Mahmoud Berekaa - Academia.edu (original) (raw)

Papers by Mahmoud Berekaa

Karbala international journal of modern science, May 19, 2024

Oxygen activated cold-atmospheric-pressure-argon plasma jet (APPJ) has gained prominence over the... more Oxygen activated cold-atmospheric-pressure-argon plasma jet (APPJ) has gained prominence over the regular argon plasma especially in disinfection and decontamination. As an objective of the current research, an oxygen-enriched argon system was built, where plasma produced through a vessel metallic tube that is introduced into alumina one. A sinusoidal high voltage signal of 25 kHz was used to generate plasma jet. Potential impact of oxygen enriched APP jet (Ar/O 2 ) in decontamination of different microbial cells was observed. For examination, suspension of each tested microbe was placed in contact with plasma jet nearly 10 mm away from the jet nozzle and the lethal effect of activated plasma was evaluated. Results showed that the Ar/O 2 -APP plasma enhanced reactive hydroxyl and other reactive oxygen species generation and hence, antimicrobial activities. For E. coli cells approximately 96.27% and 90.50% reduction in living cell count were recorded after 30 s of exposure to oxygen-activated plasma, on water and LB medium, with a D-value of 36.21 s and 588.24 s, respectively. Also, reduction in S. aureus cells was 92.8% and 96.6% after 30 s, with the D-values of 33.9 s and 181.8 s in water and LB media, respectively. Moreover, C. albicans fungal cells revealed 95% reduction in viable cell count after 10 s. However, the D-value showed only 6.3 s increase due to the impact of organic materials as a component of LB nutritive medium. Generally, the activated argon plasma works effectively even in the presence of organic debris in an exposed medium. Therefore, APPJ can be considered as a prominent straightforward technology for medication of diseases caused by antimicrobial drug-resistant pathogens.

Healthcare

Coronavirus disease 2019, or COVID-19, still has a terrifying potential due to its continuous gen... more Coronavirus disease 2019, or COVID-19, still has a terrifying potential due to its continuous genetic variation. Although vaccines have been created, adherence to preventive measures remains a privileged choice to tackle the pandemic. This study aims to investigate the anxiety, attitudes, and practices (KAPs) towards COVID-19 infection in the Eastern Province of Saudi Arabia. In this cross-sectional study, data were collected from 400 participants via an online self-structured questionnaire. Anxiety, attitude, and practice scores were calculated by summing the points of the statements under the corresponding domain multiplied by 100 over 12, 21, or 15, respectively. Chi-square and one-way analysis of variance were used to investigate the relationships between vaccination, anxiety, attitude, practice scores, and demographic characteristics. More than half of the participants were female (58.5%; mean age of 29.5 years; the majority in the age groups of <20 years and 21–30 years). O...

Atmosphere

High levels of potentially toxic metals and microbes in the atmosphere, especially indoor air, ma... more High levels of potentially toxic metals and microbes in the atmosphere, especially indoor air, may severely threaten human health. Therefore, the concentration and associated health risks of heavy metals (Cd, Cr, Pb, Cu, Fe, Mn, and Zn), biological pollutants, and their risk to human health were assessed using air condition (AC) filter dust samples. Samples were collected from five locations representing agricultural, industrial, and residential settings of the Eastern Province, Kingdom of Saudi Arabia. The levels of trace metals varied considerably among sampling areas, with the highest levels of Cr and Cd recorded in the industrial area sites, followed by the agricultural and residential sites. The highest levels of Pb and Fe were found in the agricultural area sites, followed by the industrial and residential area sites. Among all the metals Cd, Cr, and Pb, showed a considerable health risk through a dermal pathway, and health risks for children from indoor dust exposure were hig...

