Ion Scavenging Research Articles

Photocatalytic sequential C-H functionalization expediting acetoxymalonylation of imidazo heterocycles.

The importance of functionalized imidazo heterocycles has often been featured in several impactful research both from academia and industry. Herein, we report a direct C-3 acetoxymalonylation of imidazo heterocycles using relay C-H functionalization enabled by organophotocatalysis starring zinc acetate in the triple role of an activator, ion scavenger as well as an acetylating reagent. The mechanistic investigation revealed a sequential sp2 and sp3 C-H activation, followed by functionalization driven by zinc acetate coupled with the photocatalyst PTH. A variety of imidazo[1,2-a]pyridines and related heterocycles were explored as substrates along with several active methylene reagents, all generating the products with excellent yields and regioselectivity, thus confirming excellent functional group tolerability.

Green polyampholytic ionic scavengers as an alternative to crude oil derived chelating resins for removal of toxic metals from aqueous solutions

A group of six amino-hypophosphite polyampholytes (AHPs) was obtained and investigated for potential scavenging of four toxic metal ions – copper(II), cobalt(II), nickel(II), and lead(II). The materials were synthesised with a convenient green one-pot reaction from simple building blocks, including polyalkylenepolyamine, paraformaldehyde, and hypophosphorous acid. The AHPs are produced in a process that is greener and simpler than conventional chelating scavengers, which are mostly crude oil derived materials and difficult to dispose of in a sustainable way. The materials were characterised with FTIR spectra and tested for removal of four different toxic metal ions. It was found that all of the AHPs obtained possess ion scavenging properties in a wide pH range (2.0–8.0). Some AHPs exert a certain selectivity towards specific metal ions. The highest values of the ionic capacities derived from cation removal experiments vary in the range 0.7–2.5 mmol Me2+·g−1 of acidic AHP and 1–4 mmol Me2+·g−1 of basic AHP. These features suggest their potential application for toxic metal ion removal processes in a wide spectrum of wastewater types.

α-Amylase inhibitory potential of Thunbergia mysorensis leaves extract and bioactive compounds by in vitro and computational approach

In this study, we aim to evaluate the anti-diabetic potential of Thunbergia mysorensis leaves methanolic extract (MeL) using inhibitory assays for α-glucosidase (AG), α-amylase (AM) (carbohydrate digestive enzymes) and aldose reductase (AR) (an enzyme involved in the polyol pathway responsible for glycation). In addition to antidiabetic studies, antioxidant studies were also performed due to the fact that reactive oxygen species (ROS) are produced by various pathways under diabetic conditions. Hyperglycemia induces ROS by activating the glycation reaction and the electron transport chain in mitochondria. The MeL effectively inhibited the enzymes (AG IC50: 27.86 ± 1.0, AM IC50: 12.00 ± 0.0, AR IC50: 4.50 ± 0.09 μg/mL) and showed effective radical ion scavenging activity during the antioxidant assay (DPPH EC50: 30.10 ± 0.75, ABTS EC50: 27.25 ± 1.00, Superoxide EC50: 35.00 ± 1.50 μg/mL). Using activity-guided repeated fractionation on a silica gel column chromatography, two compounds including 3,4-dimethoxy benzoic acid (DMBA) (101 mg) and 3,4-dimethoxy cinnamic acid (DMCA) (87 mg) with potent anti-diabetic activity were extracted from the MeL of T. mysorensis leaves. Both DMBA (IC50 AG: 27.00 ± 1.05, IC50 AM: 12.15 ± 0.10, IC50 AR: 4.86 ± 0.30 μg/mL) and DMCA (IC50 AG: 27.25 ± 0.98, IC50 AM: 12.50 ± 0.20, IC50 AR: 5.00 ± 1.00 μg/mL) were subjected for enzyme inhibition. Since both compounds significantly inhibited AM, enzyme kinetics for AM inhibition was performed. The compounds also showed effective antioxidant potential (DPPH EC50: 30.50 ± 0.99, ABTS EC50: 27.86 ± 0.16, Superoxide EC50: 36.10 ± 0.24 μg/mL), and DMCA (DPPH EC50: 31.00 ± 1.00, ABTS EC50: 28.00 ± 0.25, Superoxide EC50: 36.25 ± 0.37 μg/mL). Further, to elucidate the role of DMBA and DMCA in enzyme inhibition and stability at the molecular level, both compounds were subjected for in silico enzyme inhibitory studies using molecular docking simulation, molecular dynamics (MD) simulation, and binding free energy calculations. Compared to AR and AG, AM was the most significantly inhibited enzyme (DMBA: −6.6 and DMCA: −7.8 kcal/mol), and compounds combined with AM were subjected to MD simulation. Both compounds were stable in the binding pocket of AM till 100 ns and chiefly use Van der Waal’s energy to bind. Compared to the controls, both DMBA and DMCA had a higher efficiency in the inhibition of target enzymes in vitro and in silico. The presence of DMBA and DMCA is more likely to be associated with the potential of MeL in antihyperglycemic activity. This bio-computational study indicates DMBA and DMCA as potential lead inhibitors of AM and could be used as effective anti-diabetic drugs in the near future.

