Chun Wie Chong

Monash University (Malaysia) · School of Pharmacy

Objectives: Gut microbiome alterations in Parkinson's disease (PD) have been reported repeatedly, but their functional relevance remains unclear. Fecal metabolomics, which provide a functional readout of microbial activity, have scarcely been investigated. We investigated fecal microbiome and metabolome alterations in PD, and their clinical relevan...

Objective: While some oral carcinomas appear to arise de novo, others develop within long-standing conditions of the oral cavity that have malignant potential, now known as oral potentially malignant disorders (OPMDs). The oral bacteriome associated with OPMD has been studied to a lesser extent than that associated with oral cancer. To characterize...

No studies have investigated the influence of ethnicity in a multi-ethnic middle-income country with a long-standing history of co-habitation. Stool samples from 214 Malaysian community members (46 Malay, 65 Chinese, 49 Indian, and 54 Jakun) were collected. The gut microbiota of the participants was investigated using 16S amplicon sequencing. Ethni...

Ethnicity is consistently reported as a strong determinant of human gut microbiota. However, the bulk of these studies are from Western countries, where microbiota variations are mainly driven by relatively recent migration events. Malaysia is a multicultural society, but differences in gut microbiota persist across ethnicities. We hypothesized tha...

Background Gut microbiome alterations have been reported in Parkinson's disease (PD), but with heterogenous findings, likely due to differences in study methodology and population. We investigated the main microbiome alterations in PD, their correlations with disease severity, and the impact of study and geographical differences. Methods After sys...

Weedy rice is a major problem in paddy fields around the world. It is well known that weedy rice appears to grow faster and mature earlier than cultivated rice. It is possible that differences in the root microbial genetics are correlated with this characteristic. This study incorporated 16S rRNA amplicon sequencing to study the microbial compositi...

Klebsiella pneumoniae is a Gram-negative Enterobacteriaceae that is classified by the World Health Organisation (WHO) as a Priority One ESKAPE pathogen. South and Southeast Asian countries are regions where both healthcare associated infections (HAI) and community acquired infections (CAI) due to extended-spectrum β-lactamase (ESBL)-producing and c...

Previous studies on probiotics in chickens have shown varying efficacy, and the use of phage as a supplement for improving chicken performance and health has gained interest. However, the combination of these supplements has not been thoroughly investigated. This study aimed to assess the effects of an Escherichia coli phage cocktail, both alone an...

Background: S. pneumoniae (SPN) is the most common cause of pneumonia. The disease can be effectively prevented through immunisation. Since December 2020, the Malaysian Government has included the 10-valent pneumococcal conjugate vaccine (PCV10) for all infants born on or after 1 January 2020 as part of the National Immunisation Programme (NIP). Ho...

Background The high burden of extended-spectrum beta-lactamase-producing (ESBL)-producing Enterobacterales worldwide, especially in the densely populated South East Asia poses a significant threat to the global transmission of antibiotic resistance. Molecular surveillance of ESBL-producing pathogens in this region is vital for understanding the loc...

Background While oral mirobial dysbiosis due to tobacco smoking has been studied thoroughly, there is limited data on the effect of waterpipe smoking on the oral microbiome. This study aims to compare the salivary microbiome between waterpipe smokers and non-smokers. Materials and methods Unstimulated saliva samples were collected from 60 particip...

Background: Adequate calcium intake at an early age is crucial to achieving peak bone mass. Nevertheless, low calcium intake is common in Malaysian children. Aim: This study examined the calcium food sources and factors associated with low calcium intake among 243 children aged 9–11 years in Kuala Lumpur. Methods: Diet histories and bone density we...

Medication adherence profoundly affects blood glucose management in patients with type 2 diabetes. Measures to contain the COVID-19 pandemic have affected disease management and medication adherence, owing to limited access to healthcare facilities. This study aimed to examine the impact of the COVID-19 lockdown on adherence to glucose-lowering and...