Gordonia westfalica sp. nov., a novel rubber-degrading actinomycete

How to Cite this Article: Alsubaie ASR, et al. Food Safety in Saudi Arabia: Public Heath Priority... more How to Cite this Article: Alsubaie ASR, et al. Food Safety in Saudi Arabia: Public Heath Priority. Ann Med Health Sci Res. 2020;10: 1142-1147. This is an open access article distributed under the terms of the Creative Com‐ mons Attribution‐NonCommercial‐ShareAlike 3.0 License, which allows others to remix, tweak, and build upon the work non‐commercially, as long as the author is credited and the new creations are licensed under the identical terms. Food Safety in Saudi Arabia: A Public Health Priority Ali Saad R. Alsubaie1 and Mahmoud Mohamed Berekaa2 1Department of Public Health, College of Public Health, Imam Abdulrahman Bin Faisal University, Saudi Arabia; 2Department Environmental Health, College of Public Health, Imam Abdulrahman Bin Faisal University, Saudi Arabia

MicrobiologyOpen, 2018

Twenty‐six different bacterial strains were isolated from samples taken from different locations ... more Twenty‐six different bacterial strains were isolated from samples taken from different locations Dammam, Saudi Arabia, for screening of their polyhydroxyalkanoate (PHA) production capability. The initial screening was conducted by staining with Sudan Black B and Nile Red, followed by examination under fluorescence and electron microscopes to characterize PHA granule formation. The PHA‐producing bacterial isolates were identified using 16S rRNA gene analyses; the most potent bacterial strain was identified as Pseudomonas sp. strain‐P(16). The PHA production capability of this strain in the presence of different low‐cost carbon sources, such as rice bran, dates, and soy molasses, was analyzed. PHA production in the presence of rice bran, dates, and soy molasses was 90.9%, 82.6%, and 91.6%, respectively.

Journal of Environmental Science and Health, Part A, 2003

A feasibility study was conducted to evaluate the efficiency of Pseudomonas fluorescens NS1 bioau... more A feasibility study was conducted to evaluate the efficiency of Pseudomonas fluorescens NS1 bioaugmented to stimulate in situ bioremediation of crude oil-contaminated soil with different amendments in treatment units. Pure culture of P. fluorescens NS1 was isolated from a petroleum-contaminated soil. The rate of degradation of petroleum hydrocarbons by the indigenous soil microflora and in the presence of P. fluorescens

International Journal of Molecular Sciences

Silver Phosphate, Ag3PO4, being a highly capable clinical molecule, an ultrasonic method was empl... more Silver Phosphate, Ag3PO4, being a highly capable clinical molecule, an ultrasonic method was employed to synthesize the M-Ag3PO4, (M = Se, Ag, Ta) nanoparticles which were evaluated for antibacterial and cytotoxicity activities post-characterization. Escherichia coli and Staphylococcus aureus were used for antibacterial testing and the effects of sonication on bacterial growth with sub-MIC values of M-Ag3PO4 nanoparticles were examined. The effect of M-Ag3PO4 nanoparticles on human colorectal carcinoma cells (HCT-116) and human cervical carcinoma cells (HeLa cells) was examined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide) assay and DAPI (4′,6-diamidino-2-phenylindole) staining. Additionally, we analyzed the effect of nanoparticles on normal and non-cancerous human embryonic kidney cells (HEK-293). Ag-Ag3PO4 exhibited enhanced antibacterial activity followed by Ta-Ag3PO4, Ag3PO4, and Se-Ag3PO4 nanoparticles against E. coli. Whereas the order of antibacter...

Nanomaterials

Due to an escalating increase in multiple antibiotic resistance among bacteria, novel nanomateria... more Due to an escalating increase in multiple antibiotic resistance among bacteria, novel nanomaterials with antimicrobial properties are being developed to prevent infectious diseases caused by bacteria that are common in wastewater and the environment. A series of nanolayered structures and nanohybrids were prepared and modified by several methods including an ultrasonic technique, intercalation reactions of fatty acids, and carbon nanotubes, in addition to creating new phases based on zinc and aluminum. The nanomaterials prepared were used against a group of microorganisms, including E. coli, S. aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa. Experimental results revealed that a nanohybrid based on carbon nanotubes and fatty acids showed significant antimicrobial activity against E. coli, and can be implemented in wastewater treatment. Similar behavior was observed for a nanolayered structure which was prepared using ultrasonic waves. For the other microorganisms, a nanolay...

