In vitro Properties of Methanol Extract and Sodium Alginate of Sargassum polycystum C. Agardh Brown Seaweed Collected from Malaysia

Main Article Content

Jamie Mei-Lin Kok
Ching-Lee Wong


The edible brown seaweed, Sargassum polycystum C. Agardh was harvested from the coastal region of Malaysia. In this study, analysis of the nutrition and metal content in the methanol extract showed positive for sodium, potassium, magnesium, vitamins A and E and arsenic contamination. The brine shrimp lethality assay (BSLA) revealed the extract to be non-toxic with LC50 value of 15.60 mg mL?1 (LC50 > 1). The antioxidant and antibacterial activities of the methanol extract were measured through various bioassays. The structural and physicochemical characterisation of the NaAlg, analysed through the 1H-NMR analysis revealed the M:G ratio of NaAlg at 0.733 with mannuronic (M) and guluronic (G) fractions at FM = 0.423 and FG = 0.577, respectively. The degraded NaAlg through methods of ultraviolet irradiation and sonication showed an increment in the in vivo antioxidant activities at intervals of 15 min, 30 min, 60 min, 90 min and 120 min. The Fourier transform infrared spectroscopy (FTIR) spectra of polysaccharides taken before and after UV irradiation showed breakage of covalent bonds and thus, increase in the intensity of both O?H and C?O stretching vibrations. Therefore, the increment in antioxidant activities observed in the treated samples were related to changes seen in their molecular structures.


Rumpai laut coklat yang boleh dimakan, Sargassum polycystum C. Agardh dituai dari kawasan pantai Malaysia. Dalam kajian ini, analisis kandungan nutrisi dan logam dalam ekstrak metanol menunjukkan ia positif untuk natrium, kalium, magnesium, vitamin A dan E dan pencemaran arsenik. Brine shrimp lethality assay (BSLA) mendedahkan ekstrak tersebut tidak bertoksik dengan nilai LC50 15.60 mg mL?1 (LC50 > 1). Aktiviti antioksidan dan antibakteria ekstrak metanol diukur melalui pelbagai bioassai. Pencirian struktur dan fizik NaAlg yang dianalisis melalui analisis 1H-NMR, mendedahkan nisbah M:G NaAlg pada 0.733 dengan pecahan manuronik (M) dan guluronik (G) masing-masing pada FM = 0.423 dan FG = 0.577. NaAlg yang dinyahgred melalui kaedah sinaran ultraviolet (UV) dan sonikasi menunjukkan peningkatan dalam aktiviti antioksidan in vivo pada selang masa 15 minit, 30 minit, 60 minit, 90 minit dan 120 minit. Spektra FTIR polisakarida yang diambil sebelum dan selepas sinaran UV menunjukkan kerosakan ikatan kovalen dan dengan itu, peningkatan dalam keamatan kedua-dua getaran regangan O?H dan C?O. Oleh itu, peningkatan dalam aktiviti antioksidan yang diperhatikan dalam sampel yang dirawat berkait dengan perubahan yang dilihat dalam struktur molekul.

Article Details

How to Cite
Jamie Mei-Lin Kok, & Ching-Lee Wong. (2022). In vitro Properties of Methanol Extract and Sodium Alginate of Sargassum polycystum C. Agardh Brown Seaweed Collected from Malaysia. Tropical Life Sciences Research, 33(1), 55–76.
Original Article


Benzie I E F and Strain J J. (1996). The ferric reducing ability of plasma (FRAP) as a measure of “antioxidant power”: The FRAP assay. Analytical Biochemistry 239(1): 70–76.

Boonchum W, Peerapornpisal Y, Kanjanapothi D, Pekkoh J, Pumas C, Jamjai U and Vacharapiyasophon P. (2011). Antioxidant activity of some seaweed from the Gulf of Thailand. International Journal of Agriculture and Biology 13(1): 95–99.