(1) Background: Antibiotic resistance is a serious health issue, and raising public awareness of it is crucial to combating it. This study aimed to assess the socio-demographic factors associated with knowledge of antibiotics and antibiotic resistance in Malaysia. (2) Methods: A cross-sectional study was carried out between April 2022 and March 202...

The prevalence of antibiotic-resistant bacteria in Southeast Asia is a significant concern, yet there is limited research on the gut resistome and its correlation with lifestyle and environmental factors in the region. This study aimed to profile the gut resistome of 200 individuals in Malaysia using shotgun metagenomic sequencing and investigate i...

Objectives: This study aims to evaluate the cost-effectiveness of various glucose-lowering therapies as add-on to standard care for people with type 2 diabetes (T2D) in Malaysia. Methods: A state-transition microsimulation model was developed to compare the clinical and economic outcomes of 4 treatments: standard care, dipeptidyl peptidase-4 inh...

Objectives Data on the long-term effects comparing sodium-glucose co-transporter 2 inhibitors (SGLT2i) and dipeptidyl peptidase-4 inhibitors (DPP4i) are scarce, especially from middle-income countries. To examine the effects of SGLT2i and DPP4i on the cardiorenal function and treatment adherence for people with type 2 diabetes (T2D) using prevalent...

Phages, which are often used therapeutically, have begun to receive interest as alternatives to antibiotic growth promoters (AGPs) for enhancing chicken growth. Another option that has been extensively studied as a growth promoter in chickens is probiotics. To the best of our knowledge, there is currently no study available on the use of phages and...

Background Plant-based diets offer more beneficial microbes and can modulate gut microbiomes to improve human health. We evaluated the effects of the plant-based OsomeFood Clean Label meal range (‘AWE’ diet), on the human gut microbiome. Methods Over 21 days, ten healthy participants consumed OsomeFood meals for five consecutive weekday lunches an...

Caffeine, trigonelline, nicotinamide, and hippuric acid are potential organic markers of anthropogenic activities in the environment. In this work, a selective, precise, accurate, and robust reverse phase high performance liquid chromatography with a diode array detection method was developed for their simultaneous determination. Chromatographic an...

Kombucha is a fermented tea known for its health-enhancing properties owing to the bioactive compounds generated by acetic acid bacteria (AAB) and lactic acid bacteria (LAB). We compared the distribution of AAB and LAB across nine kombucha products in Singapore (Product A to I) using shotgun metagenomics. High prevalence of Komagataeibacter species...

Background: The gut microbiota in irritable bowel syndrome (IBS) is known to vary with diet. Aims: i) To analyse the gut microbiota composition of IBS patients from a multi-ethnic population and ii) explore the impact of a low FODMAP diet on gastrointestinal symptoms and gut microbiota composition amongst IBS patients. Methods: A multi-centre...

The prevalence of pre-diabetes is increasing globally, affecting an estimated 552 million people by 2030. While lifestyle interventions are the first line of defense against progression toward diabetes, information on barriers toward pre-diabetes management and how to overcome these barriers are scarce. This systematic review describes the publics’...

Phage, which is often used therapeutically, has begun to receive interest as an alternative to antibiotic growth promoters (AGPs) to enhance chicken growth. Another option that has been extensively studied as a growth promoter in chicken is probiotics. However, there are no studies using phages and probiotics as prospective feed additives for broil...

The understanding of yield responses of different oil palm progenies to rainfall is important for plantation management to ensure that the most suitable progeny is selected for maximum productivity. Drought responses are commonly studied using drought induction on oil palm seedlings or by conducting irrigation trials. Nevertheless, such trials may...

Background Diabetes is one of the leading cause of chronic kidney disease (CKD) and end stage renal disease. This study aims to develop and validate different risk predictive models for incident CKD and CKD progression in people with type 2 diabetes (T2D). Methods We reviewed a cohort of people with T2D seeking care from two tertiary hospitals in...

