Eco-friendly modified chitosan as corrosion inhibitor for carbon steel in acidic medium: Experimental and in-depth theoretical approaches.

The industrial and medical sectors have a great interest in chitosan due to its unique properties, such as abundance, renewability, non-toxicity, antibacterial activity, biodegradability, and polyfunctionality. In this work, two modified chitosan Schiff bases (ChSB-1 and ChSB-2) were made using condensation methods, and their potential as corrosion inhibitor for carbon steel in 1 M HCl was investigated using chemical and electrochemical techniques. The ChSB-1 and ChSB-2 inhibitors exhibited remarkable inhibitory performance, as evidenced by the mass loss data, which showed 89.3 % and 91.5 % efficacy at 1 mM concentration, respectively. Because of the electron-donor substituent of methoxy (-OCH3), ChSB-2's active sites have more delocalized electrons than ChSB-1's. The PDP results showed that both ChSB-1 and ChSB-2 inhibitors have anti-corrosion characteristics because heteroatoms caused a protective layer to develop that functioned as mixed-typed inhibitors. The calculated adsorption-free energy ∆Gadso for ChSB-1 and ChSB-2, respectively, was found -36.1 and - 37.1 kJ mol-1. The ChSB-1 and ChSB-2 inhibitors adsorb on carbon steel in acidic conditions through physisorption and chemisorption interactions, and their adsorption is in line with the Langmuir adsorption model. Inhibited and uninhibited metallic surfaces were subjected to surface morphological assessments using contact angle (CA), the scanning electron microscopy and the energy dispersive X-ray (SEM/EDX) analysis. The DMol3 part of Materials Studio 7.0 software was used to perform the quantum chemical calculations based on DFT to visualize the structural features. Studies from quantum chemistry suggest the possibility of surface interaction between the unoccupied orbitals of the metal surface and the inhibitors ChSB-1, ChSB-2, ChSB-1H+, and ChSB-2H+. The results clearly show that the two inhibitors work well as environmentally friendly carbon steel corrosion inhibitors in acidic medium. This could be advantageous for industrial procedures such as pickling, cleaning, acidizing oil drilling in oil wells, and using citrus to de-sediment boilers.

Alkaloid extract of seed Citrullus colocynthis as novel green inhibitor for mild steel corrosion in one molar HCl acid solution: DFT and MC/MD approaches.

The study was designed to explore the corrosion prevention capabilities of Citrullus colocynthis seeds alkaloid-rich extract (CSEA) on MS in a 1 M HCl environment by use of electrochemical and theoretical methods. Notably, Electrochemical Impedance Spectroscopy (EIS) and potentiodynamic polarization were used to probe the impact of immersion time and temperature. Energy-dispersive X-ray spectroscopy (EDX) and spanning electron microscopy (SEM) were used to confirm the presence of a protective layer on the substrate surface. Density functional theory (DFT) method was used to optimize the investigated species by use of B3LYP/6-31 + G(d, p) level of theory. The global and local quantum chemical reactivity descriptors were calculated to explore the inhibition corrosion efficiency and to identify the most favorable sites for electrophilic and nucleophilic attacks. Monte Carlo (MC) and molecular dynamics simulation (MDS) methods were used to study the interactions between corrosion inhibitor and metal surface. Noteworthy, results showed that CSEA exhibited an impressive inhibition efficiency, which reached 94.3% with a concentration of 2 g/L at 298 K. Potentiodynamic polarization revealed that the extract acted as a mixed-type inhibitor. Nyquist graphs showed that charge-transfer resistance and dæouble-layer capacitance both rised with increasing CSEA concentration, suggesting better inhibition efficiency. Notably, the Langmuir adsorption isotherm is well-aligned with the adsorption of inhibitor compounds. Importantly, all aforementioned theoretical methods were in agreement with the experimental findings. The outcome of the present work supported using Citrullus colocynthis seeds alkaloid-rich extract as ecofriendly agents to prevent corrosion.

Dataset on acido-biocatalysis of agro solid wastes in acidic medium for the conversion of pink solo Carica papaya seed oil to biodiesel fuel.

