Improving therapeutic potential in breast cancer via histone deacetylase inhibitor loaded nanofibrils

Epigenetic modifications play a significant role in cancer progression, making them potential targets for therapy. Histone deacetylase inhibitors have shown promise in inhibiting cancer cell growth, including in breast cancer (BC). In this research, we examined the potential of using suberoyl anilide hydroxamic acid (SAHA)-loaded β-lg nanofibrils as a drug delivery system for triple-negative BC cell lines. We assessed their impact on cell cycle progression, apoptosis, levels of reactive oxygen species, and mitochondrial membrane potential in cancer cells. The combination of SAHA and β-lg nanofibrils demonstrated enhanced efficacy in inhibiting cell growth, inducing cell cycle arrest, and promoting apoptosis (43.78%) compared to SAHA alone (40.09%). Moreover, it effectively targeted cancer cells without promoting drug resistance while using a low concentration of the nanofibrils. These findings underscore the promising potential of nanofibril-based drug delivery systems for BC treatment.

Utilizing protein nanofibrils as a scaffold for enhancing nutritional value in toned milk

Toned milk is a lower-fat, healthier alternative to whole milk that still contains all essential nutrients. A number of methods have been developed to improve the functionality of toned milk and make it more appealing to the consumers. However, these methods often involve extensive processing techniques and can be expensive. Therefore, alternative methods are needed. Proteins are well known for their ability to form well-defined nanofibril materials that can be used as a scaffold for various applications. In this article, a straightforward self-assembly process was used to load inulin into protein nanofibrils, creating unique composite nanofibrils. Characterization using AFM and SEM revealed well-defined composite nanofibrils with an average diameter of 4-6 nm and lengths ranging from 0.25 μm up to 10 μm. FT-IR and in-vitro release assays show that inulin was successfully attached to prepared protein nanofibrils. The composite nanofibrils were tested on toned milk to enhance the physico/chemical properties and nutritional values. The findings can be applied to the food industry to create a number of novel functional food products cost-effectively.

Preparation and Characterization of Magnetite-Polyvinyl Alcohol Hybrid Nanoparticles (As-PVA-MNPs) Using Acanthophora spicifera Marine Algae Extract for Enhanced Antimicrobial Activity Against Pathogenic Microorganisms

The present study focused on preparing and characterizing magnetite-polyvinyl alcohol (PVA) hybrid nanoparticles using Acanthophora spicifera marine algae extract as a reducing agent. Various analytical techniques, including UV-Visible spectrometry, Fourier-transform infrared (FTIR) analysis, energy-dispersive X-ray (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis, were used to characterize the nanoparticles. The results showed the successful synthesis of nanoparticles with a characteristic color change and absorption peak at 400 nm in UV-Visible spectrometry. FTIR analysis indicated an interaction between the carboxyl group and magnetite-polyvinyl alcohol hybrid ions. SEM analysis revealed spherical nanoparticles with sizes ranging from 20 to 100 nm. EDX analysis confirmed the presence of strong magnetite peaks in Acanthophora spicifera, validating successful preparation. XRD analysis indicated the crystalline nature of the nanoparticles. Furthermore, the antimicrobial potential of As-PVA-MNPs was evaluated, demonstrating a significant zone of inhibition against tested bacterial and fungal samples at a concentration of 100 µg. These findings suggest the promising antimicrobial activity of the synthesized nanoparticles for potential applications in combating pathogenic microorganisms.

The inchoate horizon of electrolyzer designs, membranes and catalysts towards highly efficient electrochemical reduction of CO2 to formic acid

This review explores the recent advances in CO2 reactor configurations, components, membranes and electrocatalysts for HCOOH generation and draw readers attention to construct the economic, scalable and energy efficient CO2R electrolyzers.

