Day 1 :
- Soil Microbiology | Pharmaceutical Microbiology | Microbiology & Microbes World | Industrial Microbiology & Food Microbiology
University of Southern Mindanao, Philippines
Maria Elena M. Neyra-Tanabe has completed her doctoral degree in Microbiology from the University of the Philippines at Los Baños. Her research work includes food safety of aquaculture products, food fermentation, biocontrol and local effective microorganisms for agricultural crops and livestock. She has been a recipient of the 2014 IAFP Student Travel Grant and the 2016 STI Days Travel Grant. She won the 2016 SEA-EU STI Days Papers and Posters Competition Winner for Food Category. She has published several papers in reputed journals. Currently, she is working at the Uniservity of Southern Mindanao as an assistant professor.
Indigenous species of microalgae were isolated from Ligawasan Marsh in the Philippines to assess potential biotechnological applications. Thirteen species were identified namely: Anabaena sp., Chorella species A and B, Closterium sp., Navicula capitata, Navicula protractoides, Gomphonema sp., Oedigonium sp., Oscillatoria sp., Trachelomonas sp., Selenastrum sp., Chlamydomonas sp., and Spirogya sp. Chlorella, Chlamydomonas, Spirogya, and Navicula were the only species being identified to be considered potent for biomass production. Chlorella had the highest frquency occurence and relative abundance hence it was selected for further characterization. Based on morphological characterization, there were two distinct species of Chlorella. Chlorella A was round and has a cresent-shaped chloroplast while Chlorella B was elliptical and had visible pyrenoid inside. They were then subjected to proximate, phytochemical, and cytotoxicity analyses. Based on the results, Chlorella A had a crude fat of 0.55%, moisture of 11.64%, and crude protein of 12.50% while Chorella B had a crude fat of 0.95%, moisture of 12.64%, and crude protein of 25.81%. Phytochemical analyses indicated that both species contain alkaloids, tannins, and flavanoids. However, saponins were only detected in Chlorella B. Anthraquinone was absent from both species. Cytotoxicity analyses revealed that both species were non-toxic and safe for human and animal consumption. These results indicate that Chlorella A and B are potential as an alternative source of animal feed and/or natural products. Thus, it is recommended that further analyses of other bioactive components and optimization for mass cultivation be conducted .
University of KwaZulu-Natal, South Africa,
Stella has completed her MSc from University of KwaZulu-Natal, South Africa and currently a PhD candidate at University of KwaZulu-Natal, South Africa. She currently specializes in microbial biotechnology for bioremediation. Sumaiya is a microbiologist and academic at University of KwaZulu-Natal, South Africa. She specializes in environmental microbiology and microbial biotechnology.
Locally, the petroleum, aluminum and steel milling industries have expressed considerable interest in the utilization of bioremediation as a means for reducing their lubricant waste. The aim of this study was to determine the efficiency of microalgae Scenedesmus vacuolatus versus microalgal consortium (Chlamydomonas pitschmannii, Trebouxia australis and Pectinodesmus pectinatus) in the biodegradation of industrial coolant and spent lubricant waste products. To determine a biodegradation capability of the microalgae, dehydrogenase activity tests were carried out. Samples that indicated positive dehydrogenase activity where then analyzed weekly using gas chromatography-mass spectrometry, to track the biotransformation of hydrocarbons and confirm biodegradation of the total petroleum hydrocarbons. Statistical analysis with SPSS, p<0.05, indicated the microbial consortium to be better at degradation compared to Scenedesmus vacuolatus. Dehydrogenase activity for both the coolant rolling oil (0.058 ± 0.001 mg/mL), and the spent rolling emulsion (0.047 ± 0.002) was higher for the microbial consortium compared to S. vacuolatus, 0.046 ± 0.001 mg/mL (for both coolant and spent oil emulsions). Gas chromatographymass spectrometry confirmed 100% biodegradation by both Scenedesmus vacuolatus and microalgal consortium after five weeks. This data can now be used to upscale the experiments and develop a bioremediation strategy to be used by local industries.
University of KwaZulu-Natal, South Africa
Nyashadzashe completed her MSc from University of KwaZulu-Natal Pietermaritzburg, South Africa and is currently pursuing her PhD at the same institution. She specialises in biotechnology, focused on hydrocarbon bioremediation. Sumaiya is a Doctor of Microbiology and a Lecturer at University of KwaZulu-Natal Pietermaritzburg, South Africa. She specialises in Microbial biotechnology.
