Mohammad Alnajjar

Applied Science Private University · Research and graduate studies

Abstract Background: Essential oils extracted from aromatic plants and spices find diverse applications in food preservation, pharmaceuticals, and natural alternatives in healthcare and therapies. This study aimed to evaluate the antibacterial and antibiofilm of Coriander sativum essential oil (CEO) with/without the antibiotic Gentamicin against fo...

E-cigarette use has become increasingly popular, yet its potential impact on mental health, particularly anxiety and hormonal regulation during withdrawal, remains underexplored. CDP-choline, a neuroprotective compound, may offer therapeutic benefits in managing withdrawal symptoms. Hence, chronic exposure to e-cigarettes produces withdrawal-induce...

Aims The gut microbiota plays a key role in host health. An intake of omega-3 and vitamin D3 in a separate manner is vital for maintaining good health of gut microbiota and controlling some illness manifestations. The aim of this study is to investigate the potential change in biodiversity of the gut microbiome in healthy rats supplemented with vit...

Diabetic neuropathic pain is a usual consequence of diabetes. In this study, the formalin-induced pain and the diabetic neuropathy models were used in mice to investigate if the cytidine, uridine, and gabapentin treatments either alone or in combination can reduce nephropathic pain or not. To achieve our goals, cytidine, uridine, and gabapentin, ei...

Background Food supplements such as vitamin D3 and omega-3 have a significant role in activating the immune system and impacting the diversity of gut microbiota; thus, controlling the growth of invading pathogens indirectly. Objective This study aims to evaluate the direct antimicrobial activity of vitamin D3 and omega- 3 individually, combined to...

Probiotics are a mixture of beneficial live bacteria and/or yeasts that naturally exist in our bodies. Recently, numerous studies have focused on the immunostimulatory effects of single-species or killed multi-species probiotic conditioned mediums on macrophages. This study investigates the immunostimulatory effect of commercially available active,...

Honeybees lactic acid probiotics honey quality quantity Background: Honeybees play a pivotal role in the sustainability of ecosystems and biodiversity. Various environmental problems have affected the most significant pollinator, honeybee. Currently , many challenges are facing the honeybee health, and lactic acid-producing bacteria, naturally foun...

Simple Summary Staphylococcus aureus is a prevalent foodborne bacterium causing significant morbidity, mortality, and economic loss, due especially to pathogenic and multidrug-resistant (MDR) strains. This study focused on determining the prevalence of S. aureus in chicken meat in Egyptian markets and assessing the effectiveness of natural phenolic...

Food supplemnts such as vitamin D 3 and omega-3 have a significant impact on controlling pathogens. This study aims to evaluate the antimicrobial activities of combined vitamin D 3 and omega-3 against selected pathogens. Minimum inhibitory activities of different serial dilutions of vitamin D 3 (1.8 µM-216.6 µM) or omega-3 (0.8 mM-110 mM) or combin...

Aerogels, especially bio-based ones, present a promising option for wound dressing; specifically, because of their low toxicity, high stability, bio-compatibility, and good biological performance. In this study, agar aerogel was prepared and evaluated as novel wound dressing material in an in vivo rat study. Agar hydrogel was prepared by thermal ge...

The Arabian Gulf is exposed to intensive dust storms during summer until early winter. We investigated the nutritive effect of the dust on microbial biodiversity of the water column and the productivity of the Gulf. We collected samples from three sites in a transect perpendicular to the shore in March (before the strong dust storms) and in October...

Introduction: Pneumocystis jirovecii is an opportunistic, human-specific fungus that causes Pneumocystis pneumonia (PCP). PCP symptoms are non-specific. A patient with P. jirovecii and another lung infection faces a diagnostic challenge. It may be difficult to determine which of these agents is responsible for the clinical symptoms, preventing eff...