Carballo J L, Hernández-Inda Z L, Pérez P and García-Grávalos M D. (2002). A comparison between two brine shrimp assays to detect in vitro cytotoxicity in marine natural products. BMC Biotechnology 2(1): 17.

Choi J I, Kim H J, Kim J H, Byun M W, Chun B S, Ahn D H and Lee J W. (2009). Application of gamma irradiation for the enhanced physiological properties of polysaccharides from seaweeds. Applied Radiation and Isotopes 67(7): 1277–1281.

CLSI (Clinical and Laboratory Standards Institute) (2006). Performance standards for antimicrobial susceptibility testing. CLSI Supplement M100-S16.

Wayne: CLSI. Cox S, Abu-Ghannam N and Gupta S. (2011). Effect of processing conditions on phytochemical constituents of edible Irish seaweed Himanthalia Elongata. Journal of Food Processing and Preservation 36(4): 348–363.

Devi G K, Manivannan K, Thirumaran G, Rajathi F A A and Anantharaman P. (2011). In vitro antioxidant activities of selected seaweeds from Southeast coast of India. Asian Pacific Journal of Tropical Medicine 4(3): 205–211.

Devi K P, Suganthy N, Kesika P and Pandian S K. (2008). Bioprotective properties of seaweeds: in vitro evaluation of antioxidant activity and antimicrobial activity against food borne bacteria in relation to polyphenolic content. BMC Complementary and Alternative Medicine 8(1): 38.

Fenoradosoa T A, Ali G, Delattre C, Laroche C, Petit E, Wadouachi A and Michaud P. (2010). Extraction and characterization of an alginate from the brown seaweed Sargassum turbinarioides Grunow. Journal of Appleid Phycology 22(2): 131–137.

Fertah M, Belfkira A, Taourirte M and Brouillette F. (2017). Extraction and characterization of sodium alginate from Moroccan Laminaria digitata brown seaweed. Arabian Journal of Chemistry 10(3): 707–714.

Grasdalen H, Larsen B, Smidsrød O. (1979). A p.m.r. study of the composition and sequence of uronate residues in alginates. Carbohydrate Research 68(1): 23–31.

Harbone J B. (1973). Phytocheical methods. London: Chapman and Hall Ltd.

Hwang E K, Park C S and Baek J M. (2006). Artificial seed production and cultivation of the edible brown alga, Sargassum fulvellum (Turner) C. Agardh: Developing a new species for seaweed cultivation in Korea. In 18th International Seaweed Symposium, Dordrecht: Springer, 25–31.

Ito H, Satsukawa M, Arai E, Sugiyama K, Sonoyama K and Kiriyama S. (2009). Soluble fiber viscosity affects both goblet cell number and small intestine mucin secretion in rats. Journal of Nutrition 139(9):1640–1647.

Ito K and Hori K. (1989). Seaweed: Chemical composition and potential food uses. Food Reviews International 5: 101–144.

Jaswir I, Asiyanbi-Hammed T T, Raha A R, Hammed A M and Nazaruddin R. (2014). Study on anti-bacterial potentials of some Malaysian brown seaweeds. Food Hydrocolloids 42(2): 275–279.

Jensen H M, Larsen F H and Engelsen S B. (2015). Characterization of alginates by nuclear magnetic resonance (NMR) and vibrational spectroscopy (IR, NIR, Raman) in combination with chemometrics. In Natural Products From Marine Algae: Methods and Protocols, Springer, 347–363.

Jeyaraman A, Gopalswamy S and Kasiviswanathan P. (2013). Pharmacognostical study and phytochemical evaluation of brown seaweed Sargassum wightii. Journal of Coastal Life Medicine 1(3):199–204.

Kausalya M and Rao G N. (2015). Antimicrobial activity of marine algae. Journal of Algal Biomass Utilization 6(1): 78–87.