Polypyrrole/zeolite composite - A nanoadsorbent for reactive dyes removal from synthetic solution

Synthetic dyes are among the common pollutants in the ecosystem. In the present study, polypyrrole/zeolite (PPy/Ze) nanocomposite was prepared and subsequently assessed for the removal of Reactive blue (RB) and Reactive red (RR) from synthetic solution. The polymeric PPy/Ze composite was synthesized by chemical oxidation of pyrrole in the presence of zeolite. Electron microscopic images (transmission and scanning) indicate that PPy/Ze nanocomposite was spherical in shape with an average size of 40-80 nm. The characteristic pyrrole and zeolite Fourier transform infrared spectrum peaks (1542 cm^-1, 1463 cm^-1, 1156 cm^-1, 1054 cm^-1, 879 cm^-1 and 756 cm^-1) in the nanocomposite confirmed zeolite integration with polypyrrole. Experimental variables such as PPy/Ze nanocomposite dose, initial RB and RR concentration, reaction temperature and pH were optimized. The PPy/Ze nanocomposite adsorbed 86.2% of RB and 88.3% of RR from synthetic solution at optimal conditions (pH 9, initial RR or RB concentration, 75 mg/l; PPy/Ze dose, 1.8 g/l; and temperature, 50 °C). Freundlich isotherm model and pseudo-second-order kinetics showed better fit for both RB and RR removal from synthetic solution. X-ray diffractogram confirmed the amorphous nature of PPy/Ze nanocomposite and that it was not altered even after dye adsorption. Adsorption-desorption studies showed that the composite has satisfactory adsorption potential for four cycles. The results show that the PPy/Ze nanocomposite could be used for the removal of dyes from wastewaters.

The Synthesis, Characterization and Applications of Polyhydroxyalkanoates (PHAs) and PHA-Based Nanoparticles

Polyhydroxyalkanoates (PHAs) are storage granules found in bacteria that are essentially hydroxy fatty acid polyesters. PHA molecules appear in variety of structures, and amongst all types of PHAs, polyhydroxybutyrate (PHB) is used in versatile fields as it is a biodegradable, biocompatible, and ecologically safe thermoplastic. The unique physicochemical characteristics of these PHAs have made them applicable in nanotechnology, tissue engineering, and other biomedical applications. In this review, the optimization, extraction, and characterization of PHAs are described. Their production and application in nanotechnology are also portrayed in this review, and the precise and various production methods of PHA-based nanoparticles, such as emulsion solvent diffusion, nanoprecipitation, and dialysis are discussed. The characterization techniques such as UV-Vis, FTIR, SEM, Zeta Potential, and XRD are also elaborated.

Significance of conducting polyaniline based composites for the removal of dyes and heavy metals from aqueous solution and wastewaters - A review

Dyes and heavy metals pollution have become a major environmental concern worldwide. Various methods, such as advanced oxidation, biodegradation, precipitation, flocculation, ultra filtration, ion-exchange, electro-chemical degradation and coagulation, have been proposed for the removal of dyes and heavy metals from contaminated wastewater. Of these methods, adsorption and detoxification are considered as the most promising and economically viable. Polyaniline-based composites, a material prepared by combining polyaniline with one or more similar or disimilar materials, have been reported as good adsorbents to remove and detoxify different groups of pollutants due to their unique physical and chemical properties. In the last decade, several studies have reported the effective adsorption (∼95%) of dyes and heavy metals onto polyaniline based composites. Furthermore, some polyaniline -composites reduced the adsorbed heavy metals into less toxic state. This review compiles the application of different polyaniline composites for adsorption and/or detoxifcation of dyes and heavy metals and documents composite preparation methods, morphology and properties of the composites, and mechanism of dyes and heavy metals adsorption. Based on the avilabile literature, this review suggests that more studies are warranted to understand the influence of various conditions and experimental variables on dyes and heavy metals removal from wastewater and/or aqueous solution.

