No abstract

In this study, we are presenting the effect of three ripening stages of air-dried bitter gourd fruit extracts on phenolic acid composition, antioxidant, antibacterial, and anticancer activities. The results showed mature bitter gourd fruit extract in 100% methanol showing 78% DPPHº scavenging activity. Immature dried fruit extract in 80% and 100% methanol showed promising antibacterial activities, i.e., >18.5 ± 0.21 mm zone-of-inhibition against Staphylococcus aureus, while mature dried fruit extract in 80% methanol showed 18.4 ± 0.17 mm zone-of-inhibition against Escherichia coli. Anticancer activity results of 100% methanol extracts of ripened fruit possess showed 6.72 ± 1.81 and 3.55 ± 0.51 mg/mL IC50 values with HeLa and MDBK cancer cell lines, respectively. The overall results indicate that the immature and ripen fruits of BG could be extracted in pure methanol as an antibacterial and anticancer phytomedicine.

This study explores the lab prepared nickel hydroxide catalyzed oxidative degradation of Methylene Blue (MB) in aqueous medium using batch reactor. Nickel hydroxide was prepared by reaction of sodium hypochlorite, sodium hydroxide and nickel sulphate hexahydrate in distilled water. The catalytic oxidative degradation of Methylene Blue was explored in terms of various parameters like effect of time, hydrogen peroxide, temperature, initial concentration of dye, catalyst dosage and effect of speed of agitation on degradation of Methylene Blue. Experimental data was subjected to kinetics analysis using Curve Expert software. Degradation reaction was taking place according to Langmuir-Hinshelwood mechanism. According to this mechanism the reactants adsorb at the surface of catalyst in first step followed by chemical reaction between adsorbed reactants in second step. Catalyst was heterogeneous in nature which was separated by simple filtration easily.

Synthetic dyes are persistent pollutants with poor biodegradability. The present study is about the degradation of direct Congo red dye in aqueous media using the Co-60 gamma radiation source. The experimental conditions such as gamma-ray absorbed doses, amount of oxidant (H 2 O 2 ) and pH conditions were evaluated. The  max of dye solution was noted as 498 nm, and then, decrease in absorbance and reduction in chemical oxygen demand (COD) were examined. The complete colour removal of dye was observed at 5 kGy, while a signifi cant COD removal was observed at 15 kGy gamma-ray absorbed dose in conjunction with oxidant for 50 mg/L concentration. It was found that pH has no infl uence on degradation effi ciency. A possible degradation pathway was proposed. The radiolytic end products were monitored by Fourier transform infrared (FTIR) and gas chromatography coupled with mass spectrometry (GC-MS) to explore the degradation mechanism. It was imperative to study the oxidative degradation pathway to provide directions for potential applicability of advanced oxidation process (AOP) in industrial wastewater treatment.

This study focuses on synthesis of nickel oxide catalyst and exploration of its catalytic activities for degradation of methyl orange in aqueous medium. Nickel oxide was prepared sole-gel method using nickel nitrate haxahydrate and citric acid as precursor materials. X-ray diffractometry and scanning electron microscopy were used for characterization of prepared nickel oxide particles. The prepared particles were used as the catalysts for the degradation of Methyl Orange in aqueous medium. The effects of different parameters on degradation of methyl orange were investigated. The degradation of methyl orange followed the Eley-Rideal (E-R) mechanism. The apparent activation energies for degradation of methyl orange determined was found as 36.4 kJ/mol.