1.Effects of carbon and nitrogen sources on bacteriocin-inhibitory activity of postbiotic metabolites produced by Lactobacillus plantarum I-UL4
May Foong Ooi ; Nurzafirah Mazlan ; Hooi Ling Foo ; Teck Chwen Loh ; Rosfarizan Mohamad ; Raha Abdul Rahim ; Arbakariya Ariff
Malaysian Journal of Microbiology 2015;11(2):176-184
Aims: Postbiotic metabolites are metabolic compounds produced by probiotic lactic acid bacteria. These compounds
produced by Lactobacillus sp. have been shown to be effective substitutes for in-feed antibiotic in livestock due to their
broad inhibitory activity. Therefore, the aim of this study was to determine the effects of various carbon and nitrogen
sources on the bacteriocin-inhibitory activity of postbiotic metabolites produced by Lactobacillus plantarum I-UL4.
Methodology and results: The effects of various combinations of carbon and nitrogen sources on the bacteriocininhibitory
activity (expressed as modified bacteriocin activity, MAU/mL) of postbiotic metabolites produced by L.
plantarum I-UL4 were determined in basal media without micronutrients. The combination of glucose (20 g/L) and yeast
extract (22 g/L) gave the best bacteriocin-inhibitory activity as compared to other combinations. Maximum bacteriocininhibitory
activity of 1440 MAU/mL was achieved when 36.20 g/L of yeast extract was added as the sole nitrogen source
in modified de Man, Rogosa and Sharpe (MRS) medium. The glucose concentration was further optimised to enhance
the bacteriocin-inhibitory activity of the postbiotic metabolites. Lower bacteriocin-inhibitory activity was observed at 5, 10,
15 and 40 g/L in comparison to 20 g/L of glucose.
Conclusion, significance and impact of study: Maximum bacteriocin-inhibitory activity of postbiotic metabolites was
achieved at 1440 MAU/mL when 20 g/L of glucose and 36.20 g/L of yeast extract were added as the sole carbon and
nitrogen sources respectively in the modified MRS medium. Optimisation of other micronutrients present in MRS media
is necessary to further enhance the bacteriocin-inhibitory activity of postbiotic metabolites produced by L. plantarum IUL4.
Lactobacillus
2.Bioaerosol Levels in Indoor Air of Animal House and Hospital Laboratories; A Comparison with Library and Administrative Offices
Siti Marwanis Anua ; Nur Fatin Haris ; Nurzafirah Mazlan
Malaysian Journal of Medicine and Health Sciences 2020;16(Supp 1,January):94-100
Introduction: This study reported the concentration of bacterial and fungal bioaerosol at an animal house and hospital laboratories with the aim to compare the concentration levels at library and administrative offices. The bioaerosol levels between mid-shift (afternoon) were also compared to the concentration measured during pre-shift (morning). Methods: The NIOSH 0800 method utilising microbiological air sampler collecting airborne bacterial and fungal samples via impaction technique on Nutrient agar (NA) and Sabouraud Dextrouse agar (SDA) as culture medium, respectively. Sampling was done twice daily; before (pre-shift) and during working (mid-shift) hour. Results: The highest bacteria and fungi concentration was recorded at the animal house with median concentration of 2477 CFU/ m3 (IQR=121-2477) and 791 CFU/m3 (IQR = 379-2081), respectively. Higher-risked workplaces such as animal house and hospital laboratories have significantly higher bioaerosol concentrations compared to control workplaces such as library and administrative offices (p<0.05). Interestingly, there were significantly higher fungi concentrations during the pre-shift compared to the mid-shift, for both high risk and control workplaces. Conclusion: Animal research room had exceeded the recommended bioaerosol level of 500 CFU/m3, but all the other sites had concentrations below the recommended level. Appropriate control measures should be adhered such as practicing hygiene practices and housekeeping to minimise the bioaerosol exposure among the workers and occupants.
3.Trametes elegans: Sources and Potential Medicinal and Food Applications
Arivananthan Kanakasundar ; Nurzafirah binti Mazlan ; Ruzaina binti Ishak
Malaysian Journal of Medicine and Health Sciences 2023;19(No.1):348-353
The emergence of microfungi medicinal applications represents a turnover in the drug discovery field. These microfungi species are found in rotten woods and leaf litters collected from forests and reserves in some tropical countries
during rainy seasons. Among these species is Trametes elegans, which shares a commensalism-based relationship
with the host (plants), offering protection against external invasions. Thus, Trametes elegans possesses unique compositional values and gained tremendous interest in the last decade for its promising applications, such as inhibiting
a wide range of bacteria and harmful fungi, reducing oxidative stresses caused by free-radicals, nitric oxide, and
hydrogen peroxide, as well as extending food shelf-life. This mini-review reports the available literature on Trametes
elegans sources, studied extracts applications, and urges the investigation of other Trametes elegans potential applications as antiviral and anticancer agents.
