The oxidative stability and compositional characteristics of the pumpkin seed oil (PSO) exposed to microwaves were studied during heating at 170°C. The oxidative indices such as free fatty acid (FFA), peroxide value (PV), p-anisidine value (p-AV), TOTOX, specific extinctions and thiobarbituric acid (TBA) value of oils were significantly increased, and the increments were found to be significantly higher (P < 0.05) in unroasted seed oil as compared to roasted seed oil. The relative contents of polyunsaturated fatty acids (PUFAs) were decreased to 84.7%, and saturated fatty acids (SFAs) were increased to 119.5% in unroasted sample, after 9 h of heating. On the other hand, in 12 min roasted samples, the relative contents of PUFAs were decreased to 97.0%, and SFAs were increased to 102.6% after 9 h of heating. The triacylglycerol species LLL and OLL levels were decreased as a consequence of increased heating time, and the reduction tended to be significantly higher in unroasted samples as compared to roasted ones. The oxidation products formed were also investigated by FTIR. The present results indicated that microwave roasting of pumpkin seeds markedly enhanced the oxidative stability of the oils during heating.

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Activated carbon (AC) has been extensively utilized as an adsorbent over the past few decades. AC has widespread applications, including the removal of different contaminants from water and wastewater, and it is also being used in capacitors, battery electrodes, catalytic supports, and gas storage materials because of its specific characteristics e.g., high surface area with electrical properties. The production of AC from naturally occurring precursors (e.g., coal, biomass, coconut shell, sugarcane bagasse, and so on) is highly interesting in terms of the material applications in chemistry; however, recently much focus has been placed on the use of agricultural wastes (e.g., rice husk) to produce AC. Rice husk (RH) is an abundant as well as cheap material which can be converted into AC for various applications. Various pollutants such as textile dyes, organic contaminants, inorganic anions, pesticides, and heavy metals can be effectively removed by RH-derived AC. In addition, RH-derived AC has been applied in supercapacitors, electrodes for Li-ion batteries, catalytic support, and energy storage, among other uses. Cost-effective synthesis of AC can be an alternative for AC production. Therefore, this review mainly covers different synthetic routes and applications of AC produced from RH precursors. Different environmental, catalytic, and energy applications have been pinpointed. Furthermore, AC regeneration, desorption, and relevant environmental concerns have also been covered. Future scopes for further research and development activities are also discussed. Overall, it was found that RH-derived AC has great potential for different applications which can be further explored at real scales, i.e., for industrial applications in the future.

In this study, new mixed ligand complexes have been prepared from bis(2,4,4-trimethylpentyl)dithiophosphinic acid (C16H35PS2) and 2,9-dimethyl-1,10-phenanthroline (C14H12N2) with various metal(II) ions. The molecular formula of the metal complexes were [Mn(C16H34PS2)(C14H12N2)]Cl (1), [Fe(C16H34PS2)(C14H12N2)]Cl (2), [Co(C16H34PS2) (C14H12N2)]Cl (3), [Zn(C16H34PS2)(C14H12N2)]Cl (4) and [Cd(C16H34PS2)(C14H12N2)]Cl (5). These complexes have been characterized by various physico-chemical techniques such as melting point, molar conductance, magnetic susceptibility measurements as well as UV-Vis, IR, TG and mass spectroscopic analyses. The surface morphology was determined by scanning electron microscope (SEM). The magnetic moment value, color as well as spectral measurements suggested that the geometrical structures of the metal complexes were tetrahedral. The spectral data showed that bis(2,4,4-trimethylpentyl)dithiophosphinic acid and 2,9-dimethyl-1,10-phenanthroline ligands  acted as uninegative and neutral bidentate ligand, respectively. The obtained mixed ligand complexes were more stable in air and highly soluble in common organic solvent. The bio-efficacy of ligands and metal complexes have been screened against the test microorganism using agar disc diffusion method. The complex 4 showed potential antibacterial activity against Sterptococcus aureus as compared to standard drug, imipenem. On the other hand, the complex 3 also displayed more potent antifungal activity against Lecanicillium fungicola. Moreover, the complex 3 was also found to have better scavenging activity against 2,2-diphenyl-1-picrylhydrazyl.

