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Noraziah Mohamad Zin,1 Mohd Shukri Baba,2 Abu Hassan Zainal-Abidin,3 Jalifah Latip,4 Noor Wini Mazlan,5 RuAngelie Edrada-Ebel6 1Programme of Biomedical Science, School of Diagnostic and Applied Health Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur, 2Department of Biomedical Sciences, Kulliyyah of Allied Health Sciences, International Islamic University Malaysia, Kuantan, 3Department of Parasitology, Faculty of Medicine, Universiti Teknologi MARA, Shah Alam, 4School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, 5Analytical and Environmental Chemistry, School of Marine and Environmental Sciences, Universiti Malaysia Terengganu, Kuala Terengganu, Malaysia; 6Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, UK Abstract: Endophytic Streptomyces strains are potential sources for novel bioactive molecules. In this study, the diketopiperazine gancidin W (GW) was isolated from the endophytic actinobacterial genus Streptomyces, SUK10, obtained from the bark of Shorea ovalis tree, and it was tested in vivo against Plasmodium berghei PZZ1/100. GW exhibited an inhibition rate of nearly 80% at 6.25 and 3.125 µg kg-1 body weight on day four using the 4-day suppression test method on male ICR strain mice. Comparing GW at both concentrations with quinine hydrochloride and normal saline as positive and negative controls, respectively, 50% of the mice treated with 3.125 µg kg-1 body weight managed to survive for more than 11 months after infection, which almost reached the life span of normal mice. Biochemical tests of selected enzymes and proteins in blood samples of mice treated with GW were also within normal levels; in addition, no abnormalities or injuries were found on internal vital organs. These findings indicated that this isolated bioactive compound from Streptomyces SUK10 exhibits very low toxicity and is a good candidate for potential use as an antimalarial agent in an animal model. Keywords: antimalarial, Shorea ovalis, in vivo, endophytic, Streptomyces, gancidin W

Muhanna M Alshaibani,1 Juriyati Jalil,2 Nik M Sidik,3 Ruangelie Edrada-Ebel,4 Noraziah M Zin1 1Programme of Biomedical Science, School of Diagnostic and Applied Health Sciences, Faculty of Health Sciences, 2Drug and Herbal Research Centre, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Kuala Lumpur, 3School of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi, Malaysia; 4Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland Background: Zingiber spectabile, commonly known as Beehive Ginger, is used as an ethnobotanical plant in many countries as an appetizer or to treat stomachache, toothache, muscle sprain, and as a cure for swelling, sores and cuts. This is the first report of isolation of Streptomyces strain from the root of this plant. Strain Universiti Kebangsaan 25 (SUK 25) has a very high activity to produce secondary metabolites against methicillin-resistant Staphylococcus aureus (MRSA), which is associated with high morbidity and mortality rates due to acquired multidrug resistance genes and causes medication failure in some clinical cases worldwide. Phylogenetic analysis based on the 16S ribosomal RNA gene sequence exhibited that the most closely related strain was Streptomyces omiyaensis NBRC 13449T (99.0% similarity). Aim: This study was conducted to carry out the extraction, identification, and biological evaluation of active metabolites isolated from SUK 25 against three MRSA strains, namely, MRSA ATCC 43300, MRSA ATCC 33591, and MRSA ATCC 49476. Materials and methods: The production of secondary metabolites by this strain was optimized through Thronton’s media. Isolation, purification, and identification of the bioactive compounds were carried out using reversed-phase high-performance liquid chromatography, high-resolution mass spectrometry, Fourier transform infrared, and one-dimensional and two-dimensional nuclear magnetic resonance. Results: During screening procedure, SUK 25 exhibited good antimicrobial potential against several strains of MRSA. The best biological activity was shown from fraction number VII and its subfractions F2 and F3 with minimum inhibitory concentration values at 16 µg/mL and 8 µg/mL, respectively. These two subfractions were identified as diketopiperazine cyclo-(tryptophanyl-prolyl) and chloramphenicol. Conclusion: On the basis of obtained results, SUK 25 isolated from Z. spectabile can be regarded as a new valuable source to produce secondary metabolites against bacteria, especially MRSA. Keywords: Zingiber spectabile, MRSA, SUK 25, cyclo-(tryptophanyl-prolyl), chloramphenicol, HR-MS, NMR

Background: The majority of persons with dementia (PWD) are mainly cared for by their family members in the home. Evidence is however scarce on family caregivers' psychosocial burden and quality of life in Asian countries including Malaysia. This study describes the baseline data of a telephone-delivered psychoeducational intervention study and examines the determinants of outcome measures (caregiver burden, depressive and anxiety symptoms, quality of life and caregiving self-efficacy) among Malaysian family caregivers to PWD., Methods: This was a cross-sectional study originated from the baseline survey of a randomized control trial of 121 family caregivers recruited from lists of PWD who were registered at memory and psychiatry clinics in three tertiary care hospitals in Malaysia. The participants were assessed for caregiver burden by the Zarit Burden Interview, depressive and anxiety symptoms by the Hospital Anxiety and Depression Scale, quality of life by the Control, Autonomy, Self-Realization, and Pleasure Scale, and caregiving self-efficacy by the Revised Scale for Caregiving Self-Efficacy., Results: Prevalence of caregiver burden was 69.4%, depressive symptoms 32.2% and anxiety symptoms 32.2%. Family caregivers to PWD having perceived peer support e.g., social/family/friend/significant other supports were less likely to report caregiver burden, depressive and anxiety symptoms, and more likely to report higher levels of quality of life and caregiving self-efficacy. Being married and PWD's ability to self-care were associated with lesser likelihood of experiencing caregiver burden, depressive and anxiety symptoms. The other determinants of greater probability of reporting better quality of life were caregivers' employment and having Islamic faith. Marital status (married), PWD's ability to self-care, spousal relationship with PWD and shared caregiving process were associated with higher likelihood of reporting caregiving self-efficacy., Conclusion: Caregiver burden, depressive and anxiety symptoms are prevalent in family caregivers to PWD in Malaysia. Social support and caregiving related factors influence family caregivers' quality of life and caregiving self-efficacy. Implementing psychoeducational intervention and support in the psychiatry and memory clinics may help improve the psychosocial burden, quality of life and caregiving self-efficacy in family caregivers of PWD., Trial Registration: ISRCTN14565552 (retrospectively registered)., (© 2024. The Author(s).)