Effect of superfine-grinding on the physicochemical and antioxidant properties of Dendrobium nobile powders

In herbal markets, an overwhelming majority the Dendrobium nobile are sold in dried strips form, and this product type would lead to the incomplete release of the active ingredient. To increase the bioaccessibility of Dendrobium nobile, we obtained powders of different particle sizes by shear-breaking and superfine-grinding to further compare its sensory properties, physical properties, the leaching rate of active ingredients and antioxidant activity in vitro. The results showed that the superfine-grinding changed the sensory properties and physical properties of Dendrobium nobile, with an increase in bulk density, a decrease in swelling capacity and water-holding capacity and an increase in water solubility index. The method also contributed to the release of total polysaccharides, dendrobine, total polyphenols and total flavonoids components, thereby increasing ABTS, DPPH and nitrite ion scavenging activity. In addition, scanning electron microscopy and infrared spectroscopy analyses showed that superfine-grinding had no effect on the primary structure of the fractions as with decreasing particle size. This study suggested that superfine-grinding could be a promising method for producing Dendrobium nobile powders with higher contents of bioactive compounds and bioactivity.

A YSK-Type Dehydrin from Nicotiana tabacum Enhanced Copper Tolerance in Escherichia coli

Copper is an essential micronutrient for the maintenance of normal cell function but is toxic in excess. Dehydrins are group two late embryogenesis abundant proteins, which facilitate plant survival in harsh environmental conditions. Here, a YSK-type dehydrin, NtDhn17, was cloned from Nicotiana tabacum under copper toxicity and characterized using a heterologous expression system and in vitro or in vivo experiments and exhibited characteristics of intrinsic disorder during in vitro analyses. Heterologous expression of NtDHN17 enhanced the tolerance of E. coli to various metals, osmotic, and oxidative stress. NtDHN17 showed no Cu2+-binding properties in vivo or in vitro, indicating that metal ion binding is not universal among dehydrins. In vitro and in vivo experiments suggested that NtDHN17 behaved as a potent anti-aggregation agent providing strong protection to aggregated proteins induced by excess copper ions, an effect dependent on the K-segment but not on the Y- or S-segments. In summary, the protective role of NtDHN17 towards E. coli under conditions of copper toxicity may be related to anti-aggregation ability rather than its acting as an ion scavenger, which might be a valuable target for the genetic improvement of resistance to heavy metal stresses in plants.