In an attempt to find a single stage conversion of high free fatty acid (FFA) of Pink Solo Carica papaya oilseed rather than the double steps, acidic catalyst was derived from burnt fermented sweet corn stock powder immersed in acidic environment, and was used to convert Pink Solo Carica papaya oilseed to biodiesel. The derived catalyst was characterized using TGA, ZETA, FTIR, SEM-EDX, XRF-FS, and BET analysis. Process modeling and optimization was carried out using response surface methodology (RSM) and artificial neural network (ANN). The produced biodiesel was quantified by determining its physicochemical parameters, and the strength of acidified catalyst (AC) was tested in reusability cycles. Dataset show the extracted oil is acidic (acid value >3.0 mg KOH/g oil). The produced AC showed the presence of Quartz (68%), Orthoclase (7.1%), ibise (9.8%), and illite (15%). Process modeling and optimization validated the optimum biodiesel yield of 99.02% (wt./wt.) at X1 = 78.42 (min), X2 = 2.19 (%wt.), and X3 = 5.969 for RSMBBD, and 99.97% (wt./wt.) at X1 = 70.41 (min), X2 = 5.40 (%wt.), and X3 = 6.00 for ANNFA. Catalyst recyclability test data undergoes 10 recycles, and the produced biodiesel qualities were in line with the recommended standard. The study concluded that the burnt sweet corn stock powder, when immersed in acid, can convert high FFA oil of Pink Solo Carica papaya to biodiesel in a single stage.

Origanum Grosii Extracts as Novel Eco-Friendly Corrosion Inhibitors for Mild Steel In HCl Medium.

Two green inhibitors extracted from an endemic species (Origanum grosii (Og)) using two solvents of different polarity (water and ethanol), OgW (aqueous extract) and OgE (ethanolic extract), were used for the anticorrosion of mild steel (M steel) in a 1 M HCl medium. Anticorrosive performance of OgW and OgE was assessed using standard electrochemical techniques, EIS/PDP measurements, weight loss method and SEM/EDX surface analysis. The results show that OgW achieves a maximum inhibition efficiency of 92 % and that the extract in aqueous medium (more polar) is more efficient than the extract in ethanolic medium (less polar). Both extracts act as mixed inhibitors and their corrosion process is predominantly governed by a charge transfer. Concentration and temperature effect was studied and shown that they are two antagonistic parameters for the evolution of inhibitory effectiveness of both OgW and OgE. The adsorption isotherms of the two inhibitors OgE and OgW obey to the Langmuir adsorption model. Moreover, the examination of SEM images and EDX spectra support a deposit of both extracts on the metal surface by an adsorption phenomenon. Besides, theoretical approach of the molecular structures of the major compounds M-OgW and M-OgE and inhibition efficiency was examined via DFT calculations and molecular dynamics simulations and it was consistent with the experimental findings.

Microplastic pollution in high-altitude Nainital lake, Uttarakhand, India.

Microplastics (MPs) contamination has been reported in all environmental compartments, but very limited information is available at higher-altitude lakes. Nainital Lake, located at a high altitude in the Indian Himalayas, has various ecosystem services and is the major source of water for Nainital town, but the MP abundance is still unknown. This study presents the first evidence of the abundance and distribution of MP in Nainital Lake. Surface water and sediment samples were analysed from 16 different sites in and around the catchment area of Nainital Lake. The MP were observed in all the samples, and their abundance in surface water was 8.6-56.0 particles L-1 in the lake and 2.4-88.0 particles L-1 in hotspot sites. In the surface sediment, MP abundance ranged from 0.4-10.6 particles g-1, while in the hotspot sediment, the mean abundance was 0.6 ± 0.5 particles g-1. Fibers were the dominant MP, while 0.02-1 mm were the predominant size of MP particles. The results of chemical characterization showed the presence of six polymers, among which high-density polyethylene was the most abundant. The Polymer Hazard Index assessment classified the identified polymers as low-to high-risk categories, with a higher abundance of low- (polypropylene) and medium- (polyethylene)-risk polymers. Tourist activities and run-off catchments can be considered the major sources of MP, which can affect the ecosystem. Minimal concentrations of MP were observed in the tube well and drinking water, which depicts the direct risks to humans and, thus, the need for remedial measures to prevent MP contamination in drinking water. This study improves the knowledge of MP contamination in the higher-altitude freshwater lake, which can be the major pathway for the transport of MP to the rivers, and also emphasizes the need for waste management in Nainital town.

