Kamel, S.H., R.F. Al-Jassani and H.A. Al-Shammari. 2022. Effects of Pseudomonas fluorescens, Bacillus thuringiensis tenebrionis Isolates and Biologically Synthesized Silver Nanoparticles on Cellulase Enzyme Activity in Workers' Digestive System of the Termite Microcerotermes diversus Silv. Arab Journal of Plant Protection, 40(4): 315-324. https://doi.org/10.22268/AJPP-40.4.315324 The purpose of this study was to investigate the effect of different bacterial isolates of P. fluorescens and B. t. tenebrionis and silver nanoparticles on the activity of the cellulase enzyme in termites' middle digestive system and its role in glucose release by treating cellulose media with bacterial strains and nanoparticles. Ultraviolet spectroscopy results revealed that silver nanoparticles synthesized by P. fluorescens isolated from termites, commercial P. fluorescens, and local B.t. tenrbrionis had the highest absorption at 385, 324, and 324 nm wave length, respectively. Infrared spectroscopy (FTIR) revealed that ketons, amines, alkanes, and alcohols were among the groups that contributed to silver ions reduction, capping and stabilizing nanoparticles. The particle diameters were measured using a scanning electron microscope (SEM) and found to be on average 32.43, 63.19, and 57.62 nm. The highest concentration of liberated glucose was recorded after 24 hours, which ranged between 0.453 and 1.285 mg/ml when treated with silver nanoparticles prepared from a commercial isolate of P. fluorescens bacteria and when treated with a bacterial isolate P. fluorescens, respectively. Only when treated with synthesized silver nanoparticles and when treated with commercial P. fluorescens isolates did the lowest concentrations of liberated sugar reached between 0.037 and 0.730 mg/ml after 72 hours, respectively. The high quantity of liberated sugar in the control treatment was constant, reaching 1.70 and 2.33 mg/ml after 24 and 72 hours, respectively. In addition to the variation in cellulase enzyme inhibition rates in termite digestive systems due to the effect of different treatments, it was discovered that the local isolate of B. t. tenrbrionis was better than the rest of the isolates in affecting the enzyme, causing inhibition rates of 71.42%. Furthermore, silver nanoparticles synthesized from a commercial isolate of P. fluorescens outperformed other treatments in inhibiting enzyme activity, with an inhibition rate of 78.57% . Keywords: Pseudomonas fluorescens, Bacillus thuringiensis tenebrionis, silver nanoparticles, Microcerotermes diversus
The disposal of textile effluents to the surface water bodies represents the critical issue especially these effluents can have negative impacts on such bodies due to the presence of dyes in their composition. Biological remediation methods like constructed wetlands are more cost-effective and environmental friendly technique in comparison with traditional methods. The ability of vertical subsurface flow constructed wetlands units for treating of simulated wastewater polluted with Congo red dye has been studied in this work. The units were packed with waterworks sludge bed that either be unplanted or planted with Phragmites australis and Typha domingensis. The efficacy of present units was evaluated by monitoring of DO, Temperature, COD
... Show MoreObjectives: The present study aims at detecting the depression among nurses who provide care for infected patients with corona virus phenomenon and to find out relationships between the depression and their demographic characteristics of age, gender, marital status, type of family, education, and years of experience of nurses in heath institutions, infection by corona virus, and their participation in training courses.