4.Screening of Pathogenic Bacteria From Sea Cucumber Acaudina molpadioides In Pulau Langkawi, Kedah
Abigail Li Yen Lew ; Nurzafirah Mazlan ; Siti Marwanis Anua ; Thung Tze Young
Malaysian Journal of Medicine and Health Sciences 2020;16(No.3, September):42-46
Introduction: The outbreaks of foodborne diseases have been linked to the consumption of contaminated seafood. This research aims to screen the bacteria from the sea cucumbers Acaudina molpadioides collected from Pulau Langkawi. Methods: A total of 22 sea cucumber samples were collected randomly from Pulau Langkawi, Kedah, Malaysia. The samples were isolated and identified for the presence of bacteria using the conventional culture-based method. Presumptive bacteria colonies were subjected to various biochemical and antimicrobial susceptibility tests. Results: There were no bacterial growth in Hektoen Enteric (HE) agar and Thiosulphate-Citrate-Bile Salt (TCBS) agar. Positive samples were isolated from MacConkey (MAC) agar with 6 samples were Staphylococcus spp. (27.27%), 14 samples were Proteus spp. (63.63%) and 2 samples were Bacillus spp. (9.01%). Among these isolates, highest resistance was found against Ampicillin (45%) followed by Tetracycline (40%). Conclusion: The results indicate that the sea cucumbers Acaudina molpadioides were contaminated with potential bacteria. There is a need for adequate consumer protection measures.
5.Bioburden, phenotypic and spectroscopic characterisation of toxigenic and atoxigenic Aspergillus section Flavi from poultry feeds in Kelantan, Malaysia and Katsina, Nigeria
Baha' ; uddeen Salisu ; Siti Marwanis Anua ; Wan Ishak Wan Rosli ; Nurzafirah Mazlan
Malaysian Journal of Microbiology 2024;20(no.2):120-131
Aims:
The natural coexistence of high humidity and warm temperatures in Malaysia and Nigeria and poor storage facilities used by most poultry feed vendors provide suitable conditions for the proliferation of aflatoxigenic fungi and aflatoxigenesis. This study aims to characterise and evaluate the toxigenicity of Aspergillus section Flavi (ASF) from Malaysian and Nigerian poultry feeds.
Methodology and results:
This study utilised standard mycological techniques to determine the bioburden and distribution of mycoflora in 132 and 144 Malaysian and Nigerian poultry feeds, respectively. The ASF isolated from the samples were tested for aflatoxigenicity by thin-layer chromatography (TLC) and then characterised by multivariate using attenuated total reflectance fourier transformed infrared spectroscopy (ATR-FTIR). A total of 128 and 75 mould fungal isolates belonging to 12 and 11 species were obtained from the Malaysian and Nigerian samples with a bioburden ranging from 2.0 to 6.97 log CFU/g and the highest overall mean count of 5.66 ± 4.51 log CFU/g and 5.6 ± 4.76 log CFU/g, respectively. Aspergillus fumigatus, Aspergillus felis, Aspergillus flavus/parasiticus and Fusarium
graminearum were predominant in poultry feeds from both countries. Overall, 16 ASF were isolated (Malaysia = 7, Nigeria = 9), of which only three produce aflatoxins. The multivariate cluster analysis of ATR-FTIR spectra showed 97.78% similarity between the toxigenic and atoxigenic ASF with primary differences at 600 to 800 cm-1 and 2927 to 4000 cm-1 only.
Conclusion, significance and impact of study
The bioburden of fungal flora in the samples was higher than the ICMSF's acceptable range of 2.0 to 5.0 log CFU/g, indicating that they could be hazardous to poultry and necessitate stricter control measures. Irrespective of the country/source of samples, the ATR-FTIR has discriminated the toxigenic from atoxigenic ASF, implying its promising prospects for rapid identification of toxigenic ASF.
6. Toxicity effects of water extracts of Holothuria atra Jaeger in mice
Bin Hashim RIDZWAN ; Nurul Alia AZIZAN ; Zaitunnatakin ZAMLI ; Farah Hanis ZULKIPLI ; Nurzafirah MAZLAN ; Osama Yousef ALTHUNIBAT
Asian Pacific Journal of Tropical Biomedicine 2014;4(8):614-617
Objective: To determine lethal median dose (LD
7.Isolation and characterization of Carnobacterium maltaromaticum from the intestine of sea cucumber Acaudina molpadioides
Fatmawati Lambuk ; Nurzafirah Mazlan ; Thung Tze Young ; Rosida Abdullah ; Siti Marwanis Anua
Malaysian Journal of Microbiology 2023;19(no.2):149-155
Aims:
Acaudina molpadioides is a highly valued sea cucumber that is distributed on the muddy shores on the west coast of Peninsular Malaysia and is considered a local delicacy. Carnobacterium maltaromaticum is a type of lactic acid bacteria commonly found in meat, fish and dairy products and is usually isolated from the intestine of aquatic animals. It is scarcely reported from the intestine of A. molpadioides. This species is known to be pathogenic in fish but unknown in humans. The aim of this study was to isolate and characterize C. maltaromaticum from the intestine of A. molpadioides.