Efficacy of different remineralizing agents on primary teeth exposed to therapeutic gamma radiation: An in vitro randomized control study.

Background: Therapeutic radiation-induced caries is a major side effect. Dental and oral heath are adversely affected by the direct effects of radiotherapy. Preventive procedures are preferred to reinforce dental tissue resistance against radiation damage. Objective: Research aim is to test the impact of different remineralizing protocols on the mineral content of deciduous enamel exposed to a therapeutic dose of gamma radiation. Methods: Thirty deciduous enamel specimens were divided randomly into three experimental categories based on the type of remineralizing agent used. Group I (gamma irradiated teeth, then painted with fluoride varnish), Group II (gamma irradiated teeth, then treated with bioactive glass) and Group III (gamma irradiated teeth, and then treated with a diode laser 980 nm). Prepared specimens were assessed for mineral content by environmental Energy Dispersive X-ray Analysis. SEM photomicrographs were performed simultaneously. Results were investigated concerning pre- and post-irradiation values difference. The paired-samples t-test was performed to compare the atomic and weight percentages of the selected elements obtained from the samples in the control groups before and after therapeutic radiation. One-way analysis of variance and post hoc Tukey tests were used to compare between the categories regarding weight and atomic percentages. Results: Calcium/Phosphorus (Ca/P) ratio and Fluoride content decreased significantly after radiotherapy. Fluoride content significantly increased after remineralizing agents' application with the greatest increase in Bioactive glass group followed by fluoride varnish (F.varnish) group and the least increase was in diode laser group. Significant increase in Ca/P ratio in bioactive glass group followed by insignificant increase in F.varnish group (I) with the least increase noticed in the Diode laser group. Conclusion: Therapeutic radiation caused marked decrease in enamel mineral content. However, the reminralizing agents applied have an improving effect on the caused damage.

Landfill leachate from Municipal Solid Waste: Multi-technique approach for its fine characterization and determination of the thermodynamic and sequestering properties towards some toxic metals.

Landfill leachate is a multicomponent aqueous matrix generated by the percolation of rainwater into the body of a landfill. Considering its content of natural and xenobiotic components, it must be considered as a waste, whose composition depends on type of waste, biodegradation processes, rainwater, composition and compaction of waste and their age; these factors influence the transport, absorption, toxicity, bioaccumulation of the contaminants. Leachates sampled from landfill and downhill piezometers, in periods characterized by different rainfall, were studied by ATR-FTIR and SEM-EDX techniques; analyses were carried out on dried and calcinated residues obtained at T = 383 and 923 K, respectively. The chemical-physical characterization of all the leachates was carried out by using the official methods of analysis, obtaining for many metals and some organic contaminants exceedance of the concentrations with respect to the limits established by the Italian Legislative Decree 152/2006. From potentiometric titrations carried out at T = 298.15 K in NaCl(aq) and applying the Polyprotic Like model, each leachate resulted to have a different composition in terms of COOH and OH groups and various acid-base properties. The interacting ability of leachates with metal cations (Cd2+, Zn2+, Cu2+) was studied by potentiometric and voltammetric (only for Pb2+) techniques in NaCl (NaNO3 for Pb2+) aqueous solutions, at I = 0.15 mol dm-3 and T = 298.15 K, obtaining diverse speciation models and complexes of very different stability. The leachates sequestering ability towards the metal cations was quantified at various pH values using the pL0.5 parameter, proving that each leachate has a different strength of interaction towards the metals, that tends to increase with the pH and confirming that they behave as carriers of contaminants through the soil and towards groundwater, with the consequent problems of contamination and/or environmental disaster and risks for the human health.

Twin-screw extrusion of vitamin D3/iron-blend granules in corn and lentil composite flours: Stability, microstructure, and interaction of vitamin D3 with human osteoblast cells.