Mycopharmaceuticals from basidiomycetes represent a promising source of new antimicrobials to overcome the challenges of multidrug-resistant bacteria. Here we report for the first time the in vitro activity of aurisin A, a dimeric sesquiterpenoid isolated from wild bioluminescent basidiomycetes Neonothopanus nambi DSM 24013, against methicillin-resistant Staphylococcus aureus (MRSA). Aurisin A revealed strong anti-MRSA activity with minimum inhibitory concentration 7.81 μg/mL against ATCC 33591 and ATCC 43300 reference strains, and BD 16876 and BD 15358 clinical strains. Activity against the clinical strains is 10- to 40-fold higher than that of the antibiotic fusidic acid. Furthermore, aurisin A proved to be more potent (MIC 3.91 μg/mL) in inhibiting growth of vancomycin-intermediate S. aureus (VISA) ATCC 700699 and displayed a rapid time-dependent bactericidal activity against MRSA (complete killing within 1 h). Additionally, aurisin A and oxacillin combination displayed synergy with notable decrease in the MICs of both compounds against MRSA. Notable synergism was also observed in combinations with linezolid and fusidic acid. Our findings indicate that aurisin A is a promising candidate for developing therapeutic agents against multidrug-resistant S. aureus and warrants further investigation., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)

The essential oil of Backhousia citriodora , commonly known as lemon myrtle oil, possesses various beneficial properties due to its richness in bioactive compounds. This study aimed to characterize the chemical profile of the essential oil isolated from leaves of Backhousia citriodora (BCEO) and its biological properties, including antioxidant, antibacterial, and antibiofilm activities. Using gas chromatography-mass spectrometry, 21 compounds were identified in BCEO, representing 98.50% of the total oil content. The isomers of citral, geranial (52.13%), and neral (37.65%) were detected as the main constituents. The evaluation of DPPH radical scavenging activity and ferric reducing antioxidant power showed that BCEO exhibited strong antioxidant activity at IC 50 of 42.57 μg/mL and EC 50 of 20.03 μg/mL, respectively. The antibacterial activity results showed that BCEO exhibited stronger antibacterial activity against Gram-positive bacteria ( Staphylococcus aureus and Staphylococcus epidermidis ) than against Gram-negative bacteria ( Escherichia coli and Klebsiella pneumoniae ). For the agar disk diffusion method, S. epidermidis was the most sensitive to BCEO with an inhibition zone diameter of 50.17 mm, followed by S. aureus (31.13 mm), E. coli (20.33 mm), and K. pneumoniae (12.67 mm). The results from the microdilution method showed that BCEO exhibited the highest activity against S. epidermidis and S. aureus , with the minimal inhibitory concentration (MIC) value of 6.25 μL/mL. BCEO acts as a potent antibiofilm agent with dual actions, inhibiting (85.10% to 96.44%) and eradicating (70.92% to 90.73%) of the biofilms formed by the four tested bacteria strains, compared with streptomycin (biofilm inhibition, 67.65% to 94.29% and biofilm eradication, 49.97% to 89.73%). This study highlights that BCEO can potentially be a natural antioxidant agent, antibacterial agent, and antibiofilm agent that could be applied in the pharmaceutical and food industries. To the best of the authors' knowledge, this is the first report, on the antibiofilm activity of BCEO against four common nosocomial pathogens.

Alternative solutions are eminently needed to combat the escalating number of infections caused by methicillin-resistant Staphylococcus aureus (MRSA). Bacteriocins produced by lactic acid bacteria are promising candidates for next-generation antibiotics. Studies have found that these stable and nontoxic ribosomally synthesized antimicrobial peptides exhibit significant potency against other bacteria, including antibiotic-resistant strains. Here the authors review previous studies on bacteriocins that have been effectively employed to manage MRSA infections. The authors' review focuses on the beneficial traits of bacteriocins for further application as templates for the design of novel drugs. Treatments that combine bacteriocins with other antimicrobials to combat pervasive MRSA infections are also highlighted. In short, future studies should focus on the pharmacodynamics and pharmacokinetics of bacteriocins-antimicrobials to understand their interactions, as this aspect would likely determine their efficacy in MRSA inhibition.

Endophytic actinobacteria offer great potential as a source of novel bioactive compounds. In order to investigate the potential for the production of secondary metabolites by endophytes, we recovered a filamentous microorgansism from the tree Antidesma neurocarpum Miq. After phenotypic analysis and whole genome sequencing we demonstrated that this organism, SUK42 was a member of the actinobacterial genus Kitasatospora . This strain has a small genome in comparison with other type strains of this genus and has lost metabolic pathways associated with Stress Response, Nitrogen Metabolism and Secondary Metabolism. Despite this SUK42 can grow well in a laboratory environment and encodes a core genome that is consistent with other members of the genus. Finally, in contrast to other members of Kitasatospora , SUK42 encodes saccharide secondary metabolite biosynthetic gene clusters, one of which with similarity to the acarviostatin cluster, the product of which displays α-amylase inhibitory activity. As extracts of the host plant demonstrate this inhibitory activity, it suggests that the potential medicinal properties of A. neurocarpum Miq might be provided by the endophytic partner and illustrate the potential for exploitation of endophytes for clinical or industrial uses., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zin, Ismail, Mark, Westrop, Schniete and Herron.)

The current review aims to summarise the biodiversity and biosynthesis of novel secondary metabolites compounds, of the phylum Actinobacteria and the diverse range of secondary metabolites produced that vary depending on its ecological environments they inhabit. Actinobacteria creates a wide range of bioactive substances that can be of great value to public health and the pharmaceutical industry. The literature analysis process for this review was conducted using the VOSviewer software tool to visualise the bibliometric networks of the most relevant databases from the Scopus database in the period between 2010 and 22 March 2021. Screening and exploring the available literature relating to the extreme environments and ecosystems that Actinobacteria inhabit aims to identify new strains of this major microorganism class, producing unique novel bioactive compounds. The knowledge gained from these studies is intended to encourage scientists in the natural product discovery field to identify and characterise novel strains containing various bioactive gene clusters with potential clinical applications. It is evident that Actinobacteria adapted to survive in extreme environments represent an important source of a wide range of bioactive compounds. Actinobacteria have a large number of secondary metabolite biosynthetic gene clusters. They can synthesise thousands of subordinate metabolites with different biological actions such as anti-bacterial, anti-parasitic, anti-fungal, anti-virus, anti-cancer and growth-promoting compounds. These are highly significant economically due to their potential applications in the food, nutrition and health industries and thus support our communities' well-being.

The race towards the development of user-friendly, portable, fast-detection, and low-cost devices for healthcare systems has become the focus of effective screening efforts since the pandemic attack in December 2019, which is known as the coronavirus disease 2019 (COVID-19) pandemic. Currently existing techniques such as RT-PCR, antigen-antibody-based detection, and CT scans are prompt solutions for diagnosing infected patients. However, the limitations of currently available indicators have enticed researchers to search for adjunct or additional solutions for COVID-19 diagnosis. Meanwhile, identifying biomarkers or indicators is necessary for understanding the severity of the disease and aids in developing efficient drugs and vaccines. Therefore, clinical studies on infected patients revealed that infection-mediated clinical biomarkers, especially pro-inflammatory cytokines and acute phase proteins, are highly associated with COVID-19. These biomarkers are undermined or overlooked in the context of diagnosis and prognosis evaluation of infected patients. Hence, this review discusses the potential implementation of these biomarkers for COVID-19 electrical biosensing platforms. The secretion range for each biomarker is reviewed based on clinical studies. Currently available electrical biosensors comprising electrochemical and electronic biosensors associated with these biomarkers are discussed, and insights into the use of infection-mediated clinical biomarkers as prognostic and adjunct diagnostic indicators in developing an electrical-based COVID-19 biosensor are provided.

