MINISTRY OF EDUCATION AND
TRAINING
VIETNAM ACADEMY
OF SCIENCE AND TECHNOLOGY
GRADUATE UNIVERSITY SCIENCE AND TECHNOLOGY
----------------------------
NGUYEN CAM HA
RESEARCH ON SQUALENE FROM HETEROTROPHIC MARINE MICROALGA
SCHIZOCHYTRIUM MANGROVEI PQ6 ORIENTED AS FEEDSTOCK FOR
HEALTH FOOD, COSMETIC AND PHARMACEUTICAL
Major: Biochemistry
Code: 9 42 01 16
SUMMARY OF BIOLOGY DOCTORAL THESIS
Ha Noi - 2020
The doctoral thesis was completed at: Institute of Biotechnology, Graduate University of
Science and Technology, Vietnam Academy of Science and Technology.
Scientific supervisor: Prof. Dr. Dang Diem Hong
Institute of Biotechnology
Reviewer 1: …
Reviewer 2: …
Reviewer 3: ….
The doctoral thesis will be defended at the graduate university committee of doctoral
thesis evaluation at Graduate University of Science and Technology, Vietnam Academy of
Science and Technology on…………, date…….....month…….year 2020
See the detailed thesis at:
- Library of Graduate University of Science and Technology
- Vietnam National Library
LIST OF PUBLISHED WORKS (09)
1. Nguyen Cam Ha, Hoang Thi Minh Hien, Nguyen Hoang Ngan, Dang Diem Hong, Safety
assessment and the effect of squalene isolated from Schizochytrium mangrovei PQ6 on
serum HDL - Cholesterol levels in animal models. Academia Journal of Biology, 2019,
41(2), 39-48 (in Vietnamese)
2. Hoang Thi Lan Anh, Nguyen Cam Ha, Le Thi Thom, Hoang Thi Huong Quynh Pham
Van Nhat, Hoang Thi Minh Hien, Ngo Thi Hoai Thu, Dang Diem Hong, Different
fermentation strategies by Schizochytrium mangrovei strain PQ6 to produce feedstock for
exploitation of squalene and omega-3 fatty acids. Journal of Phycology, 2018, 54 (4), 550-
556 (SCI, Q1; IF-3.0).
3. Nguyen Cam Ha, Hoang Thi Minh Hien, Dang Diem Hong, Hypocholesterolemic
mechanisms of squalene extracted from Schizochytrium mangrovei PQ6 in hepatocytes.
Proceeding of national Biotechnology conference 2018, Publishing house of natural
sciences and technology; 2018, 589-594 (in Vietnammese).
4. Nguyen Cam Ha, Hoang Thi Minh Hien, Le Thi Thom, Hoang Thi Huong Quynh, Dang
Diem Hong, Optimization of fermentation conditions for squalene production by
heterotrophic marine microalgae Schizochytrium mangrovei. Academia Journal of
Biology, 2017, 39(3), 449-458.
5. Hoang Thi Minh Hien, Nguyen Cam Ha, Le Thi Thom, Dang Diem Hong, Squalene
promotes cholesterol homeostasis in macrophage and hepatocyte cells via activation of
liver X receptor (LXR) α and β. Biotechnology Letters, 2017, 39 (8), 1101-1107 (SCI, Q2;
IF-1.7).
6. Dang Diem Hong, Nguyen Cam Ha, Le Thi Thom, Luu Thi Tam, Hoang Thi Lan Anh,
Ngo Thi Hoai Thu, Biofuel from Vietnam heterotrophic marine microalgae: Biodiesel and
salvaging co-products ((polyunsaturated fatty acids, glycerol and squalene) during
biodiesel producing process. Journal of Biology, 2017, 39 (1): 51-60. (in Vietnamese)
7. Nguyen Cam Ha, Le Thi Thom, Hoang Thi Huong Quynh, Pham Van Nhat, Hoang Thi
Lan Anh and Dang Diem Hong, Extraction of squalene from Vietnam heterotrophic
marine microalga. Proceeding of The 4 the Academic conference on natural Science for
Yong Scientists, Master & PhD. Student from Asian Countries. 15-18 December, 2015 -
Bangkok, Thailand, 2016, 46-56.