Comparative bioefficacy of Bacillus and Pseudomonas chitinase against Helopeltis theivora in tea (Camellia sinensis (L.) O.Kuntze

Tea (Camellia sinensis (L.) O.Kuntze) is an industry-oriented economical crop in India. Among the sap sucking pests, tea mosquito bug (Helopeltis theivora) is one of the most serious pests causing heavy crop loss in tea plantation. Continuous use of chemical pesticides causes environmental pollution and health hazards besides developing pesticide residues in tea powder. The control of pests by bacterial metabolite is an alternative that may contribute to reduce or eliminate the chemical pesticide use. The use of chitinase as a biological control is an emerging field of research. In the present study, Chitinase (~ 25 kDa) was purified from Bacillus cereus C-13 strain using gel-filtration chromatography and further characterized for its optimum pH, temperature and substrate specificity. Bioefficacy of chitinase from B. cereus C-13 was compared with our previously reported Pseudomonas fluorescens MP-13 chitinase against H. theivora. Result concluded that, 100% and 78% mortality was observed by using P. fluorescens MP-13 chitinase and B. cereus C-13 chitinase, respectively. In future, bacterial chitinase can be utilized in eco-friendly pest management strategies.

Preparation and characterization of hybrid chitosan-silver nanoparticles (Chi-Ag NPs); A potential antibacterial agent

In this study, a novel ecofriendly chitosan- silver nanoparticles hybrid was developed. Biological method using leaf extract of T. portulacifolium was used as reducing agent for its synthesis and the antibacterial efficiency of these hybrid nanoparticles were evaluated against the bacteria E. coli and S. marcescens organisms. The intense peak observed around 419 nm in the UV-Vis indicates the formation of silver nanoparticles. The XRD analysis showed that the hybrid chitosan-silver nanoparticles have a polycrystalline and face-centered cubic configuration. FTIR spectrum hybrid chitosan-silver nanoparticles indicated speaks vibration of NH and OH. The EDS analysis confirmed the presence of Ag, O, C and N elements in the prepared sample. The spherical shape was obtained from TEM analysis and it indicated that with average particles around 3.24 nm to 44.80 nm. The prepared hybrid chitosan-silver nanoparticles showed significant antibacterial activities against E. coli and S. marcescens. In addition, the surface membrane damages and surface morphology of test pathogens were visualized using FESEM analysis.

dz2 orbital-mediated bound magnetic polarons in ferromagnetic Ce-doped BaTiO3 nanoparticles and their enriched two-photon absorption cross-section

The enriched ferromagnetism and two-photon absorption (TPA) cross-section of perovskite BaTiO3 nanoparticles are indispensable for magnetic and optical data storage applications. In this work, hydrothermally synthesized Ce-doped BaTiO3 nanoparticles exhibited the maximum room temperature ferromagnetism (4.26 × 10-3 emu g-1) at 4 mol% due to the increase in oxygen vacancies, as evidenced by X-ray photoelectron and electron spin resonance spectroscopy and density functional theory (DFT) calculations. Hence, the oxygen vacancy-constituted bound magnetic polaron (BMP) model was invoked to explain the enhancement in ferromagnetism. The BMP theoretical model indicated an increase in BMP magnetization (M0, 3.0 to 4.8 × 10-3 emu g-1) and true spontaneous moment per BMP (meff, 4 to 9.88 × 10-4 emu) upon Ce doping. DFT calculations showed that BMPs mediate via the Ti dz2 orbitals, leading to ferromagnetism. Besides, it is known that the magnetic moment induced by Ce at the Ba site is higher than Ce at the Ti site in the presence of oxygen vacancies. The open aperture Z-scan technique displayed the highest TPA coefficient, β (7.08 × 10-10 m W-1), and TPA cross-section, σTPA (455 × 104 GM), at 4 mol% of Ce as a result of the robust TPA-induced excited state absorption. The large σTPA is attributed to the longer excited state lifetime, τ (7.63 ns), of the charge carriers created by oxygen vacancies and Ce ions, which encounter several electronic transitions in the excited sub-states.

Molecular subtypes as a predictor of response to neoadjuvant chemotherapy in breast cancer patients

PURPOSE

The objective of this study was to assess response to neoadjuvant chemotherapy in molecular subtypes of breast cancer.