Rainfall characteristics significantly affect the scavenging of water-soluble ions attached to leaves

Precipitation is considered the most effective way to remove particulate matter from the leaves of plants. Changes in rainfall characteristics can affect the scavenging processes of particulate matter from leaves. In order to better understand the dynamics of PM scavenging during rainfall, especially the water-soluble ions components, leaves from the 11 plant species (trees, shrubs, terrestrial herbs, wetland plants) from the Olympic park were sampled and used in indoor experiments. During the experiments, the rainfall intensity was set at 30 mm/h, 45 mm/h, and 60 mm/h, and the duration was divided into 0–20 min, 20–40 min, and 40–60 min. The sampled plant leaves were set in the experiments at 1 m and 3 m height from the ground. Concentrations and compositions of nine water-soluble ions of rainfall samples were analyzed in this experiment. The results revealed that SO42-, Ca2+, and Na+ were the most abundant ionic species removed from the leaves, and NO3- ranked fourth, followed by Cl-, Mg2+ K+, NH4+, and F-. The ions concentration of rainfall samples decreased when the rain intensity increased from 30 to 45 mm/h and when the rain intensity increased to 60 mm/h. The efficiency of scavenging during different rainfall durations depends on the ionic species. Na+, Mg2+, Ca2+, and SO42- concentrations increased with the increase in rainfall duration, whereas those of NH4+, K+, and Cl- decreased. The effect of leaf height on ions concentration of rainfall samples was also different among the ionic species: Na+, Mg2+, Ca2+, NO3-, and F- concentrations were significantly higher at 1 m compared with 3 m. The principal component analysis of ions in rainfall samples revealed two main sources of particulate matter in our study. One is from vehicle exhaust and industrial and agricultural pollution. The other is agricultural combustion and ground dust sources. The results of the above study can provide a basis and theoretical support for the establishment of urban cleaning systems and the prevention of air pollution.

Synthesis of a New Glycoconjugate with Di-ᴅ-Psicose Anhydride Structure.

Demand for healthy diets has led researchers to explore new saccharide as sucrose alternatives. ᴅ-Psicose, the C-3 epimer of ᴅ-fructose, has a similar sweetness intensity to sucrose but contributes fewer calories. This study proposes a disaccharide with a stable structure derived from ᴅ-psicose. The compound with a spiro-tricyclic core was generated at 32% conversion via caramelization of ᴅ-psicose under acidic anhydrous conditions. The compound was identified by high-resolution mass spectrometry and multi-dimensional nuclear magnetic resonance (NMR). The molecular formula was established as C12H20O10 from the molecular weight of m/z 324.1055. Twelve signals were observed by the 13C NMR spectrum. This compound, denoted di-ᴅ-psicose anhydride (DPA), exhibited a lower water solubility (40 g/L) and higher thermal stability (peak temperature = 194.7 °C) than that of ᴅ-psicose (peak temperature = 126.5 °C). The quantitatively evaluated metal ion scavenging ability of DPA was the best in magnesium (average 98.6 ± 1.1%). This synthesis methodology can provide disaccharides with high stability-reducing heavy metals.

Flower-Shaped Carbon Nanomaterials for Highly Efficient Solar-Driven Water Evaporation.

Solar-driven interface water evaporation is an energy-saving, environmentally friendly, and efficient seawater desalination and wastewater treatment technology. However, some challenges still restrict its further industrial development, such as its complex preparation, heavy metal pollution, and insufficient energy utilization. In this study, a photothermal layer based on flower-shaped carbon nanoparticles is presented for highly efficient solar-driven interface evaporation for water treatment applications. The results show that the surface of the prepared carbon nanomaterials presents a flower-shaped structure with an excellent light absorption capacity and a large specific surface area. Moreover, the C-5.4 (Carbon-5.4) sample has an evaporation rate of 1.87 kg/m2/h and an evaporation efficiency of 87%-far higher than most photothermal materials. In addition, carbon nanomaterials have an excellent ion scavenging capacity, dye purification capacity, and outdoor practical performance. This study provides a new solution for the application of carbon nanomaterials in the field of water purification.

