The adsorptive removal of hexavalent chromium Cr(VI) from aqueous solutions was investigated by acrylonitrile grafted banana peels (GBPs). Banana peels were treated with 10% HCl, followed by alkaline hydrolysis with 10% NaOH, and washed thoroughly. The bleaching of alkali hydrolyzed peels was carried out with sodium chlorate (NaClO3) in the presence of hydrogen peroxide and glacial acetic acid. The grafting co-polymerization of acrylonitrile onto the bleached pulp was initiated by Fenton’s reagent (Fe+2/H2O2). The optimum conditions for adsorption of Cr(VI) were found to be the following: pH 3, adsorbent dose 4g/L, concentration 400mg/L and contact time of 120min. The surface morphology of adsorbent was characterized by scanning electron microscopy (SEM) before and after the adsorption. The adsorption of Cr(VI) onto grafted banana peels (GBPs) was recorded to be 96%. The adsorption data were fully fitted with the Freundlich and Langmuir isotherm model and followed a pseudo-second order kinetic model. Thermodynamic study showed that the adsorption is exothermic and spontaneous. Owing to high efficiency and low cost, grafted banana peels (GBPs) can be used as effective adsorbent for Cr(VI) removal from wastewater

The utilization of biochar, derived from agricultural waste, has garnered attention as a valuable material for enhancing soil properties and serving as a substitute adsorbent for the elimination of hazardous heavy metals and organic contaminants from wastewater. In the present investigation, amide-modified biochar was synthesized via low-temperature pyrolysis of rice husk and was harnessed for the removal of Cr(VI) from wastewater. The resultant biochar was treated with 1-[3-(trimethoxysilyl) propyl] urea to incorporate an amide group. The amide-modified biochar was characterized by employing Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) techniques. During batch experiments, the effect of various parameters, such as adsorbent dosage, metal concentration, time duration, and pH, on Cr(VI) removal was investigated. The optimal conditions for achieving maximum adsorption of Cr(VI) were observed at a pH 2, an adsorbent time of 60 min, an adsorbent dosage of 2 g/L, and a metal concentration of 100 mg/L. The percent removal efficiency of 97% was recorded for the removal of Cr(VI) under optimal conditions using amide-modified biochar. Freundlich, Langmuir, and Temkin isotherm models were utilized to calculate the adsorption data and determine the optimal fitting model. It was found that the adsorption data fitted well with the Langmuir isotherm model. A kinetics study revealed that the Cr(VI) adsorption onto ABC followed a pseudo-second-order kinetic model. The findings of this study indicate that amide-functionalized biochar has the potential to serve as an economically viable substitute adsorbent for the efficient removal of Cr(VI) from wastewater.

Medicinal plants play important role in the public health sector worldwide. Natural products from medicinal plants are sources of unlimited opportunities for new drug leads because of their unique chemical diversity. Researchers have focused on exploring herbal products as potential sources for the treatment of cancer, cardiac and infectious diseases. Arisaema flavum (Forssk.) is an important medicinal plant found in the northwest Himalayan regions of Pakistan. It is a poisonous plant and is used as a remedy against snake bites and scorpion stings. In this study, two bioactive compounds were isolated from Arisaema flavum (Forssk.) and their anticancer activity was evaluated against human breast cancer cell line MCF-7 using an MTT assay. The crude extract of Arisaema flavum (Forssk.) was subjected to fractionation using different organic solvents in increasing order of polarity. The fraction indicating maximum activity was then taken for isolation of bioactive compounds using various chromatographic and spectroscopic techniques such as column chromatography, thin-layer chromatography (TLC), gas chromatography–mass spectrometry (GC-MS), Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR). Crude extract of Arisaema flavum (Forssk.), as well as various fractions extracted in different solvents such as n-hexane, chloroform and ethyl acetate, were tested against human breast cancer cell line MCF-7 using an MTT assay. The crude extract exhibited significant dose-dependent anticancer activity with a maximum activity of 78.6% at 500 µg/mL concentration. Two compounds, hexadecanoic acid ethyl ester with molecular formula C₁₈H₃₆O₇ and molar mass 284 and 5-Oxo-19 propyl-docosanoic acid methyl ester with molecular formula C₂₆H₅₀O₃ and molecular mass 410, were isolated from chloroform fraction. These compounds were tested against the MCF-7cell line for cytotoxic activity and exhibited a significant (p < 0.00l) decrease in cell numbers for MCF-7 cells with IC₅₀ of 25 µM after 48 h of treatment. Results indicated that Arisaema flavum (Forssk.) possesses compounds with cytotoxic activity that can further be exploited to develop anticancer formulations.