Papers by Obeida Al-Hajali
Journal of the Turkish Chemical Society Section A: Chemistry, 2022
Description of Pistacia leaves powder using scanning electron microscopy (SEM), Fourier transform... more Description of Pistacia leaves powder using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), Energy-dispersive X-ray spectroscopy (EDX), specific surface area according to nitrogen adsorption (SBET) and methylene Blue (MB), and point of zero charge determination (pHpzc). A series of batch adsorption tests were conducted to study effect of various factors (plant powders dose, contact time, temperature, pH) on the percentage of nitrate and phosphate removal from domestic wastewater. The adsorption kinetics, regeneration ability test of plant powder, and phytotoxicity tests for treated water and spent powder on germination were studied. Results of SBET analysis showed that Pistacia leaves powders have a low surface area and microscopic pores, SEM images revealed rough surfaces with uneven cavities, EDX analysis showed that there are high percentages of carbon and oxygen, good percentages for nitrogen, and few percentages of potassium, calcium, magnesium, phosphorous, sulfur and chlorine, and FTIR analysis showed that there are more than five distinct absorption peaks. The maximum value of nitrate and phosphate removal was 76.47% and 52.20%, respectively, at powder dose of 2 g/L, temperature 25 °C, and pH 5, and the percentage of nitrate and phosphate removal increased with increasing contact time until equilibrium was reached after 120 min for nitrate and 180 min for phosphate, and It was found that adsorption of ions follows kinetics of reaction from pseudo-second-order model, and powders can be Regeneration and used for two successive cycles with a slight decrease in removal efficiency. Germination tests on Lepidium sativum indicate no phytotoxicity. That is, Pistacia leaves powder is one of the natural products that are effective in removing nitrate and phosphate from domestic wastewater.
Journal of the Turkish Chemical Society Section A: Chemistry
The qualitative detection of phytochemical compounds of extracts was carried out using color reag... more The qualitative detection of phytochemical compounds of extracts was carried out using color reagents, total content of phenols and flavonoids was specified using Folin-Ciocalteu and aluminum chloride method, respectively, and antioxidant activity was determined through its ability to free radicals scavenging using DPPH radical. The efficacy of the plant extracts against pathogenic bacteria was studied by agar well diffusion method with different concentrations, and microdilution method was used to measure minimum inhibitory concentration (MIC) of all plant extracts. The results showed presence of tannins, phenols, and flavonoids in all extracts of both plants, while saponins were found in aqueous extracts only, cardiac glycosides and coumarins were absent in all plant extracts. Ethanolic extract of Pistacia atlantica recorded the highest content of phenols and flavonoids as 263.76 ± 0.53 (mg GAE/g Dw) and 46.83 ± 0.55 (mg RE/g Dw), respectively. While aqueous extract of Pinus canariensis recorded the lowest content of of phenols and flavonoids 30.11 ± 0.37 (mg GAE/g Dw) and 5.43 ± 0.38 (mg RE/g Dw), respectively. Both plants have been shown to have good antioxidant activity, as ethanolic extract of P. atlantica recorded the best ability to free radicals scavenging 90.27% ±1.51, ethanolic extracts of both plants were the most effective in inhibiting bacteria especially at high concentrations (500 mg/mL); the inhibition zone diameter of P. atlantica extract reached 33.56 mm against Shigella boydii, while aqueous extract of P. canariensis was the most effective against Pseudomonas aeruginosa; the inhibition zone diameter was 21 mm. MIC ranged between 5.468 and 43.75 mg/mL depending on plant extract and bacterial species. This confirms the importance of plant extracts as a natural source of antibacterial to confront problems of increasing bacterial resistance to antibiotics that threaten public health.
Uploads
Papers by Obeida Al-Hajali