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https://ptsldigital.ukm.my/jspui/handle/123456789/499616Full metadata record
| DC Field | Value | Language |
|---|---|---|
| dc.contributor.advisor | Asmat Ahmad, Ass Prof (Dr) | - |
| dc.contributor.author | Dada Ayokunle Christopher (P57028) | - |
| dc.date.accessioned | 2023-10-13T09:33:11Z | - |
| dc.date.available | 2023-10-13T09:33:11Z | - |
| dc.date.issued | 2014-01-07 | - |
| dc.identifier.other | ukmvital:80352 | - |
| dc.identifier.uri | https://ptsldigital.ukm.my/jspui/handle/123456789/499616 | - |
| dc.description | Ketiadaan program pemantauan kualiti air pesisiran pantai dan kemungkinan kemasukan secara terns air sisa najis ke perairan riadah menyebabkan perairan pantai di Malaysia berpotensi menjadi sumber penyebaran bakteria yang rintang antibiotik atau virulen. Dalam kajian ini penyelidikan telah dijalankan untuk pengesahan kesesuaian enterococci sebagai penunjuk kualiti air pantai di Malaysia. Pendekatan multivariat sebanyak 20 parameter yang merangkumi anilisis kluster analisis komponen utama dan analisis faktorial telah digunakan. Gabungan kaedah kultur lazim dan kaedah molekul telah diguna untuk mengesan sifat virulen dan kerintangan antibiotic bagi pencilan enterococci (n = 264) yang dipencilkan dari perairan pantai Teluk Kemang, Bagan Lalang dan Teluk Cempedak. Pengiraan kepadatan enterococci dari pantai-pantai tersebut selama dua tahun menunjukkan kepadatan di atas arah ambang, terutamanya pacta musim hujan apabila kepadatan setinggi 1042 CFU/100 mL diperoleh. Di pantai Teluk Chempedak yang menerima masuk aliran sungai dan kumbahan bernajis di muara, kepadatan enterococci dalam sampel air pantai meningkat secara signifikan (x2: 26.53, df= 4; p < 0.0001) semakin dekat dengan muara. Analisis regresi linear berganda menghasilkan satu model padanan terbaik yang dapat meramal kepadatan enterococci dengan darjah keyakinan maksimum 69.64%. Analisis komponen utama dan analisis faktorial jelas menunjukkan enterococci dan kolifom najis sebagai parameter penting untuk pemonitoran kualiti air pantai. Kepadatan enterococci mempunyai korelasi dengan lebih banyak parameter berbanding dengan kolifom najis dan ini mencadangkan bahawa enterococci adalah mikrob penunjuk yang lebih baik. Kerintangan terhadap antibiotik adalah paling kerap terhadap asid nalidiksik (98.84%) dan paling jarang terhadap kloramfenikol (8.38%). Analisis Turkey-Kramer menunjukkan kekerapan kerintangan terhadap antibiotik pelbagai adalah tertinggi bagi pencilan dari Teluk Kemang (64.29%) berbanding dengan 13.51% untuk pencilan dari Bagan Lalang. Gen virulen cyl, esp, gelE dan asa masing-masing telah dikesan pada kekerapan 7.32%, 21.95%, 100% dan 63.41% bagi pencilan daripada kumbahan najis dan 0%, 20%, 67.27% dan 41.82% bagi pencilan dari perairan pantai Teluk Chempedak. Ujian Chi-square menunjukkan perbezaan signifikan (X 2 = 82.630, df= 20, p < 0.001) dalam kekerapan kewujudan enterococci (n=165) dalam sampel air dari Teluk Kemang dan Bagan Lalang. Terdapat persetujuan dalam identiti spesies melalui analisis jujukan lokus pelbagai tetapi gen pheS adalah lebih diskriminatori berbanding dengan gen rpoA, terutamanya untuk perbandingan antara spesies. Analisis RAPD-PCR menunjukkan variabiliti yang tinggi dalam kepelbagaian enterococci dan kumbahan najis sebagai sumber paling mungkin untuk kemasukan najis ke perairan pantai Teluk Chempedak. Analisis tip jujukan multi lokus bagi Enterococcus faecalis menghasilkan empat jenis jujukan (ST59, ST117, ST181 dan ST474). ST181 mempunyai kesamaan dalam enam daripada tujuh lokus yang diuji dengan E. faecalis ST6, salah satu ahli dalam kompleks klon strain yang rintang terhadap berbagai antibiotik yang berkait dengan kejadian endokarditis berjangkit di hospital. Kajian ini menunjukkan bahawa enterococci adalah penunjuk mikrob yang lebih baik untuk pemantauan kualiti air pesisir pantai di Malaysia. Kewujudan enterococci yang rintang terhadap pelbagai antibiotik dan bersifat virulen menunjukkan bahawa perairan pantai berupaya menjadi penyebar untuk kumpulan bakteria ini.,The lack of beach water quality monitoring programs and the possibility of direct wastewater discharges into seawater available for recreational purposes may present beaches in Malaysia as potential dissemination