Ali Chokr

Dr. Ali Chokr


Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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29 May 2019 in Toxins
Verified
Journal Article
Open access
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Jean Claude AssafJean Claude Assaf
Jean Claude Assaf
SNSahar Nahle
Sahar Nahle
ACAli Chokr
Ali Chokr
Nicolas LOUKANicolas LOUKA
Nicolas LOUKA
AAAli Atoui
Ali Atoui
Andre EL KHOURYAndre EL KHOURY
Andre EL KHOURY
Aflatoxins (AF) are carcinogenic metabolites produced by different species of Aspergillus which readily colonize crops. AFM1 is secreted in the milk of lactating mammals through the ingestion of feedstuffs contaminated by aflatoxin B1 (AFB1). Therefore, its presence in milk, even in small amounts, presents a real concern for dairy industries and consumers of dairy products. Different strategies can lead to the reduction of AFM1 contamination levels in milk. They include adopting good agricultural practices, decreasing the AFB1 contamination of animal feeds, or using diverse types of adsorbent materials. One of the most effective types of adsorbents used for AFM1 decontamination are those of microbial origin. This review discusses current issues about AFM1 decontamination methods. These methods are based on the use of different bio-adsorbent agents such as bacteria and yeasts to complex AFM1 in milk. Moreover, this review answers some of the raised concerns about the binding stability of the formed AFM1-microbial complex. Thus, the efficiency of the decontamination methods was addressed, and plausible experimental variants were discussed.

1 January 2018 in Brazilian Journal of Microbiology
Verified
Journal Article
Open access
JAJean Claude Assaf
Jean Claude Assaf
AAAli Atoui
Ali Atoui
Andre EL KHOURYAndre EL KHOURY
Andre EL KHOURY
ACAli Chokr
Ali Chokr
Nicolas LOUKANicolas LOUKA
Nicolas LOUKA
Several strains of lactic acid bacteria (LAB), frequently used in food fermentation and preservation, have been reported to bind different types of toxins in liquid media. This study was carried out to investigate the effect of different concentrations of Lactobacillus rhamnosus GG (ATCC 53103) to bind aflatoxin M1 (AFM1) in liquid media. AFM1 binding was tested following repetitive washes or filtration procedures in combination with additional treatments such as heating, pipetting, and centrifugation. The mixture of L. rhamnosus GG and AFM1 was incubated for 18h at 37°C and the binding efficiency was determined by quantifying the unbound AFM1 using HPLC. The stability of the complexes viable bacteria-AFM1 and heat treated bacteria-AFM1 was tested. Depending on the bacterial concentration and procedure used, the percentages of bound AFM1 by L. rhamnosus GG varied from as low as undetectable to as high as 63%. The highest reduction in the level of unbound AFM1 was recorded for the five washes procedure that involved heating and pipetting. Results also showed that binding was partially reversible and AFM1 was released after repeated washes. These findings highlight the effect of different treatments on the binding of AFM1 to L. rhamnosus GG in liquid matrix.

8 December 2025 in Microorganisms
Verified
Journal Article
Open access
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PHPamela Pascal Hindieh
Pamela Pascal Hindieh
JYJoseph Elias YAGHI
Joseph Elias YAGHI
Jean Claude AssafJean Claude Assaf
Jean Claude Assaf
ACAli Chokr
Ali Chokr
AAAli Atoui
Ali Atoui
Andre EL KHOURYAndre EL KHOURY
Andre EL KHOURY
Bacterial biofilms pose significant challenges in clinical, industrial, and environmental settings due to their inherent resistance to antimicrobial agents and host immune responses. Encased within a self-produced extracellular polymeric substance (EPS) matrix, these structured microbial communities demonstrate exceptional resilience, resisting conventional antimicrobial treatments and adapting to, as well as recovering from, environmental and therapeutic stresses, necessitating the development of novel anti-biofilm strategies. This review provides a comprehensive synthesis of biofilm formation, resistance mechanisms, and current and emerging approaches for controlling biofilms, with a primary focus on advancements made over the last decade. Chemical, physical, and biological strategies, including enzymatic degradation, natural compounds, chelating agents, nanoparticles, photodynamic therapy, and probiotics, have demonstrated promising antibiofilm activity. Additionally, combination therapies and targeted drug delivery systems have emerged as viable solutions to enhance the eradication of biofilms. Despite these advancements, challenges such as cytotoxicity, bacterial adaptation, and clinical applicability remain. Addressing these hurdles requires interdisciplinary research to refine existing strategies and develop innovative solutions for effective biofilm management.