Vitamin D3 (VD3) and iron-blend granules were blended with corn and lentil composite flour (75/25, w/w) and fed into a pilot-scale twin-screw extruder to produce ready-to-eat snacks. The morphology and microstructure of extruded snacks were examined using scanning electron microscopy with energy-dispersive X-ray (SEM-EDX), X-ray powder diffraction, and FT-IR. Differential scanning calorimetry and thermogravimetric analysis measured the melting temperature and thermal stability of the extrudates. SEM and FT-IR analysis demonstrate that micronutrients are mixed well in formulations used in extrudates at high shear and high temperatures. The SEM-EDX exhibited the presence of iron, whereas high performance liquid chromatography measurements confirmed the significant retention of VD3 in the extruded snacks. The interaction between VD3 and human osteoblast cells was studied using live imaging and the MMT assay. Overall, for the first time, VD3 and Fe2+ blend granules have been used in an extrusion platform, which has significant potential for the intervention of VD3 and iron deficiencies. PRACTICAL APPLICATION: For the first time, we reported the use of VD3/iron-blend granules in extruded products. The findings of this work demonstrated the thermal stability and capability of providing adequate quantities of VD3 and iron in corn flour/lentil flour/VD3-iron blend extruded snacks. Furthermore, the interaction of VD3 with osteoblast cells highlights the potential health benefits of the extrudates.

Characterization of microplastics in digestive tract of commercial fish species from the Oman Sea.

Microplastics (MPs) content of the digestive tract of two commercial fish from the northern shores of the Oman Sea were investigated. The MPs were characterized by optical microscopy, fluorescent microscopy, and SEM-EDX for their number, shape, size, and color. Polymer composition was analyzes using micro-Raman spectroscopy (RMS). MPs were recovered in all fish samples (100 %), with an average of 43.16 ± 8.23 items/individual in Otolithes ruber, and 29.9 ± 2.73 items/individual in Acanthopagrus latus. The predominant shape of MPs in both fishes was fiber (46 %) with black, transparent, and white colors. The majority of MPs were <1000 µm (75 %), and half of the MPs were smaller than 300 µm in size. Their synthetic nature was confirmed by Nile Red staining and determination of the elemental composition of selected items. Polypropylene (PP) and polyethylene (PE) were the dominant plastic polymers in the fish digestive tracts. This study reveals abundance distribution of MPs in digestive tract of commercial marine fish. High number of ingested MPs can alarm the accumulation of MPs in the northern of Oman Sea ecosystem with anthropogenic activities and raises issues in public health.

Respirable silica particles in coal mine dust: An image library dataset collected using scanning electron microscopy with energy dispersive X-ray spectroscopy.

This dataset comprises an image library of 282 respirable silica particles. The particles were identified in samples of respirable coal mine dust (RCMD) collected in numerous US underground mines, and samples of lab-generated respirable dust that were created using the primary dust source materials (e.g., raw coal and rock) obtained from those mines. (A limited number of particles were also identified in samples generated from silica-containing reference materials.) Silica particle identification was done by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), and then each particle was imaged and analyzed at both low (5 kV) and high (20 kV) accelerating voltage. SEM micrographs were captured at high magnification (i.e., 5000-20,000 ×) and overlaid with elemental maps to visually indicate relative Si and Al content; spectra were also collected to determine Si and Al % in each particle. This dataset can inform the understanding of real respirable silica particles in coal mine environments, which may differ from idealized (i.e., pure, independent) silica particles. The dataset therefore provides valuable context for the design and interpretation of research related to: respirable silica exposure studies, sample analysis and monitoring techniques, or dust control.

Poultices as biofilms of titanium dioxide nanoparticles/carboxymethyl cellulose/Phytagel for cleaning of infected cotton paper by Aspergillus sydowii and Nevskia terrae.

