Biometals最新文献

This study explored the eco-friendly synthesis, characterization, optimization, and biomedical potential of zinc oxide-eggshell (ZnO@ES) nanocomposites using Althaea officinalis flower extract. HPLC analysis identified pink flower extract as the highest in quercetin (88.452 ppm), making it the optimal choice for synthesis. UV–Vis spectroscopy confirmed ZnO nanostructures (384 nm peak), while characterization analyses using different spectroscopic and microscopic techniques validated their successful incorporation within the eggshell matrix. The hemocompatibility of ZnO@ES nanocomposites was assessed through hemolysis tests, which demonstrated low hemolytic activity (<5%), ensuring blood compatibility. Antimicrobial assays against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans revealed significant inhibitory effects, particularly with ZnO@ES4. Agar well diffusion tests showed that while eggshell alone lacked antimicrobial activity, ZnO@ES2 formed inhibition zones against P. aeruginosa and E. coli, whereas ZnO@ES4 was effective against P. aeruginosa, E. coli, and S. aureus. Biofilm inhibition tests further demonstrated that ZnO@ES2 and ZnO@ES4 significantly reduced E. coli and P. aeruginosa biofilms, with ZnO@ES4 being more effective. MTT cytotoxicity assays using L929 fibroblast cells confirmed biocompatibility, with ZnO@ES2 enhancing cell proliferation. By repurposing eggshell waste, this study promotes a circular economy approach, transforming an abundant biowaste into value-added biomaterials. The green synthesis method eliminates the need for toxic chemicals, ensuring an environmentally friendly and sustainable clean production process. These findings support the development of antimicrobial and biocompatible nanocomposites with biomedical applications.

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Nano-Fe forms could serve as novel fertilizers that can enhance Fe bioavailability. In this study, we synthesized magnetite nanoparticles and complexed nano-Fe₃O₄ with glycine, aspartic acid, and arginine. After synthesis, the amino acid-functionalized Fe-nanoparticles (nFe₃O₄-Gly, nFe₃O₄-Asp, and nFe₃O₄-Arg) were sprayed (75 and 150 mg L⁻¹) on okra [Abelmoschus esculentus (L.) Moench] plants, and changes in growth, biochemical traits, and their role in agronomic biofortification were investigated during a field experiment using Randomized Complete Block Design (RCBD). It was found that foliar application of these nanoparticles significantly enhanced okra biomass, and the most effective was nFe₃O₄-Gly at 75 mg/L, which enhanced shoot dry weight (+ 70.1%), number of leaves (+ 30.2%), leaf area (+ 48.3%), and number of branches (+ 55.6%) compared to the control. Moreover, foliar treatments positively influenced soluble proteins (up to 1.8 mg/g FW; + 44.4% than control) and free amino acids (up to 1.52 mg/g DW; + 57.8%). Most importantly, Fe concentrations in leaves and okra fruits substantially increased, indicating prominent Fe biofortification. After all, three harvests, okra fruits exhibited up to 0.71 mg/g DW (+ 50.7% than control). Overall, nFe₃O₄-Arg was the most effective for Fe biofortification of okra fruits at a concentration of 75 mg/L. In contrast, the yield per plant was enhanced by both nFe₃O₄-Arg and nFe₃O₄-Asp. In summary, this study demonstrated the potential of amino acid-functionalized Fe nanoparticles in improving growth and Fe bioavailability in okra, offering a promising avenue for addressing Fe deficiency in crops.

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The toxicity of chromium, in its hexavalent form (Cr(VI)), is extremely harmful to living organisms owing to its potent oxidizing properties. The present research focused in exploring the hexavalent chromium induced bioaccumulation, oxidative responses and histological anomalies in widely cultured freshwater carp Labeo rohita. Fingerlings of L. rohita were exposed to four sub-lethal waterborne concentrations of 96 h LC₅₀ (1/40th, 1/20th, 1/10th and 1/5th) of the Cr(VI). The impact of chromium was assessed in 5, 15 and 30 days exhibiting significant accumulation (P < 0.05) in the fish tissues (gill > kidney > liver > muscles) with increasing concentration. The bioaccumulation factor (BAF) also exhibited the highest in the liver tissue and least in muscle. Antioxidant enzymes like superoxidase dismutase (SOD) in the gill, liver and kidney increased significantly with the concentrations, while catalase (CAT) activity was found to fluctuate along different concentrations. Significant reduction in growth performance i.e. SGR and reduced feeding intensity was also observed after 30th day. The histopathological examination revealed epithelial hyperplasia in the gill tissues and vacuolization and shrinkage of hepatocytes in the liver tissues. Chromium toxicity-induced alterations in kidney tissues were also characterized by glomerular shrinkage and an increase in Bowman’s space. Overall, the study demonstrated that hexavalent chromium exerts significant impact on accumulation, oxidative stress, and histological anomalies, particularly at higher concentrations, in the fingerlings of L. rohita. Therefore, effective treatment of wastewater below the studied concentrations from anthropogenic sources prior to its release into aquatic environments is vital to avert pollution and safeguard the sustainability of aquatic life.

