Publications by authors named "Nejib Guizani"

Fresh produce bacteria may have phenotypic and/or genotypic antimicrobial resistance traits that may lead to various consequences on the environment and human health. This study evaluated the susceptibility of fresh produce bacteria (banana, cabbage, capsicum, carrots, cucumber, dates, lettuce, mango, papaya, pomegranate, radish, tomato and watermelon) to chlorhexidine and the antibiotic resistance of enterococci. Eighty-eight Enterobacteriaceae bacteria and 31 enterococci were screened for their susceptibility to chlorhexidine using the broth microdilution method.

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Enterobacteria may gain antibiotic resistance and be potent pathogens wherever they are present, including in fresh fruits and vegetables. This study tested the antibiotic resistance of enterobacteria isolated from 13 types of local and imported fresh fruits and vegetables ( = 105), using the standard Kirby-Bauer disk diffusion method. Phenotypic and genotypic characterizations of AmpC β-lactamases were determined in cefoxitin-resistant isolates.

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Curcumin has a wide spectrum of biological, pharmaceutical, and antioxidant effects in cancer experimental models. Nitrosamine is commonly used as an experimental oxidizing agent which induces gastric oxidative stress and gastric carcinogenesis in rats. We examined the antioxidant potential effect of curcumin against nitrosamine-induced gastric oxidative stress in rats.

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Folate and vitamin B12 deficiency is associated with depletion of the major intracellular antioxidant glutathione, and oxidative stress is emerging as an etiological mechanism for colon cancer. Azoxymethane (AOM), a potent carcinogen, induces colon cancer in rats by causing pathophysiological changes and oxidative stress. We investigated the synergistic effect of folate and vitamin B12 supplementation against AOM-induced carcinogenesis and oxidative stress in rat colon.

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Oxidative stress plays a pivotal role in the development of diabetes and hyperglycaemia. The protective effects of natural extracts against diabetes are mainly dependent on their antioxidant and hypoglycaemic properties. Broccoli () exerts beneficial health effects in several diseases including diabetes; however, the mechanism has not been elucidated yet.

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Oxidative stress and mitochondrial dysfunction mediated neuro apoptosis is reported to play a major role in the pathology of Parkinson's disease. fruits (ZSCF) are used as traditional medicines that are well-known for their high antioxidant properties. In the present study, we investigated the protective effects of ZSCF extract against 1-methyl-4-phenylpyridinium (MPP) induced neurotoxicity in SH-SY5Y cell lines.

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Background: Date palm has been a major fruit tree in the Middle East over thousands of years, especially in the Arabian Peninsula. Dates are consumed fresh (Rutab) or after partial drying and storage (Tamar) during off-season. The aim of the study was to provide in-depth analysis of fungal communities associated with the skin (outer part) and mesocarp (inner fleshy part) of stored dates (Tamar) of two cultivars (Khenizi and Burny) through the use of Illumina MiSeq sequencing.

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Different microbial groups of the microbiome of fresh produce can have diverse effects on human health. This study was aimed at identifying some microbial communities of fresh produce by analyzing 105 samples of imported fresh fruits and vegetables originated from different countries in the world including local samples (Oman) for aerobic plate count and the counts of Enterobacteriaceae, Enterococcus, and Staphylococcus aureus. The isolated bacteria were identified by molecular (PCR) and biochemical methods (VITEK 2).

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The present study was conducted to assess the status of vitamin C among healthy young adults in relation to serum antioxidant parameters [glutathione (GSH), thiols, and total antioxidant capacity, (TAC)], and oxidative stress markers [malondialdehyde (MDA), and nitrites plus nitrates (NN)]. A prospective study included 200 young adults, and their dietary intake was assessed by using food diaries. Fasting plasma vitamin C, serum levels of GSH, thiols, TAC, MDA, and NN were measured using biochemical assays.

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Aluminum (Al) is an environmental toxin that induces oxidative stress in neuronal cells. Mushroom cultivar extract (MCE) acted as a potent antioxidant agent and protects against cellular oxidative stress in human cultured neuronal cells. This study aimed to investigate the neuroprotective effect of MCE against Al-induced neurotoxicity in rat brain.

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Plants and their by-products offer a diverse mixture of chemical constituents like natural antioxidants. Date- pits are rich in phenolic compounds that have antioxidant potential. The main objective of this study was to investigate the protective effect of a date-pit extract (DPE) against AOM-induced colonic carcinogenicity and oxidative stress.