In this study, TiO2 nanoparticle (TiO2NP)-coated film was produced to protect manuscripts against microorganisms using ecofriendly benign materials. As a result, a simple method was created that uses poultice biofilm made of carboxymethyl cellulose (CMC) and Phytagel plant cell (PGP) loaded with TiO2NPs to preserve manuscripts against microbes in an environmentally responsible way. Three volumes (1, 2, 4 mL) of TiO2NPs were put into a biofilm combination to produce the poultices known as CMC/PGP/TiO2-1, CMC/PGP/TiO2-2, and CMC/PGP/TiO2-3. The synthesized TiO2NPs were nearly spherical in shape, small in size (98 nm), and stable (zeta potential value - 33 mV). The results showed that the unique deposition of TiO2NPs on the biofilm surface gave the produced films loaded with TiO2NPs a rough structure. The highest values of mechanical characteristics were determined to be in CMC/PGP/TiO2-1 with values of 25.4 g, 6.6 MPa, and 11.4%, for tensile strength, elongation at break, and tear strength, respectively. Based on molecular identification, the fungus Aspergillus sydowii and the bacterium Nevskia terrae, with accession numbers MG991624 and AB806800, respectively, were isolated and identified from an antiquated manuscript formed from cellulosic fibers. Before the experiments, the produced cotton paper samples were aged, and then, one group was infected for 6 months by A. sydowii and the second group with N. terrae. Following the preparation of a CMC/PGP biofilm loaded with various volumes of TiO2NPs, poultices were applied to infected cotton paper in order to clean it. The infected cotton paper was placed inside the sandwich-like poultices that were created. The poultice CMC/PGP/TiO2-2 demonstrated potential for preventing the growth of A. sydowii and N. terrae-infected cotton paper, when the fibers were saved, cleaned, and coated with CMC/PGP/TiO2-2 after absorbing the fungus and the bacterium and exhibiting exceptional antimicrobial activities. Finally, the novel biofilms have demonstrated their capacity to lessen microbial contamination of cotton paper. In order to generalize the usage of these poultices, it is also advised that they be produced on a large scale and tested on a variety of organic materials in the future.

Physico-chemical characterization of indoor settled dust in Children's microenvironments in Ikeja and Ota, Nigeria.

Indoor dust is a collection of particles identified as a major reservoir for several emerging indoor chemical pollutants. This study presents indoor dust particles' morphology and elemental composition in eight children's urban and semi-urban microenvironments (A-H) in Nigeria. Samples were collected using a Tesco vacuum cleaner and analyzed with scanning electron microscopy coupled with an energy-dispersive X-ray (SEM-EDX). The morphology results confirm the presence of alumino silicates, mineral particles and flakes, fly ash and soot, and soot aggregates deposited on alumino silicate particles in the sampled microenvironments. These particles may trigger serious health concerns that directly or indirectly affect the overall well-being of children. From the EDX analysis, the trend of elements (w/w %) in the dust particles across the sampled sites was silicon (386) > oxygen (174)> aluminium (114) > carbon (34.5) > iron (28.0) > calcium (16.7) > magnesium (14.2) > sodium (7.92) > potassium (7.58) > phosphorus (2.22) > lead (2.04) > manganese (1.17) > titanium (0.21). Lead (Pb), a toxic and carcinogenic heavy metal, was observed in locations A and B. This is a concern without a safe lead level because of the neurotoxicity effect on children. As a result, further research on the concentrations, bioavailability, and health risk assessment of heavy metals in these sampled locations is recommended. Furthermore, frequent vacuum cleaning, wet moping and adequate ventilation systems will significantly reduce the accumulation of indoor dust-bound metals.

Phytoremediation potential of Solanum viarum Dunal and functional aspects of their capitate glandular trichomes in lead, cadmium, and zinc detoxification.

In the present scenario, remediation of heavy metals (HMs) contaminated soil has become an important work to be done for the well-being of human and their environment. Phytoremediation can be regarded as an excellent method in environmental technologies. The present contemporary research explores the Solanum viarum Dunal function as a potential accumulator of hazardous HMs viz. lead (Pb), cadmium (Cd), zinc (Zn), and their combination (CHM). On toxic concentrations of Pb, Cd, Zn, and their synergistic exposure, seeds had better germination percentage and their 90d old aerial tissues accumulated Pb, Cd, and Zn concentrations ranging from 44.53, 84.06, and 147.29 mg kg-1 DW, respectively. Pattern of accumulation in roots was as Zn 70.08 > Pb 48.55 > Cd 42.21 mg kg-1DW. Under HMs treatment, positive modulation in physiological performances, antioxidant activities suggested an enhanced tolerance along with higher membrane stability due to increased levels of lignin, proline, and sugar. Phenotypic variations were recorded in prickles and roots of 120 d old HM stressed plants, which are directly correlated with better acclimation. Interestingly, trichomes of the plant also showed HM accumulation. Later, SEM-EDX microanalysis suggested involvement of S. viarum capitate glandular trichomes as excretory organs for Cd and Zn. Thus, the present study provides an understanding of the mechanism that makes S. viarum to function as potent accumulator and provides information to generate plants to be used for phytoremediation.