Aspects of thermodynamic parameters with a kinetic approach of transition metal catalysed by potassium bromate oxidation of methyl diethylene glycol (MDG) in alkaline medium

The kinetic data obtained in ruthenium(VI) catalysed oxidation of methyldiethylene glycol (MDG) in alkaline medium using potassium bromate as oxidant and transition metal ruthenium tetroxide as a homogenous catalyst. In this kinetic reaction, Hg(OAc)2 acts as a liberated bromide ion scavenger. The result shows first order with respect to KBrO3, methyldiethylene glycol (MDG) and transition metal respectively. It shows zero order dependences of the reaction on aqueous sodium hydroxide, which is used as medium of the reaction and also zero effect of mercuric acetate. In this catalysed reaction, ionic strength has positive effect. The corresponding acid was found to be main oxidation product. A plausible reaction mechanism in agreement with kinetic results was put forward.

Elite Zingiber extracts as potential free radical scavengers and radioprotectors

ABSTRACT Fresh rhizome extracts of four elite Zingiber species, viz., Zingiber kangleipakense, Zingiber montanum, Zingiber officinale, and Zingiber zerumbet, prepared in 60% aqueous ethanol/60% aqueous methanol solutions were used for assessing their comparative free radical scavenging and radioprotective properties. Various methods, such as ferric ion reducing power assay, DPPH ion scavenging assay, nitric oxide scavenging assay, metal chelating assay, thiyl/sulfur free radical reactivity assay, and hydroxyl ion scavenging assay, were employed for radical scavenging capabilities. Bio-active principles, such as total phenolic, flavonoid, and ascorbic acid contents, were also assessed. Z. officinale showed the highest TPC, TFC, and ascorbic acid content of 650 mg GAE/100 g, 889 mg QE/100 g, and 3.19 mg/100 g, respectively, as well as the greatest efficacy in ferric ion reducing and DPPH scavenging ability having lowest IC50 value of 0.22 mg/mL. Z. montanum showed the lowest IC50 value of 0.91 mg/mL in NO scavenging assay and also exhibited the highest curcumin protection in thiyl free radical scavenging assay. Z. kangleipakense showed the lowest IC50 value of 0.24 mg/mL and 0.25 mg/mL in metal ion chelating assay and hydroxyl radical assay, respectively. 60% aqueous ethanol extracts of Z. officinale and Z. kangleipakense were used for radioprotective assays both for in vitro and in vivo using plasmid pBR322 DNA and bone marrow cells of albino rats, respectively, based on their significant free radical scavenging properties. At the same concentration of 0.25 mg/mL, Z. officinale and Z. kangleipakense showed 71.50% and 56.54% protection, respectively, of DNA from exposure to 6 Gy gamma radiation. Also, Z. officinale and Z. kangleipakense exhibited 51.16% and 38.96% protection from radiation-induced chromosomal damages in rats, respectively, when exposed to 2 Gy. Reduction in the DNA open circular form as well as the chromosomal aberrations in treatments with plant extracts compared to the controls confirmed the radioprotective potentials of the extracts. The results showed that the extracts possessed potential antioxidant compounds having capacities to scavenge radiation-induced free radical species. The accessibility of the extracts in radiation countermeasures can provide immense nutraceutical potentials.

Antioxidant and Antimicrobial Activities of Green Synthesized Silver Nanoparticle Using Moringa Oleifera Seeds Extracts

Nanotechnology deals with materials in nanoscale that exhibit incredible chemical, physical and biological properties. This study is aimed at synthesizing silver nanoparticles from Moringa oleifera seed using aqueous and ethanol as solvents and compare their antioxidant as well as antimicrobial activities of these two synthesized nanoparticles. The synthesized nanoparticles were subjected to preliminary characterization using UV- spectroscopy to ensure their formation which were confirmed by attaining the plasmon resonance surface of both particles at 320nm. Standard assay for antioxidant scavenging of ferric ion and DDPH were employed and standard methods for drop plate technique, minimum inhibition concentration and minimum bactericidal/fungicidal concentrations were used. The results indicate that silver nanoparticles synthesized from ethanol extract (EEMS) has excellent ferric ion scavenging activity compared to silver nanoparticles synthesized from aqueous extract (AEMS), while AEMS has 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavenging potential compared to EEMS. Both nanoparticles show the antimicrobial efficiency were dose dependent but more inhibition zone was observed on EEMS using drop plate technique at 25mg/dl against all the organisms used (S. aureus, E. coli and C. albican). And in minimum inhibition concentrations, the result shows both particles inhibit the growth of all organisms at 6.25 µg/dl except against E. coli which is at 12.5 µg/ml by EEMS. Similarly, minimum bactericidal / fungicidal concentrations were the same in all organisms at 12.5 µg/ml except against C. albican which was at 6.25 µg/ml by EEMS. The finding revealed that both EEMS and AEMS are good antioxidants and antimicrobial agents and their activities are concentration dependent.