The present research aimed to enhance the pharmaceutically active compounds' (PhACs') productivity from Streptomyces SUK 25 in submerged fermentation using response surface methodology (RSM) as a tool for optimization. Besides, the characteristics and mechanism of PhACs against methicillin-resistant Staphylococcus aureus were determined. Further, the techno-economic analysis of PhACs production was estimated. The independent factors include the following: incubation time, pH, temperature, shaker rotation speed, the concentration of glucose, mannitol, and asparagine, although the responses were the dry weight of crude extracts, minimum inhibitory concentration, and inhibition zone and were determined by RSM. The PhACs were characterized using GC-MS and FTIR, while the mechanism of action was determined using gene ontology extracted from DNA microarray data. The results revealed that the best operating parameters for the dry mass crude extracts production were 8.20 mg/L, the minimum inhibitory concentrations (MIC) value was 8.00 µg/mL, and an inhibition zone of 17.60 mm was determined after 12 days, pH 7, temperature 28 °C, shaker rotation speed 120 rpm, 1 g glucose /L, 3 g mannitol/L, and 0.5 g asparagine/L with R 2 coefficient value of 0.70. The GC-MS and FTIR spectra confirmed the presence of 21 PhACs, and several functional groups were detected. The gene ontology revealed that 485 genes were upregulated and nine genes were downregulated. The specific and annual operation cost of the production of PhACs was U.S. Dollar (U.S.D) 48.61 per 100 mg compared to U.S.D 164.3/100 mg of the market price, indicating that it is economically cheaper than that at the market price.

Naturally derived antimicrobial peptides (AMPs) are an attractive source of new antimicrobial agents. However, clinical application of AMPs is associated with poor bioavailability and toxicity. In this study, we address these limitations by designing a new series of chitosan derivatives to mimic the amphiphilic topology of AMPs. The synthesized chitosan derivatives were found to self-assemble into nanoparticles in the aqueous environment. Among the compounds, a chitosan derivative grafted with arginine and oleic acid (CH-Arg-OA) exhibited the most potent antimicrobial activity, especially against Gram-negative bacteria. It also caused minimal cell death when tested in HEK293 and HepG2 cell lines, thus confirming the role of cationicity and lipophilicity for selective bacteria targeting. CH-Arg-OA exhibited its antimicrobial activity by disrupting bacterial membranes and causing the leakage of cytoplasmic contents. Thus, amphiphilic chitosan nanoparticles offer a great promise as a new class of AMPs mimics that is effective against Gram-negative bacteria., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The data genome sequence of SUK 48 consists of 8,341,706 bp, comprising of one contig with a high G + C content of 72.33%. The genome sequence encodes for 67 tRNAs and 21 rRNAs in one contig. SUK48 was found to have low similarities with other Streptomyces sp. (81-93% ANI indices) indicating that the isolated strain has a unique genome property and is presumably a novel species. This genome includes 34 genetic clusters responsible for the synthesis of secondary metabolites, including two polyketide synthase (PKS) clusters; one PKS type II cluster gene, one PKS gene cluster type III, five NRPS genetic clusters, and five PKS/NRPS hybrid clusters., Competing Interests: The authors declare that they have no known competing financial interests or personal relation-ships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

Fungi are a rich source of secondary metabolites with several pharmacological activities such as antifungal, antioxidant, antibacterial and anticancer to name a few. Due to the large number of diverse structured chemical compounds they produce, fungi from the phyla Ascomycota, Basidiomycota and Muccoromycota have been intensively studied for isolation of bioactive compounds. Basidiomycetes-derived secondary metabolites are known as a promising source of antibacterial compounds with activity against Gram-positive bacteria. The continued emergence of antimicrobial resistance (AMR) poses a major challenge to patient health as it leads to higher morbidity and mortality, higher hospital-stay duration and substantial economic burden in global healthcare sector. One of the key culprits for AMR crisis is Staphylococcus aureus causing community-acquired infections as the pathogen develops resistance towards multiple antibiotics. The recent emergence of community strains of S. aureus harbouring methicillin-resistant (MRSA), vancomycin-intermediate (VISA) and vancomycin-resistant (VRSA) genes associated with increased virulence is challenging. Despite the few significant developments in antibiotic research, successful MRSA therapeutic options are still needed to reduce the use of scanty and expensive second-line treatments. This paper provides an overview of findings from various studies on antibacterial secondary metabolites from basidiomycetes, with a special focus on antistaphylococcal activity.

Background: Helicobacter pylori harbouring cag-pathogenicity island (cagPAI) which encodes type IV secretion system (T4SS) and cagA virulence gene are involved in inflammation of the gastric mucosa. We examined all the 27 cagPAI genes in 88 H. pylori isolates from patients of different ethnicities and examined the association of the intactness of cagPAI region with histopathological scores of the gastric mucosa., Results: 96.6% (n=85) of H. pylori isolates were cagPAI-positive with 22.4% (19/85) having an intact cagPAI, whereas 77.6% (66/85) had a partial/rearranged cagPAI. The frequency of cag2 and cag14 were found to be significantly higher in H. pylori isolated from Malays, whereas cag4 was predominantly found in Chinese isolates. The cag24 was significantly found in higher proportions in Malay and Indian isolates than in Chinese isolates. The intactness of cagPAI region showed an association with histopathological scores of the gastric mucosa. Significant association was observed between H. pylori harbouring partial cagPAI with higher density of bacteria and neutrophil activity, whereas strains lacking cagPAI were associated with higher inflammatory score., Conclusions: The genotypes of H. pylori strains with various cagPAI rearrangement associated with patients' ethnicities and histopathological scores might contribute to the pathogenesis of H. pylori infection in a multi-ethnic population., (Copyright © 2020 Sociedade Brasileira de Infectologia. Published by Elsevier España, S.L.U. All rights reserved.)

Chloramphenicol (CAP) and cyclo-(L-Val-L-Pro) were previously isolated from Streptomyces sp., SUK 25 which exhibited a high potency against methicillin-resistant Staphylococcus aureus (MRSA). This study aimed to profile gene expression of MRSA treated with CAP and cyclo-(L-Val-L-Pro) compounds using DNA microarray. Treatment of MRSA with CAP resulted in upregulation of genes involved in protein synthesis, suggesting the coping mechanism of MRSA due to the inhibition of protein synthesis effect from CAP. Most upregulated genes in cyclo-(L-Val-L-Pro) were putative genes with unknown functions. Interestingly, genes encoding ribosomal proteins, cell membrane synthesis, DNA metabolism, citric acid cycle and virulence were downregulated in MRSA treated with cyclo-(L-Val-L-Pro) compound, suggesting the efficacy of this compound in targeting multiple biological pathways. Contrary to CAP, with only a single target, cyclo-(L-Val-L-Pro) isolated from this study had multiple antimicrobial targets that can delay antibiotic resistance and hence is a potential antimicrobial agent of MRSA.