Background: Hepatitis infections, particularly hepatitis B and C, threaten public health to a great extent. They can be directly transferred from pregnant women to their fetuses, either in utero or postpartum. In Saudi Arabia, there is a variation in the prevalence of both infections among women throughout the country’s regions. Thus, it is necessa...

This study aimed to assess the knowledge, practices, and beliefs among the Jordanian population regarding hepatitis B virus (HBV) infection. A cross-sectional questionnaire was designed and used to recruit participants from October 5th through December 12th. Statistical analysis was conducted using SPSS. Descriptive statistical analysis was used to...

In this work, variation in microbiota in the lower respiratory tract (LRT) among asthmatic and non-asthmatic subjects is identified. All participants (27 asthmatic patients and 27 non-asthmatic subjects) were asked to expectorate a sputum sample in special sterile tubes after rinsing the mouth with a sterilizing solution. The expectorated sputum sp...

HBV infection is HBV infection is still a major public health and economic concern worldwide. Therefore, epidemiological studies are still at high concern. There are no epidemiological studies conducted for the prevalence of hepatitis B infection in Ha'il in Saudi Arabia so far. This study aimed to estimate the rate of hepatitis B infection and ide...

Background: Antibiotics are essential for the treatment of bacterial infections and are considered among the most commonly sold drug classes from the community pharmacy in the developing countries without a prescription in most cases. Purpose: This study aims to explore the knowledge, practices, and attitudes regarding antibiotic use. Materials and...

The present study evaluates the effect of calcium alginate aerogel as a potential drug carrier, on the liver and kidney functions, and on the gut microbiota of Wistar rats. The studied alginate aerogel was prepared in the form of nanoparticles using the jet cutting technique, and they were characterized in terms of specific surface areas, outer mor...

This observational study was designed to assess the prevalence, knowledge and attitude of pregnant females towards Hepatitis B infection, in addition to their perspective of the healthcare practice about HBV in Jordan. A randomly selected group of pregnant females visiting public gynecology clinics in Jordan were approached to participate in the st...

PurposeContaminated sites from man-made activities such as old-fashioned tanneries are inhabited by virulent microorganisms that exhibit more resistance against extreme and toxic environmental conditions. We investigated the effect of different Gamma radiation doses on microbial community composition in the sediment of an old-fashioned tannery.Meth...

The Arabian Gulf is exposed to intensive dust storms during summer until early winter. We investigated the nutritive effect of the dust on microbial biodiversity of the water column and the productivity of the Gulf. We collected samples from three sites in a transect perpendicular to the shore in March (before the strong dust storms) and in October...

The human eye is an organ that is exposed to the environment continuously, which makes the ocular surface subjected to different types of pathogenic and non-pathogenic microorganisms. Different types of microorganisms can be found naturally in each layer of the eye, such as the Grampositive bacteria (i.e., the Coagulase-negative staphylococci inclu...

Al Wahbah Crater, located in a remote area in western Saudi Arabia as part of The Harrat extinct volcanic chain, is 2 km wide with a depth of 250 m. It is registered by the General Commission for Tourism and National Heritage as an ancient and archaeological site. The crater is subjected to extreme environmental conditions as its bottom is rarely s...

Desiccated cyanobacterial mats are the dominant biological feature in the Earth’s arid zones. While the response of desiccated cyanobacteria to rehydration is well-documented for terrestrial systems, information about the response in marine systems is lacking. We used high temporal resolution hyperspectral imaging, liquid chromatography, pulse-ampl...

Before the Earth's complete oxygenation (0.58-0.55 Ga ago), the photic zone of the Proterozoic oceans was probably redox stratified and characterized by an upper slightly aerobic nutrient-limited layer above a light-limited layer that tended towards euxinia. In such oceans, cyanobacteria capable of both oxygenic and sulfide-driven anoxygenic photos...

Microbial mats are unique ecosystems that harbor diversified metabolic capabilities raging from photosynthesis in the upper layer to fermentation and organic material degradation accompanied with methane production in the deepest layer. Microorganisms in a microbial mat are successful to flourish in extreme environments because they can shift their...