Non-carbapenemase-producing carbapenem-resistant Klebsiella pneumoniae (NC-CRKP) confers carbapenem resistance through a combination of chromosomal mutations and acquired non-carbapenemase resistance mechanisms. In this study, we aimed to evaluate the clinical and molecular profiles of NC-CRKP isolated from patients in a tertiary teaching hospital...

Kombucha is a fermented tea drink traditionally known for its health-enhancing properties owing to the bioactive compounds generated by acetic acid bacteria (AAB) and lactic acid bacteria (LAB). In this study, we compared the distribution of AAB and LAB species and the contributing functional pathways across nine commercial kombucha products in Sin...

Altered gut microbiota composition has been observed in individuals with hidradenitis suppurutiva (HS) and many other inflammatory diseases, including obesity, type 1 and type 2 diabetes. Here we addressed whether Adalimumab, a systemic anti‐inflammatory therapy, may impact the microbiota biochemical profile, particularly on beneficial metabolites...

Staphylococcus aureus expresses diverse proteins at different stages of growth. The immunodominant staphylococcal antigen A (IsaA) is one of the proteins that is constitutively produced by S. aureus during colonisation and infection. SACOL2584 (or isaA) is the gene that encodes this protein. It has been suggested that IsaA can hydrolyse cell walls,...

Geraniin, an ellagitannin, has ameliorative properties against high-fat diet (HFD)-induced metabolic syndrome. Since geraniin has poor bioavailability, we hypothesised the interaction of this compound with gut microbiota as the main mechanism for improving metabolic aberrations. Male Sprague Dawley rats were divided into normal diet (ND)- and HFD-f...

Objectives This study profiled the prevalence of extended-spectrum ß-lactamase-producing Escherichia coli (ESBL-EC) in the community and compared their resistome and genomic profiles with isolates from clinical patients through whole-genome sequencing. Methods Fecal samples from 233 community dwellers from Segamat, a town in southern Malaysia, wer...

Inappropriate use of antibiotics has been shown to contribute to the occurrence of multidrug-resistant organisms (MROs). A surveillance study was performed in the largest tertiary care hospital in Kuala Lumpur, Malaysia, from 2018 to 2020 to observe the trends of broad-spectrum antibiotics (beta-lactam/beta-lactamases inhibitors (BL/BLI), extended-...

Background Carbapenem resistant Enterobacteriaceae (CRE) has rapidly disseminated worldwide and has become a global threat to the healthcare system due to its resistance towards “last line” antibiotics. This study aimed to investigate the prevalence of CRE and the resistance mechanism as well as the risk factors associated with in-hospital mortalit...

Introduction Smoked, and especially smokeless, tobacco are major causes of oral cancer globally. Here, we examine the oral bacteriome of smokers and of smokeless tobacco users, in comparison to healthy controls, using 16S rRNA gene sequencing. Methods Oral swab samples were collected from smokers, smokeless tobacco users, and healthy controls (n =...

Aims To compare the cardiovascular, renal and safety outcomes of second-line glucose-lowering agents used in the management of people with type 2 diabetes. Methods MEDLINE, EMBASE, and CENTRAL were searched from inception to 13th July 2021 for randomised controlled trials comparing second-line glucose lowering therapies with placebo, standard care...

Objective: Converging evidence suggests that intestinal inflammation is involved in the pathogenesis of neurodegenerative diseases. Previous studies on fecal calprotectin in Parkinson's disease (PD) were limited by small sample sizes, and literature regarding intestinal inflammation in multiple system atrophy (MSA) is very scarce. We investigated...

Burkholderia pseudomallei ( B . pseudomallei ) is an intracellular pathogen that causes melioidosis, a life-threatening infection in humans. The bacterium is able to form small colony variants (SCVs) as part of the adaptive features in response to environmental stress. In this study, we characterize the genomic characteristics, antimicrobial resist...

