Isolation and
Characterization of Microalgae with potential as human nutrition
Nguyen Phuong-Thao Pham, Minh-Thong Le, Bui Trung-Trinh Le, Thi Thanh-Nhan Luu and
Thien-Hoang Ho
Res. J. Biotech.; Vol. 20(5); 120-126;
doi: https://doi.org/10.25303/205rjbt1200126; (2025)
Abstract
Microalgae present significant potential as feedstock for biodiesel production,
industrial food applications and pharmacology, along with the production of various
high-value products such as pigments and polyunsaturated fatty acids. The selection
of strains is essential for maximizing economic feasibility. This study focused
on the characterization of two microalgal strains isolated from the Thi Nghe River
(Ho Chi Minh City, Vietnam). Phylogenetic analysis of the 18S rDNA-ITS region identified
the strains as Desmodesmus armatus and Monoraphidium subclavatum. The primary objectives
were to extract and to analyze chlorophyll a, chlorophyll b, carotenoids and phycocyanin
from these microalgae. Ultrasound-assisted extraction methods were employed to disrupt
the microalgal cells followed by pigment analysis.
The results revealed that Monoraphidium subclavatum contained significantly higher
levels of pigments compared to Desmodesmus armatus. Specifically, Monoraphidium
subclavatum exhibited a higher chlorophyll a content (632.817 ± 12.510 μg/g) than
Desmodesmus armatus (268.840 ± 16.024 μg/g). A similar trend was observed for chlorophyll
b (364.933 ± 11.801 μg/g in M. subclavatum vs. 162.147 ± 17.562 μg/g in D. armatus)
and carotenoids (1899.333 ± 24.007 μg/g in M. subclavatum vs. 180.0 ± 34.044 μg/g
in D. armatus). Interestingly, phycocyanin levels were higher in Desmodesmus armatus
(0.360 ± 0.010 μg/g) than in Monoraphidium subclavatum (0.247 ± 0.015 μg/g). These
findings underscore the potential of these strains for pigment production and biodiesel
applications, with M. subclavatum showing particularly promising results in food
industry.