Comparative evaluation of cadmium phytoremediation potential of five varieties of Helianthus annuus L.

Helianthus annuus is a potential metal accumulator plant, which can find application in cadmium (Cd) phytoremediation and provide economic gains in terms of oil yield. This study is focused on Cd accumulation analysis, physiological and biochemical responses of five varieties of H. annuus (DRSF-108, DRSF-113, LSFH-171, Phule Bhaskar and KBSH-44). Plantlets of all varieties were treated with various Cd concentrations (10, 50, 100, 300 and 500 mg kg-1) for 20, 40 and 60 days. DRSF-108 showed the maximum total Cd accumulation (430.52 mg kg-1) in whole plant while minimum accumulation was observed in KBSH-44 (150.66 mg kg-1) at 500 mg kg-1 Cd after 60 days. The highest level of proline and polyphenol in DRSF-108 were 27.206 µmol g-1 fw and 6.86 mg g-1 fw, respectively. Antioxidant enzymes (catalase, ascorbate peroxidase and glutathione reductase) also showed increased activity in response to Cd treatment. SEM-EDX analysis of potential accumulator genotype, DRSF-108, showed the distribution of intracellular Cd into plant tissues. Therefore, it is concluded that among five varieties, DRSF-108 was the most potential Cd accumulator and had a higher capacity for Cd tolerance compared to other varieties. Our findings may allow us to extend variety DRSF-108 for sustainable farming and Cd remediation.

Phytoremediation of environmental contaminants is a promising strategy, however, the success depends on the use of suitable plants. Helianthus annuus is a good phytoremediator plant and the use of most promising genotype is desirable. This work evaluated five genotypes of H. annuus for cadmium accumulation and identified the best variety, DRSF-108 that can be used for cadmium remediation. The work shall pave way for field application of sunflower plants in cadmium remediation.

Study on Flexural Behaviour of Ferrocement Composites Reinforced with Polypropylene Warp Knitted Fabric.

Ferrocement is a cost-effective construction material used in the low-cost constructions. It is produced with the combination of cement mortar with closely spaced wire mesh known as chicken wire mesh. Ferrocement process eliminates coarse aggregates when compared to reinforced concrete thus makes the process simple. This paper deals with the influence of various characteristics of warp knitted fabric on the flexural properties of ferrocement composites. Ferrocement composites have a wide range of applications in the construction industry and it has some limitations due to the durability issues. Among the various durability issues, corrosion is one of the main issues to be addressed to enhance the long-term service life of the ferrocement composites. The idea of using non-metallic mesh to eliminate the corrosion problem is discussed in this paper. In this experiment, warp knitted fabric reinforced ferrocement composites were produced using polypropylene warp knitted fabrics. This paper deals with the flexural properties of ferrocement composites made of warp knitted fabric coated with expoxy. This paper deals with the flexural properties of ferrocement composites made of warp knitted fabric coated with expoxy. These composites were analyzed for their flexural strength, energy absorption and ductile property. The variables in the experiment are filament thickness, warp knitted structure and number of layers in the composites. Experimental results proved that the replacement of chicken mesh wire by warp knitted fabrics has an impact in the flexural properties of the composites and the effect of variables in the experiment set up has been analyzed. There is an imporvement of 200% is observed in the first crack load and 120% improvement in the ultimate load of the warp knit fabric reinforced composite compared to control sample. Experimental results proved that there is an increase in flexural strength of ferrocement composites made up with warp knitted fabrics. Microstructure studies like SEM and EDX on ferrocement laminates confirmed good bonding between the mortar mix and warp knitted fabrics.

