Thiazole-pyrazoline Schiff base hybrids have a broad range of pharmacological potential with an ability to control the activity of numerous metabolic enzymes. In this work, a greener and more efficient approach has been developed to synthesize a novel series of thiazole-pyrazoline Schiff base hybrids using ZnO nanoparticle-assisted protocol in good to excellent yields (78.3–96.9%) and examined their antibacterial activity against Gram-positive and Gram-negative bacteria, as well as their antioxidant activity. Compound 24 (IZD = 18.67 ± 0.58) displayed better activity against P. aeruginosa compared with amoxicillin (IZD = 14.33 ± 2.52) at 250 μg/mL, whereas compounds 22 and 24 (IZD = 13.33 ± 0.58 mm and 17.00 ± 1.00 mm, respectively) showed better activity against E. coli compared with amoxicillin (IZD = 14.67 ± 0.58 mm) at 500 μg/mL. The remaining compounds showed moderate to weak activity against the tested bacterial strains. Compound 21 displayed significant inhibition of DPPH (IC50 = 4.63 μg/mL) compared with ascorbic acid (IC50 = 3.21 μg/mL). Compound 21 displayed 80.01 ± 0.07% inhibition of peroxide formation, suggesting its potential in preventing the formation of lipid peroxides. The results of the ADMET study showed that all synthesized compounds obeyed Lipinski's rule of five. In silico pharmacokinetic study demonstrated that compound 24 had superior intestinal absorption compared with amoxicillin. In silico molecular docking analysis revealed a binding affinity of −9.9 Kcal/mol for compound 24 against PqsA compared with amoxicillin (−7.3 Kcal/mol), whereas compounds 22 and 24 displayed higher binding affinity (−8.5 and −7.9 Kcal/mol, respectively) with DNA gyrase B compared with amoxicillin (-7.1 Kcal/mol), in good agreement with in vitro antibacterial activity against P. aeruginosa and E. coli. In silico toxicity study showed that all synthesized compounds had LD50 (mg/kg) values ranging from 800 to 1,000 putting them in ProTox-II class 4. The in vitro antibacterial activity and molecular docking analysis showed that compound 24 is a promising antibacterial therapeutic agent against P. aeruginosa and E. coli and compound 22 is a promising antibacterial agent against E. coli, whereas compound 21 is found to be a potential natural antioxidant agent. Moreover, the green synthesis approach using ZnO nanoparticle as catalyst was found to be a very efficient method to synthesize biologically active thiazole-pyrazoline Schiff base hybrids compared with the conventional method.

Diminishing supply and environmental pollution of fossil fuels are the vital factors leading to the search of alternative sources of energy like biodiesel. Biodiesel is one of the eco-friendly substitutes of energy which is mainly utilized in diesel engines. Ricinus communis (castor plant), which belongs to the family Euphorbiaceae yields an oil rich beans and plays important role in the production of biodiesel. Recently, the demand of castor oil and its products has been raised in the world market due to its versatility to use and simplicity to produce. Therefore, this study investigates the extraction of castor oil and its conversion in to biodiesel via alkali catalyzed transesterification. The seed oil of the plant was extracted using Soxhlet apparatus and the quality of the biodiesel was examined using the standard procedures of American standards for testing methods. Furthermore, the chemical composition of the extracted oil was examined using GC-MS. The seed oil was liquid at room temperature (25 °C), golden yellow in color with a nutty odor. The extraction processes yielded 324 g (9.25% w/w) and 78% of oil and biodiesel respectively. The density (0.86 g/mL), viscosity (5.42 mm 2 s -1 ), flash point (87 °C), acid value (0.35 mg KOH/g), water content (0.80%), iodine value (108.60), and cetane number (58.00) were reported in this study and showed a good agreement with the standards of biodiesel. GC-MS analysis of the seed oil also showed the presence of 10 different fatty acids (9-Octadecenoic acid, 12-hydroxy-, methyl ester, [R-(Z)] took the highest composition) which plays significant role for the production of methyl esters. So, the study can assure that castor oil can be used for commercial production of biodiesel at cost effective scales.

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This study was conducted to assess the presence of pesticides residues in wheat from Misha woreda, Haiya Zone, Ethiopia. Samples of wheat were collected during the period December 2015 to August 2016. Gas chromatograph (GC-MS) detection was employed after Liquid-Liquid extraction (LLE). The concentration levels of eight pesticides have been investigated in both wheat samples in farm and purchased from storage facilities. Since the method was out of scope, it was validated before application to the analysis of these pesticides. The spiked recovery results for five analytes were within the acceptable international standard. The LOD value and LOQ value are below the LCC and MRL of the analyte. Method validation for this study maintained a RSD <20% and percentage recoveries were in the range of 80-110%. The %RSD of all detected analytes was less than the acceptable international standard. Results show that out of the residues of eight analytes determined, four analytes (2,4-D; aldrin; Endosulfan; p,p-DDT) were detected in both field (pre harvest) samples and stored (post harvested) sample, whereas the remaining analytes were not detected at all. In general, the concentrations of these analytes in the wheat samples are in the order: 2, 4-D >aldrin>p,p-DDT >Endosulfan. The study observed that from the detected analytes, none of them are above the international MRL values and suggested that stringent monitoring of use of pesticides in agriculture and food storage is required.

In the present study, a new series of nine Thiazolo[3,2-α] pyrimidine analogs were synthesized in good to excellent yields (87.9–96.9%) and improved reaction time using a ZnO nanoparticle-assisted protocol. All the synthesized compounds were characterized using a combination of physicochemical parameters, UV-visible, 1H-NMR, and 13C-NMR spectroscopic methods. Among the synthesized compounds, the in vitro antibacterial activity displayed by compound 16 was higher (14.67 ± 0.58 mm at 500 μg/mL) against P. aeruginosa compared to amoxicillin (12.33 ± 0.58 mm at 500 μg/mL), whereas compounds 14 and 18 showed comparable activity (12.00 ± 0.00 mm and 12.33 ± 0.58 mm at 500 μg/mL and 250 μg/mL, respectively) against the same strain. The activities displayed by compounds 14, 16, 18, and 20 were comparable (12.33 ± 1.15 mm, 12.65 ± 0.58 mm, 12.33 ± 0.58 mm, and 12.00 ± 1.00 mm, respectively, at 500 μg/mL) to amoxicillin (13.33 ± 1.15 mm at the same concentration) against E. coli. Compound 19 showed good activity (12.00 ± 1.72 mm at 500 μg/mL) against S. aureus compared to amoxicillin (16.33 ± 0.58 mm at the same concentration). Compound 19 displayed the highest percent inhibition of DPPH with an IC50 value of 9.48 g/mL using the DPPH free radical scavenging assay compared to ascorbic acid (3.21 g/mL) and promising inhibition of peroxide formation (76.28 ± 0.12%), demonstrating its potential in preventing the formation of lipid peroxides. Thus, according to our findings, both the biological activities and in silico computational results revealed that compounds 14, 16, and 18 are good antibacterial agents against P. aeruginosa and E. coli, whereas compound 19 was found to be a promising antibacterial agent against S. aureus and an antioxidant agent. The present study revealed that the synthesized compounds appear to be lead compounds for rational drug design.