METHODS

This study included 60 patients with locally advanced and metastatic breast cancer. The authors excluded patients who already underwent mastectomy or were given any chemotherapy/radiotherapy. They analyzed the clinical and immunohistochemical characteristics using core biopsy specimens to determine their correlations with response to chemotherapy.

RESULTS

A clinical complete response was observed in 19 patients (31.7%), a clinical partial response in 30 patients (50%), clinical stable disease in 8 patients (13.3%), and progressive disease in 3 patients (5%). A pathologic complete response (pCR) was observed in 7 (21.87%) of 32 patients who underwent surgery. High Ki-67 was associated with human epidermal growth factor receptor 2 (HER2)-positive status (P = 0.027) and triple-negative breast cancer (TNBC) (P = 0.006). Multiple logistic regression analysis showed that pCR was correlated with HER2 status (odds ratio 26.589, confidence interval [CI] =1.606-44.190), P = 0.022. Of the seven patients found to have pCR, six patients (85.7%) were treated with taxol-containing regimen. The other parameters that were correlated with pCR are TNBC and estrogen receptor/progesterone receptor status. Tumor size, Ki-67 value, and grade of the tumor were not correlated with clinical response.

CONCLUSION

Molecular subtype in breast cancer is an effective factor for predicting response to neoadjuvant chemotherapy. HER2-positive status was associated with high Ki-67 and high clinical and pathological response rate. Taxol needs to be added in neoadjuvant chemotherapy to improve pCR. Luminal subtypes respond poorly to chemotherapy.

Surface active gold nanoparticles biosynthesis by new approach for bionanocatalytic activity

In the present day, nanotechnology is one of the most promising leading scientific and potentials areas in modern key technology development toward to the humankind. The synthesis of noble metal nanoparticles (NPs) is an expanding research area due to the possible applications for the development of bio-medical applications. Eco-friendly approach for the biosynthesis of gold nanoparticles (AuNPs) using the aqueous extract from Ruellia tuberosa and Phyllanthus acidus (leaf and twig) for the first time. Surface active AuNPs were characterized by UV-Vis spectroscopy, FTIR (Fourier transform infrared) spectroscopy, DSC (differential scanning colorimetry), DLS (dynamic light scattering) and environmental SEM (scanning electron microscope) analysis at room temperature (RT). Enhanced surface plasmon resonance (SPR) absorbance UV visible optical spectra were detected in the range of 552, 548, 558 and 536 nm. SEM and DLS (transmission mode) analysis confirmed the morphology of the nanoparticles to be spherical with the average size in the range of 88.37, 94.31, 82.23 and 81.36 nm. Further they have enhanced the enzyme activity on α-amylase, cellulase, and xylanase. The results suggest that the phyto-fabricated AuNPs from R. tuberosa and P. acidus is simple, less expensive, eco-friendly, green synthesis and also can be exploited for the potential future industrial and bio-medical applications.

Associations Between the Macroeconomic Indicators and Suicide Rates in India: Two Ecological Studies

BACKGROUND

While western studies have focused on the importance of psychiatric illnesses in the complex pathways leading to suicides, several Indian studies have highlighted the important contributions by economic, social, and cultural factors. Hence, we tested the hypothesis that annual national suicide rates and suicide rates of the different states in India were associated with macroeconomic indices.

MATERIALS AND METHODS

Data from the National crime records bureau, Ministry of finance, labour bureau, Government of India, population commission, and planning commission official portals, World Bank and the United Nations were accessed. We assessed the correlations of annual national and state-wise suicide rates with macroeconomic, health, and other indices using ecological study design for India, and for its different states and union territories.

RESULTS

We documented statistically significant associations between the suicide rates and per capita gross domestic product, consumer price index, foreign exchange, trade balance, total health expenditure as well as literacy rates.

CONCLUSIONS

As recent economic growth in India is associated with increasing suicide rates, macroeconomic policies emphasizing equitable distribution of resources may help curtailing the population suicide rates in India.