The Arabian Gulf, surrounded by deserts, is an ideal marine basin to study the effects of nutrient input from dust on primary productivity. We studied the microbial community composition of the water column and sediment using 16S r-RNA gene sequencing, and the activity of photosynthetic microorganisms using pigment analysis and microsensors measure...

We imaged reflectance and variable fluorescence in 25 cyanobacterial mats from four distant sites around the globe to assess, at different scales of resolution, spatial variabilities in the physiological parameters characterizing their photosynthetic capacity, including the absorptivity by chlorophyll a (Achl), maximum quantum yield of photosynthes...

The Um Alhool area in Qatar is a dynamic evaporative ecosystem that receives seawater from below as it is surrounded by sand dunes. We investigated the chemical composition, the microbial activity and biodiversity of the four main layers (L1-L4) in the photosynthetic mats. Chlorophyll a (Chl a) concentration and distribution (measured by HPLC and h...

We describe a novel, field-deployable hyperspectral imaging system, called Hypersub, that allows noninvasive in situ mapping of the microphytobenthos (MPB) biomass distribution with a high spatial (sub-millimeter) and temporal (minutes) resolution over areas of 1 × 1 m. The biomass is derived from a log-transformed and near-infrared corrected refle...

Microbial mats are only present under extreme conditions, where grazing by higher organisms is limited. Therefore, microbial mats may provide insight into extraterrestrial life, due to their adaptations to extreme temperatures, desiccation or salinity. They are faced with a diurnal cycle with variable length based on their location, which exposes t...

The mineralization of organic matter in marine sediments by microbial activity was studied in Umm Alhool sabkha. In intertidal surface sediments, the development of steep compositional and physico-chemical gradients was a common phenomenon. Rapidly, oxygen is consumed within the upper few mm of marine mats and sediments. In permeable sediments, how...

Based on combined microsensor measurements of irradiance, temperature and O2, we compared light energy budgets in photosynthetic microbial mats, with a special focus on the efficiency of light energy conservation by photosynthesis. The euphotic zones in the three studied mats differed in their phototrophic community structure, pigment concentration...

Based on combined microsensor measurements of irradiance, temperature and O(2) , we compared light energy budgets in photosynthetic microbial mats, with a special focus on the efficiency of light energy conservation by photosynthesis. The euphotic zones in the three studied mats differed in their phototrophic community structure, pigment concentrat...

This work presents, the first balanced light energy budget for a benthic microbial mat ecosystem, and shows how the budget and the spatial distribution of the local photosynthetic efficiencies within the euphotic zone depend on the absorbed irradiance (Jabs). It demonstrates the factors affecting variations in light utilization efficiency and invis...

Here we present, to the best of our knowledge, the first balanced light energy budget for a benthic microbial mat ecosystem, and show how the budget and the spatial distribution of the local photosynthetic efficiencies within the euphotic zone depend on the absorbed irradiance (J(abs)). Our approach uses microscale measurements of the rates of heat...

Spectrally resolved imaging was applied to study the growth dynamics of phototrophic biofilms comprizing a mixture of one cyanobacterial and one diatom species. Linear spectral unmixing was combined with liquid chromatography to quantitatively discriminate the areal biomass densities of the two populations. The grown biofilms exhibited highly heter...

Here we describe a spectral imaging system for minimally invasive identification, localization, and relative quantification of pigments in cells and microbial communities. The modularity of the system allows pigment detection on spatial scales ranging from the single-cell level to regions whose areas are several tens of square centimeters. For pigm...

We used microsensors to study short-term temperature effects on gross photosynthesis, oxygen consumption and sulfate reduction in an extremely hypersaline (salinity 200 parts per thousand) cyanobacterial mat. In situ, the mat surface can reach high temperatures (ca. 50 degrees C in summer), and experiences daily temperature fluctuations due to tida...