A contemporary issue arising from global industrial and economic development over the past few decades is the pollution of the environment. Chromium (Cr) is a heavy metal used in numerous industries that can build up in the surrounding ecosystem due to improper disposal techniques. Chromium pollution can cause toxicity in both the local flora and fauna. Bioremediation is perceived as an alternative to conventional treatments to mitigate chromium pollution and has thus been extensively developed in recent years. Among the various biological organisms, bacteria possesses desirable characteristics and can be cost effective while treating the pollutants. Numerous mechanisms have been evolved by bacteria to combat toxicity triggered by chromium exposure. Plant growth promoting bacteria have also evolved with mechanisms that impart resistance to susceptible plants upon chromium exposure. Large scale chromium remediation requires the use of bioreactors that can effectively utilize bacteria and nullify the toxic form of Cr. The robustness of these techniques can be increased by combining them with conventional techniques such as precipitation, filtration, etc. Case studies have also been discussed to determine their relevance in the bioremoval of Cr. The future aspects of chromium bioremediation in accordance to the omics approach has been discussed so as to understand the fate of Cr upon treatment using biological methods. This review highlights the various toxic effects that have been observed in various flora and fauna while providing insights into bacterial mechanisms that could resist Cr toxicity and their possible applications defined in terms of robustness in ex situ as well as in situ remediation technologies.

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Cadmium (Cd) has emerged as a major pollutant in agricultural soils and is known for its strong bioaccumulation potential and high toxicity even at low concentrations. Soybeans, an important grain crop in China, are particularly vulnerable to Cd contamination, which adversely affects germination and yields. Amino acids mitigate Cd toxicity and may influence Cd uptake in plants. This study aimed to evaluate the capacity of selected amino acids to mitigate Cd-induced toxicity during soybean seed germination and to investigate their effects on Cd uptake and accumulation in seedling tissues. Soybean seeds were exposed to varying Cd²⁺ concentrations (0–500 mg/L), with or without amino acid supplementation. At low Cd concentrations (0–50 mg/L), the germination rate showed a slight decline, followed by recovery. However, at 100 mg/L, germination significantly decreased, and at 500 mg/L, it decreased to 2.5%. The application of histidine, serine, tyrosine, cysteine, and methionine to seeds exposed to 500 mg/L Cd²⁺ significantly increased germination compared to untreated Cd-exposed seeds, with improvements ranging from approximately 2- to fivefold, and the highest recovery was observed in cysteine-treated seeds (up to 13.2%). Notably, the Cd content per gram of tissue was higher in amino acid-treated seedlings than in untreated controls, suggesting that amino acids may chelate Cd ions and facilitate their uptake, thereby alleviating toxicity during germination and promoting increased Cd accumulation in tissues. In conclusion, although specific amino acids can partially restore germination under high Cd stress, they may also enhance Cd accumulation in soybean seedlings.

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Coating high concentrations of copper (Cu) on the inner wall of containers prevents root entanglement by inhibiting root tip elongation. However, it remains uncertain whether roots near and far from the container wall differentially absorb Cu, thereby triggering varied defense responses. Two-year-old Camphora officinarum were planted in containers coated with 120 (T1) and 200 (T2) g L⁻¹ Cu(OH)₂ with latex as the carrier. After six months of treatment, obvious root entanglement in containers only coated with latex (T0) and control containers was observed, while no entanglement in T1 and T2. Cu(OH)₂ treatment increased soil and root Cu concentration, which exhibited significant position differences (near-wall vs. far-wall) in T1 and T2. Root Cu concentration near the container wall in T1 and T2 was 3.5 and 3.0 times higher than that far from the container wall, and 19.3 and 32.1 times higher than that in the control. Oxidative stress biomarkers increased with increasing root Cu concentration with the highest levels near the container wall in T2. Excessive Cu increased antioxidant enzyme activities and non-enzymatic antioxidant contents with higher superoxide dismutase, glutathione reductase, glutathione peroxidase, ascorbate peroxidase, ascorbate acid, and reduced glutathione in T1 and higher dehydroascorbate reductase and monodehydroascorbate in T2. Overall, antioxidant enzyme activity in roots was higher near the container wall in T1 while far from the container wall in T2. Excessive and uneven Cu distribution and oxidative stress biomarkers effectively inhibited peripheral root elongation and entanglement. During this process, although antioxidant defense responses were induced, defense capacity was impaired by supra-optimal Cu.