8. Hoang Thi Lan Anh, Nguyen Cam Ha, Le Thi Thom, Dang Diem Hong, Optimization of
culture conditions and squalene enrichment from heterotrophic marine microalga
Schizochytrium mangrovei PQ6 for squalene production. Research Journal of
Biotechnology, 2016, 14 (2), 337-346 (SCI-E).
9. Nguyen Cam Ha, Le Thi Thom, Đang Diem Hong, Hoang Minh Hien, Study on
Hypolipidic effect of squalene extracted from heterotrophic marine microalgal
Schizochytrium sp. on HepG2 cells. Journal of Pharmacutical, 2016, 21 (4), 270 -274.
1
INTRODUCTION
1. The urgency of the thesis
Viet Nam has over 3200 km of coastline with a diversity of tropical
marine organisms, rich in species composition and natural compounds that can
be used in the food industry, agriculture, medicine… Microalgae with the main
advantages of being rich in nutrients, small cells (<10 µm), easy to digest, non-
toxic, high growth rate and resistance to harsh environmental conditions are
considered is the first link, an important primary biomass source in the food
chain of aquatic ecosystems. In addition, microalgae biomass also contains
many important bioactive compounds for humans and animals such as
pigments, vitamins, minerals, proteins, polyunsaturated fatty acids - PUFAs) ...
especially squalene.
Squalene - a natural tripterpene synthesized in plants, animals as
a precursor of steroid commonly is used in nutritional products, health care,
cosmetics and medicine. Squalene is widely used in the cosmetic industry as
anti-dry and softening effects, protecting the skin against light and UV ray.
Recent epidemiological studies have indicated that squalene can effectively
inhibit chemically induced lung, colon and skin tumourigenesis on
experimental animals. Squalene is also natural antioxidant that protects cells
from free radicals and highly reactive oxygen species, capable of enhancing
the activity of the immune system. The daily supplement with a high squalene
content (about 500 mg/day) has been shown to be essential in promoting
human health and nutrition, significantly reducing cardiovascular disease and
cancer. Therefore, they are also commonly used in pharmaceuticals.
The current major commercial sources of squalene are deep-sea sharks
and plant seed oils. However, overexploitation affects the conservation of
marine fish resources in the wild, as well as the dependence on soil and season
of oil crops, leading to a decrease in squalene exploitation. Meanwhile,
the demand for squalene is now increasing in the food, cosmetic,
and pharmaceutical industries. Thus, finding alternative sources of commercial
squalene are being advanced for researchers.
Microorganisms in general and marine microalgae in particular are a
potential source for squalene production on a large scale. Recently, a number
2
of heterotrophic marine microalgae species such as thraustochytrids have been
regarded as a promising cell factory for the production of high value
substances including squalene. However, the study on squalene in Vietnam has
been just started in 2012, the research results just stopped at providing the
initial scientific basis of squalene content from some microalgal strains, that
have not yet been obtained: optimal methods for squalene extraction, squalene
enrichment and purification; optimal cultivation conditions for potential
microalgae capable of producing high squalene; technological process to
produce biologically active squalene for use as health food, cosmetics and
pharmaceutical in Vietnam. Therefore, with the great goal on providing
squalene-rich products for public health from natural resources available in the
country, including microalgae, we wish to be carried out the project "Research
on squalene from heterotrophic marine microalgae Schizochytrium mangrovei
PQ6 oriented as feedstock in health food, cosmetics and pharmaceuticals”.
2. Research objectives of the thesis
- Screening and determining suitable culture conditions for strain of
Schizochytirum mangrovei PQ6 of Vietnam potential for squalene production.
- Determining suitable conditions for squalene extraction and
purification from selectable S. mangrovei PQ6 strain; evaluating the safety and
pharmacological/biological effects of extracted squalene oriented as feed stock
for human health food, cosmetics and pharmaceuticals.
3. The main research contents of the thesis
- Screening potential marine microalgal species/strains for squalene
production from some marine microalgal strains of Vietnam
- Optimizing the culture conditions to obtain algae biomass with high
squalene content in selected potential strains at flask and bioreactor 30 Liter
scales.
- Optimizing the conditions for squalene extraction, enrichment and
purification from selected marine microalgal strains; establishing the squalene
extraction and purification process; determining the purification and structure
of the extracted squalene.