Comparative Insights into the Skin Beneficial Properties of Probiotic Lactobacillus Isolates of Skin Origin.

In recent times, probiotics have been emerging as one of valuable cosmetic resources. This work was undertaken to evaluate and compare the skin beneficial properties of three Lactobacillus strains, namely, L. plantarum SB202, L. fermentum SB101, and L. paraplantarum SB401, originally isolated from the healthy skins of Koreans. The Lactobacillus isolates were individually grown in MRS broth, and the corresponding cell-free conditioned mediums (CMs), LP202, LF101 and LPP401, were prepared for analyzing diverse cosmetic potentials at a comparative perspective. The superoxide radical and nitrite ion scavenging activities of the CMs were in the orders of LPP401 ≥ LF101 > LP202 and LPP401 > LF101≒LPP202, respectively. They attenuated the lipopolysaccharide-induced reactive oxygen species (ROS) and nitrite ion levels in RAW264.7 murine macrophages both in the order of LPP401 ≥ LF101 > LP202, implying their anti-inflammatory properties. They exhibited antityrosinase activities in the order of LPP401 > LF101 ≥ LP202 and diminished α-melanocyte-stimulating hormone-induced melanin levels in B16F10 melanoma cells in the order of LPP401≒LF101 > LP202, suggesting their skin whitening activities. They enhanced cornfield envelope formation in HaCaT keratinocytes in the order of LPP401 > LF101 > LP202. They inhibited the in vitro hyaluronidase and elastase activities in the orders of LPP401 > LP202 ≥ LF101 and LPP401 ≥ LP202 > LF101, respectively. Their enhancing properties on the synthesis of procollagen type I in normal human dermal fibroblasts were in the order of LF101≒LPP401 > >LP202. The CMs possess various cosmetic characteristics, such as antioxidant, skin whitening, antiaging, barrier improving, and anti-inflammatory activities. LPP401, the CM prepared from L. paraplantarum SB401, has been evaluated to be more desirable cosmetic resource than LP202 and LF101.

Copper(II) ions removal from model galvanic wastewater by green one-pot synthesised amino-hypophosphite polyampholyte

The amino-hypophosphite polyampholyte (AHP) obtained from cheap and safe building blocks lacks a typical ion-scavenger matrix derived from crude-oil intermediates like poly(divinylbenzene), which is an advantage to commercial solutions. AHP is characterised by sorption capacity comparable to some ion scavengers available on the market, as it was found that its maximum capacity in the temperature range from 298 K to 328 K varies between 114 and 146 mg Cu(II) g−1 of dry AHP. The possible application of the AHP in the Cu(II) removal process from galvanic effluent was investigated. The results show that it is possible to achieve a good removal rate for model wastewater. The inlet Cu2+ concentrations of model wastewater were 6.4 mg Cu(II) dm-3 and 36,2 mg Cu(II) dm-3, acidic and basic galvanic wastewater respectively. After the removal process concentrations were lowered to 1.3 mg Cu(II) dm-3 and 5.1 mg Cu(II) dm-3, for acidic and basic galvanic wastewater respectively. It was found that the presence of Ca(II) and Na(I) did not significantly influence the Cu(II) removal process. The obtained results indicate that the prepared more environmentally safe ion scavenger can be applicable in a wide range of metal ion removal processes.

