- Selected microbial strains with cytotoxic activity of some cancer cell lines.
- Determine the structure of compounds with cytotoxic activity from selected strains.

About the science:
+ From 8 sediment samples collected in the waters of Vung Ang - Ha Tinh, 40 strains of microorganisms have been isolated, including 20 strains of actinomycetes, 09 strains of bacteria and 11 strains of fungi.
+ The cytotoxic and anti-inflammatory activities of 40 isolates have been evaluated. Two strains (HT03 and HT06) have been selected with the highest biological activity to inhibit all 5 cancer cell lines at both the test concentrations 30 µg/ml and 100 µg/ml; inhibited all 3 Gram-positive strains E. faecalis, S. aureus and B. cereus and 1 fungus C. albicans with MIC values respectively 32-64-16-16μg/ml and 16-32-16-8μg/ ml.
+ The species has been identified by molecular biology of two strains. Strain HT03 belongs to the species Streptomyces fradiae and HT06 belongs to the species Nocardiopsis synnemataformans.
+ From the culture fluid of Streptomyces fradiae strains HT03 and Nocardiopsis synnemataformans HT06, 16 compounds were isolated, including 1 new compound 4βC-Glucopyranosil-3,5-dihydroxy-2-metoxy-benzoic acid (9).
+ Three compounds (5), (7) and (13) have shown activity on studied cancer cell lines with IC50 values from 29.23-93.59 µg/mL.
+ Sixteen isolated compounds showed activity against 1 to 3 strains of bacteriophage. In which compounds 3, 7, 8, 13. 15 and 16 showed activity against 3-4 microorganisms with MIC values from 8 to 128 µg/mL; only compounds 2, 7 and 11 showed the ability to inhibit 1 strain of gram-negative bacteria E. coli ATCC25922. In addition, 6 out of 16 isolated compounds (substances 1, 3, 6, 8, 9 and 15) showed activity against the yeast C. albicans.
+ Especially, the new compound (9) showed good activity against 2 strains of S.aureus ATCC25923 and C.albicans ATCC10231 with MIC values of 32 and 16 µg/mL, respectively.
As can be seen, the results of isolation and screening for antibiotic and cytotoxic activity of secondary compounds from actinomycetes Streptomyces fradiae HT03 and Nocardiopsis synnemataformans HT06 have yielded some bioactive compounds. study quite well, enriching data sources of natural compounds from marine environment in Vietnam.

A new substance has been isolated: 4βC-Glucopyranosil-3,5-dihydroxy-2-metoxy-benzoic acid(9).

- Scientific papers in referred journals:
International articles:
1.    Vu thi Quyen, Vu Thi Thu Huyen, Nguyen Mai Anh, Nguyen Thi Hue, Phi Thi Dao¬, Nguyen Thuy Linh, Pham Van Cuong, and  Doan Thi Mai Huong, Le Thi Hong Minh (2021), antimicrobial secondary metabolites from the marine-deverd actinomycete Nocardiopsissynnemataformans HT06. Chemistry of Natural Compounds (chấp nhận đăng)
Scientific articles in the country:
2.    Vũ Thị Quyên,Nguyễn Mai Anh, Vũ Thị Thu Huyền, Nguyễn Thị Giang An, Phí Thị Đào, Nguyễn Thị Huệ, Đoàn Thị Mai Hương, Phạm Văn Cường, Lê Thị Hồng Minh (2021), Các chất thứ cấp có hoạt tính sinh học được phân lập từ chủng Streptomyces fradiae HT03 có nguồn gốc từ trầm tích thuộc vùng biển Vũng Áng, Hà Tĩnh. Hội thảo quốc gia: Ứng dụng công nghệ sinh học trong chế biến, bảo quản và phát triển thực phẩm bảo vệ sức khoẻ con người Hà nội 08 tháng 12 năm 2021.
3.    Vũ Thị Quyên, Vũ Thị Thu Huyền, Nguyễn Mai Anh, Nguyễn Hải Đăng, Đoàn Thị Mai Hương, Phạm Văn Cường, Lê Thị Hồng Minh (2021), Phân lập, sàng lọc và định danh một số chủng xạ khuẩn có khả năng kháng vi sinh vật kiểm định và gây độc tế bào từ các mẫu trầm tích vùng biển Vũng Áng tại Hà.Tạp chí Công nghệ Sinh học 19(3): 557-568.
- Technological products (describe in details: technical characteristics, place):
+ The collection of 40 microorganisms (including 20 actinomycetes, 09 bacteria and 11 fungal strains) is stored in a -80oC cabinet on the 2nd floor of building B1 of the Institute of Marine Biochemistry.
+ The collection of 16 clean substances is stored in a 4oC cabinet in the Biotechnology room.

It is necessary to continue to have more in-depth studies on other biological activities for some substances with good antimicrobial activity in order to aim for future applications.

It is necessary to continue to study isolated microbial strains in order to find new biologically active substances that have not been researched within the framework of this topic. At the same time, expanding the research direction in other marine areas of our country to detect strains of marine microorganisms capable of producing compounds with high biological activity.