Volume 23 - 2021

(E)-2-((pyren-1-ylmethylene)amino)phenol (3) containing pyrene linked through an imine bond to a phenol unit was synthesized and its Fe-complex 4 was prepared. The complex 4 is characterized by infrared (IR), x-ray diffraction (XRD) and UV-Vis spectroscopy techniques. The synthesized complex was used as a sensitizer in a solar cell structure. From the current density (J) - voltage (V) curve obtained, the values of the short-circuit current density (JSC), maximum current density (JM), open-circuit voltage (VOC) and maximum voltage (VM) for the complex 4 were determined as 6.68 mA /cm2, 4.73 mA /cm2, 0.56 V and 0.41 V, respectively. Using these parameters, the fill factor (FF) and power conversion efficiency value (η) of complex 4 were calculated as 0.52 and 1.94, respectively. This value shows that complex 4 can be used as an effective sensitiser in solar cell applications.

Regular water treatment-plant (WTP) comprises of a number of units. Of course, problems exist throughout design and operation of the WTP units. Consequently, the current re-search aimed to minimize the shortcomings of the coagulation, sedimentation, and the adsorption methods through applying optimal process for these units. Additionally, eco-nomic analysis and the derivation mathematical models for the new coagulant (Aluminum Chlorohydrate (ACH)) and the traditional aluminum sulphate coagulant (Alum) were an-other objective of this work. Optimum coagulants for alum and ACH were obtained and presented for different raw water turbidities. The optimum settling time of 30 minutes and 40 minutes have been found for the settling of 1000 and 2000 NTU raw water sam-ples. Best dosages of 0.1 and 0.25 g/L of powdered actived carbon (PAC) were obtained for raw water turbidity of 419, and 1000 NTU which increased the removal efficiency of 28.95%, and 25.71%, respectively. Furthermore, the economic study for alum and ACH revealed that using ACH instead of alum led to reduction of cost by 32%. Commonly, it can be concluded that using ACH instead of alum is better because it is cheaper and more efficient. The predicted equations for the optimum dosages (Y) for alum (mg/L) and ACH (µl/L) dosages (X) were Y= 0.04 X + 14.42, and Y = 0.01 X + 0.72, respectively.

The development of magnetic sorbent for dispersive solid-phase micro-extraction (DmSPE) often requires lengthy multi-step reactions. This research revealed a simplified method for preparing magnetic sorbent for the DmSPE using poly(4-vinylphenol) (PVP). The magnetic sorbent (PVP@MNP) was prepared by coating PVP on magnetic particles (MNP). The characterization and formation of PVP@MNP were confirmed using infrared spectroscopy, scanning electron microscope, and energy-dispersive X-ray spectroscopy. The primary goal of this study is to develop a sensitive DmSPE method to analyze Hg2+ in water using PVP@MNP as a magnetic sorbent. The preparation of PVP@MNP was performed in a simple coating method at room temperature. Briefly, the PVP@MNP was prepared by sonicating the mixture of MNP and PVP. This sorbent was then used as a magnetic sorbent for the extraction of Hg2+ from water. The developed PVP@MNP based DmSPE reached a low method of detection limit (0.01 μg L-1) and limit of quantification (0.04 μg L-1). This method also showed a wide linearity range (100 - 2000 µg L-1) with a good correlation factor under optimized conditions. The developed method showed good recovery (72-90%) with good intraday and interday precision. This study also showed that the developed DmSPE method was effectively used to determine Hg2+ in drinking water, mineral water, and surface water. The result also demonstrated that PVP@MNP is reusable.

Nowadays, breast cancer is considered to be one of the most prevalent diseases worldwide, this initiated interest and growing demand for taxol production in large quantities. The limited availability of traditional taxol production from the Pacific yew trees has encouraged research into the development of taxol production from alternative sources. Thus, the current study aimed to investigate the chemopreventive effect of paclitaxel derived from endophytic fungus Neopestalotiopsis clavispora ASU1. The endophytic fungus Neopestalotiopsis clavispora ASU1(KY624416) showed potent productivity of paclitaxel recording 100.6 µg/l which confirmed by HPLC, LC/Ms-Ms and FTIR analyses. In vitro, the extracted fungal taxol exerted a significant cytotoxic effect (P< 0.05) at 300 nM, revealed that the increase in paclitaxel concentration induces increased cell death. Furthermore, the present study provides a promising approach for coupling paclitaxel production technology by endophytic fungus N. clavispora with chitosan production from residual fungal biomass resulting from taxol extraction and therefore improve the feasibility and commercialization of taxol production. The chitosan yield represented 5.94% of residual fungal dry biomass. Also, fungal chitosan was characterized for the degree of deacetylation (DD) (54.60%), FTIR spectroscopy, reducing power activity (0.263±0.051 mg/ml) may be attributed to hydroxyl groups (OH), and amine groups. These results confirmed that fungi are promising alternative sources for chitosan with superior physiochemical characteristics for food and medical prospective applications.