Methodology: A descriptive study is established for a period from October 10th, 2020 to April 15th, 2021. The study is conducted on a purposive (non-probability) sample of (100) nurse who are providing care for patients with COVID-19 and they are selected from the isolation wards. The instrument of the study is develope
Free vibration behavior was developed under the ratio of critical buckling temperature of laminated composite thin plates with the general elastic boundary condition. The equations of motion were found based on classical laminated plate theory (CLPT) while the solution functions consists of trigonometric function and a continuous function that is added to guarantee the sufficient smoother of the so-named remaining displacement function at the boundaries, in this research, a modified Fourier series were used, a generalized procedure solution was developed using Ritz method combined with the imaginary spring technique. The influences of many design parameters such as angles of layers, aspect ratio, thickness ratio, and ratio of initial in-
... Show MoreThe approach of green synthesis of bio-sorbent has become simple alternatives to chemical synths as they use for example plant extracts, plus green synthesis outperforms chemical methods because it is environmentally friendly besides has wide applications in environmental remediation. This paper investigates the removal of ciprofloxacin (CIP) using green tea nano zero-valent iron (GT-NZVI) in an aqueous solution. The synthesized GT-NZVI was categorized using SEM, AFM, BET, FTIR, and Zeta potentials techniques. The spherical nanoparticles were found to be nano zero-valent, with an average size of 85 nm and a surface area of 2.19m2/g. The results showed that the removal efficiency of ciprofloxacin depends on the initial pH (2.5-10),
... Show MoreThis study was done to find a cheap, available and ecofriendly materials that can remove eosin y dye from aqueous solutions by adsorption in this study, two adsorbent materials were used, the shells of fresh water clam (Cabicula fluminea) and walnut shells. To make a comparison between the two adsorbents, five experiments were conducted. First, the effects of the contact time, here the nut shell removed the dye quickly, while the C. flumina need more contact time to remove the dye. Second, the effects of adsorbent weight were examined. The nut shell was very promising and for all used adsorbent weight, the R% ranged from 94.87 to 99.29. However C. fluminea was less effective in removing the dye with R% ranged from 47.59 to 55.39. The thi
... Show MoreIn the present study, an attempt has been made to experimentally investigate the flexural performance of ten simply supported reinforced concrete gable roof beams, including solid control specimen (i.e., without openings) and nine beams with web openings of different dimensions and configurations. The nine beams with openings have identical reinforcement details. All beams were monotonically loaded to failure under mid-span loading. The main variables were the number of the created openings, the total area of the created openings, and the inclination angle of the posts between openings. Of interest is the load-carrying capacity, cracking resistance and propagation, deformability, failure mode, and strain development that represent the behav
... Show MoreA new Ni(II) nanostructured chelating system (DHN) was introduced for selective optical heavy-metal ion sensing in an aqueous medium. The cooperative chelating system comprising 8-hydroxyquinoline (8-HQ) and dimethylglyoxime (DMG) has been developed for the first time in association with fibre optic sensing for selective optical heavy-metal ion sensing in an aqueous medium. The Ni(II) nanocompound fluoresces upon 578 nm excitation, showing a highly sensitive optical response with a linear calibration curve in the range 0–100 ng/mL. The regression equation of the calibration curve is y = 0.0035x + 0.9990, which indicates very good linearity, implying R2 = 0.999 with high sensitivity (calibration slope of 0.0035) and low baseline noise (bla
... Show MoreThe aim of this work is to detect the best operating conditions that effect on the removal of Cu2+, Zn2+, and Ni2+ ions from aqueous solution using date pits in the batch adsorption experiments. The results have shown that the Al-zahdi Iraqi date pits demonstrated more efficient at certain values of operating conditions of adsorbent doses of 0.12 g/ml of aqueous solution, adsorption time 72 h, pH solution 5.5 ±0.2, shaking speed 300 rpm, and smallest adsorbent particle size needed for removal of metals. At the same time the particle size of date pits has a little effect on the adsorption at low initial concentration of heavy metals. The adsorption of metals increases with increas
... Show MoreThe simulation of passively Q-switching is four non – linear first order differential equations. The optimization of passively Q-switching simulation was carried out using the constrained Rosenbrock technique. The maximization option in this technique was utilized to the fourth equation as an objective function; the parameters, γa, γc and β as were dealt with as decision variables. A FORTRAN program was written to determine the optimum values of the decision variables through the simulation of the four coupled equations, for ruby laser Q–switched by Dy +2: CaF2.For different Dy +2:CaF2 molecules number, the values of decision variables was predicted using our written program. The relaxation time of Dy +2: CaF2, used with ruby was
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