Utilization of synthetic nano-cryptomelane for enhanced scavenging of cesium and cobalt ions from single and binary solutions

The feasibility of using nano-cryptomelane for elimination of cobalt and cesium metal ions from their single and binary solutions was studied. In this respect, the material was prepared and characterized to confirm its chemical composition and structure. Results illustrate that the synthesized nano-cryptomelane has a tunnel structure with particle size ranged between 4 and 6 nm. The material feasibility was detected by conducting a series of batch experiments for determination of the kinetic and equilibrium performance of the removal process. All characteristic Raman bands for Mn–O lattice vibrations within the (2 × 2) tunnel structure of MnO6 octahedral are observed which confirm formation of nano-cryptomelane. The specific surface area (SSA) for nano-cryptomelane was calculated and equal to 299.03 m2/g while the surface fractal information (Ds) was2.53. The process sensitivity to changes of H+ concentration is attributed to changes in structural elements-species distribution at the solid/aqueous interface. The pH optimum value was desired at pH 5 for exchange of Cs+ and/or Co2+ with K+ ions. The equilibrium studies show that Langmuir isotherm model was more fitted to the experimental data than that of Freundlich model.

Synthesis and inhibition profiles of N-benzyl- and N-allyl aniline derivatives against carbonic anhydrase and acetylcholinesterase – A molecular docking study

The alkyl and aryl derivatives of aniline are important starting materials in fine organic synthesis. Allyl bromide and benzyl chloride were taken as substrates for the alkylation reaction and as a halide ion scavenger. Triethylamine was utilized at reflux condition of N,N-dimethylacetamide (DMA). Novel synthesized N-benzyl and N-allyl aniline derivatives ( 1a-f ) were evaluated to be highly potent inhibitors for acetylcholinesterase (AChE) and carbonic anhydrases (hCAs). The half maximal inhibitory concentration (IC 50 ) of N-benzyl- and N-allyl aniline derivatives were calculated between 243.11 and 633.54 nM for hCA I, 296.32–518.37 nM for hCA II and 182.45–520.21 nM for AChE enzymes. On the other hand, K i values are in the range of 149.24 ± 15.59 to 519.59 ± 102.27 nM for AChE, 202.12 ± 16.21 to 635.31 ± 45.33 nM for hCA I and 298.57 ± 94.13 to 511.18 ± 115.98 nM for hCA II isoenzyme. Additionally, in silico molecular docking computations were performed with Autodock Vina program to support the experimental in vitro studies for both hCAs and AChE inhibitors. The in silico molecular docking results demonstrated that the scores are in good agreement with the experimental results.

Metal ion scavenging activity of elastin-like peptide analogues containing a cadmium ion binding sequence

The development of simple and safe methods for recovering environmental pollutants, such as heavy metals, is needed for sustainable environmental management. Short elastin-like peptide (ELP) analogues conjugated with metal chelating agents are considered to be useful as metal sequestering agents as they are readily produced, environment friendly, and the metal binding domain can be selected based on any target metal of interest. Due to the temperature dependent self-assembly of ELP, the peptide-based sequestering agents can be transformed from the solution state into the particles that chelate metal ions, which can then be collected as precipitates. In this study, we developed a peptide-based sequestering agent, AADAAC-(FPGVG)4, by introducing the metal-binding sequence AADAAC on the N-terminus of a short ELP, (FPGVG)4. In turbidity measurements, AADAAC-(FPGVG)4 revealed strong self-assembling ability in the presence of metal ions such as Cd2+ and Zn2+. The results from colorimetric analysis indicated that AADAAC-(FPGVG)4 could capture Cd2+ and Zn2+. Furthermore, AADAAC-(FPGVG)4 that bound to metal ions could be readily recycled by treatment with acidic solution without compromising its metal binding affinity. The present study indicates that the fusion of the metal-binding sequence and ELP is a useful and powerful strategy to develop cost-effective heavy metal scavenging agents with low environmental impacts.

