Abu Bakar Mohd Hilmi

Dr. Abu Bakar Mohd Hilmi

Universiti Sultan Zainal Abidin, Kuala Terengganu, Terengganu, Malaysia

Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

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

Representative Publications

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6 February 2023 in Antibiotics
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MAMohammad A AL-kafaween
Mohammad A AL-kafaween
MAMohammad Alwahsh
Mohammad Alwahsh
AHAbu Bakar Mohd Hilmi
Abu Bakar Mohd Hilmi
DADina Hussain Abulebdah
Dina Hussain Abulebdah
Honey is considered to be a functional food with health-promoting properties. However, its potential health benefits can be affected by individual composition that varies between honey types. Although studies describing the health benefits of Tualang honey (TH), Kelulut honey (KH), and Sidr honey (SH) are scarce, these honey types showed a comparable therapeutic efficacy to Manuka honey (MH). The purpose of this review is to characterise the physicochemical, biological, and therapeutic properties of TH, KH, and SH. Findings showed that these honeys have antibacterial, antifungal, antiviral, antioxidant, antidiabetic, antiobesity, anticancer, anti-inflammatory and wound-healing properties and effects on the cardiovascular system, nervous system, and respiratory system. The physicochemical characteristics of TH, KH, and SH were compared with MH and discussed, and results showed that they have high-quality contents and excellent biological activity sources. Flavonoids and polyphenols, which act as antioxidants, are two main bioactive molecules present in honey. The activity of honey depends on the type of bee, sources of nectar, and the geographic region where the bees are established. In conclusion, TH, KH, and SH could be considered as natural therapeutic agents for various medicinal purposes compared with MH. Therefore, TH, KH, and SH have a great potential to be developed for modern medicinal use.

16 January 2019 in Bulletin of the National Research Centre
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FJFatima Ibrahim Jibril
Fatima Ibrahim Jibril
AHAbu Bakar Mohd Hilmi
Abu Bakar Mohd Hilmi
LMLavaniya Manivannan
Lavaniya Manivannan
Honey is a natural sweetener that is derived from the nectar, pollen, and resin of plants. It has been used as a folk medicine for decades. In addition to being an excellent therapeutic agent, honey possesses an unusually high nutritional content, thus generating interest among researchers. The major phytonutrients of honey are polyphenols. Polyphenols can be separated using high-performance liquid chromatography (HPLC) or liquid chromatography-mass spectrometry (LC-MS). Moreover, to separate the volatile compounds in honey, gas chromatography-mass spectrometry (GC-MS) may be used. Polyphenols have unique and complex structures that are mainly composed of flavonoids and phenolic acids, which confer significant antiviral, anti-inflammatory, antineoplastic, and antiulcer effects and can be used to treat chronic diseases, such as cardiovascular disease. The nature and variability of polyphenols in different honeys posed a challenge to investigations in previous years. Nevertheless, the significant role of honey as a natural therapy and its enrichment with natural substances have led to the continuous discovery of efficient, reliable, and rapid methods for the identification and quantification of novel bioactive compounds in honey. This current review highlights the above mentioned issues.

25 June 2019 in Bulletin of the National Research Centre
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MAMohammad Abdulraheem Al-Kafaween
Mohammad Abdulraheem Al-Kafaween
AHAbu Bakar Mohd Hilmi
Abu Bakar Mohd Hilmi
NJNorzawani Jaffar
Norzawani Jaffar
HAHamid Ali Nagi Al-Jamal
Hamid Ali Nagi Al-Jamal
MZMohd Khairi Zahri
Mohd Khairi Zahri
Pseudomonas aeruginosa and Streptococcus pyogenes are the most common pathogens to humans and are able to form a biofilm following ineffective precautionary approach. Biofilm is defined as a surface-attached community of bacterium embedded in an extracellular matrix which leads to tremendous problems in the environment, among humans and animals. This study aims to investigate the ability of P. aeruginosa and S. pyogenes to form biofilms in 96-well plate before further study in antibiofilm will be done. Initially, the 96-well plate was added with 100 μl of overnight P. aeruginosa culture with optical density (OD) 0.1 and S. pyogenes culture with OD 0.05. The cultures were incubated for 7 days at 37 °C to justify the formation of biofilm. Subsequently, stained blue biofilm was detached from the plate by using 95% ethanol. Biofilms were finally measured using a micro plate reader at 570 nm and were classified based on the adherence strength formula. P. aeruginosa and S. pyogenes biofilms strongly adhered to the plates on days three, four, five and six. Interestingly on day three, biofilms showed the highest formation. However, moderate biofilm formation onto the plates by both P. aeruginosa and S. pyogenes were observed on day two, but non-adherence was observed on days one and seven. Day three is the optimum cultivation period for P. aeruginosa and S. pyogenes to switch into a strong biofilm in microtiter plate and could be beneficial for antibiofilm experiments.

