Poster Topical Area: Dietary Bioactive Components

Location: Hall D

Poster Board Number: 276

P08-018 - Antioxidant capacity of Maine brown edible seaweeds and the anti-inflammatory activity in lipopolysaccharide-stimulated RAW264.7 macrophages

Monday, Jun 11
8:00 AM – 3:00 PM

Objective: Chronic inflammation is an underlying factor in health conditions such as diabetes and cardiovascular disease. Seaweeds are a group of photosynthetic macro-algae which are known to contain anti-inflammatory bioactive compounds.  The objective of this study is to investigate the antioxidant capacity and the potential anti-inflammatory activity of fresh and commercially-available dried seaweed (Ascophyllum nodosume – AS, Laminaria digitata – LD and Alaria esculenta – AE) harvested in Maine.

Methods: Commercially dried and freeze-dried seaweeds (fresh) were extracted with 80% methanol. Total phenolics were quantified using the Folin-Ciocalteu assay. The antioxidant capacity was evaluated with 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. Cytotoxicity of seaweed extracts at different levels was examined via MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) assay. The anti-inflammatory activity of seaweed was assessed by the inhibition of nitric oxide production in the lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages.

Results: Compared to commercially dried seaweeds, fresh seaweeds contained higher amounts of phenolic compounds and exhibited stronger antioxidant capacity. Fresh AS had the highest phenolic content (21.94 mg gallic acid/g seaweed) and strongest antioxidant capacity (16.33 mg gallic acid/g seaweed). The concentrations of extracts at 600 µg/mL did not lower the viability of RAW264.7 cells. AS exhibited the highest inhibitory activity of nitric oxide production in LPS-stimulated macrophages. At 600 µg/mL, AS extract inhibited nitric oxide production by 39.8%. The inhibitory effects on nitric oxide production of LD and AE were minor.

Conclusions: AS exhibited higher antioxidant capacity and better anti-inflammatory potential comparing to LD and AE. Fresh seaweeds had higher bioactivity than commercially dried seaweeds.

CoAuthors: Angela Myracle, MPH,PhD – University of Maine

Xue Du

PhD candidate
University of Maine
Orono, Maine