Quantum chemical investigations on the effect of dodecyloxy chromophore in 4-amino stilbene sensitizer for DSSCs

Stilbene based metal free organic dye sensitizer has been designed first time for dye sensitized solar cells applications. The geometries, electronic structures and dipole moment of the chosen 4-amino-4'-dodecyloxy-stilbene dye sensitizer has been analyzed by using Density Functional Theory (DFT) and Time Dependent DFT (TD-DFT) calculations (based on hybrid functional B3LYP). The HOMO and LUMO energies of the dye 4-amino-4'-dodecyloxy-stilbene are -4.95 and -0.87 eV respectively calculated by using TD-DFT. To understand the conversion efficiency of the chosen dye architecture unit we selected TiO2 as a model for semiconductor. The values of polarizability and hyperpolarizability are 165. 94 and 347.74 a.u respectively based on DFT calculations. Results reveal that the selected dye sensitizer exhibits large dipole moment difference between the ground and excited state which is comparable to that of metal based dye sensitizers. Further the large dipole moment would be expected to give high photo-current conversion efficiency in practical DSSCs and also it is a promising candidate as a sensitizer for DSSC applications.

Effect of donor (tetradecyloxy) and acceptor (carboxamide) groups in trans-stilbene for DSSCs: quantum chemical investigations

Incorporation of tetradecyloxy and carboxamide groups in trans-stilbene molecule (dye) has been investigated first time for Dye Sensitized Solar Cells (DSSCs) applications. To understand the changes in electronic structure, geometry, dipole moment and polarizability of the mentioned dye architecture has been carried out by using density functional theory (DFT) and time dependent DFT calculations using hybrid functional B3LYP method. Further, the semiconductor TiO2 is also used as a model to evaluate the photo conversion efficiency of the chosen dye architecture. Results reveal that tetradecyloxy and carboxamide groups act as an excellent donor and acceptor groups respectively which give rise to larger difference in excited state dipole moment than the ground state. This kind of stilbene based metal free organic dyes are act as a promising sensitizer for practical DSSCs applications.

Effects of selected heavy metals (Pb, Cu, Ni, and Cd) in the aquatic medium on the restoration potential and accumulation in the stem cuttings of the terrestrial plant, Talinum triangulare Linn

The heavy metal (Cu, Pb, Ni, and Cd) accumulation capacity of the stem cuttings of the terrestrial, ornamental plant, Talinum triangulare was assessed in hydroponic medium. The stem cuttings of T. triangulare, grew well in distilled water regenerating roots and aerial parts. On exposure to various concentrations of Cu, Pb, Ni, and Cd, a concentration dependent decrease was observed in the number of leaves produced and roots regenerated and an increase in the number of days required for the initiation of roots. The number of leaves produced showed an increasing trend in almost all treatment concentrations of Cu, Pb, Ni, and Cd with an increase in the duration of experiment, whereas, with an increase in the treatment concentration of metals a significant (P < 0.05) decrease was observed in the number of leaves produced. The number of days required for root initiation in metal solutions, however, increased with increasing concentration of Cu, Pb, Ni, and Cd. The root development was completely arrested from 10 mg l(-1) of Ni and 4 mg l(-1) of Cd. Compared to the control, a significant decrease was recorded in the number of roots produced in all treatment concentrations of Cu, Pb, Ni, and Cd. Pink colouration of metal solution consequent to leaching of plant pigment from T. triangulare was observed which was not persistent and disappeared after a few days. Decaying of stem was observed when exposed to Ni and Cd but not to Cu and Pb. Although, copper accumulation by T. triangulare at treatment concentration of 15 and 20 mg l(-1) exceeded 1,000 mg kg(-1) dry matter, necessary pot culture experiment is required before "T. triangulare" can be definitely classified as a Cu hyperaccumulator.

