1.Traditional method of fish treatment, microbial count and palatability studies on spoiled fish
Ambiga Paneer Selvam ; Seri Intan Mokhtar ; Nur Ain Abd Aziz ; Seri Bunian Mokhtar
Malaysian Journal of Microbiology 2013;9(2):135-139
Aims: To evaluate the microbial count and palatability acceptance of spoiled fish after treatment with traditionally used natural solution.
Methodology and results: To compare microbial count of spoiled fish before and after treatment with natural solution practiced by local people in Malaysia, 10 g of spoiled fish was respectively rinsed with 100 mL of 0.1% of natural solution such as Averrhoa
bilimbi extract, rice rinsed water, rice vinegar, Citrus aurantifolia extract, salt, flour, and Tamarindus indica extract. Flesh of fish rinsed with rice vinegar was found to be able to reduce microbial count (CFU/mL = 0.37 X 107) more than 4.5 times when compared to spoiled fish (CFU/mL=1.67x 107). Spoiled fish that was treated with rice vinegar was prepared into a cutlet and fried.
The cutlet was subjected to palatability acceptance study by a group of residents in Palm Court Condominium, Brickfields, Kuala Lumpur. The palatability study from the Cronbach alpha shown that the taste have the reliability of 0.802, the aroma has the
reliability of 0.888, colour with the reliability of 0.772, texture or mouth feel have reliability of 0.840 and physical structure of the cutlet is 0.829.
Conclusion, significance and impact of study: Treatment of spoiled fish using rice vinegar as practice by local people
traditionally shown a significant reduction in microbial count and the vinegar-treated fish could be developed into a product that is safe and acceptable by the consumer.
2.Screening of lignocellulolytic fungi for hydrolyzation of lignocellulosic materials in paddy straw for bioethanol production
Mona Fatin Syazwanee Mohamed Ghazali ; Nur Ain Izzati Mohd Zainudin ; Nor Azwady Abd Aziz ; Muskhazli Mustafa
Malaysian Journal of Microbiology 2019;15(5):379-386
Aims:
Paddy straw is known to have lignocellulosic materials such as cellulose and hemicellulose which can be readily converted into fermentable sugar for production of bioethanol via simultaneous saccharification and fermentation (SSF). In order to produce ethanol competently, the degradation of biomass by cellulase and highly ethanol-producing microorganism in fermentation process are necessarily needed. However, there is lacking in cellulose degrading organism in producing adequate amount of lignocellulosic enzyme. Therefore, the screening and selection for the best fungi to hydrolyze the lignocellulosic materials as well as forming consortium between two species of fungi has become the main focus.
Methodology and results:
Thirteen strains of fast-growing fungi were tested qualitatively for cellulase (congo red staining) and polyphenol oxidase (Bavendamm test). All tested strains displayed lignocellulolytic fungi characteristics. The selection was narrowed down by quantitative assay on endoglucanase, exoglucanase, β-glucosidase and xylanase and the highest cellulases enzyme producer were Trichoderma asperellum B1581 (3.93 U/mL endoglucanase; 2.37 U/mL exoglucanase; 3.00 IU/mL β-glucosidase; 54.87 U/mL xylanase), followed by Aspergillus niger B2484 (5.60 U/mL endoglucanase; 1.08 U/mL exoglucanase; 1.57 IU/mL β-glucosidase; 56.85 U/mL xylanase). In compatibility test, both T. asperellum B1581 and A. niger B2484 were inoculated on the same Petri dish for 4 days and the interaction showed by the two species was mutual intermingling.
Conclusions, significance and impact of study
Both T. asperellum B1581 and A. niger B2484 produced the highest cellulase enzyme. Since both strains can co-exist and produce enzymes that complete each other, a fungal consortium was suggested to increase the yield of sugars in saccharification process.
3.Morphological and molecular characterization of Trichoderma species isolated from rhizosphere soils in Malaysia
Sharifah Siti Maryam Syd Abdul Rahman ; Nur Ain Izzati Mohd Zainudin ; Asma Aris ; Nor Azwady Abd Aziz
Malaysian Journal of Microbiology 2021;17(1):80-89
Aims:
Knowledge of the Trichoderma taxa is important for both control efficiency and environmental conservation.
Therefore, the objective of this study is to isolate and identify Trichoderma species from various rhizosphere soil
samples using phenotypic and molecular characterization.
Methodology and results:
Native Trichoderma spp. were isolated from agricultural fields in 17 sites from seven states
of Malaysia. These isolates were characterized via morphological observation and molecular phylogenetic analysis
based on the translation elongation factor-1α (tef1-α) gene. About 42 isolates were classified into eight Trichoderma
species, which are Trichoderma asperellum, T. hamatum, T. harzianum, T. koningiopsis, T. rodmanii, T. spirale, T. viride
and T. virens. Comparison of DNA sequences of tef1-α showed that the isolates were 98-100% similar to respective
Trichoderma species from GenBank, thus confirming the fungal identity. Phylogenetic trees of maximum likelihood (ML)
dataset of tef1-α inferred that the isolates were clustered according to species.
Conclusion, significance and impact of study
Findings in the present study will be beneficial for the purposes of
biodiversity conservation and plant disease management using biocontrol agents.
Trichoderma--isolation &
;
purification
;
Rhizosphere
4.A simple method for the determination of bioethanol from lignocellulosic materials using gas chromatography-flame ionisation detector (GC-FID)
Mona Fatin Syazwanee Mohamed Ghazali ; Muskhazli Mustafa ; Nur Ain Izzati Mohd Zainudin ; Nor Azwady Abd Aziz
Malaysian Journal of Microbiology 2022;18(1):123-127
Aims:
The utilisation of lignocellulosic biomass for bioethanol production reduces the dependency on fossil fuels as a source of energy and emission of greenhouse gas (GHG). However, studies in this emerging field are hampered by the cost of ethanol quantification methods. Due to the volatile nature of ethanol, the method for the quantification of bioethanol production should be reproducible and rapid to avoid any evaporation loss to the surroundings. Therefore, this study aimed to develop a simple, rapid and precise bioethanol quantification method using a gas chromatographyflame ionisation detector (GC-FID) without having to go through distillation process for ethanol purification.
Methodology and results:
The bioethanol was produced via consolidated bioprocessing (CBP) using Trichoderma asperellum B1581 and paddy straw. The peak corresponding to ethanol was obtained at 2.347 min with a peak area of 189.66, equating to 0.159% (v/v) or 1.25 g/L ethanol. A comparison between the quantity of ethanol detected by GC-FID and spectrophotometric analysis (340 nm) showed no significant difference (p>0.05) in the amount of ethanol detected by GC analysis, thus validating the accuracy of the GC method.
Conclusion, significance and impact of study
This work presents a simple, precise and reliable method to determine the amount of bioethanol in the sample using a GC-FID. Currently, there are many GC-FID methods available for the determination of ethanol/alcohol in a human blood samples or in beverages but not in bioethanol samples. Thus, this method was developed to facilitate the determination of bioethanol in the samples produced from lignocellulosic materials.
Chromatography, Gas
;
Flame Ionization
;
Ethanol