Water

Because of industrial water, many groundwater sources and other water bodies have a strongly acid... more Because of industrial water, many groundwater sources and other water bodies have a strongly acidic medium. Increased bacterial resistance against multiple antibiotics is one of the main challenges for the scientific society, especially those commonly found in wastewater. Special requirements and materials are needed to work with these severe conditions and treat this kind of water. In this trend, nanolayered structures were prepared and modified in different ways to obtain an optimum material for removing different kinds of heavy metals from water in severe conditions, alongside purifying water from a Gram-negative bacteria (E. coli), which is an indication for fecal pollution. An ultrasonic technique effectively achieved this dual target by producing nanolayered structures looking like nanotapes with dimensions of 25 nm. The maximum removal percentages of the heavy metals studied (i.e., iron (Fe), copper (Cu), chromium (Cr), nickel (Ni), and manganese (Mn)) were 85%, 79%, 68%, 63%...

Journal of Environmental and Public Health. Volume 2021, Article ID 6638443, 10 pages, 2021

Background. Lack of knowledge about appropriate handwashing practices has caused great concerns f... more Background. Lack of knowledge about appropriate handwashing practices has caused great concerns for human health, especially in the risk of many communicable diseases. e objective of the current study is to determine the level of handwashing knowledge, attitudes, and practices among school students in Eastern Province Schools, Saudi Arabia. A cross-sectional survey was recruited from November 2019 to March 2020 to assess the level of the students' handwashing knowledge. A reliable questionnaire was prepared (Cronbach's alpha � 0.608) and conducted using a two-stage sampling technique. A total of 271 students participated in the study from primary, middle, and high schools; 80% were boys, most of whom displayed an acceptable level of knowledge on hand hygiene. Nearly 75% and 74% of boys and girls, respectively, gained knowledge about hand hygiene practices from their parents. Only 46% of the students thought that handwashing is a potential protective measure against diseases, whereas 34% thought it only removes dirt. Prevalence of handwashing with soap after using the toilet was recognized among 52% of the students. Additionally, 93% of the students used water and soap to wash their hands (p value < 0.001) and 97% suggested that soap and water are the best methods to wash their hands (p value < 0.001). ere was a positive correlation between the mother's education and hand hygiene practices (p value � 0.044). Results collectively indicated that handwashing knowledge and practices among school students in the Eastern Province are acceptable interventions in preventing the transmission of infectious diseases such as COVID-19. Indeed, further improvement conducted through specific health education programs to emphasize the role of handwashing in health hygiene is highly recommended.

[ Research paper thumbnail of Potential impact of great lockdown on students' knowledge, attitude and practices towards the COVID-19 outbreak [version 1; peer review: 1 approved](https://attachments.academia-assets.com/91831306/thumbnails/1.jpg)

F1000Research, 2022

Background: Despite variation in the types of COVID-19 vaccines and genetic variation in the SARS... more Background: Despite variation in the types of COVID-19 vaccines and genetic variation in the SARS-CoV-2 genome, using preventive measures remains the first choice to reduce risks associated with COVID-19 infection. Methods: This cross-sectional study highlights students' knowledge, attitudes, and practices toward SARS-CoV-2 infection during the lockdown. The study was conducted at the Imam Abdulrahman Bin Faisal University (IAU), Eastern Province, Saudi Arabia. Data was collected from 43 male preparatory students via an online selfstructured questionnaire. Knowledge level was determined using mean scores, while chi-square and t-tests were performed to detect significant differences between groups. Results: Males aged 17-20 displayed better knowledge regarding COVID-19 than other groups (t = 2.03, p = 0.049). Most participants recognized the typical symptoms and transmission routes; 93% indicated they viewed social distancing as a crucial preventive measure. Following lockdown, a 1.7-fold increase in the number of participants who believed that mask-wearing was an effective preventive measure was observed; however, 37.2% did not trust this practice. There was a 2.2-fold increase in the number of participants who took part in awareness programs during lockdown. Students' knowledge increased from 73.2% to 81.5% following the lockdown. Specifically, mean knowledge regarding the role of contaminated tools in disease transmission increased from 33.7% to 75.5%. After lockdown, 58.1% of participants were anxious and afraid of having contact with their colleagues, while 39.5% missed their classes due to anxiety. Two sources of information impacted students' knowledge following the lockdown: university studies (t = 2.149, p = 0.038) and

Among others, road traffic, industrial emissions, commercial activities, smoking and cooking are ... more Among others, road traffic, industrial emissions, commercial activities, smoking and cooking are considered as major contributing factors for the increasing levels of pollutants in atmosphere. High levels of potentially toxic metals and microbes in atmosphere, especially in indoor air, may pose serious threat to human health. Therefore, concentration and associated health risks of potentially toxic trace metals (Cd, Cr, Cu, Fe, Mn, Pb, and Zn) and their risk to human health, and microbial load in indoor air was assessed using air condition (AC) filter dust samples collected from 5 locations representing residential, agricultural and industrial settings of Eastern Province, Kingdom of Saudi Arabia. The levels of trace metals varied considerably among sampling areas, with the highest levels of Cr and Cd recorded in the Industrial-area sites followed by the Agricultural and Urban-Residential sites. The highest levels of Pb and Fe were found in the Agricultural area sites followed by th...