Antioxidant and Anti-Urolithiatic Activity of Aqueous and Ethanolic Extracts from Saussurea costus (Falc) Lispich Using Scanning Electron Microscopy.

The plant Saussurea costus (Falc) Lipsch has many biological activities and a strong curative and preventive power against a variety of diseases including cancer, diabetes, and hemorrhoids. In the current study, phytochemical screening was carried out as well as an investigation of the antilithiatic and antioxidant activities of aqueous and ethanolic extracts of this plant. The results showed that aqueous and ethanolic extracts were effective in reducing cystine stone mass and that the aqueous extract of Saussurea costus (Falc) Lipsch had the highest percentage of dissolution (6.756 ± 1.024) (p < 0.05). A turbidimetric method and a crystallization test were used to evaluate the antilithiatic activity of an aqueous and ethanolic extract of this plant on calcium oxalate crystallization. The results of these methods revealed that the ethanolic extract of this plant has a significant inhibitory effect on calcium oxalate crystallization, with a percentage inhibition of (91.017 ± 0.299) (p < 0.05) for a concentration of 2 mg mL−1. The DPPH method revealed that the ethanolic extract of Saussurea costus (Falc) Lipsch with a concentration of (IC50 = 0.12325 mg mL−1) had the highest IC50, whereas the FRAP method revealed that the aqueous extract of Saussurea costus (Falc) Lipsch with a concentration of 300 µg mL−1 has the most significant reducing power with (OD = 0.56 ± 0.05). These findings indicate that aqueous and ethanolic extracts of Saussurea costus (Falc) Lipsch had a significant effect on whewellite and weddellite and a greater free radical scavenging effect but had no effect on cystine dissolution.

White rot fungus mediated removal of mercury from wastewater.

Heavy metal contamination creates numerous problems in environment and considered as big challenge for the society. Mercury (Hg) may exert several harmful effects on human heath including nervous system, digestive system, and immune system, along with damage in lungs and kidneys, which might be fatal. In this study, the removal of Hg from the wastewater by using a whiter rot fungus Phlebia floridensis was evaluated in a batch culture system for 7 days. The fungus was also evaluated for the tolerance level of Hg and the morphological changes were studied by SEM-EDX. The fungus could tolerate up to 100 µM of Hg concentration. Scanning electron microscopic images showed changes in the morphology and fine structures of the fungal hyphae. Atomic absorption spectroscopic analyses of the treated water sample revealed that the fungus could remove 70%-84% of Hg depending upon the initial concentration. The pH fluctuation was recorded from 5.8 to 6.8 during the experimental conditions at temperature 28°C ± 2°C. Thus, the study explores the use of this fungus for the application in metal containing wastewater treatment. PRACTITIONER POINTS: Hg contaminated water can be treated by using white rot fungus, Phlebia floridensis. The fungus may accumulate mercury inside as well as on the surface of fungal mycelial biomass. Change in hyphal morphology was observed in the presence of lower concentration of the metal.

Occurrence, distribution and sources of microplastics in beach sediments of Miri coast, NW Borneo.

Microplastics (MPs) pollution has gained a lot of global interests due to its toxicity to the surrounding ecosystems. The aim of this study is to identify the abundances, physical characteristics, polymer type and elemental composition of MPs in beach sediments of Miri coast, located in Sarawak State, East Malaysia. A total of 1553 particles from 24 sediment samples, collected from eight different beaches along Miri coastline were identified. MPs from the sediments were extracted using density separation method and analyzed through stereoscopic microscope, ATR-FTIR and SEM-EDX. MPs were present most abundant in Lutong Beach, which is the hotspot for the recreational activities. Fragments were identified as the highest abundance type of MPs, followed by fiber, foam and pellet. MPs of size of <1 mm were predominantly present in the samples. Varieties of colors were distinguished in which transparent or no color MPs were the highest quantity studied in the samples. Polymers identified were mainly polyethylene (PE), polyester (PET), polystyrene (PS) and polypropylene (PP), derived from primary and secondary MPs. Carbon and oxygen were dominant and have the highest concentration identified with other elements such as Ca, Al, Ti and Cl. The primary use of these elements as additives are associated with the manufacturing process as they are used to enhance the quality during plastic production. The outcome of this study is to be the first report to identify and characterize the MPs in beach sediments of Miri coast. The occurrence of MPs in Miri beaches may negatively impact marine organisms as this affects their food chain. As consumers, humans are most likely to be affected by the presence of MPs due to their consumption of marine animals, particularly fish present in this region.

