The degradation of Reactive Yellow 18 (RY-18), induced by gamma radiation in aqueous medium, was carried out as a function of gamma radiation dose (5–20 kGy) and concentration of hydrogen peroxide, the initial dye concentration and pH of the solution were optimized for the maximum degradation efficiency. Gamma radiations alone and in combination with H2O2 were used to degrade the RY-18. A degradation rate of 99% was achieved using an absorbed dose of 20 kGy, 0.6 mL H2O2 in acidic pH. Variations in the functional groups of untreated and treated RY-18 were determined by FTIR analysis. The LCMS technique was used to determine the intermediates formed during the degradation process. The cytotoxicity and mutagenicity of RY-18 were studied by hemolytic and Ames tests, respectively. There were significant reductions in cytotoxicity and mutagenicity in response to gamma radiation treatment. Cytotoxicity was reduced from 15.1% to 7.6% after treatment with a 20 kGy absorbed dose of gamma radiations with 0.6 mL H2O2. Mutagenicity was reduced by 81.3% and 82.3% against the bacterial strains TA98 and TA100 after treatment with a 20 kGy absorbed dose with 0.6 mL H2O2. The advanced oxidation process efficiency was evaluated using the byproduct formations, which were low-molecular-weight organic acid units, which through further oxidation were converted into carbon dioxide and water end products. Based on RY-18 degradation, cytotoxicity and mutagenicity reduction, the gamma radiation in combination with H2O2 has potential for the removal of dye from the effluents.
The secondary metabolites in plants are the basis of defense and stress balance, which is an important aspect in plant growth. The UV-B treatment (a biotic stress) and salt stress on bitter melon (Momordica charantia L.) were studied, and the impact of pre-sowing seed treatment was evaluated on the basis of biochemical and enzymatic biomarkers, antioxidants, and wound-healing potential during early growth stages. The UV-B treatment for 5 and 10 min and salt stress 250 mM and 500 mM treatments were applied, and 21-day seedling tissue were collected for total phenolic contents (TPC), total flavonoid contents (TFC), antioxidant, chlorophyll contents, hydrogen peroxide, total soluble sugar, enzymes activities, and wound-healing potential studies. The TPC, TFC, diphenyl picrylhydrazyl (DPPH), chlorophyll contents, and total soluble sugar were recorded higher at 5 min treatment with UV-B and salt stress at 250 mM concentration. Antioxidant enzymes activities were recorded higher for 10 min UV-B treatment and 500 mM salt treatment. Wound-healing potential was found significant at 5 min treatment with UV-B radiation, which was studied in vivo in rabbits. The LC-MS analysis revealed a variety of phenolic compounds in the seedlings. The study concluded that treatments significantly affect the biological activities of bitter melon seeds at the seedling stage, and the seeds contain important phenolic compounds responsible for its antioxidant potential and enzymatic activities. Future studies could be focused on the later stages of growth, development, and yield characteristics subjected to salt stress along with UV-B radiation treatment.