Thymoquinone (TQ) is a natural compound occurred in black cumin (Nigella sativa L.), which possesses potent antioxidant activity without having any phenolic hydroxyl group believed to be responsible for antioxidant activity of a molecule. In the present study, computational calculation based on Density Functional Theory (DFT) have been executed to assess systematically the worth of antioxidant behavior of this compound. Geometrical characteristics, HOMO-LUMO and MEP surface have been studied. Thermochemical parameters correlated to the leading antioxidant mechanisms such as HAT, SETPT and SPLET have been studied in gas and water media. In addition, the changes of thermochemical parameters such as ∆G and ∆H have been computed for HA from TQ to hydroxyl radical in gas and water phases to investigate its free radical scavenging potency. The low and comparable values of BDE, PDE, IP, PA and ETE suggest the antioxidant activity. The ∆G and ∆H also convey apposite thermodynamic evidence in favor of antiradical capability of TQ. The attack of the free radical takes place preferentially at 3CH position of the molecule.

on oil quality are reduced; the oil becomes suitable for human consumption. Now a days, consumers don t like to use crude oil as it contains considerable amount of unacceptable materials that produce color and odor 2 . Vegetable oils are refined by chemical or physical process to preserve the quality of oil by removing or reducing free fatty acids, phospholipids, and coloring materials that might have adverse effects on chemical composition, sensory characteristics, and stability of the oil 3 . Simultaneously, the refining process also reduces or removes some useful bioactive phytochemicals present in the unsaponifiable fraction of Abstract: The compositional characteristics and oxidative stability of rice bran oil were determined by observing the formation of oxidative products and alteration in chemical composition of oils during microwave or oven heating. The values of oxidative indicators such as free acidity, peroxide, p-anisidine, total oxidation, thiobarbituric acid and color values, increased faster in refined oils compared to crude ones during heating. In gas chromatography analysis, the percentages of total saturated, monounsaturated and polyunsaturated fatty acids in the studied oils such as lab extracted crude rice bran oil, lab extracted and refined rice bran oil, crude rice bran oil from commercial mill and refined rice bran oil from commercial mill were: 23.07 to 23.56, 41.15 to 42.38 and 34.38 to 35.88, respectively. The heating caused the reduction of polyunsaturated fatty acids content with increasing saturated fatty acids content, and these changes were greater in refined rice bran oil indicating extensive lipid oxidation occurred in refined oil. The change in triacylglycerol species content as determined by High-performance liquid chromatography, was lower in crude oil; the higher stability of these species in crude oil could have contribution to reduce oxidation. During thermal treatment, the generation of hydroperoxides, their degradation and formation of secondary oxidative products evaluated by Fourier-transform infrared spectroscopy, were lower in crude oils. However, the rate of formation of oxidative products in lab prepared samples was lower compared to that in the samples collected from commercial mill. Under extreme thermal condition, the order of oxidative stability: lab extracted crude rice bran oil > crude rice bran oil from commercial mill>lab extracted and refined rice bran oil > refined rice bran oil from commercial mill. The present results will be useful to oil seed processing mills in refining of rice bran oil for economic feasibility and better marketability.

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Textile manufacturing sector is the strongest root of the economy of Bangladesh while pollution by inappropriate management of waste water from textile dyeing industries is one of the major environmental problems. Textile processing employs an assortment of chemicals, contingent upon the idea of the crude materials and items. Environmental problems caused by the the textile industry are mainly the discharges of waste water. The wellspring of waste water contamination are the wet handling steps which incorporate measuring, desizing, scouring, bleaching, mercerizing, coloring, printing etc. The present study was aimed at physico-chemical evaluation of waste water discharged by some garments industries. While in some waste water high pH values have been recorded, the pH values of the waste water before and after treatments were found in between the standard range. The Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Dissolved Solid (TDS) and Total Suspended Solid (TSS) values for waste water before treatment were found to be much higher than the permissible limits. For some industries the BOD, COD, TDS and TSS values of the outlet water from effluent treatment plant (ETP) were also found beyond the standard limits.