The aluminum and steel industry makes use of hydrocarbon rolling oils which are termed ‘spent oils’ after use. Hazardous waste management companies remove the spent oils, which eventually end up being dumped at local hazardous material dump sites. The lack of an environmentally friendly strategy to reduce hazardous waste from factories was the incentive for this research. The aim was to determine and monitor an indigenous Achromobacter aegrifaciens bacterial biotransformation/ biodegradation of Kerosene based rolling oils including the additives: methyl laurate, lauric acid, and Shellsol D100. This was done via dehydrogenase assays and Gas Chromatography-Mass Spectrometry. Achromobacter aegrifaciens bacterial biotransformation was also compared to that of an exogenous consortium of Lysinibacillus fusiformis and Pseudomonas synaxantha. Results were analyzed statistically, using SPSS version 24. The mean differences were significant at the 0.05 level for both the Dehydrogenase assay and Gas Chromatography-Mass Spectrometry. Further, subterminal oxidation was determined to be the main activation mechanism for the biotransformation. Methylation occurred during rolling oil biotransformation but was more prevalent in biotransformations of the additives, especially methyl laurate. Methylation resulted in less efficient biotransformations compared to subterminal oxidation. This bioremediation strategy can now be further established for larger volume bioreactors as we established that the toxic monoaromatic compounds were successfully degraded at the end of five weeks making this bioremediation strategy a viable alternative to the current dumping by waste companies.
University of Chittagong, Bangladesh
Dr Chowdhury Mohammad Monirul Hasan has completed his PhD from Kyushu Institute of Technology, Japan and postdoctoral studies from University of Kabangsaan Malaysia. He is the professor of Biochemistry and Molecular Biology, University of Chittagong, Bangladesh. He is interested in biofuel production from marine algae, metabolic engineering and microbiology. He has published more than 20 research papers in reputed journals
Escherichia coli, a facultative anaerobe shows a number of genetic responses to pH changes in their growth environment by regulating gene expression and protein profiles. Hence, E. coli have been widely used by applied microbiologists to try to steer the metabolism of this organism toward the production of molecules with biotechnological value. The effect of pH downshift on fermentation characteristics was investigated in a continuous culture of Escherichia coli at aerobic and micro-aerobic conditions. Regardless of oxygen availability, higher levels of acetate were associated with lower biomass yields and lower glucose consumption rates at pH 5.5 as compared to the observations made at pH 7.0. Observed gene expressions indicated that the down- regulation of the glucose uptake rate corresponded to the down-regulation of ptsG gene expression which in turn was caused by the up-regulation of mlc gene under the positive control of Crp. In accordance with up-regulation of arcA gene expression at acidic conditions, the expressions of TCA cycle-related genes such as icdA and gltA, and the respiratory chain gene cyoA were down-regulated, whereas cydB gene expression was up-regulated. Decreased activity of the TCA cycle caused more acetate formation at lower pH levels. Under micro-aerobic condition, higher levels of formate and lactate were produced at lower pH due to up-regulation of pflA, yfiD and ldhA genes. Meanwhile, lower levels of ethanol were produced due to the down-regulation of adhE gene at lower pH, as compared to the observation at neutral pH. The combined effect of pH and temperature on gene expression was also investigated and observed that decreases in the specific glucose consumption rate were associated with increases in the specific acetate production rate. This type of information is useful for the production of recombinant proteins, bio-molecules, simultaneous saccharification and fermentation (SSF) and strain improvement.
National Institute for Chemical-Pharmaceutical Research and Development, Romania
Microbial production of secondary metabolites and especially those with therapeutic importance, such as “antibiotics”, have been given significant attention worldwide regarding their role in the management of infectious disease. Nowadays, the antibiotic resistance is increasing dramatically and the discovery of new drugs from microbial sources represents a major challenge among the researches. Antibiotics are low molecular-weight molecules produced as secondary metabolites, mainly by microorganisms that live in the soil. Actinomycetes, mainly Streptomyces species, are well-known for bioactive compounds production.
The aim of our study was to investigate the ability of new microbial strains with potential of antibiotics production. The strains were preliminary isolate from soil samples and identified using MALDI-TOF mass-spectrometry as species which belong to the Streptomyces genus. Submerged fermentation was followed for the production of antibiotics and agar disc diffusion assay was done to determine the antimicrobial activity of the crude extract. The active metabolites were tested for antibiotic activity against two human pathogens, Escherichia coli ATCC 8739 and Staphylococcus aureus ATCC 6538 strains. The results showed a good antibacterial activity with the diameter of inhibition zones more than 25 mm in the case of S. aureus, and more than 15 mm in the case of E.coli. In conclusion, the isolated strains can represent an important source of antimicrobial bioactive substances, which need to be further explored.