1 January 2017 in Journal of Complementary Medicine Research
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Journal Article
Open access
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HKHussein Kanaan
Hussein Kanaan
MEMajid ElMestrah
Majid ElMestrah
ASAlaa Sweidan
Alaa Sweidan
FAFalah Assadi
Falah Assadi
ABAli Bazzal
Ali Bazzal
ACAli Chokr
Ali Chokr
In a search for finding novel therapeutic agents, extracts from an endemic Lebanese plant, Astragalus angulosus, were evaluated for their potential in-vitro antibacterial and antibiofilm activities against three Gram-positive bacterial strains; Staphylococcus epidermidis (CIP444), Staphylococcus aureus (ATCC25923), and Enterococcus faecalis (ATCC29212); in addition to two Gram-negative strains, Escherichia coli (ATCC35218) and Pseudomonas aeruginosa (ATCC27853). The plant was collected in April of 2013 and divided into several different portions, then its extracts were obtained by maceration using two different solvents. Extract analysis followed directly where microtiter broth dilution method was employed to assess antibacterial activity, while antibiofilm potential was tested using colorimetric method. Whole plant ethanolic extract showed the highest bacteriostatic effect at a concentration of 12.78 mg/ml and also was the most versatile exerting its effect against 3 different strains. Other extracts also exhibited an effect but at higher concentrations and each against a single strain. Regarding antibiofilm activity, the majority of the extracts were able to eradicate >50% of S. epidermidis preformed biofilm, where the highest activity was obtained with flower fraction extracted in water, achieving 67.7% biofilm eradication at 0.2 mg/ml. This plant possesses a promising potential in regard to eradicating bacteria and their biofilms and it is the first contributing step of establishing a library for the endemic Lebanese plants in this domain.

21 September 2022 in Plants
Verified
Journal Article
Open access
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MHMariam Hammoud
Mariam Hammoud
ACAli Chokr
Ali Chokr
Hiba N. RAJHAHiba N. RAJHA
Hiba N. RAJHA
CSCarl Safi
Carl Safi
MWMartijn van Walsem
Martijn van Walsem
HRHassan Rammal
Hassan Rammal
(1) Background: Eryngium creticum is a plant medicinally valued, and used in pharmacopeia to treat various diseases. No previous studies have been reported on E. creticum leaf extracts using an IR-assisted technique; thus, this study aimed to intensify polyphenol extraction using Ired-Irrad®, comparing it to the conventional water bath (WB) method. (2) Methods: Optimization of polyphenol extraction from E. creticum leaves was conducted using Response Surface Methodology. Ired-Irrad® was used and compared to the WB method. The biological activities (antiradical, antioxidant, antibacterial, and antibiofilm) of both extracts were assessed. UHPLC analysis was performed to analyze the phytochemical profile of both extracts. (3) Results: Under optimal conditions, IR improved the polyphenol extraction yield by 1.7 times, while lowering ethanol consumption by 1.5 times. Regarding the antibacterial activity, both WB and IR E. creticum leaf extracts exhibited the highest antibacterial activity against Staphylococcus epidermidis. The maximum biofilm prevention capacity was also noticed against S. epidermidis. UHPLC-MS analysis quantified two major phenolic compounds in both extracts: rutin and sinapic acid. (4) Conclusions: Ired-Irrad® technology proved to be an effective technique in intensifying polyphenol recovery, while preserving their quantity and quality.

12 October 2023 in International Microbiology
Verified
Journal Article
Closed access
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SJSuzanne Jonblat
Suzanne Jonblat
FAFalah As-Sadi
Falah As-Sadi
KZKazem Zibara
Kazem Zibara
MSMarwan El Sabban
Marwan El Sabban
VDVera Dermesrobian
Vera Dermesrobian
ACAli Chokr
Ali Chokr