The ion partition detected in homeopathically manufactured medicine cuprum metallicum and controls

Homeopathy is highly controversial. The main reason for this is its use of very highly dilute medicines (high homeopathic potencies, HHP), diluted beyond the Avogadro/Loschmidt limit. Research using Nano Tracking Analysis has demonstrated the presence of particles in HHPs. This study aims to verify the results of a previous publication that identified the ionic composition of these particles in all dilutions. We used Scanning Electron Microscopy & Energy Dispersive X-Ray Spectroscopy (SEM-EDX) to examine dilutions of a commonly used homeopathic medicine, an insoluble metal, Cuprum metallicum, for the presence of particles (NPs). The homeopathic medicines tested were specially prepared according to the European pharmacopoeia standards. We compared the homeopathic dilutions/dynamizations of copper with simple dilutions and dynamized lactose controls. We observed an ionic diversity common to all preparations including HHPs but also significant differences in the relative quantity of each ion between manufacturing lines of homeopathic copper and lactose controls. The probability that the observed differences could have occurred chance alone (especially above Avogadro limit) can be rejected at p < 0.001. The essential component of these homeopathic medicines is sodium hydrogen carbonate, modulated by some other elements and by its quantity, size and shape. Homeopathic medicines made of Cuprum metallicum do contain material with a specific ionic composition even in HHPs diluted beyond the Avogadro/Loschmidt limit. This specificity can be attributed to the manufacturing process. This material demonstrates that the step-by-step process (dynamized or not) does not match the theoretical expectations of a dilution process. The starting material and dilution/dynamization method influences the nature of these NPs. Further measurements are needed on other raw materials using the same controls (solvent and simply diluted manufacturing lines) to support these findings. The role of sodium bicarbonate must be carefully studied in the future.

Evaluation of the changes in physical properties and mineral content of enamel exposed to radiation after treating with remineralization agent.

OBJECTIVE: The aim of this study was to investigate the effect of different remineralization agents on the physical properties and elemental content of enamel exposed to radiation. MATERIAL AND METHOD: The enamel surfaces of impacted third molar teeth were prepared, and six study groups were created (n = 6). Next, 60 Gy radiation was applied to each group. Between applications, each group except for the control group was treated with a different remineralization agent (sodium fluoride, casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), casein phosphopeptide amorphous calcium phosphate with fluorite (CPP-ACFP), bioactive glass, or chitosan). The results were evaluated in terms of pre- and post-radiation values and the difference between the two. The paired-samples t test and analysis of variance test were used in the analysis of normally distributed hardness and roughness values, while Wilcoxon's signed ranks test, and the Kruskal Wallis and Mann-Whitney U tests were used in the analysis of elemental content without normal distribution. RESULTS: A statistically significant decrease was observed in microhardness measurements in all groups. Intragroup evaluation revealed a statistically significant difference between the NaF and bioactive glass groups (p < 0.05). No significant difference was observed between the groups' roughness measurements (p < 0.05). Intergroup evaluation of surface roughness revealed a significant difference in the CPP-ACFP and chitosan groups (p < 0.05). Pre- and post-radiation oxygen, magnesium, and potassium levels and Ca/P ratios also differed significantly (p < 0.05). CONCLUSION: Radiation caused a statistically significant difference in the microhardness and elemental content of enamel. However, no significant difference was observed in enamel roughness. The applied remineralizing agents have a partial ameliorating effect on the adverse impacts of radiation. CLINICAL RELEVANCE: Radiation causes changes in the mechanical properties and elemental content of tooth enamel. Remineralizing agent application is a promising option in reducing the adverse effects of irradiation.