Leptospirosis is a worldwide zoonotic disease caused by spirochetes of the genus Leptospira. The clinical manifestation of leptospirosis is non-specific and frequently misdiagnosed as other illnesses. The aim of this study was to compare the diagnostic accuracies of two commercial tests for early diagnosis of Leptospira species: the IgM latex agglutination test (IgM LAT) and the IgM enzyme-linked immunosorbent assay (IgM ELISA). A total of 140 serum samples were obtained from patients suspected of leptospirosis at the Universiti Kebangsaan Malaysia Medical Centre (UKMMC). These serum samples were tested for the presence of Leptospira sp. using IgM LAT, IgM ELISA and MAT. From Table 1, IgM LAT showed 21% (n = 29) positive, 18% (n = 25) inconclusive and 61% (n = 86) negative, while IgM ELISA showed 6% (n = 8) positive, 6% (n = 8) inconclusive, 88% (n = 124) negative and MAT showed 11% (n = 16) positive, 47% (n = 65) inconclusive, 42% (n = 59) negative. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of IgM LAT were 68.8%, 57.6%, 30.6% and 87.2% respectively, while for IgM ELISA they were 37.5%, 89.8%, 50% and 84.1%, respectively as compared to MAT (Table 2). The results showed that IgM LAT had higher sensitivity but lower specificity compared to IgM ELISA. In conclusion, IgM LAT can be useful as an early screening test for early diagnosis of Leptospira sp., while IgM ELISA is a suitable method for reducing false negative detection of Leptospira sp. As both tests show moderate percentages (~65%) in accuracy, an additional test is required for better detection of Leptospira sp.

Introduction: BCR-ABL fusion gene, the oncogenic driver of CML, results from a translocation between short arms of chromosome 9 and 22. Monitoring of CML patients during treatment is essential, not only for tailoring the treatment but also to detect early relapse to enable timely intervention. Commonly used methods for detection of residual disease are conventional karyotyping, FISH and molecular methods. In this study, we compared FISH with QRT-PCR for detection of residual disease in CML., Materials and Methods: CML patients on tyrosine kinase inhibitor (TKI) therapy and on regular follow up at University Kebangsaan Malaysia Medical Center (UKMMC) were selected. A comparative study was conducted between FISH and QRT-PCR for BCR-ABL transcripts at diagnosis and during follow-up., Results: There was good correlation between FISH and QRT-PCR for BCR-ABL. At 6th month of follow-up post diagnosis, FISH had a sensitivity of 83.3% and specificity of 65.2% (k >0.339, p<0.033). At 12th month, the sensitivity of FISH was 83% and the specificity was 59.1% (k >0.286, p <0.065). Similarly, at the 24th month, FISH had a sensitivity of 100% and specificity of 68.8% (k >0.642, p<0.000)., Discussion: Early achievement of major molecular response (MMR) and complete cytogenetic remission (CCyR) were reliable predictors of long-term maintenance of molecular remission.

Background: Previous studies show that there is a changing trend of sexual and reproductive behaviour among youth and this requires more attention and awareness especially on sexually transmitted diseases (STD). This study was carried out to evaluate the knowledge, attitude and practice of sexually transmitted diseases among selected inmates of women shelter homes., Methods: A cross-sectional study was carried out by involving 60 participants whom aged in between 13 to 25 years old. The questionnaires were developed in 'Bahasa Melayu' and it has been anonymous guided questionnaires., Results: The result showed that the mean age of the participants was 17.9 years old and most of the participants have completed secondary school (91.7%). Overall, the level of knowledge of participants on STDs were classified into three groups; 'high knowledge' (33.3%), 'medium knowledge' (35.0%) and 'low knowledge' (31.7%). The majority have heard of HIV/AIDS (95%) but with respect to other STDs was less well known. Whereas, the mean score for attitude was 23.1 out total 25. Their knowledge level was not influenced by their age (p = 0.61) and socio-economic status (p = 0.85). However, their attitude was influenced by their age (p < 0.05)., Conclusion: Knowledge on non-HIV STDs is still lacking and risky behaviours have been practiced. Although there were high level of knowledge and attitude among them but their practice on sexuality contradicts it especially on contraceptive use and pre-marital sex.

The extent to which distinct bacterial endophyte communities occur between different plant organs and species is poorly known and has implications for bioprospecting efforts. Using the V3 region of the bacterial 16S ribosomal RNA (rRNA) gene, we investigated the diversity patterns of bacterial endophyte communities of three rainforest plant species, comparing leaf, stem, and root endophytes plus rhizosphere soil community. There was extensive overlap in bacterial communities between plant organs, between replicate plants of the same species, between plant species, and between plant organ and rhizosphere soil, with no consistent clustering by compartment or host plant species. The non-metric multidimensional scaling (NMDS) analysis highlighted an extensively overlapping bacterial community structure, and the β-nearest taxon index (βNTI) analysis revealed dominance of stochastic processes in community assembly, suggesting that bacterial endophyte operational taxonomic units (OTUs) were randomly distributed among plant species and organs and rhizosphere soil. Percentage turnover of OTUs within pairs of samples was similar both for plant individuals of the same species and of different species at around 80-90%. Our results suggest that sampling extra individuals, extra plant organs, extra species, or use of rhizosphere soil, might be about equally effective for obtaining new OTUs for culture. These observations suggest that the plant endophyte community may be much more diverse, but less predictable, than would be expected from culturing efforts alone.

Background: Streptomyces are well known for their capability to produce many bioactive secondary metabolites with medical and industrial importance. Here we report a novel bioactive phenazine compound, 6-((2-hydroxy-4-methoxyphenoxy) carbonyl) phenazine-1-carboxylic acid (HCPCA) extracted from Streptomyces kebangsaanensis , an endophyte isolated from the ethnomedicinal Portulaca oleracea., Methods: The HCPCA chemical structure was determined using nuclear magnetic resonance spectroscopy. We conducted whole genome sequencing for the identification of the gene cluster(s) believed to be responsible for phenazine biosynthesis in order to map its corresponding pathway, in addition to bioinformatics analysis to assess the potential of S. kebangsaanensis in producing other useful secondary metabolites., Results: The S. kebangsaanensis genome comprises an 8,328,719 bp linear chromosome with high GC content (71.35%) consisting of 12 rRNA operons, 81 tRNA, and 7,558 protein coding genes. We identified 24 gene clusters involved in polyketide, nonribosomal peptide, terpene, bacteriocin, and siderophore biosynthesis, as well as a gene cluster predicted to be responsible for phenazine biosynthesis., Discussion: The HCPCA phenazine structure was hypothesized to derive from the combination of two biosynthetic pathways, phenazine-1,6-dicarboxylic acid and 4-methoxybenzene-1,2-diol, originated from the shikimic acid pathway. The identification of a biosynthesis pathway gene cluster for phenazine antibiotics might facilitate future genetic engineering design of new synthetic phenazine antibiotics. Additionally, these findings confirm the potential of S. kebangsaanensis for producing various antibiotics and secondary metabolites., Competing Interests: The authors declare there are no competing interests.