The rise of antimicrobial resistance (AMR) among clinically important bacteria, including respiratory pathogens, is a growing concern for public health worldwide. Common causative bacteria for upper respiratory tract infections (URTIs) include Streptococcus pneumoniae and Haemophilus influenzae, and sometimes Staphylococcus aureus. We assessed the...

The emergence of carbapenem-resistant Acinetobacter baumannii (CRAB) has now become a global sentinel event. CRAB infections often instigate severe clinical complications and are potentially fatal, especially for debilitated patients. The present study aimed to conduct molecular characterization on CRAB isolated from patients in the intensive care...

Background The impact of non-dietary lifestyle factors on the gut microbiota, such as physical activity, has not been frequently reported. Recent studies have suggested that exercise can increase the number of beneficial microbial species which enhance short-chain fatty acid synthesis and carbohydrate metabolism. Therefore, we investigated the rela...

Background The gut microbiome plays an instrumental role in cardiovascular, metabolic and gastrointestinal health (Valdes et al. 2018). In Traditional Chinese Medicine (TCM) , one’s health status can be described by nine body constitutions (BCs) which are broadly classified as ‘Neutral’, indicating optimal health, or ‘Unbalanced’, indicating subop...

Background Singapore and Malaysia are neighbouring countries with similar ethnic make-up: Chinese, Indian, and Malays. However, Singapore is a high-income economy while Malaysia is a middle-income economy. Such a difference has resulted in some levels of dichotomy in diet and lifestyles. In this study, we sought to investigate the gut-ethnic variat...

Background Psychological stress, which is associated with poor sleep quality, has a profound effect on the gut microbiome. To better elucidate the gut microbiome changes associated with psychological stress, we measured levels of stress and sleep quality among the healthy stool donors recruited through a national campaign, and further assessed thei...

Obesity is a driving factor in the onset of metabolic disorders. This study aims to investigate the effects of the myricetin derivative-rich fraction (MD) from Syzygium malaccense leaf extract on high-fat diet (HFD)-induced obesity and its associated complications and its influence on uncoupling protein-1 (UCP-1) and gut microbiota in C57BL/6J mice...

Antibiotic resistance is a major global health issue that has seen alarming rates of increase in all parts of the world over the past two decades. The surge in antibiotic resistance has resulted in longer hospital stays, higher medical costs, and elevated mortality rates. Constant attempts have been made to discover newer and more effective antimic...

Introduction Pneumonia is a leading cause of death in Malaysia. Whilst many studies have reported the aetiology of pneumonia in Western countries, the epidemiology of pneumonia in Malaysia remains poorly understood. As carriage is a prerequisite for disease, we sought to improve our understanding of the carriage and antimicrobial resistance (AMR) o...

Background Knowledge on the epidemiology, genotypic and phenotypic features of antimicrobial-resistant (AMR) ESKAPEE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp., and Escherichia coli) and their association with hospital-acquired infections (HAIs) a...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Background: Hypermucoviscous carbapenem-resistant Klebsiella pneumoniae (hmCRKp) is emerging globally and approaching the worst-case scenario in health care system. Aims: The main objective in this study was to determine the hypermucoviscous characteristics among the carbapenem-resistant K. pneumoniae (CRKp) isolated from a teaching hospital in Ma...

BACKGROUND Prediabetes, where an individual’s glycaemic variables are significantly higher than normal but lower than the threshold for diabetes, is a major health problem. People with prediabetes experience a higher risk of developing chronic kidney disease, neuropathy, diabetic retinopathy, cardiac events, and stroke. The implementation of lifest...

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) is a great concern, as carbapenems are the last-line therapy for multidrug-resistant Gram-negative bacteria infections. This study aims to report the epidemiology of CRKP in a teaching hospital in Malaysia based on the molecular genotypic and clinical characteristics of the isolates...

Diseases caused by typhoidal and non-typhoidal Salmonella remain a considerable threat to both developed and developing countries. Based on the clinical symptoms and serological tests, it is sometimes difficult to differentiate the Salmonella enterica serovar Paratyphi A (S. enterica serovar Paratyphi A) from serovar Typhi (S. enterica serovar Typh...