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The objective of this study was to determine vitamin C stability in fresh and freeze-dried capsicum during storage at different temperatures. Fresh capsicum stored at 20 °C showed an initial decrease in vitamin C with a minimum peak after 2 days and then increased to a maximum peak after 13 days followed by a gradual decay. In general a gradual decrease of vitamin C was observed in the cases of fresh (i.

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This work evaluated the lipid oxidation and the changes in fatty acids in hot-smoked tuna (Thunnus albacares) as a function of brine concentration. Fresh, commercially harvested tuna fish samples were purchased from a local supermarket. The fish were first immersed for 30 min in a brine solution at 5, 10, or 15% sodium chloride concentration and were then smoked at 50 °C for 3 h followed by 1 h at 60 °C and 3 h at 105 °C.

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The effect of frozen storage on the physiochemical, chemical and microbial characteristics of two types of fish sausages was studied. Fish sausages developed (DFS) with a spice-sugar formulation and commercial fish sausages (CFS) were stored at -20 °C for 3 months. Fresh DFS contained 12.

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Hydrogen peroxide is an oxidative stress agent that is associated with depletion of intracellular glutathione and inhibition of antioxidant enzymes in different cell lines. Consumption of antioxidant-rich foods reduces cellular oxidative stress and its related health problems. This study aimed to assess the antioxidant properties of mushroom, Agaricus bisporous cultivar extract, against hydrogen peroxide induced oxidative stress in cultured human hepatic (HepG2) and neuronal (SH-SY5Y) cells.

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Zizyphus spina-christi (ZSC) fruit is a rich source of bioactive compounds but any medicinal properties in chemoprevention of colon cancer have hitherto not been studied. The aim of the present study was to examine in vivo protective effects of ZSC water extract on colon carcinogenesis in azoxymethane (AOM)-treated rats. Our results showed that ZSC significantly reduced AOM-induced colonic aberrant crypt foci development and AOM-induced oxidative stress as indicated by restoration of endogenous glutathione depletion and abrogating the impairment of total antioxidant capacity.

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Functional foods include antioxidant nutrients which may protect against many human chronic diseases by combating reactive oxygen species (ROS) generation. The purpose of the present study was to investigate the protective effect of pomegranate peel extract (PPE) on azoxymethane (AOM)-induced colon tumors in rats as an in vivo experimental model. Forty Sprague-Dawley rats (4 weeks old) were randomly divided into 4 groups containing 10 rats per group, and were treated with either AOM, PPE, or PPE plus AOM or injected with 0.

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In a previous study, we demonstrated the ability of papaya epicarp extract (PEE) to protect against oxidative stress-induced insult in human SH-SY5Y neuronal cells in a mechanism that appeared to be by means of PEE potent antioxidant properties. To further understand this relationship, we examined the effect of PEE intervention on aluminum (Al)-induced cytotoxicity in SH-SY5Y cells. The results indicated that PEE was effective in protecting against Al-induced cell death in a dose-dependent manner.

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The present study evaluated the antioxidant (AA), antimicrobial and preservation effects of five plant derived natural products viz., Rosmarinic Acid (RA), p-Coumaric Acid (pCA), Trans-Cinnamic Acid (TCA), Hydroxyphenyllactic Acid (HPA) and Caffeic acid (CA) along with synthetic compounds (Ascorbic acid, gallic acid, citric acid and BHA) on fresh cut apple slices. Antimicrobial efficacy of these compounds against Bacillus licheniformis, Pseudomonas vulgaris, Shigella boydii, Salmonella typhi, Staphylococcus aureus, Listeria monocytogenes and Escherichia coli was found to be concentration dependent with the maximum inhibition observed at 500 microg mL(-1).

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Recent studies indicated that regular consumption of antioxidant-rich foods reduces cellular oxidative stress and protects against health-related problems. This study aimed to assess the in vitro antioxidant properties of the papaya epicarp extract against hydrogen peroxide (H(2)O(2))-induced oxidative stress in human SH-SY5Y neuronal cells. Our study revealed that papaya epicarp extract acted as a potent free radical scavenger and provided neuroprotection against H(2)O(2)-induced oxidative stress.

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Glass transition and other thermal characteristics of gelatin from different sources were studied by differential scanning calorimetry (DSC) and modulated DSC (MDSC). The initial glass transition temperatures of equilibrated gelatin samples at 11.3% relative humidity, determined from reversible heat flow thermogram of MDSC, were 23, 75 and 59°C, respectively, for tuna skin, bovine and porcine gelatin.

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