Discovery of antibacterial compounds from marine microorganisms in central Vietnam
Antibiotic resistance is a major challenge today, as many types of bacteria causing infectious diseases have developed resistance to conventional treatments. Vietnam is no exception to this trend and is even among the countries with the highest rates of antibiotic resistance. This raises an urgent need to find new, more effective and safer antimicrobial compounds.
Recently, Associate Professor, Dr. Doan Thi Mai Huong and colleagues from the Institute of Marine Biochemistry have collaborated with the National Museum of Natural History of the French Republic to carry out a research project on: "Discovery of secondary compounds with antimicrobial activity from selected microbial strains in the central coastal region of Vietnam" (code: QTFR01.02/21-22). The research has achieved remarkable scientific results and opened up many opportunities for international cooperation in the future.
Searching for valuable compounds from the ocean
Within the framework of the mission, Associate Professor, Dr. Doan Thi Mai Huong and the research team successfully collected and isolated 7 strains of microorganisms in the central coastal region of Vietnam. Through the screening process, 2 strains of microorganisms with good antimicrobial activity were selected for identification and large-scale fermentation, namely Streptomyces sp. G222 and Aspergillus versicolor M852. From Aspergillus versicolor M852, 10 clean compounds were isolated and their chemical structures were determined. The compounds include alkaloids, cyclopeptides and phenolic compounds. Among the isolated compounds, 5 compounds denoted as M852-1, M852-2, M852-3, M852-6 and M852-9 showed antimicrobial activity on some tested microbial strains.
Colony morphology of strains M852 and G222
At the same time, in collaboration with French partners, the EtOAc extract of Streptomyces G222 strain was investigated based on LC-ESI-MS/MS spectral analysis and molecular networking, combined with the use of GNPS (Global Natural Product Social Molecular Networking) spectral libraries and Concise (Consensus Annotation Propagation of in silico Elucidation) bioinformatic tools to classify groups of substances and predict the structures of secondary compounds. From there, the presence of lipopeptide compounds, lichenysin and surfactin derivatives from Streptomyces G222 strain, was determined. The structures of the compounds were determined based on HR-ESI-MS spectral analysis, 1D and 2D nuclear magnetic resonance spectra. The absolute configuration of amino acids was determined based on the Marfey method. The combination of Vietnamese scientific knowledge and modern technology from France has helped improve the quality of research and expand international cooperation opportunities in the field of marine biochemistry.
Molecular network of lipopeptide compounds from EtOAc extract of Streptomyces sp. G222 strain
Assoc.Prof.Dr. Doan Thi Mai Huong shared: The research team not only discovered biologically active compounds but also built a sustainable cooperative relationship with French scientists. This is an important premise for continuing to research and exploit marine microbial resources for practical applications. In the future, the team and partners will continue to research and sequence microbial genomes, in order to catch up with global research trends and develop further in the search for secondary compounds from marine microorganisms.
The research results have provided an important database on marine microorganisms capable of synthesizing antimicrobial compounds, contributing to the development of potential compounds for the pharmaceutical industry. These findings mark a significant step forward in efforts to exploit Vietnam's marine resources, while opening up opportunities for international cooperation in research and application of marine microorganisms.
Translated by Quoc Khanh
Link to Vietnamese version
