GC-MS Metabolite Profiling, Antibacterial, Antidiabetic and Antioxidant Activities of Brown Seaweeds, Sargassum wightii Greville Ex J. Agardh, 1848 and Stoechospermum marginatum (C. Agardh) Kützing 1843

Abstract

Objectives: The present study focuses on antibacterial, antidiabetic and antioxidant activities of methanolic extracts of brown seaweed Stoechospermum marginatum (SMME) and Sargassum wightii (SWME). Methods: The antibacterial activities of the seaweed extracts were determined by agar well diffusion method. Phytochemical, antioxidant and antidiabetic activity of the selected seaweed extracts were performed. Results: The phytochemical analysis of SMME and SWME has confirmed the presence of fixed oil, fat, tannin, flavonoids, alkaloids, steroids, phenol compounds, saponin etc. The SWME showed maximum activity against Staphylococcus aureus and minimum activity against Escherichia coli. And the SMME has shown moderate activity against S. aureus. The antidiabetic efficacy of SWME revealed the maximum effect with the inhibitory concentration value (IC 50 : 58.36 μg/mL) followed by SMME. The SWME has showed the highest scavenging property in all the tested assays (DPPH, FRAP and H 2 O 2 ) in relation to the control, ascorbic acid. The bioactive metabolites of the extracts were chemically characterized by FTIR and GCMS analyses. GC-MS analysis of SWME revealed the presence of a major chemical compound, hexadecenoic acid, methyl ester (13.35%) which might be responsible for the recorded activity. The FTIR spectrum analyses of crude extracts revealed the presence of alkyl halides, alkanes, amides, aromatics and carboxylic acids. Hence, the present study could form a base-line for the effective biomedical utilization of the seaweed, S. wightii.

GC-MS based metabolomics and lipidiomics analyses of selected freshwater green macroalgae

“…The GC-MS analysis in methanolic extracts of brown seaweed Sargassum wightii indicated the presence of 5-Isopropyl-6-methyl-hepta-3,5-dien-2-ol [15]. Thujone and thujol are isolated from Salviae aetheroleum extract, they are neurotoxic and abortive substances [16].…”

Profiling of Peak Intensity and Standard Deviation of Metabolites in Industrially Important Red Seaweed Gracilaria dura (Rhodophyta) by 1H NMR Spectra for Benchmarking

“…The analytical platforms being routinely used in metabolomics studies includes GC/MS, LC/MS, and NMR spectroscopy. It may be noted that 20 metabolites were reported from Sargassum wightii, 25 23 from Jania rubens, 26 16 from Dictyota dichotoma, 27 and 13 from G. dura; 24 175 metabolites were reported from four brown, five red, and two green algae species. 17 Nevertheless, compared to terrestrial plants, the database for seaweed metabolite is rudimentary and represented by only 1110 metabolites (SWMD; http://www.swmd.co.in/, 2021).…”

“…The analytical platforms being routinely used in metabolomics studies includes GC/MS, LC/MS, and NMR spectroscopy. It may be noted that 20 metabolites were reported from Sargassum wightii, 23 from Jania rubens, 16 from Dictyota dichotoma, and 13 from G. dura; 175 metabolites were reported from four brown, five red, and two green algae species .…”

Facile green synthesis of nanoparticles from brown seaweed Sargassum wightii and its biological application potential

“…The antibacterial activities of the SW-AE and SW-AgNPs were evaluated by the agar well diffusion method [28]. Nutrient agar plates containing 15 ml of solidified medium were inoculated with 100 µl of overnight bacterial culture of Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Shigella flexneri, Bacillus subtilis, Bacillus cereus and Enterococcus faecalis.…”