Preliminary phytochemical studies for the quantification of secondary metabolites of medicinal importance in the plant, Acalypha fruticosa Forssk

The medicinal plant, Acalypha fruticosa Forssk for the treatment of dyspepsia, stomachache, fever, jaundice, skin diseases and even as an antidote is generally distributed in different environments of tropical region in Coimbatore district of Tamil Nadu. However, its occurrence is more common in lower hills of Western Ghats and other habitats in this region where the soil is stony with low moisture. So far, there was no study on the influence of habitat conditions on the change in the content of secondary metabolites of medicinal importance in this plant. Hence to know the changes in the content of such secondary metabolites in the leaves of A. fruticosa, the present study was undertaken in three different habitats. Thin layer chromatography revealed the presence of phytochemical compounds viz., alkaloids, flavonoids and saponins in the leaves of all the three populations. Further the content of all these compounds are found to be higher in the population of dry habitats.

In Vitro Organogenesis of Lycianthes bigeminata Bitter

Lycianthes bigeminata Bitter (Solanaceae) is an important medicinal herb distributed in the sholas of Nilgiris and chiefly used for curing ulcer. It is reported that the species is present in the sholas with poor population size in comparison to other constituent species. Owing to the demand and subsequent exploitation, it is predicted that it may occupy still poor association in the sholas of Nilgiris in course of time. Hence in vitro regeneration through employing tissue culture technique is needed. The preliminary attempt in the present study reports that the MS medium supplemented with Benzyl Amino Purine (BAP) and Naphthalene Amino Acid (NAA) at 0.5 mg/l each, induced effective callus formation. However further studies on hardening is suggested to know the survivability of this species.

Effects of copper sulfate and copper nitrate in aquatic medium on the restoration potential and accumulation of copper in stem cuttings of the terrestrial medicinal plant, Portulaca oleracea linn

The stem cuttings of the terrestrial, ornamental plant, Portulaca oleracea, grew well in distilled water by producing adventitious roots and leaves. However, when exposed to various concentrations of sulfate and nitrate salts of copper resulted in a suppression of root growth, increase in initiation time of roots and sprouts and decay of stem cuttings from the cut open end, decrease in number of leaves with an increase in concentration of copper in the growth medium. Accumulation of copper increased with increasing concentrations of both copper sulfate and copper nitrate. However, copper accumulation was greater in copper nitrate than in copper sulfate treatment. Hence, copper in the presence of nitrate is more toxic than in the presence of sulfate. The accumulation factors in all treatment concentrations were greater than 1, hence P. oleracea is a copper accumulator.

Copper availability and accumulation by Portulaca oleracea Linn. stem cutting

The Cu accumulation capacity of stem cuttings of Portulaca oleracea was assessed in two different soils, alfisol and vertisol, which differ from each other mainly due to their clay content - several fold lower in the former than in the latter. The DTPA extractable concentration of Cu in soil and the level of its accumulation in stem cuttings were, therefore, greater in alfisol than in vertisol. In the mixed soils, the DTPA extractable as well as plant accumulated levels of Cu decreased with an increase in the proportion of vertisol. With an increase in the soil available and plant accumulated Cu, a decrease has been observed in the ability of stem cuttings to regenerate leaves and roots. As a consequence biomass reduction has been observed with an increase in the concentration of Cu in the soil and plant body. In view of comparatively low availability of Cu in vertisol, regeneration of stem cuttings occurred up to a concentration of 1600 microg of Cu/g of soil, whereas in alfisol it occurred only up to 200 microg of Cu/g of soil. The results of the present study showed that P. oleracea stem cutting is an accumulator of Cu and the availability of Cu in soils could be manipulated through addition of clay since the plant available concentration of Cu is less in the soil (vertisol) with high clay content.

Prosopis juliflora--a green solution to decontaminate heavy metal (Cu and Cd) contaminated soils

Soil and plant samples (root and shoot) of Prosopis juliflora were collected in the vicinity of metal based foundry units in Coimbatore and assessed for their heavy metal content (Cu and Cd) to ascertain the use of P. juliflora as a green solution to decontaminate soils contaminated with Cu and Cd. The results showed that Cu and Cd content was much higher in plant components compared to their extractable level in the soil. Furthermore, there exist a strong correlation between the distance of the sources of industrial units and accumulation of heavy metals in plants. Accumulation of Cd in roots is comparatively higher than that of shoots. However, in case of Cu no such clear trend is seen. Considering the accumulation efficiency and tolerance of P. juliflora to Cd and Cu, this plant can be explored further for the decontamination of metal polluted soils. On the other hand, in view of heavy metal accumulate the practice of providing foliage and pods as fodder for live stock should be avoided.

