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
Orthodontic tooth movement is characterized by tissue reactions, which consist of an inflammatory response in periodontal ligament and followed by bone remodeling in the periodontium depending on the forces applied. These processes trigger the secretion of various proteins and enzymes into the saliva. The purpose of this study was to evaluate the activity of the lactate dehydrogenase (LDH) in saliva during orthodontic tooth movement using different magnitude of continuous orthodontic forces. Thirty orthodontic patients (12 males and 18 females) with ages 17-23 years with class II division I malocclusion all requiring bilateral maxillary first premolar extractions. Those patients were randomly divided into 3 groups according to the magnitude
... Show MoreRation power plants, to generate power, have become common worldwide. One such one is the steam power plant. In such plants, various moving parts of heavy machines generate a lot of noise. Operators are subjected to high levels of noise. High noise level exposure leads to psychological as well physiological problems; different kinds of ill effects. It results in deteriorated work efficiency, although the exact nature of work performance is still unknown. To predict work efficiency deterioration, neuro-fuzzy tools are being used in research. It has been established that a neuro-fuzzy computing system helps in identification and analysis of fuzzy models. The last decade has seen substantial growth in development of various neuro-fuzzy systems
... Show MoreAbstract Background: The daily usage of maxillofacial prostheses causes them to mechanically deteriorate with time. This study was aimed to evaluate the reinforcement of VST50F maxillofacial silicone by using yttrium oxide (Y2O3) nanoparticles (NPs) to resist aging and mechanical deterioration. Materials and Method: Y2O3 NPs (30–45nm) were loaded into VST50F maxillofacial silicone in two weight percentages (1 and 1.5 wt%), which were predetermined in a pilot study as the best rates for improving tear strength with minimum increase in hardness values. A total of 120 specimens were prepared and divided into the control and experimental groups (with 1 and 1.5 wt% Y2O3 addition). Each group included 40 specimens, 10 specimens for each paramet
... Show MoreBackground: The emergence and spread of multidrug-resistant Gram-negative bacilliin burn wound infections related to biofilm formation, which lend to challenge in treatment with conventional antibiotics andprompting to search for novel antimicrobial agents to control the infections.Silver nanoparticles (AgNPs) have wide spectrum biological properties with different mechanisms of action and less toxicity towards human cells.
Objective:The goal of this study was to evaluated the anti-bacterial and anti-biofilm activities of AgNPs alone and in combination with aminoglycoside (Amikacin) and β-lactam (Ampicillin) antibiotics against multidrug resistant Gram-negative bacilli (Pseudomonas aeruginos
... Show MoreBackground: Suppression of quorum sensing (QS) that regulates many virulence factors, including antimicrobial resistance, in bacteria may subject the pathogenic microbes to the harmful consequences of the antibiotics, increasing their susceptibility to such drugs. Aim: The current study aimed to make an aqueous crude extract from the soil Proteus mirabilis isolate with the use of the gas chromatography-mass spectrometry (GC-MS) technique for its analysis, and then, study the impact of the extract on clinical isolates of Pseudomonas aeruginosa. Methods: Preparation of crude extracts from P. mirabilis (both organic and aqueous), which were then analyzed by GC-MS to detect the bioactive ingredients. Furthermore, the extract’s capability to i
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