Abstract:
The consumption of seaweeds has increased over the recent past However, certain effects of seaweeds
are yet to be investigated. The objective of the present study was to evaluate the safety and the effects of
feeding aqueous extracts of Sargassum crassifolium and Ulva fasciata, on some selected haematological
parameters including differential blood count, packed cell volume (PCV), concentrations of total serum
protein, serum aspartate transaminase (AST) and serum alanine transaminase (ALT) in laboratory mice.
Two groups of six mice were orally administered with aqueous extracts of the two seaweed species,
separately. A dose of 454.5mg/kg body weight was given once a day for 9 days and observed up to 12
days. A control group (n=5) was also maintained without treatment. Both extracts did not show any toxic
effects in an acute toxicity test There was a significant increase (p<0.05) in the neutrophil count in mice
12 days after commencing treatment with aqueous extracts of Ulva fasciata (n=5, 31.55% ± 4.1%)
compared with the control (n=5,19.0% ± 3.4%). However, the consequent decrease in the monocytes and
lymphocytes with the Ulval extract was not significant (p>0.05) 12 days post-treatment. There was no
significant (p>0.05) change in the total serum protein concentration, at the end of the study period. Serum
concentrations of AST and ALT did not show significant changes (p>0.05) after feeding the extracts of Ulva
fasciata and Sargassum crassifolium. In conclusion, aqueous extracts of Sargassum crassifolium and Ulva
fasciata did not exhibit any toxicity in laboratory mice, in vivo, at the dose tested.