Methodology and results:
Using standard methods, the strains were tested for their biochemical and carbohydrate properties, antibiotic sensitivity tests, temperature sensitivity tests and molecular identification. A total of 1642 isolates were obtained, out of which three strains were chosen as they were catalase-negative, Gram-positive bacilli, negative to IMViC tests, γ-hemolysis, and positive to lactose and glucose tests. Molecular identification was made to strain AM47e and 16S rRNA genes sequence showed 99.93% similar to C. maltaromaticum. The sequence was submitted to GenBank as Carnobacterium maltaromaticum (Accession No: MZ 934727). The optimum growth temperature for the strains was 37°C and the antibiotic susceptibility showed they were sensitive to tetracycline, ampicillin and meropenem.
Conclusion, significance and impact of study
In conclusion, C. maltaromaticum can be isolated from the intestine of A. molpadioides with the potential of the probiotic applications and less potential vulnerability for consumers.
8.Toxicity effects of water extracts of Holothuria atra Jaeger in mice.
Ridzwan Bin HASHIM ; Nurul Alia AZIZAN ; Zaitunnatakin ZAMLI ; Farah Hanis ZULKIPLI ; Nurzafirah MAZLAN ; Osama Yousef ALTHUNIBAT
Asian Pacific Journal of Tropical Biomedicine 2014;4(8):614-617
OBJECTIVETo determine lethal median dose (LD50) and histopathological toxicity of water extract of Holothuria atra (H. atra) in mice.
METHODSThe behavioral changes, mortality and histopathology examination on liver were assessed in mice 14 d after the administration (i.p.) of H. atra water extract. Seven doses (10, 20, 30, 50, 100, 150 and 200 mg/kg) of H. atra were used. The control group was treated with normal saline.
RESULTSIn the acute study in mice, the water extracts of H. atra caused dose-dependent general behavior adverse affects and mortality. The main behavioral sign of toxicity was hypoactivity, noticed immediately after administration of the extract which was more obvious at the higher doses and persisted until death. Mortality increased with increasing doses, the calculated LD50 was 41 mg/kg in mice. The liver toxicity was confirmed by histopathological examination, which indicated the presence of abnormal hepatocytes with a distorted shape and undefined cell lining as well as enlarged nuclei in low doses groups. High doses groups indicated a more prominent distortion of the polyhedral hepatocytes with undefined cell lining, massive cytoplasm, pyknotic, karyorhexis and karyolytic nuclei (necrosis of hepatocytes). Control group showed polyhedral hepatocytes with defined cell lining arranged in cords and normal round nuclei, with granular cytoplasm.
CONCLUSIONSBecause of the relatively low LD50 value in the acute study in mice, it may be concluded that the H. atra water extract is toxic.
9.Prevalence of coral diseases in the coastal waters of Kota Kinabalu: The potential of microbial and environmental agents
Aslam Nor' ; ashikin Zuhairi ; Fikri Akmal Khodzori ; Siti Nur Hazwani Oslan ; Nurzafirah Mazlan ; Hariz Khairul Hisham ; Kiu Yee Tong ; Abdul Muhaimin Zepri
Malaysian Journal of Microbiology 2023;19(no.6):735-751
Aims:
The Indo-Pacific coral populations are under increasing threats from bleaching events and coral disease
outbreaks. However, there is a significant gap in data and research on coral diseases in Malaysian waters. This study aimed to assess the prevalence of coral diseases and signs of compromised health at 27 reef sites in the coastal waters of Kota Kinabalu, Sabah.
Methodology and results:
We conducted coral surveys using the Coral Video Transect (CVT) method and measured
the prevalence using Coral Point Count with Excel Extension (CPCe) software. Our findings indicated that the majority of reefs appeared healthy (82.9% ± 1.8), while a smaller percentage displayed signs of disease (5.0% ± 0.6) or compromised health (12.1% ± 1.5). Reef sites exposed to higher levels of human activities exhibited a greater prevalence of coral diseases (e.g. yellow band disease, ulcerative white spots and skeletal eroding band) and signs of compromised health (e.g. sediment necrosis, skeletal damage and algal overgrowth). A total of 51 scleractinian hard coral genera were affected, with Porites and Acropora being the most predominantly affected by sediment necrosis and skeletal damage, respectively. A review of molecular approaches identified various coral pathogens, including Vibrio spp., which could potentially contribute to the occurrence of coral disease.
Conclusion, significance and impact of study
Unsustainable coastal development with unregulated human activities can exacerbate the severity of coral diseases and signs of compromised health. Therefor