1 January 2021 in Advances and Applications in Bioinformatics and Chemistry
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NSNesrin Seder
Nesrin Seder
AHAbu Bakar Mohd Hilmi
Abu Bakar Mohd Hilmi
WAWalid Aburayyan
Walid Aburayyan
Introduction: Malaysian stingless bee honey (Trigona) has been aroused as a potential antimicrobial compound with antibiofilm activity. The capability of the gram-negative bacillus P. aeruginosa to sustain a fatal infection is encoded in the bacterium genome. Methods: In the current study, a transcriptome investigation was performed to explore the mechanism underlying the biofilm dispersal of P. aeruginosa after the exposure to Trigona honey. Results: Microarray analysis of the Pseudomonas biofilm treated by 20% Trigona honey has revealed a down-regulation of 3478 genes among the 6085 screened genes. Specifically, around 13.5% of the down-regulated genes were biofilm-associated genes. The mapping of the biofilm-associated pathways has shown an ultimate decrease in the expression levels of the D-GMP signaling pathway and diguanylate cyclases (DGCs) genes responsible for c-di-GMP formation. Conclusion: We predominantly report the lowering of c-di-GMP through the down-regulation of DGC genes as the main mechanism of biofilm inhibition by Trigona honey.

1 December 2020
Verified
Journal Article
Open access
MAMohammad Al-Kafaween
Mohammad Al-Kafaween
AHAbu Bakar Mohd Hilmi
Abu Bakar Mohd Hilmi
HAHamid Al-Jamal
Hamid Al-Jamal
NENour Elsahoryi
Nour Elsahoryi
NJNorzawani Jaffar
Norzawani Jaffar
MZMohd Zahri
Mohd Zahri
Background: Honey has been known as a traditional medicine for centuries with its antibacterial properties. It is considered one of the most enduring substances used in wound management. Objectives: This study aimed to: (i) evaluate the effects of Malaysian Trigona honey on bacterial structure and (ii) assess the anti-virulence potential of this honey by examining their impacts on the expression of selected genes (involved in stress survival and biofilm formation) in a test organism. Materials and Methods: Trigona honey's impacts on the bacterial structure (cell morphology) and the expression profiles of select Pseudomonas aeruginosa and Streptococcus pyogenes genes were examined using scanning electron microscopy (SEM) and real-time PCR (RT-qPCR) analysis, respectively. Results: SEM showed that the decreased cell density deformed, disrupted, and damaged cells for both bacteria. RT-qPCR showed that the expression of fleN, fleQ, and fleR genes of P.aeruginosa were decreased, 4.26-fold, 3.80-fold and 2.66-fold respectively. In addition, scpA, ftsY, and emm13 of S.pyogenes were decreased, 2.87-fold. 3.24-fold, and 4.65-fold respectively. Conclusion: Our results indicate that Trigona honey may be an effective inhibitor and virulence modulator of P. aeruginosa and S. pyogenes via multiple molecular targets. This deduction needs to be investigated in vivo.

1 January 2023 in AIMS Microbiology
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MAMohammad Abu-Sini
Mohammad Abu-Sini
MAMohammad A AL-kafaween
Mohammad A AL-kafaween
RARania M. Al-Groom
Rania M. Al-Groom
AHAbu Bakar Mohd Hilmi
Abu Bakar Mohd Hilmi
P. aeruginosa is an opportunistic pathogen that is commonly found in nosocomial infections. The purpose of this study was to investigate the effects of seven antibiotics on P. aeruginosa planktonic growth, biofilm formation, and the expression of virulence factors. These antibiotics included Ciprofloxacin (CP), Amikacin (AMK), Vancomycin (VAN), Tetracycline (TET), Gentamicin (GEN), Erythromycin (Ery), and Clindamycin (CLI). Antibiotic susceptibility testing, Minimum Bactericidal Concentration (MBC), Minimum Inhibitory Concentration (MIC), growth curve, time-kill curve, biofilm inhibition and reduction assay, and RT-qPCR were used to assess the effects of these antibiotics on P. aeruginosa planktonic and biofilm. The clear zones of inhibition against P. aeruginosa for the CP, AMK, VAN, TET, GEN, Ery, and CLI were 26 mm, 20 mm, 21 mm, 22 mm, 20 mm, 25 mm and 23 mm, respectively. The MIC values for CP, AMK, VAN, TET, GEN, Ery and CLI against P. aeruginosa ranged from 0.25 to 1 µg/mL while the MBC values ranged from 1 and 0.5 to 2 µg/mL respectively. The growth, total viable counts (TVCs), bacterial adhesion and biofilm formation of P. aeruginosa were reduced after exposure to all the tested antibiotics in a dose-dependent manner. The RT-qPCR analysis showed that all the tested antibiotics share a similar overall pattern of gene expression, with a trend toward reduced expression of the virulence genes of interest (lasR, lasI, fleN, fleQ and fleR, oprB and oprC) in P. aeruginosa. The results indicate that all of the tested antibiotics possess antimicrobial and anti-biofilm activities, and that they may be multiple inhibitors and moderators of P. aeruginosa virulence via a variety of molecular targets. This deduction requires to be investigated in vivo.