This study explores the biocompatibility and inhibitory effects of magnesium (Mg) and its alloy, specifically the Mg–Cu alloy, on hepatocellular carcinoma (HCC) cells. The importance of this research stems from the potential use of magnesium alloys as biomaterials in bone repair and tissue engineering, while their effects on cancer cells have not been thoroughly investigated. Existing literature shows that although the degradation properties and biocompatibility of magnesium alloys have been examined, their anticancer properties remain a topic of debate. Thus, this study aims to clarify the impact of the Mg–Cu alloy on HCC cells, providing a theoretical foundation for its use in tumor therapy. We utilized various methods, including sample preparation, cell culture, cell viability assays (CCK8), cell cycle and apoptosis analysis, and luciferase activity detection, to comprehensively evaluate the effects of magnesium and its alloys on cellular behavior. Our findings indicate that the Mg–Cu alloy significantly reduces the viability of HCC cells–Huh7 and enhances apoptosis, with a pronounced effect noted at higher extract concentrations. Additionally, the Mg–Cu alloy effectively inhibits hepatitis B virus (HBV) replication, suggesting its potential as an antiviral agent. In summary, this study highlights the promising anticancer and antiviral properties of the Mg–Cu alloy, indicating its potential applications in biomedical fields. Future research should concentrate on the clinical implications and the mechanisms that underlie these effects.

Dissolved Fe(II) influences Cd uptake and transport within wheat plants, but the specific interaction process remains elusive. This study used synchrotron radiation technology, Fourier transform infrared spectroscopy, high-performance liquid chromatography, ion chromatography, and RT-PCR to analyze the interaction processes of Fe(II) and Cd(II) ions in the roots of wheat grown in hydroponic systems containing Cd(II). The results indicated that dissolved Fe(II) decreases Cd uptake due to rhizosphere passivation, cell wall binding or blocking, and competitive absorption and regulation. Poorly crystalline Fe(III) oxides were newly formed, which facilitated the immobilization of Cd(II) on the rhizoplane (over 78%) in a hydroponic system with 5 μmol L⁻¹ Cd(II). Binding of Cd(II) by cell wall depended on pectin and phosphate contents in the presence of Fe(II). Higher accumulation of lignin in the root endodermis blocked Cd(II) transport at 1000 μmol L⁻¹ Fe(II). The Fe(II) level influenced Cd uptake by regulating the content of rhizosphere Cd(II) ions and the expression of Cd(II) uptake genes in a hydroponic system with 5 μmol L⁻¹ Cd(II). The content of CaCl₂-extractable Cd(II) was decreased by 45.4% and the expression of Cd(II) uptake genes was significantly down-regulated with Fe(II) concentration increasing from 15 to 1000 μmol L⁻¹. In the high-concentration Cd(II) (15 μmol L⁻¹) system, the inhibitory effect of dissolved Fe(II) on Cd uptake decreased due to increases in rhizosphere Cd content and expression of Cd(II) uptake genes. This work suggests that dissolved Fe(II) can reduce Cd uptake of wheat plants and provides fundamental data for food security.

The objective of this study was to examine the relationships between combined metal exposure and the comorbidities of overweight/obesity (OWOB) and myopia. Data from the National Health and Nutrition Examination Survey (2001–2006) were analyzed. The sample comprised 5927 participants aged 12 years and older, with urine measurements of 11 metals obtained through inductively coupled plasma-mass spectrometry. Least absolute shrinkage and selection operator regression models were employed to evaluate the combined effects of the metals. Multivariate logistic regression models and restricted cubic spline functions assessed the connections between metal exposure and comorbidities. The findings indicated that 1290 (21.76%) of the 5927 participants exhibited both OWOB and myopia. High levels of lead (OR = 0.76, 95% CI: 0.62–0.93), platinum (OR = 0.81, 95% CI: 0.68–0.97), and uranium (OR = 0.72, 95% CI: 0.59–0.86) were associated with a reduced risk of these comorbidities (P trend < 0.05). Conversely, elevated exposure to mixed metals was linked to an increased risk of comorbidities (OR = 1.48, 95% CI: 1.23–1.77, P trend < 0.0001). Females had a higher risk of exposure to mixed metals (OR = 4.63, 95% CI: 2.63–8.16) compared to males (OR = 1.45, 95% CI: 0.74–2.82). This study offers preliminary evidence of an association between metal exposure and the comorbidity of OWOB and myopia. Although causality cannot be inferred due to the cross-sectional nature of the study, these results support further longitudinal research.