Here we report the draft genome sequence of an endophytic Paenibacillus tyrfis strain isolated from the Universiti Kebangsaan Malaysia reserve forest, Malaysia. The genome size was approximately 8.04 Mb, and the assembly consisted of 107 scaffolds with 168 contigs, and had a G + C content of 53%. Phylogenetic analysis of strain SUK123 using the 16S rRNA gene revealed that it belonged to the family Paenibacillaceae with the highest similarity to Paenibacillus elgii SD T (99%). Whole genome comparison of SUK123 with related species using average nucleotide identity (ANI) analysis revealed a similarity of 98% to Paenibacillus tyrfis Mst1 T , 94% to Paenibacillus elgii B69 T , 91% to Paenibacillus ehimensis A2 T , 68% to Paenibacillus polymyxa SC2 T and 69% to Paenibacillus alvei DMS29 T . The draft genome was deposited at the European Nucleotide Archive (PRJEB21373).

In our search for new sources of bioactive secondary metabolites from Streptomyces sp., the ethyl acetate extracts from endophytic Streptomyces SUK 25 afforded five active diketopiperazine (DKP) compounds. The aim of this study was to characterize the bioactive compounds isolated from endophytic Streptomyces SUK 25 and evaluate their bioactivity against multiple drug resistance (MDR) bacteria such as Enterococcus raffinosus, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa, and Enterobacter spp., and their cytotoxic activities against the human hepatoma (HepaRG) cell line. The production of secondary metabolites by this strain was optimized through Thornton's medium. Isolation, purification, and identification of the bioactive compounds were carried out using high-performance liquid chromatography, high-resolution mass liquid chromatography-mass spectrometry, Fourier transform infrared spectroscopy, and nuclear magnetic resonance, and cryopreserved HepaRG cells were selected to test the cytotoxicity. The results showed that endophytic Streptomyces SUK 25 produces four active DKP compounds and an acetamide derivative, which were elucidated as cyclo -( L -Val- L -Pro), cyclo -( L -Leu- L -Pro), cyclo -( L -Phe- L -Pro), cyclo -( L -Val- L -Phe), and N -(7-hydroxy-6-methyl-octyl)-acetamide. These active compounds exhibited activity against methicillin-resistant S. aureus ATCC 43300 and Enterococcus raffinosus , with low toxicity against human hepatoma HepaRG cells. Endophytic Streptomyces SUK 25 has the ability to produce DKP derivatives biologically active against some MDR bacteria with relatively low toxicity against HepaRG cells line.

Streptomyces sp. produces bioactive compounds with a broad spectrum of activities. Streptomyces kebangsaanesis SUK12 has been identified as a novel endophytic bacteria isolated from ethnomedicinal plant Portulaca olerace , and was found to produce the phenazine class of biologically active antimicrobial metabolites. The potential use of the phenazines has led to our research interest in determining the genome sequence of Streptomyces kebangsaanensis SUK12. This Whole Genome Shotgun project has been deposited at DDBJ/ENA/GenBank under the accession number PRJNA269542. The raw sequence data are available [https://www.ncbi.nlm.nih.gov/Traces/study/?acc=SRP105770].

Natural products continue to play an important role as a source of biologically active substances for the development of new drug. Streptomyces , Gram-positive bacteria which are widely distributed in nature, are one of the most popular sources of natural antibiotics. Recently, by using a bioassay-guided fractionation, an antimalarial compound, Gancidin-W, has been discovered from these bacteria. However, this classical method in identifying potentially novel bioactive compounds from the natural products requires considerable effort and is a time-consuming process. Metabolomics is an emerging "omics" technology in systems biology study which integrated in process of discovering drug from natural products. Metabolomics approach in finding novel therapeutics agent for malaria offers dereplication step in screening phase to shorten the process. The highly sensitive instruments, such as Liquid Chromatography-Mass Spectrophotometry (LC-MS), Gas Chromatography-Mass Spectrophotometry (GC-MS), and Nuclear Magnetic Resonance ( 1 H-NMR) spectroscopy, provide a wide range of information in the identification of potentially bioactive compounds. The current paper reviews concepts of metabolomics and its application in drug discovery of malaria treatment as well as assessing the antimalarial activity from natural products. Metabolomics approach in malaria drug discovery is still new and needs to be initiated, especially for drug research in Malaysia.

The aim of this study is to analyze the differential proteins in MRSA ATCC 33591 treated with aqueous extract from Q. infectoria gall. Protein extracts were obtained from MRSA cells by sonication and were separated by 2D polyacrylamide gels. Protein spots of interest were extracted from the gels and identified using LC-ESI-QTOF MS. The concentration of Q. infectoria extract used for 2D-gel electrophoresis was subinhibitory concentration. Minimum inhibitory concentration (MIC) value of the extract against MRSA was 19.50 μg/mL with bacteriostatic action at 1x MIC from time-kill assay. However, the extract exhibited dose-dependent manner and was bactericidal at 4x MIC with more than 3 log10 CFU/mL reduction at 4 h. 2D-GE map showed that 18 protein spots were upregulated and another six were downregulated more than twofold (p < 0.05) after treatment with subinhibitory concentration. Out of six proteins being downregulated, four proteins were identified as ferritin and catalase, branched-chain alpha-keto acid dehydrogenase subunit E2, and succinyl-CoA ligase [ADP-forming] subunit beta. Seven upregulated proteins which have been successfully identified were 3-hydroxyacyl-CoA dehydrogenase, NAD binding domain protein, formate C-acetyltransferase, 3-hydroxyacyl-[acyl-carrier-protein] dehydratase FabZ, NAD dependent epimerase/dehydratase family protein, and phosphopantothenoyl cysteine decarboxylase. It is postulated that the main mechanism of aqueous extract from gall of Q. infectoria was most likely involved in energy metabolism and protein stress.

Endophytic bacteria, such as Streptomyces, have the potential to act as a source for novel bioactive molecules with medicinal properties. The present study was aimed at assessing the antimalarial activity of crude extract isolated from various strains of actinobacteria living endophytically in some Malaysian medicinal plants. Using the four day suppression test method on male ICR strain mice, compounds produced from three strains of Streptomyces (SUK8, SUK10, and SUK27) were tested in vivo against Plasmodium berghei PZZ1/100 in an antimalarial screen using crude extracts at four different concentrations. One of these extracts, isolated from Streptomyces SUK10 obtained from the bark of Shorea ovalis tree, showed inhibition of the test organism and was further tested against P. berghei-infected mice for antimalarial activity at different concentrations. There was a positive relationship between the survival of the infected mouse group treated with 50 µg/kg body weight (bw) of ethyl acetate-SUK10 crude extract and the ability to inhibit the parasites growth. The parasite inhibition percentage for this group showed that 50% of the mice survived for more than 90 days after infection with the parasite. The nucleotide sequence and phylogenetic tree suggested that Streptomyces SUK10 may constitute a new species within the Streptomyces genus. As part of the drug discovery process, these promising finding may contribute to the medicinal and pharmaceutical field for malarial treatment.

