Abstract
Seaweeds are important sources of carotenoids, and numerous studies have shown the beneficial effects of these pigments on human health. In the present study, Himanthalia elongata brown seaweed was extracted with a mixture of low polarity solvents, and the crude extract was separated using analytical thin-layer chromatography (TLC). The separated compounds were tested for their potential antioxidant capacity and antimicrobial activity against Listeria monocytogenes bacteria using TLC bioautography approach. For bio-autography, the coloured band on TLC chromatogram was visualized after spraying with DPPH and triphenyl-tetrazolium chloride reagents which screen antioxidant and antimicrobial compounds, respectively, and only one active compound was screened on the TLC plate. Preliminary identification of this active compound was done by comparing its colour and R f (retention factor) value with the authentic fucoxanthin standard. Further, the active compound was purified using preparative TLC. This purified compound showed a strong antioxidant (EC50: 14.8 ± 1.27 µg/mL) and antimicrobial (inhibition zone: 10.27 mm, 25 µg compound/disc) activities, which were examined by DPPH scavenging and agar disc-diffusion bioassay, respectively. The bioactivity shown by the purified compound was almost similar to the fucoxanthin standard. The characteristic UV-visible and FT-IR spectra of the purified active compound completely matched with the standard. Hence, the main active compound in H. elongata was identified as fucoxanthin.
Highlights
Compared to terrestrial plants, seaweeds are an untapped resource offering substantial potential for the isolation of original natural ingredients of interest for food and health purposes
A rapid and reliable thin-layer chromatography (TLC)-based approach was applied to isolate and purify the fucoxanthin pigments for the first time from Himanthalia elongata brown Irish seaweed. This approach includes the extraction of seaweed with previously optimized low polarity solvent mixtures, isolation of crude extract using analytical thin layer chromatography (TLC), biological screening of the extract for its antioxidant and antimicrobial activities using TLC bioautography, and purification of active compounds by preparative TLC
Brown seaweed used in the present study was Himanthalia elongata which was purchased from Quality Sea Veg., Co Donegal, Ireland
Summary
Seaweeds are an untapped resource offering substantial potential for the isolation of original natural ingredients of interest for food and health purposes. This pigment belongs to the group of xanthophyll, and recent reports suggest that fucoxanthin has several biological properties such as antioxidant, antimicrobial, antiobesity, and anticancer activities [7] This pigment has been isolated and identified from edible brown seaweeds such as Sargassum siliquastrum, Hizikia fusiformis, and Undaria pinnatifida [8,9,10]. A rapid and reliable TLC-based approach was applied to isolate and purify the fucoxanthin pigments for the first time from Himanthalia elongata brown Irish seaweed This approach includes the extraction of seaweed with previously optimized low polarity solvent mixtures, isolation of crude extract using analytical thin layer chromatography (TLC), biological screening of the extract for its antioxidant and antimicrobial activities using TLC bioautography, and purification of active compounds by preparative TLC. To the best of our knowledge, this is the first time this compound has been biologically screened, isolated, and purified from H. elongata seaweed
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