Marimuthu J, Antonisamy, Essakimuthu P, Narayanan J, Anantham B, Tharmaraj R and Arumugam S. (2012). Phytochemical characterization of brown seaweed Sargassum wightii. Asian Pacific Journal of Tropical Disease 2(1): 109–113.

Matanjun P, Mohamed S, Mustapha N M and Muhammad K. (2009). Nutrient content of tropical edible seaweeds, Eucheuma cottonii, Caulerpa lentillifera and Sargassum polycystum. Journal of Applied Phycology 21(1): 75–80.

Nagasawa N, Mitomo H, Yoshii F and Kume T. (2000). Radiation-induced degradation of sodium alginate. Polymer Degradation and Stability 69(3): 279–285.

Noiraksar T and Ajisaka T. (2008). Taxonomy and distribution of Sargassum (Phaeophyceae) in the Gulf of Thailand. Journal of Applied Phycology 20(5): 963.

O'Halloran S A, Grimes C A, Lacy K E, Nowson C A and Campbell K J. (2016). Dietary sources and sodium intake in a sample of Australian preschool children. BMJ Open 6(2): e008698.

Ortega-Calvo J J, Mazuelos C, Hermosin B and Saiz-Jimenez C. (1993). Chemical composition of Spirulina and eukaryotic algae food products marketed in Spain. Journal of Applied Phycology 5(4): 425–435.

Pearson D. (1976). The chemical analysis of foods, 7th ed. Longman Group Ltd. Pérez M J, Falqué E and Domínguez H. (2016). Antimicrobial action of compounds from marine seaweed. Marine Drugs 14(3): 52.

Pharmacopoeia B. (2013). British pharmacopoeia commission London; the department of health. Social Services and Public Safety 1: 719–720.

Rajauria G and Abu-Ghannam N. (2013). Isolation and partial characterization of bioactive fucoxanthin from Himanthalia elongata brown seaweed: A TLCbased approach. International Journal of Analytical Chemistry 2013: 802573.

Rajauria G, Jaiswal A K, Abu-Ghannam N and Gupta S. (2010). Effect of hydrothermal processing on colour, antioxidant and free radical scavenging capacities of edible Irish brown seaweeds. International Journal of Food Science and Technology 45(12): 2485–2493.

Redmond S, Kim J K, Yarish C, Pietrak M and Bricknell I. (2014). Culture of Sargassum in Korea: Techniques and potential for culture in the US. Maine Sea Grant Publications. 32.

Rupérez P. (2002). Mineral content of edible marine seaweeds. Food Chemistry 79(1): 23–26.

Sathya R, Kanaga N, Sankar P and Jeeva S. (2017). Antioxidant properties of phlorotannins from brown seaweed Cystoseira trinodis (Forsskål) C. Agardh. Arabian Journal of Chemistry 10(Suppl. 2): S2608–S2614.

Subramanian V, Ganapathi K and Dakshinamoorthy B. (2015). FT-IR, 1 H-NMR and 13C-NMR Spectroscopy of alginate extracted from Turbinaria decurrens (Phaeophyta). World Journal of Pharmacy and Pharmaceutical Sciences 4(12): 761–771.

Torres M R, Sousa A P, Silva F E A, Melo D F, Feitosa J P, de Paula R C and Lima M G. (2007). Extraction and physicochemical characterization of Sargassum vulgare alginate from Brazil. Carbohydrate Research 342(14): 2067–2074.

Trease G E and Evans W C. (1983). Drugs of biological origin. Pharmacognosy, 12th ed. United Kingdom: Balliere Tindal, 309–540.

US EPA. (1996). SW-846 reference methodology: Method 6010B. Inductively coupled plasma–atomic emission spectrometry, Revision 2, Washington, DC, p. 25.

Wasikiewicz J M, Yoshii F, Nagasawa N, Wach R A and Mitomo H. (2005). Degradation of chitosan and sodium alginate by gamma radiation, sonochemical and ultraviolet methods. Radiation Physics and Chemistry 73(5): 287–295.