Nowadays, there is increased interest in the biosynthesis of microbial melanin related to their numerous biological functions and applications in many fields, especially in medical fields, including immune-modulating, antimicrobial antibiotic, antiviral antivenin, anticancer, antitumor activity, and anti-biofilm activity. Pyomelanin is a hydrophobic macromolecule that is typically dark brown or black in color, formed by the oxidative polymerization of phenolic or indolic compounds. Pyomelanin is reported to be safe for consumption, thus providing a crucial strategy for biocontrol of biofilm. Furthermore, natural pyomelanin is known as a potent antioxidant, photoprotective, and free radical scavenging. Objective: This study focuses on the extraction and parametric optimization of melanin using Pseudomonas aeruginosa (P. aeruginosa) isolates. Materials and Methods: P. aeruginosa was isolated from various clinical sources, including urinary tract infections, burn patients, and wound infections. The isolate’s identification was done by biochemical, cultural, and VITEK-2 compact system. The isolates were subjected to pyomelanin production in nutrient agar supplemented with L-tyrosine, and the potential isolate was selected and employed for melanin production using nutrient broth supplemented with L-tyrosine. The pyomelanin-producing isolates were further identified through the PCR analysis technique. Different physical parameters were used for optimum pyomelanin yield. Results: The potential P. aeruginosa isolates were further identified using 16s rRNA. Pyomelanin production was better at 2.9 µg/mL at 100 rpm. The highest pyomelanin production was 3.07 µg/mL after 72 h incubation. The optimum pH at 7 was 3.12 µg/mL. The highest pyomelanin yield at 40°C was 3.03 µg/mL, while the maximum pyomelanin was produced using 2 g/L tyrosine at 2.99 µg/mL. UV-visible (UV-Vis) spectroscopy analysis for pyomelanin pigment was at 273.5 nm. The infrared spectrum exhibited a broad absorption band around 3280.82 cm−1 which corresponds to the presence of -OH and N-H groups. Conclusion: This study provides knowledge on factors affecting pyomelanin production using bacteria in broth media supplemented with L-tyrosine.
This study was designed to evaluate the effect of aqueous extract of Arabidopsis thaliana seeds on reducing glucose level for white albino mice. Twenty adults mice were used, divided randomly into four groups (five mice per each group). The first group (normal mice) was administrated with 0.1 ml of distilled water as a control, the second group (normal mice) was administrated with 0.1 ml of the plant extract, whereas the third and fourth groups (diabetic mice) were administrated with single dose of alloxan (150 mg/kg of the body weight) to induce diabetes, and the fourth group was administrated with 0.1 ml of the plant extract for 10 days, then blood glucose level was measured for all of the experimental animals (diabetic and no
... Show MoreThis study addressed the work stress sources and level of the communicator in public relations in governmental institutions in the United Arab Emirates. The importance of this study is the lack of studies on work stress of the communicator in public relations. The study aimed to investigate the work stress source Physical, individual, groups, organizational and Professional source which effect on the performance of communicator in public relations. The researcher used the descriptive approach and questionnaire as an essential tool for collecting information. Some of the important results of the study are The communicator in public relations facing stress in work by 42% which affect on his performance by average level. The organizational
... Show MoreThe current study was conductedas a pot experiment to determine the effect of soil texture on biological nitrogen fixation (BNF) of six most efficient local isolates, specified, of Bradyrhizobium. Cowpea (Vignaunguiculata L.), as a legume host crop, was used as a host crop and 15N dilution analysis was used for accurate determination of the amount of N biologically fixed under experimental parameters specified. Soils used are clay loam, sandy clay loam and sandy loam. Biological Nitrogen Fixation (BNF), in different soil textural classes, was as in the following order: medium texture soil > heavy texture soil > light textured soil. Statistical analysis showed that there is a significant variation in BNF % among six Iraqi isolates in the th
... Show MoreNanostructured Al2O3has been applied as a protective coating against corrosion of the carbon steel (C.S) in seawater environment (3.5% NaCl) at temperatures range (298-328)K. Aluminananoparticles were deposited on carbon steel substrates by cathodic electrophoretic deposition (EPD) with ethanol as suspension medium and poly(acrylic acid) (PAA) as polymeric charging agent. Meanwhile, thesurface morphology was examined using Atomic-force microscopy (AFM). The cross-section AFM showed that the particles sizes for the Al2O3 NPs is around 60-80 nm. The anticorrosion behaviour of coated C.S was investigated in 3.5% NaCl at temperature range 298-328 K by potentiodynamic polarization measurements. Results show that using PAA in suspension coat incr
... Show MoreThe study aimed to spread the culture of efficient performance between nursing staffs, which would contribute and achieve health care quality, and to clarify the role of nursing in improving the quality of high-quality health care, as well as to clarify how to reach national standards for the quality of health care in Iraq, Therefore, the study dealt with the efficiency of nursing performance as an explanatory variable, and the quality of health care as a dependent variable. The fact that the health sector is the foundation for building a healthy society free from diseases, so hospital of IBN AL-NAFIS as an institution and it's nursing teams were taken as a community for this study. The results to be objective and reflect the rea
... Show MoreExtract from cell culture of medicinal plant like Nigella sativa have been assessed for its cytotoxic properties. Thymol is likely responsible for the theraputic effects of Nigella sativa leaf callus extract. In this short study the inhibitory effect of Nigella sativa leaf callus extract (Thymol) has been studied on Human Lorgnx Epidrmoid Carcinoma (Hep-2) cell line during different exposure period of time (24, 48 and 72 hrs.) using different concentration of the extract (1000, 500, 400, 300, 200 and 100 µg/ml). The optical density of the Hep-2 cells has been readed on 492 nm wave length. Thymol –induced cytotoxicity was (500 µg/ml) which inhibit cell growing compared to the control and this
... Show MoreSheet piles are necessary with hydraulic structures as seepage cut-off to reduce the seepage. In this research, the computational work methodology was followed by building a numerical model using Geo-Studio program to check the efficiency of using concrete sheet piles as a cut-off or reducer for seepage with time if the sheet piles facing the drawdown technique. Al-Kifil regulator was chosen as a case study, an accurate model was built with a help of observed reading of the measuring devices, which was satisfactory and helped in checking the sheet piles efficiency. Through the study, three scenarios were adopted (with and without) drawdown technique, it was found that at the short time there's no effect of the drawdown technique on
... Show MoreThe utilization of targeted therapy for programmed death ligand 1 (PD‑L1) has emerged as a prominent focus in contemporary clinical trials, particularly in the context of immune checkpoint inhibitors. The prognostic significance of the expression of PD‑L1 in invasive mammary cancer remains a subject of discussion in clinical oncology, requiring further exploration, despite its recognition as a biomarker for responsiveness to anti‑PDL1 immunotherapy. The present study was conducted to investigate the immunohistological expression of PD‑L1 in women with triple‑negative breast cancer (TNBC), with a particular focus for searching for the associated clinical and pathological characteristics. The present retrospective study examined the
... Show MoreIn this study, the flexural performance of a new composite beam–slab system filled with concrete material was investigated, where this system was mainly prepared from lightweight cold-formed steel sections of a beam and a deck slab for carrying heavy floor loads as another concept of a conventional composite system with a lower cost impact. For this purpose, seven samples of a profile steel sheet–dry board deck slab (PSSDB/PDS) carried by a steel cold-formed C-purlins beam (CB) were prepared and named “composite CBPDS specimen”, which were tested under a static bending load. Specifically, the effects of the profile steel sheet (PSS) direction (parallel or perpendicular to the span of the specimen) using different C-purlins c
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