Kelp are large seaweeds (algae), belonging to the brown algae and classified
in the order Laminariales. There are about 30 different genera. Some species can
be very long and form kelp forests.
Kelp nutritional study by: School of Nutrition, Faculty of Community Services,
Ryerson University, 350 Victoria St., Toronto, Ont., Canada M5B 2K3. email@example.com
Dietary Laminaria and Porphyra sp. have been reported to
reduce the risk of intestinal or mammary cancer in animal studies. Algal
anticarcinogenicity may involve effects on cell proliferation and antioxidant
activity. Thus, in the present study, we evaluated the effect of red alga, dulse
(Palmaria palmata) and three kelp (Laminaria setchellii, Macrocystis
integrifolia, Nereocystis leutkeana) extracts on human cervical adenocarcinoma
cell line (HeLa cells) proliferation using the MTT
(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay. The
1-butanol soluble fractions from the methanol extracts of these algae were also
evaluated for reducing activity and total polyphenol content. After 72 h
incubation, HeLa cell proliferation was inhibited (p<0.05) between 0% and 78% by
P. palmata; 0% and 55% by L. setchellii and 0% and 69% by M. integrifolia and N.
leutkeana at 0.5-5mg/mL algal extract. Algal extract reducing activities were as
follows: P. palmata>M. integrifolia>L. setchellii>N. leutkeana; and total
polyphenol contents were: P. palmata>M. integrifolia=N. leutkeana>L. setchellii.
The antiproliferative efficacy of these algal extracts were positively
correlated with the total polyphenol contents (p<0.05), suggesting a causal link
related to extract content of kelp phlorotannins and dulse polyphenols including
mycosporine-like amino acids and phenolic acids.