Background: The potential of secondary metabolites extracted from Streptomyces sp. to treat bacterial infections including infections with Staphylococcus aureus is previously documented. The current study showed significant antimicrobial activities associated with endophytic Streptomyces sp. isolated from medicinal plants in Peninsular Malaysia., Objectives: The current study aimed to determine anti-methicillin-resistant-Staphylococcus aureus (MRSA) activities of Streptomyces sp. isolates., Materials and Methods: Disc diffusion and Minimum Inhibitory Concentration (MIC) assay were used to determine the antibacterial activity of Streptomyces sp. isolates. Optimization of fermentation parameters for the most potent anti-MRSA extract in terms of medium type, pH, aeration rate, and culture period was also carried out. Lastly, toxicity of the extract against Chang liver cells was determined employing the MTT, 2- (3, 5- diphenyltetrazol-2-ium-2-yl) -4, 5-dimethyl -1, 3 - thiazole; bromide assay., Results: The results indicated Streptomyces sp. SUK 25 isolates showed the most potent anti-MRSA activity. Disc diffusion assay revealed that spread plate technique was more efficient in screening anti-MRSA activity compared to pour plate (P < 0.05). To determine anti-MRSA MIC of Streptomyces sp. SUK 25, Thronton media was used. Therefore, MIC was determined as 2.44 ± 0.01 µg/mL, and accordingly, the lowest MIC was 1.95 µg/mL based on a seven-day culture, pH7, and aeration rate of 140 rpm. The crude extract was not toxic against Chang liver cells (IC50 = 43.31 ± 1.24 µg/mL)., Conclusions: The Streptomyces sp. SUK 25 culturing was optimized using Thronton media, at pH 7 and aeration of 140 rpm. Further isolation and identification of bioactive compounds will develop anti-MRSA therapeutics.

Recently, the attention of researchers has been drawn toward the synthesis of chitosan derivatives and their nanoparticles with enhanced antimicrobial activities. In this study, chitosan derivatives with different azides and alkyne groups were synthesized using click chemistry, and these were further transformed into nanoparticles by using the ionotropic gelation method. A series of chitosan derivatives was successfully synthesized by regioselective modification of chitosan via an azide-alkyne click reaction. The amino moieties of chitosan were protected during derivatization by pthaloylation and subsequently unblocked at the end to restore their functionality. Nanoparticles of synthesized derivatives were fabricated by ionic gelation to form complexes of polyanionic penta-sodium tripolyphosphate (TPP) and cationic chitosan derivatives. Particle size analysis showed that nanoparticle size ranged from 181.03 ± 12.73 nm to 236.50 ± 14.32 nm and had narrow polydispersity index and positive surface charge. The derivatives and corresponding nanoparticles were evaluated in vitro for antibacterial and antifungal activities against three gram-positive and gram-negative bacteria and three fungal strains, respectively. The minimum inhibitory concentration (MIC) of all derivatives ranged from 31.3 to 250 µg/mL for bacteria and 188 to1500 µg/mL for fungi and was lower than that of native chitosan. The nanoparticles with MIC ranging from 1.56 to 25 µg/mLfor bacteria and 94 to 750 µg/mL for fungi exhibited higher activity than the chitosan derivatives. Chitosan O-(1-methylbenzene) triazolyl carbamate and chitosan O-(1-methyl phenyl sulfide) triazolyl carbamate were the most active against the tested bacterial and fungal strains. The hemolytic assay on erythrocytes and cell viability test on two different cell lines (Chinese hamster lung fibroblast cells V79 and Human hepatic cell line WRL68) demonstrated the safety; suggesting that these derivatives could be used in future medical applications. Chitosan derivatives with triazole functionality, synthesized by Huisgen 1,3-dipolar cycloaddition, and their nanoparticles showed significant enhancement in antibacterial and antifungal activities in comparison to those associated with native, non-altered chitosan.

The aim of this research was to identify the volatile metabolites produced in different organs (leaves, stem and roots) of Polygonum minus, an important essential oil producing crop in Malaysia. Two methods of extraction have been applied: Solid Phase Microextraction (SPME) and hydrodistillation coupled with Gas Chromatography-Mass Spectrometry (GC-MS). Approximately, 77 metabolites have been identified and aliphatic compounds contribute significantly towards the aroma and flavour of this plant. Two main aliphatic compounds: decanal and dodecanal were found to be the major contributor. Terpenoid metabolites were identified abundantly in leaves but not in the stem and root of this plant. Further studies on antioxidant, total phenolic content, anticholinesterase and antimicrobial activities were determined in the essential oil and five different extracts. The plant showed the highest DPPH radical scavenging activity in polar (ethanol) extract for all the tissues tested. For anti-acetylcholinesterase activity, leaf in aqueous extract and methanol extract showed the best acetylcholinesterase inhibitory activities. However, in microbial activity, the non-polar extracts (n-hexane) showed high antimicrobial activity against Methicillin-resistant Staphylococcus aureus (MRSA) compared to polar extracts. This study could provide the first step in the phytochemical profiles of volatile compounds and explore the additional value of pharmacology properties of this essential oil producing crop Polygonum minus.

The increment of rate in obesity, the phenomenon of fat phobia as well as the increased use of herbal medicine had lead to the emergence of herbal slimming products. However, numerous bacteria and heavy metal contaminations are often found in herbal products due to irregular handling practices. Ten different brands of products (labeled as A-J) were investigated. Seven heavy metals content such as As, Cd, Pb, Co, Cr, Cu and Zn were analyzed using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and bacterial presence was determined by counting the total aerobic count. The identification of isolates was carried out by macroscopic and microscopic observation, biochemical tests and confirmation using commercial kits of Microgen GN-ID A+B and API 20 E. The heavy metal contents in the samples were below the limit of the standard limitation by WHO and Health Canada. However, sample A contained the highest total daily intake of heavy metals. Total aerobic count was highest in sample H followed by G, A, B, C, F, D, E, I and J in which G and H exceeded the standard total aerobic count (10(5) CFU g(-1)) as given by WHO. A total of nine isolates of Bacillus spp. and ten gram-negative bacteria were isolated in which Bacillus cereus and Pseudomonas aeruginosa were found in samples C and F, respectively. Considering the fact that the herbal sliming products contained low concentration of heavy metals and bacteria count, it should be consumed with caution.