The calcium-free form of atorvastatin inhibits amyloid-β(1–42) aggregation in vitro

Alzheimer's disease is characterized by the presence of extraneuronal amyloid plaques composed of amyloid-beta (Aβ) fibrillar aggregates in the brains of patients. In mouse models, it has previously been shown that atorvastatin (Ator), a cholesterol-lowering drug, has some reducing effect on the production of cerebral Aβ. A meta-analysis on humans showed moderate effects in the short term but no improvement in the Alzheimer's Disease Assessment Scale—Cognitive Subscale behavioral test. Here, we explore a potential direct effect of Ator on Aβ42 aggregation. Using NMR-based monomer consumption assays and CD spectroscopy, we observed a promoting effect of Ator in its original form (Ator-calcium) on Aβ42 aggregation, as expected because of the presence of calcium ions. The effect was reversed when applying a CaCO3-based calcium ion scavenging method, which was validated by the aforementioned methods as well as thioflavin-T fluorescence assays and transmission electron microscopy. We found that the aggregation was inhibited significantly when the concentration of calcium-free Ator exceeded that of Aβ by at least a factor of 2. The 1H–15N heteronuclear single quantum correlation and saturation-transfer difference NMR data suggest that calcium-free Ator exerts its effect through interaction with the 16KLVF19 binding site on the Aβ peptide via its aromatic rings as well as hydroxyl and methyl groups. On the other hand, molecular dynamics simulations confirmed that the increasing concentration of Ator is necessary for the inhibition of the conformational transition of Aβ from an α-helix-dominant to a β-sheet-dominant structure.

Individual and Binary Mixture Toxicity of Five Nanoparticles in Marine Microalga Heterosigma akashiwo.

The investigation of the combined toxic action of different types of nanoparticles (NPs) and their interaction between each other and with aquatic organisms is an important problem of modern ecotoxicology. In this study, we assessed the individual and mixture toxicities of cadmium and zinc sulfides (CdS and ZnS), titanium dioxide (TiO2), and two types of mesoporous silicon dioxide (with no inclusions (SMB3) and with metal inclusions (SMB24)) by a microalga growth inhibition bioassay. The counting and size measurement of microalga cells and NPs were performed by flow cytometry. The biochemical endpoints were measured by a UV-VIS microplate spectrophotometer. The highest toxicity was observed for SMB24 (EC50, 3.6 mg/L) and CdS (EC50, 21.3 mg/L). A combined toxicity bioassay demonstrated that TiO2 and the SMB3 NPs had a synergistic toxic effect in combinations with all the tested samples except SMB24, probably caused by a “Trojan horse effect”. Sample SMB24 had antagonistic toxic action with CdS and ZnS, which was probably caused by metal ion scavenging.

Janusene as a silver ion scavenger: insights from computation

The ability of Janusene to interact simultaneously with multiple silver ions.

Preparation and application of phosphorylated Lotus root polysaccharide

In this study, we extracted lotus root polysaccharide (LRP) and synthesised phosphorylated lotus root polysaccharide (PLP) using response surface methodology (RSM). RSM analyses revealed that the optimal conditions for PLP synthesis were a reaction duration of 7 h, temperature of 70 °C and pH of 11.38. Under these conditions, the predicted degree of substitution (DS%) was determined to be 9.96%. The structure of the LRP1 was examined by ultraviolet (UV) spectroscopy scan, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) (1H and 13C). The monosaccharide composition of LRP1 was determined to be mannose (0.12%), ribose(0.18%), glucuronic acid(0.60%), galacturonic acid(0.09%), glucose(98.79%) and galactose(0.21%). The number average molecular weight (Mn) and the weight average molecular weight (Mw) of LRP1 were 10236 and 251783 g/mol. LRP1 exhibited high antioxidant activities in scavenging ABTS radicals, Superoxide anion radicals and Metal ion scavenging activity. PLP exhibited strong antioxidant activity in vitro. In addition, PLP inhibited Skov3 cancer cell proliferation and induced reactive oxygen species (ROS) production. Our data revealed that PLP is a promising natural antioxidant with potential value as a food supplement and for the treatment of cancer.