, SOD, and CAT were significantly decreased, and the sperm abnormality and TBARS level were significant increase when compared with control and OLE groups. Also, numerous damages to testicular tissue were observed in the PbAc group when compared to the control group, while the treatment with OLE in the fourth group led to improvement of sex hormones, semen characteristics, oxidative stress, and testicular tissue damage caused by PbAc. It can be concluded that OLE has a protective and ameliorative effects against PbAc-induced oxidative stress, apoptosis and alterations in testicular tissue, and sperm quality in rats.

Dyes and phenols are extensively used chemicals in petrochemicals, pharmaceuticals, textile, and paints industries. Due to high persistence, bioaccumulation, and toxicity, their removal from the environment is highly imperative by advanced techniques. Single metal oxide nanomaterials are generally associated with limitations of large bandgap (> 3eV) and charge recombination. Therefore, heterometallic oxides (HMOs) as CuFe₂O₄, CuMn₂O₄, and MnZn₂O₄ have been synthesized via green route by employing leaf extract of Azadirachta indica. XRD revealed the crystalline nature of HMOs nanospheres with particle size less than 100 nm. Subsequently, HMOs nanocatalysts were used as photocatalyst for removal of 3-amino phenols (3-AP) and eriochrome black T (EBT) from water under sunlight. Reaction parameters namely pollutant concentration (50–130 mgL⁻¹), catalyst dose (20–100 mg), and pH (3–11) were optimized in order to get best results. Substantial degradation (80–95%) of pollutants (50 mgL⁻¹) by HMOs (80 mg) was achieved at neutral pH under sunlight exposure. Highest removal by CuFe₂O₄ might be due to its high surface area (35.7 m²g⁻¹), low band gap (2.4 eV), larger particle stability (Zeta potential: -22.0 mV), and lower photoluminescence intensity. Sharp declines in curves were visually confirmed by color change and indicated for first-order kinetics of degradation with initial Langmuir adsorption. Spectrophotometric analysis revealed that half-life (t₁/₂) of 3-AP (0.9-1.7 h) and EBT (0.6-0.8 h) were significantly reduced. Faster degradation of EBT than 3-AP was because of less electronegative N-atom at the diazo group. Scavenger analysis indicated the presence of active radicals in photo-catalytic degradation of 3-AP and EBT. All HMOs have shown high reusability (n=8) which ensures their stability, sustainability, and efficiency. Overall, green synthesized HMOs nanoparticles with prominent surface characteristics offer a viable alternative photocatalyst for industrial applications.

In this study, we screened for the antifouling activity of 15 species plant extracts from Brazilian the Brazilian Caatinga Fabaceae against the initial colonization of natural marine bacterial biofilm. We also investigated the potential toxicity of extracts against planktonic and benthic non-target organisms. Aqueous extracts of plants collected in the Caatinga biome (PE, Brazil) were prepared and tested at different concentration levels (0, 0.5, 1, 2, 4, and 8 mg mL⁻¹). Natural marine bacterial consortium was inoculated in multi-well plates and incubated with the different treatments for 48 h. The biofilm and planktonic bacterial density and biomass inhibition were evaluated along with biofilm biomass eradication. The extracts that showed the highest bacterial biofilm inhibition were evaluated for toxicity against microalgae and crustaceans. The biofilm and planktonic bacterial inhibition potential were evaluated through flow cytometry and spectrophotometry. The selected treatments were evaluated for their toxicity using the microalgae Chaetoceros calcitrans, the copepod Nitokra sp., and the brine shrimp Artemia salina as bioindicators. Our work demonstrates the biotechnological potential of Fabaceae plant compounds as a safe antifouling alternative. Anadenanthera colubrina var. cebil fruits and Apuleia leiocarpa leaf extracts showed antibiofilm activity (≥ 80%), while Myroxylon peruiferum and Dioclea grandiflora leaf extracts showed antibiotic activity. These extracts were safe to planktonic and benthic non-target organisms. The results of this study point to potential substitutes to highly toxic antifouling paints and shed light on the prospect of a yet to be explored biome for more sustainable alternatives in biofouling research.