In: Sydowia 77, (2024): 177-191; ISSN 0082-0598, DOI 10.12905/0380.sydowia76-2024-0177, Published online on December 12, 2024

Purification, characterization, and bioactivities of Physarum polycephalum microplasmodial intracellular polysaccharides.

Tuyen T.H. Do, Du H. Nguyen, Yen T.M. Nguyen, Steven L. Stephenson & Hanh T.M. Tran,*

1 School of Biotechnology, International University-VNU HCM, Ho Chi Minh City, Vietnam
2 Faculty of Biology and Environment, Ho Chi Minh City University of Industry and Trade, Ho Chi Minh City, Vietnam
3 Central Laboratory of Analysis, University of Science, Ho Chi Minh City, 700000, Vietnam; Vietnam National University,
Ho Chi Minh City, 700000, Vietnam
4 Faculty of Chemistry, University of Science, Ho Chi Minh City, 700000, Vietnam; Vietnam National University,
Ho Chi Minh City, 700000, Vietnam
5 Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, USA
* e-mail: ttmhanh@hcmiu.edu.vn

Do T.T.H., Nguyen D.H., Nguyen Y.T.M., Stephenson S.L. & Tran H.T.M. (2025) Purification, characterization, and bioactivities
of Physarum polycephalum microplasmodial intracellular polysaccharides. – Sydowia 77: 177–191.

Physarum polycephalum is a species of myxomycetes that can produce a significant amount of cell wall-less microplasmodia
in liquid media within a short period of time. Our previous study found that the deproteinated IPSs from P. polycephalum microplasmodia
significantly inhibited cancer cells. In this study, the deproteinated IPSs were further purified by ion exchange chromatography.
Based on carbohydrate and molecular weight analysis, three polysaccharide molecules (pp0, pp0.3, and pp0.4) with
the molecular weights of 305 kDa, 573 kDa and 1342 kDa, respectively, were obtained from the deproteinated sample. HPLC-UV
analysis showed that these polysaccharides had different monomers compositions. Pp0 and pp0.3 had glucose (99.49 % and
75.47 %, respectively) as the major monomer, whereas the main monomer of pp0.4 was galactose (93.09 %). Regarding biological
activity, pp0 had a significantly higher antioxidant activity. This polysaccharide also exhibited the highest antiproliferative activity
against the tested cancer cells among three fractions. At 1000 µg/mL, pp0 reduced the viability of HeLa and MCF-7 population
to 54.54 % and 63.81 %, respectively. Even though these activities were significantly lower than those of the positive control
(doxorubicin), pp0 was significantly safer for normal cells. Specifically, only 46.03 % of non-transformed BAE cell population
remained viable when treated with doxorubicin, whereas pp0 showed no inhibition toward them.

Keywords: anti-proliferative activity, DPPH scavenging activity, slime molds, DEAE cellulose-52 chromatography, ß-glucan.