African Journal of Microbiology Research, 2013

Towards an efficient crude oil bioremediation, optimization study of crude oil degradation by Pse... more Towards an efficient crude oil bioremediation, optimization study of crude oil degradation by Pseudomonas sp. strain-O2 was done. Preliminary experiments of crude oil degradation revealed that peptone was the optimal nitrogen source recording 73.3% removal of crude oil, in the presence of 0.5 g/L of yeast extract. The increase of phosphate ratio to 2.5 led to 80.1% removal of crude oil. To evaluate the significance of different culture conditions that affect crude oil biodegradation, Plackett-Burman factorial design was applied. Eleven variables were simultaneously examined. Among those variables, crude oil concentration was the highest positively significant variable that encourage crude oil degradation in Pseudomonas sp. strain-O2 affecting the degradation process, other factors namely, Na-succinate, (NH 4) 2 SO 4 , KH 2 PO 4 and MgSO 4 .7H 2 O showed moderate effect. While, yeast extract, inoculum concentration, agitation, K 2 HPO 4 and NaCl were the lowest significant variables. Fractional factorial design experiments indicated that the pre-optimized medium showed approximately 1.5-folds increase in crude oil degradation by Pseudomonas sp. strain-O2.

International Journal of Biological Chemistry, 2010

Braz J Microbiol, Dec 1, 2009

Research Journal of Microbiology, 2007

Microbial Metal and Metalloid Metabolism

ABSTRACT This publication presents a broad range of current topics and techniques in the exciting... more ABSTRACT This publication presents a broad range of current topics and techniques in the exciting field of environmental biogeochemistry. In addition, it examines emerging developments and applications and forecasts future research directions. This book is divided into three parts: Environments, Processes, and New Technologies. Readers will find a broad range of current topics and approaches in microbe-metal research, including microbial fuel cells, unique microbial physiology, genomics, proteomics, and transcriptomics. All the chapters have been authored by recognized leaders and innovators in the field. Their contributions are based on a thorough review of the current literature and their own first-hand research experience, making the book an ideal reference for investigators interested in the microbial metabolism of metals and metalloids. The book is also recommended as a text for graduate courses in microbial physiology, microbial ecology, and applied and environmental microbiology.

INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY, 2002

A cis-1,4-polyisoprene-degrading bacterium (strain Kb2 T) was isolated from foul water taken from... more A cis-1,4-polyisoprene-degrading bacterium (strain Kb2 T) was isolated from foul water taken from the inside of a deteriorated automobile tyre found on a farmer's field in Westfalia, Germany. The strain was aerobic, Gram-positive, exhibited orange smooth and rough colonies on complex nutrient agar, produced elementary branching hyphae that fragmented into rod/coccus-like elements and showed chemotaxonomic markers which were consistent with its classification within the genus Gordonia, i.e. the presence of mesodiaminopimelic acid, arabinose and galactose in whole-cell hydrolysates (cellwall chemotype IV), N-glycolylmuramic acid in the peptidoglycan wall, a fattyacid pattern composed of unbranched saturated and monounsaturated fatty acids plus tuberculostearic acid, mycolic acids comprising 56-60 carbon atoms and MK-9(H 2) as the only menaquinone. The 16S rDNA sequence of strain Kb2 T was found to be most similar to the 16S rDNA sequences of the type strains of Gordonia alkanivorans (DSM 44369 T) and Gordonia nitida (KCTC 0605BP T). However, DNA-DNA relatedness data showed that strain Kb2 T (l DSM 44215 T l NRRL B-24152 T) could be distinguished from these two species and represented a new species within the genus Gordonia, for which the name Gordonia westfalica is proposed.

Biotechnology(Faisalabad), 2009