routes for antibiotic resistant or virulent bacteria. In this study, investigations were conducted to validate the suitability of enterococci as beach water quality indicator in Malaysia. A twenty parameter and multivariate approach incorporating cluster analysis, principal component analysis and factorial analysis was used. A combination of standard culture methods and molecular approaches were also used to investigate the occurrence of virulence characteristics and antibiotic resistance among enterococci isolates (n=264) recovered from Teluk Kemang, Bagan Lalang and Teluk Chempedak public recreational beaches. Enumeration of enterococci densities in these public recreational beaches over a two year period indicated above-threshold levels of enterococci, particularly during rainy seasons when levels up to 1042 CFU/100 mL were recorded. In Teluk Chempedak beach which receives both river and sewage discharge at a major outlet, median enterococci counts of beach water samples gradually increased at statistically significant levels (x2: 26.53, df= 4; p < 0.0001) with increasing proximity to river and sewage influx. Multiple linear regression analysis produced a best-fit model that could predict enterococci densities with 69.64% maximum confidence. Principal component analysis and factorial analysis clearly delineated enterococci and faecal coliforms as parameters that weighed strongly for beach water bacteriological quality monitoring. Enterococci densities correlated with more parameters than faecal coliforms, suggesting enterococci as better indicator for beach water monitoring. Levels of antibiotic resistance were highest to nalidixic acid (94.84%) and least to chloramphenicol (8.38 %). Turkey– Kramer analysis showed that the frequency of occurrence of multiple antibiotic resistance (MAR) isolates was higher in Teluk Kemang beach water (64.29 %) as compared to Bagan Lalang beach water (13.51 %). Virulence genes cyl, esp, gelE and asa were detected respectively in 7.32%, 21.95%, 100% and 63.41% of sewage influx isolates but at lower proportions of 0%, 20%, 67.27% and 41.82% respectively among Teluk Chempedak beach isolates. Chi-square test revealed significant differences (X 2 = 82.630, df = 20, p < 0.001) in the frequency of occurrence of enterococci isolates (n=165) recovered from Teluk Kemang and Bagan Lalang beaches. There was agreement in species identity in the multi locus sequence analysis but pheS gene was more discriminatory than rpoA gene, particularly for interspecies comparison. RAPD– PCR analysis revealed a high variability of enterococci diversity and indicated sewage discharge as a likely source of faecal enterococci loadings into Teluk Chempedak beach. Multi locus sequence typing analysis of Enterococcus faecalis produced four sequence types (ST59, ST117, ST181 and ST474). One of these (ST181) shared six out of seven tested loci with E. faecalis ST6, a member of the clonal complex of multi-drug resistant strains associated with hospital outbreaks of infective endocarditis. The findings of the study generally reveal enterococci as better indicator for beach water quality monitoring in Malaysia. Furthermore, MAR enterococci with virulence characteristics are recoverable from beach water suggesting the potential for the dissemination of antimicrobial resistant pathogens of same or other lineage in recreational beaches.,PhD | - |
| dc.language.iso | eng | - |
| dc.publisher | UKM, Bangi | - |
| dc.relation | Faculty of Science and Technology / Fakulti Sains dan Teknologi | - |
| dc.rights | UKM | - |
| dc.subject | Enterococci | - |
| dc.subject | Recreational beaches in Malaysia | - |
| dc.subject | Water quality - Measurement | - |
| dc.title | Enterococci in selected recreational beaches in Malaysia : quality aspects, antibiotic resistance, virulence traits and molecular identification | - |
| dc.type | Theses | - |
| dc.format.pages | 312 | - |
| dc.identifier.callno | TD367.C497 2014 tesis | - |
| dc.identifier.barcode | 001162 | - |
| Appears in Collections: | Faculty of Science and Technology / Fakulti Sains dan Teknologi | |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| ukmvital_80352+SOURCE1+SOURCE1.0.PDF Restricted Access | 9.3 MB | Adobe PDF |  View/Open |
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