The increasing prevalence of extended-spectrum β-lactamase (ESBL)-producing Entero-bacteriaceae has greatly affected the clinical efficacy of β-lactam antibiotics in the management of urinary tract infections (UTIs). The limited treatment options have resulted in the increased use of carbapenem. However, flomoxef could be a potential carbapenem-spa...

Burkholderia pseudomallei, a Gram‐negative bacterial pathogen that causes melioidosis, is of public health importance in endemic areas including Malaysia. An investigation of the molecular epidemiology links of B. pseudomallei would contribute to better understanding of the clonal relationships, transmission dynamics and evolutionary change. Multi‐...

Emerging evidence has shown a link between the perturbations and development of the gut microbiota in infants with their immediate and long-term health. To better understand the assembly of the gut microbiota in preterm infants, faecal samples were longitudinally collected from the preterm (n = 19) and term (n = 20) infants from birth until month 1...

Microbial dysbiosis has been implicated in the pathogenesis of oral cancer. We analyzed the compositional and metabolic profile of the bacteriome in three specific niches in oral cancer patients along with controls using 16SrRNA sequencing (Illumina Miseq) and DADA2 software. We found major differences between patients and control subjects. Bacteri...

Phytase enzyme is supplemented to poultry feed to improve phosphorus (P) availability. Mitsuokella jalaludinii, bacteria isolated from the rumen of cattle, has been reported as a cheaper alternative source of phytase. As much nutrients are trapped within the phytate complex, we hypothesized that the supplementation of M. jalaludinii phytase to poul...

Aims: The fluid of Nepenthes gracilis harbors diverse bacterial taxa that could serve as a gene pool for the discovery of the new genre of antimicrobial agents against multidrug-resistant Klebsiella pneumoniae. The aim of this study was to explore the presence of antibacterial genes in the fluids of N. gracilis growing in the wild. Methods: Using...

The gut-brain axis is a hot topic in Parkinson's disease (PD). It has been postulated that gut pathogens and dysbiosis can contribute to peripheral inflammatory states or trigger downstream metabolic effects that exacerbate the neurodegenerative process in PD. Several preclinical and clinical studies have demonstrated disrupted intestinal per-meabi...

Background: Gastrointestinal carriage of multidrug resistant (MDR) Gram-negative bacilli, especially Klebsiella pneumoniae and Escherichia coli, was highly associated with severe nosocomial infections. The main objectives of this study were to determine the clonal relatedness of intestinal carriage and transmission risk factors of MDR E. coli and...

Coffee is rich in antioxidant and has been shown to confer various health benefits. Here, we investigated the effect of single‐dose coffee consumption in healthy human subjects. About 30 healthy volunteers were recruited and given a serving of sugar free black coffee. Urine and fecal samples were collected and analyzed. Significant changes in urina...

Objective: To determine whether probiotics are effective for constipation, a common and often difficult-to-treat problem, in Parkinson's disease (PD). Methods: In this double-blind, randomized placebo-controlled single-centre trial, 280 PD patients were screened and 72 eligible patients were block-randomized (1:1) to receive either multi-strain...

Typhoid fever is a disease caused by Salmonella Typhi that was implicated in millions of illnesses worldwide annually. Individuals that do not recover fully from typhoid fever can become asymptomatic carriers of the disease. Host antibodies against the S. Typhi antigens, HlyE (for acute typhoid) and YncE (for carriers) were previously reported to b...

The gastrointestinal tract of humans and swine consist of a wide range of bacteria which interact with hosts metabolism. Due to the differences in co-evolution and co-adaptation, a large fraction of the gut microbiome is host-specific. In this study, we evaluated the effect of close human-animal interaction to the faecal metagenome and metabonome o...

