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In this study, a low-cost biosorbent was prepared using Populas nigra leaves as biomass. The leaves were modified chemically by nitric acid/calcium chloride and characterized through different instrumental techniques (Fourier transformed infrared spectroscopy, scanning electron microscopy and surface area analyzer). The prepared biosorbent was used as adsorbent for the removal of Cd(II), Cr(VI) and Pb(II) ions from aqueous media. Biosorption was studied as a function of pH (2–7), biosorbent dose (1–30 mg/L), contact time (5–120 min), and initial metal ion concentration (20–700 mg/L) at a shaking speed of 170 rpm. The experimental isothermal data were analyzed by the Langmuir and Freundlich isotherm models. The maximum monolayer biosorption capacity of Cd(II), Cr(VI), and Pb(II) was found to be 107.526, 208.3, and 172.413 mg g–1, respectively, with best fitting obtained for Langmuir model. Kinetic data fitted well to the pseudo-second order equation rather than the pseudo-first order equation. The thermodynamic parameters such as standard enthalpy change (ΔH°), entropy change (ΔS°), and Gibbs free energy (ΔG°) determined suggest that biosorption of these metals by this biosorbent is an exothermic, spontaneous and favorable process. Keywords: Biosorption; Langmuir isotherm; Freundlich isotherm; Thermodynamic parameters; Kinetic models

The current investigation deals with the removal of Pb (II), Cd (II), and Cr (VI) ions by using chemically modified Quercus dilatataleaves (CMQDL) treated with nitric acid (HNO3), and calcium chloride (CaCl2). Batch biosorption experiments were performed to determine the optimal conditions of pH, biomass dose, temperature, contact time, and initial metal concentration for the utmost removal of heavy metals from water. The structural morphology and functionalities were explained by SEM and FTIR analysis. The maximum biosorption capacities for remediation of Pb (II), Cd (II), and Cr (VI) ions viaCMQDL were 17.54, 20.408, 20.83 mg g−1, respectively at the optimal conditions. The Langmuir and Freundlich isotherm were applied to explore the equilibrium data however Freundlich isotherm model best evaluate the equilibrium data with high regression correlation coefficient (R2) values of 0.985, 0.826, and 0.919 for the elimination of Pb (II) Cd (II), and Cr (VI) ions, respectively. The kinetic study proposed that the remediation operation best obeyed the kinetic pseudo 2nd order model. The calculated thermodynamics functions like change in entropy (ΔS°), change in enthalpy (ΔH°) and Gibbs free energy (ΔG°) revealed that the removal of Pb (II) ions viathe CMQDL was viable, exothermic and spontaneous, Cd (II) was endothermic and spontaneous and Cr (VI) was endothermic and non-spontaneous. The current study explored that CMQDL can be used for the remediation of Pb (II), Cd (II), and Cr (VI) ions, respectively.

This study deals with biosorption of Pb(II), Cd(II) and Cr(VI) from an aqueous solution using chemically modified Bauhinia variegata leaves (CMBVL); a low cost adsorbent under different experimental conditions likes initial heavy metals concentration (20–500 mg/L), contact time (10–120 min), pH (1–7), and biosorbent dose (1–30 g/L). The biosorption of the selected heavy metals follow Langmuir isotherm more effectively rather than the Freundlich model. The maximum biosorption capacity (qmax) of CMBVL for Pb(II), Cd(II) and Cr(VI) were; 92.592, 114.943, and 70.921 mg/g, respectively. Based on regression correlation coefficients (R2) value the kinetic data were best fitted into second-order kinetic model rather than the first-order kinetic equation. The calculated thermodynamic parameters like standard enthalpy change (∆H°), standard entropy change (∆S°), and standard Gibb’s free energy (∆G°) indicated that the biosorption of the selected metals was an exothermic, spontaneous, and favorable process. Based on our results, it can be concluded that CMBVL could be effectively extended as biosorbent for the removal of heavy metals from industrial effluents.