A spore-forming streptomycete designated strain SUK12(T) was isolated from a Malaysian ethnomedicinal plant. Its taxonomic position, established using a polyphasic approach, indicates that it is a novel species of the genus Streptomyces. Morphological and chemical characteristics of the strain were consistent with those of members of the genus Streptomyces. Analysis of the almost complete 16S rRNA gene sequence placed strain SUK12(T) in the genus Streptomyces where it formed a distinct phyletic line with recognized species of this genus. The strain exhibited highest sequence similarity to Streptomyces corchorusii DSM 40340(T) (98.2 %) followed by Streptomyces chrestomyceticus NRRL B-3310(T) (98.1 %). The G+C content of the genomic DNA was 74 mol%. Chemotaxonomic data [MK-9(H8) as the major menaquinone; LL-diaminopimelic acid as a component of cell-wall peptidoglycan; C12 : 0, C14 : 0, C15 : 0 and C17 : 1 as the major fatty acids; phospholipid type II] supported the affiliation of strain SUK12(T) to the genus Streptomyces. The results of the phylogenetic analysis and phenotypic data derived from this and previous studies allowed the genotypic and phenotypic differentiation of strain SUK12(T) from the related species of the genus Streptomyces. The DNA-DNA relatedness value between strain SUK12(T) and S. corchorusii DSM 40340(T) is 18.85±4.55 %. Strain SUK12(T) produces phenazine-1-carboxylic acid, known as tubermycin B, an antibacterial agent. It is proposed, therefore, that strain SUK12(T) ( = DSM 42048(T) = NRRL B-24860(T)) be classified in the genus Streptomyces as the type strain of Streptomyces kebangsaanensis sp. nov.

Objective: To genotypically characterize methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from medical and surgical wards in Universiti Kebangsaan Malaysia Medical Centre (UKMMC) in 2009., Methods: MRSA strains were collected and molecularly typed by pulsed-field gel electrophoresis (PFGE)., Results: PFGE typing on 180 MRSA isolated in UKMMC identified 5 pulsotypes (A-E) and 6 singletons, where pulsotypes B and C were suspected to be divergent clones originating from a single ancestor. This study also showed that most MRSA strains were isolated from swab (119 isolates), followed by blood (22 isolates), tracheal aspirate (11 isolates) and sputum (10 isolates). On the other hand, urine and bone isolates were less, which were 4 and 1 isolates, respectively. The distribution of different pulsotypes of MRSA among wards suggested that MRSA was communicated in surgical and medical wards in UKMMC, with pulsotype B MRSA as the dominant strain. Besides, it was found that most deceased patients were infected by pulsotype B MRSA, however, no particular pulsotype could be associated with patient age, underlying disease, or ward of admittance., Conclusions: Five pulsotypes of MRSA and 6 singletons were identified, with pulsotype B MRSA as the endemic strains circulating in these wards, which is useful in establishment of preventive measures against MRSA transmission.

Background: Predominantly cognitive tasks assigned to the shop floor can lead to decreased cognitive functions problems, thereby increasing occupational accident risks. A potential approach to prevent such circumstances is by improving operator's cognitive performance., Objective: This study aimed to examine whether heart rate variability (HRV) biofeedback training could improve cognitive performance among electronic manufacturing's operators., Participants: Subjects consisted of 36 female operators who were randomly assigned as the experimental (n=19), and control group (n=17)., Method: The experimental participants received five session of weekly HRV biofeedback training of 30-50 minutes each. Physiological stress profiles and cognitive performance were assessed at pre and post-intervention., Results: Significant group x time effects were observed for attention and memory (p< 0.01) but not present for cognitive flexibility. Significant higher total spectrum HRV and low frequency (LF) power also occurred during biofeedback sessions, in addition to slower respiration rate. Physiological stress profile showed that the biofeedback participants were able to increase their LF activity at baseline, stressor, and recovery periods from pre to post., Conclusion: This study demonstrates potential application of HRV biofeedback for operator's performance enhancement, associated with increases in HRV.

This study evaluated in vitro activity of 9 flavonoids in combination with vancomycin or oxacillin against vancomycin-intermediate Staphylococcus aureus (VISA) ATCC 700699 by employing the checkerboard method to obtain Minimal inhibitory concentration (MIC) and fractional inhibitory concentration (FIC) index. Six flavonoids namely hesperitin, rutin, naringenin, flavones, naringin and 3, 7-dihyroxyflavone which exhibited notable inhibitory activity (MIC values < 3200 μg/ml) were further evaluated for combination assay with antibiotics. The combinations of vancomycin+flavone and oxacillin+flavone were found synergistic with the FIC index value 0.094 and 0.126, respectively. Other combinations showed an additive interaction (FIC index = 1.063) but no antagonistic reaction (FIC index > 4) were observed. In time kill studies, oxacillin-flavone combination at synergistic concentration demonstrated bactericidal effect at 24 h period with concentration-dependent manner on the VISA strain. Following 1 h exposure, the combination also produced persistent effect on the bacteria growth for 2.9 hrs at 1x sub-MIC and more than 24 h at 5x of sub-MIC and there was a significant difference between both concentrations (p<0.05). Vancomycin-flavone combination, however, showed no concentration-dependent effect and lower PAE values (1.159 h and 2.322 h at 1x and 5x sub-MIC, respectively) on the VISA strain. In conclusion, flavone markedly intensifies the susceptibility of oxacillin against VISA and the combination can be implicated for further interaction studies at molecular level.

The need of natural antimicrobials is paramount to avoid harmful synthetic chemicals. The study aimed to determine the antifungal activity of natural compound chitosan and its nanoparticles forms against Candida albicans, Fusarium solani and Aspergillus niger. Chitosan nanoparticles were prepared from low (LMW), high molecular weight (HMW) chitosan and its derivative, trimethyl chitosan (TMC). Particle size was increased when chitosan/TMC concentration was increased from 1 to 3 mg/mL. Their zeta potential ranged from +22 to +55 mV. Chitosan nanoparticles prepared from different concentrations of LMW and HMW were also found to serve a better inhibitory activity against C. albicans (MIC(LMW) = 0.25-0.86 mg/mL and MIC(HMW) = 0.6-1.0 mg/mL) and F. solani (MIC(LMW) = 0.86-1.2 mg/mL and MIC(HMW) = 0.5-1.2 mg/mL) compared to the solution form (MIC = 3 mg/mL for both MWs and species). This inhibitory effect was also influenced by particle size and zeta potential of chitosan nanoparticles. Besides, Aspergillus niger was found to be resistant to chitosan nanoparticles except for nanoparticles prepared from higher concentrations of HMW. Antifungal activity of nanoparticles prepared from TMC was negligible. The parent compound therefore could be formulated and applied as a natural antifungal agent into nanoparticles form to enhance its antifungal activity.