The emergence of carbapenemase-producing Enterobacteriaceae has become a major global concern. OXA-48-like carbapenemase gene and its variants have been increasingly reported worldwide. This study reported the first OXA-181-producing Klebsiella quasipneumoniae isolate in Malaysia. This bacterium was isolated from blood specimen of a three-year-old...

Background Probiotics are the most recognised alternative to antibiotic growth promoters (AGPs) for poultry production. They adhere to the intestinal epithelial cells to exert their beneficial effects on the host. However, this is often restricted by indigenous gut microbes that compete for adhesion sites and nutrients. Therefore, phage application...

OXA-48-like carbapenemase gene remains a hidden threat, as different OXA-48 variants have varying presentations of susceptibility to antibiotics that might affect the treatment decisions. Rapid detection and differentiation of OXA-48-like carbapenemase genes are critical for targeted treatment and infection control. In this study, we aimed to devel...

Background Resistance to colistin, the last line therapy for infections caused by multidrug-resistant Gram-negative bacteria represents a major public health threat. Citrobacter freundii B9-C2 which was isolated from the stool of preterm neonate on the first week of life, displayed resistance to almost all major antibiotics, including colistin. Thr...

Background: The rise of nature-based ecotourism in the past decade has introduced unprecedented challenges in managing the increasing interaction between humans and animals. The potential transmission of antibiotic resistant microbes between humans and non-human primate populations is a concern due to their genetic similarity. Malaysia is well kno...

Introduction: Incidence of leptospirosis has increased within the past few years in many countries. Its clinical presentations were generally nonspecific, making it difficult to assist in the diagnosis. Besides the determination of the common clinical features, the sociodemographic background is essential to identify high-risk populations to assist...

Background: Emerging evidence has shown a link between the perturbations and development of the gut microbiota in infants to their immediate and long-term health. In comparison to the healthy full-term neonate, preterm neonates experience disparate gut bacterial establishment (e.g. duration in the womb), colonisation (e.g. mode of delivery), and de...

Mangosteen is one of the best tasting tropical fruit widely cultivated in Southeast Asia. This study aimed to quantify xanthone content in different parts of Garcinia mangostana by LC-QTOF-MS and determine its influence on their cholinesterase inhibitory activities. The total xanthone content in G. mangostana was in the following order: pericarp >...

Cholera is an acute diarrheal illness caused by the Gram-negative bacterium Vibrio cholerae. The pathogen is known for its ability to form biofilm that confers protection against harsh environmental condition and as part of the colonisation process during infection. Coaggregation is a process that facilitates the formation of biofilm. In a prelimin...

The cervical microbiota constitutes an important protective barrier against the invasion of pathogenic microorganisms. A disruption of microbiota within the cervical milieu has been suggested to be a driving factor of sexually transmitted infections. These include Chlamydia trachomatis which frequently causes serious reproductive sequelae such as i...

Background: Klebsiella pneumoniae is a major opportunistic pathogen frequently associated with nosocomial infections, and often poses a major threat to immunocompromised patients. In our previous study, two K. pneumoniae (K36 and B13), which displayed resistance to almost all major antibiotics, including colistin, were isolated. Both isolates were...

Inclusion of phytase in animal feedstuff is a common practice to enhance nutrients availability. However, little is known about the effects of phytase supplementation on the microbial ecology of the gastrointestinal tract. In this study, freeze‐dried Mitsuokella jalaludinii phytase (MJ) was evaluated in a feeding trial with broilers fed a low avail...

The evolution of antimicrobial resistance (AMR) in pathogens has prompted extensive research to find alternative therapeutics. Plants rich with natural secondary metabolites are one of the go-to reservoirs for discovery of potential resources to alleviate this problem. Terpenes and their derivatives comprising of hydrocarbons, are usually found in...

The increasing prevalence of antibiotic resistant pathogens poses a serious threat to global health. However, less emphasis has been placed to co-relate the gene expression and metabolism of antibiotic resistant pathogens. This study aims to elucidate gene expression and variations in metabolism of multidrug resistant Klebsiella pneumoniae after ex...