In this study, the green mediated biosorption of Pb(II) onto chemically modified Grewia optiva leaves (CMGOL) has been investigated. To improve the biosorption capacity, Grewia optiva leaves powder were treated with HNO3, then neutralized and finally activated with CaCl2. The prepared adsorbent was characterized by analytical tools such as Fourier-transform infrared spectroscopy, scanning electron microscopy, and Brunauer–Emmett–Teller surface area analyzer. To determine the optimum parameters of the biosorption process, batch experiments were performed under different conditions of pH (2–7), contact time (5–180 min), biosorbent dosage (0.1–30 g/L), initial metal concentration (10–800 mg/L), and temperature (25°C–50°C). Optimal biosorption of Pb was achieved at pH 6, biosorbent dosage 5 g/L, contact time 120 min, initial Pb concentration 100 mg/L, and temperature of 50°C. Correlation coefficient R2value (0.967) of Langmuir adsorption model (monolayer adsorption capacity = 135.136 mg/g) was high as compared to the Freundlich adsorption model and thus fitted well the equilibrium adsorption data. Kinetic studies revealed that Pb biosorption data fitted well to the pseudo-second-order equation rather than the pseudo-firstorder equation. The values of thermodynamic parameters ∆H° and ∆G° were negative while that of ∆S° was positive indicating favorable and spontaneous nature of the biosorption process. Due to high biosorption capacity (135.136 mg/g) the prepared CMGOL could be used effectively for the removal of Pb from wastewaters.

AbstractTwo new alkaloids, 17-desoxy-cfs-lamprolobine (1) and bonzakaline (2), along with the known alkaloids lupanine (3) and palmatrubine (4), have been isolated from the ethanolic extracts of Bongardia chrysogonum.Compounds 1and 2have shown antibacterial activity against Proteus mirabilis, Proteus vulgaris, Klebsiella pneumoniae, Escherichia coliand Shigella dysenteriae.the structure elucidation was performed by using various spectroscopic methods including 2D NMR techniques1,2.

Two new alkaloids, 17-desoxy-cfs-lamprolobine (1) and bonzakaline (2), along with the known alkaloids lupanine (3) and palmatrubine (4), have been isolated from the ethanolic extracts of Bongardia chrysogonum. Compounds 1 and 2 have shown antibacterial activity against Proteus mirabilis, Proteus vulgaris, Klebsiella pneumoniae, Escherichia coli and Shigella dysenteriae. the structure elucidation was performed by using various spectroscopic methods including 2D NMR techniques1,2.

Lentil is a major protein crop, consumed as food across the globe to fulfill protein requirements. Because of increase demand and significant economic importance, its production should increase. In the present investigation, gradual decrease in germination percentage, plant survival and pollen fertility of mutagenic treated population was observed in M1generation. Qualitative and quantitative traits were also affected due to mutagenic treatment and the sensitivity was found highest in EMS followed by caffeine. Meiotic studies revealed high frequency of chromosomal aberration in EMS as compared to caffeine. Agronomic trait analysis showed inter and intra treatment phenotypic variations such as plant height, branches per plant and seed yield. Estimation of mutant recovery rate in M2generation showed higher recovery in 0.75, 1.0% caffeine and 0.75% EMS followed by 1.0% EMS. In the present examination, phenotypic categories of mutants associated with the vegetative organs (plant size, plant habits, leaf morphology) were dominant representing >60% followed by seed color, size, shape and germination of total phenotypes of both mutagenic M2population. A comparative account on number of mutants and phenotype category in M2plants showed that pleiotropic mutants were higher than non pleiotropic mutants. The heritability and reproducibility of 29 putative mutants were analyzed in M3generation on the basis of observed agro-economical traits which showed 18 complete and 5 partial heritable mutants.

Stem barks derived from twenty-one medicinal plants were extracted in methanol (100%) and acetone-water (70 : 30 v/v) and at room as well as at reflux temperature conditions. Total phenolic contents, determined using FC (Folin Ciocalteu) reagent, ranged from 528 to 715 mg GAE/g of crude extract. 15 out of 21 plants showed DPPH activity more than 90% and the rest of plants exhibited the activity in the range of 87–89%. The methanolic extract of P. granatum obtained at room temperature showed the highest antiradical activity (96%). The extracts with similar % radical scavenging of DPPH∙ showed significant variation in EC50 value. Radical scavenging activity of E. rostrata, M. champaca, A. modesta, P. roxburghii, P. longifolia, E. suberosa, and F. infectoria was evaluated for the first time. A strong correlation between total phenols and antiradical activity was exhibited with R values ranging from 0.7580 to 0.8874 indicating a linear relationship The extracts phenolic composition was studied by HPLC. All extracts showed remarkable antioxidant activity (87 to 96%) while moderate activity was exhibited against protease (22 to 56%). Gallic acid, tannic acid, quercetin, rutin, catechin, hesperidin, and cinnamic acid were identified as the major phenolic acids in the extracts of selected medicinal plants.

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