The aim of this study was to examine the effect of resonant breathing biofeedback training for reducing stress among manufacturing operators. Resonant breathing biofeedback works by teaching people to recognize their involuntary heart rate variability and to control patterns of this physiological response. Thirty-six female operators from an electronic manufacturing factory were randomly assigned as the experimental group (n = 19) and the control group (n = 17). The participants of the intervention received 5 weekly sessions of biofeedback training. Physiological stress profiles and self-perceived depression, anxiety, and stress scale (DASS) were assessed at pre- and post-intervention. Results indicated that depression, anxiety, and stress significantly decreased after the training in the experimental group; they were supported by a significant increase in physiological measures. Overall, these results support the potential application of resonant biofeedback training to reduce negative emotional symptoms among industrial workers.

The galls of Quercus infectoria are commonly used in Malay traditional medicine to treat wound infections after childbirth. In India, they are employed traditionally as dental applications such as that in treatment of toothache and gingivitis. The aim of the present study was to evaluate the antibacterial activity of galls of Quercus infectoria Olivier against oral bacteria which are known to cause dental caries and periodontitis. Methanol and acetone extracts were screened against two Gram-positive bacteria (Streptococcus mutans ATCC 25175 and Streptococcus salivarius ATCC 13419) and two Gram-negative bacteria (Porphyromonas gingivalis ATCC 33277 and Fusobacterium nucleatum ATCC 25586). The screening test of antibacterial activity was performed using agar-well diffusion method. Subsequently, minimum inhibitory concentration (MIC) was determined by using twofold serial microdilution method at a concentration ranging between 0.01 mg/mL and 5 mg/mL. Minimum bactericidal concentration (MBC) was obtained by subculturing microtiter wells which showed no changes in colour of the indicator after incubation. Both extracts showed inhibition zones which did not differ significantly (P < 0.05) against each tested bacteria. Among all tested bacteria, S. salivarius was the most susceptible. The MIC ranges for methanol and acetone extracts were the same, between 0.16 and 0.63 mg/mL. The MBC value, for methanol and acetone extracts, was in the ranges 0.31-1.25 mg/mL and 0.31-2.50 mg/mL, respectively. Both extracts of Q. infectoria galls exhibited similar antibacterial activity against oral pathogens. Thus, the galls may be considered as effective phytotherapeutic agents for the prevention of oral pathogens.

From January 2008 to December 2009, 433 Streptococcus pneumoniae strains were examined to determine the serotype distribution and susceptibility to selected antibiotics. About 50% of them were invasive isolates. The strains were isolated from patients of all age groups and 33.55% were isolated from children below 5 years. The majority was isolated from blood (48.53%) and other sterile specimens (6.30%). Community acquired pneumonia (41.70%) is the most common diagnosis followed by sepsis (9.54%). Serotyping was done using Pneumotest Plus-Kit and antibiotic susceptibility pattern was determined by modified Kirby-Bauer disk diffusion method and measurement of minimum inhibitory concentration (MIC) using E-test strip. Ten most common serotypes were 19F (15.02%), 6B (10.62%), 19A (6.93%), 14 (6.70%), 1 (5.08%), 6A (5.08%), 23F (4.85%), 18C (3.93%), 3 (2.08%) and 5 (1.85%). Penicillin MIC ranged between ≤ 0.012-4 μg/ml with MIC₉₀ of 1 μg/ml. Penicillin resistant rate is 31.78%. The majority of penicillin less-susceptible strains belonged to serotype 19F followed by 19A and 6B. Based on the serotypes distribution 22 (44.00%), 28 (56.00%) and 39 (78.00%) of the invasive isolates from children ≤ 2 years were belonged to serotypes included in the PCV7, PCV10 and PCV13, respectively., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Aim of the Study: Many local plants are used in Malaysian traditional medicine to treat respiratory diseases including symptoms of tuberculosis. The aim of the study was to screen 78 plant extracts from 70 Malaysian plant species used in traditional medicine to treat respiratory diseases including symptoms of tuberculosis for activity against Mycobacterium tuberculosis H37Rv using a colorimetric microplate-based assay., Materials and Methods: Plant extracts were prepared by maceration in methanol (80%) and antituberculosis screening was carried out using Tetrazolium bromide microplate assay (TEMA) method to determine the minimum inhibitory concentration (MIC)., Results: Thirty-eight plant extracts from 36 plant species exhibited antituberculosis activity with MICs in the range of 1600-400 μg/ml. The leaf extract of Angiopteris evecta exhibited the highest activity with MIC of 400 μg/ml. Five other extracts, namely, Costus speciosus (stem and flower), Piper sarmentosum (whole plant), Pluchea indica (leaf), Pluchea indica (flower), and Tabernaemontana coronaria (leaf) exhibited antituberculosis activity, each with MIC of 800 μg/ml. To the best of our knowledge, this is the first report of in vitro high throughput screening of Malaysian medicinal plants for antituberculosis activity., Conclusions: Antituberculosis activity of extracts of some plants justifies, to a certain extent their ethnomedicinal uses as remedies for symptoms of tuberculosis. These results also support the general view that, selecting the plants based on ethnobotanical criteria would enhance the probability of finding species with antituberculosis activity., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Three novel endophytic streptomycetes have been isolated and characterized from plants with ethnobotanical uses on the Malay Peninsula including: Thottea grandiflora (family -Aristolochiaceae), Polyalthia spp. (family -Annonaceae), and Mapania sp. (family -Cyperaceae). Each isolate, as studied by scanning electron microscopy, has small hyphae, and produces typical barrel-shaped spores arising by hyphal fragmentation. Interestingly, although none has any detectable antibacterial killing properties, each has demonstrable killing activity against one or more pathogenic fungi including organisms such as Phytophthora erythroseptica, Pythium ultimum, Sclerotinia sclerotiorum, Mycosphaerella fijiensis and Rhizoctonia solani. Molecular biological studies on the rRNA gene sequence of each isolate revealed that it is distinct from all other genetic accessions of streptomyectes in GenBank, and each bears some genetic similarity to other streptomycetes. The bioactivity of each microbe was extractable in various organic solvents.

Hydroxyapatite (HA; Ca10(PO4)6(OH)2), is one of the significant implant materials used in Orthopaedics and Dental applications. However, synthetically produced HA may not be stable under ionic environment, which it will unavoidably encounter during its applications. In this paper, the in vitro effects of three HA materials derived from different resources, i.e. commercial HA (HAC), synthesised HA from pure chemicals (HAS) and synthesised HA from kapur sireh; derived traditionally from natural limestone (HAK), were studied. The HA disc samples were prepared and immersed in simulated body fluid (SBF) for 31-day period. The evaluation conducted focuses on the changes of the pH and the Calcium ion (Ca-ion) and Phosphate ion (P-ion) concentrations in the SBF solution, as well as the XRD and SEM data representing the reactions on the HA materials. From the XRD, it was found that HAK has the smallest crystallite sizes, which in turn affect the pH of the SBF during immersion. The Ca and P-ion concentrations generally decrease over time at different rates for different HA. Upon 1-day immersion in SBF, apatite growth was observed onto all three surfaces, which became more pronounced after 3-day immersion. However, the appetites formed were observed to be different in shapes and sizes. The reasons for the difference in the apatite-crystals and their subsequent effects on cells are still being investigated.