Ultrasound mediated alkaline hydrolysis of methyl benzoate--reinvestigation with crucial parameters

In the present work hydrolysis of methyl benzoate was carried out using aqueous sodium hydroxide solution at room temperature in the presence of ultrasound since otherwise the same reaction takes place at relatively high temperature. Also, the above hydrolysis reaction was investigated at a relatively larger scale with the variation in parameters influencing the emulsification process and hence the reaction rates. It has been observed that the position of ultrasound source on the liquid-liquid interface is a crucial parameter affecting the two-phase emulsification rates. The poor bulk mixing occurring in the presence of ultrasound alone with an increase in the volume of the reaction mixture and its consequent effect on the reaction kinetics has been conclusively established. These studies have shown that the use of ultrasound with mechanical stirring can result in substantial reduction in the overall power consumption, especially for reaction systems like hydrolysis that do not require very high temperatures and pressures generated by cavitation.

Activated carbon prepared from biomass as adsorbent: elimination of Ni(II) from aqueous solution

Activated carbon (AC) prepared from waste Parthenium was used to eliminate Ni(lI) from aqueous solution by adsorption. Batch mode adsorption experiments are carried out, by varying contact time, metal ion concentration, carbon concentration, pH and desorption to assess kinetic and equilibrium parameters. They allowed initial adsorption coefficient, adsorption rate constant and maximum adsorption capacities to be computed. The adsorption data were modeled by using both Langmuir and Freundlich classical adsorption isotherms. The adsorption capacity (Q0) calculated from the Langmuir isotherm was 54.35 mg Ni(II)/g of AC at initial pH of 5.0 and 20 degrees C, for the particle size 250-500 microm. Increase in pH from 2 to 10 increased percent removal of metal ion. The regeneration by HCl of Ni(II)-saturated carbon by HCl, allowed suggestion of an adsorption mechanism by ion-exchange between metal ion and H+ ions on the AC surfaces. Quantitative recovery of Ni(II) was possible with HCl.

Carbon from Cassava peel, an agricultural waste, as an adsorbent in the removal of dyes and metal ions from aqueous solution

Cassava (Manihot esculenta) is a short lived erect perennial shrub, planted vegetatively from hard wood stem cuttings. It is an important crop across a wide range of tropical environments and is a significant component of cropping systems. Cassava peel is an agricultural waste from the food processing industry. Activated carbons prepared from waste cassava peel employing physical and chemical methods were tested for their efficiency in the removal of dyes and metal ions from aqueous solution. While both of these were efficient as adsorbents for dyes and metal ions, the material impregnated with H3PO4 showed higher efficiency than the heat treated materials.

Mulberry-silkworm food chain--a templet to assess heavy metal mobility in terrestrial ecosystems

Assessment of the food chain mobility of heavy metals in the natural ecosystem receives more attention nowadays. In the present study, mulberry-silkworm food chain has been focused as a templet to assess the biomobility of heavy metals in soil-higher plant-insect hierarchy. Both in the case of Cd and Cu treatments, higher mobility was observed in the level-1 (soil-root) followed by level-3 (leaf-larva), level-4 (larvae-faecal) and level-2 (root-leaf). Consequently, roots accumulated more amounts of Cd and Cu, with a limited transport to the leaves. Among the two metals (Cd and Cu) tested, in the plant, the transfer potential of Cd exceeds that of Cu. Whereas in the case of leaf-larval transfer, Cu precedes over Cd. Accumulation of Cd and Cu in all the levels (1-4) tested showed a concentration dependent increase, except in the level 4 (larva-faecal) of Cd treatment where a declining trend was noticed.