Diseases, metals and bioactive compounds in seaweeds of Bangladesh

Abstract

Seaweeds are photoautotrophic multi-cellular macro-algae and play a vital role in livelihoods by providing employment opportunities and food supply. Bangladesh is a maritime country with vast coastal and marine habitats which processes a suitable habitat for seaweed farming. To make the seaweed industry profitable in Bangladesh it is important understand the diseases, metal pollution, bioactive compounds and proximate compositions of seaweeds. Therefore, this study aimed to understand the status of diseases, metal pollution, bioactive compounds and proximate compositions in five commercially important species in Bangladesh. Samples were collected from 20 seaweed farms from the south east coastal area of Bangladesh. We encountered 7 types of diseases in the collected seaweed samples. Occurrences of epiphytes were found as the most common disease in the seaweeds of Bangladesh (9%). Seaweed samples contained metals, however their concentrations were found below the threshold level for human consumptions (average Hg: Se ratio and total health quotient were found 0.10 and 0.25, respectively). Collected seaweed samples were found highly nutritive (carbohydrate= 23 to 32%, protein=12 to 26%, fat = 0.1 to 0.4% and fiber = 2.6 to 3.5%). In addition, mean total antioxidant capacity, carotenoids, 2, 2-Diphenyl-1-picrylhydrazyl and total phenolic content in seaweeds were found between 19 to 20.6 mg AAE/g, 31.2 to 32.3 mg/g, 71.4 to 74.4 % and 10.6 to 12.2 mg GAE/g, respectively. Our study indicates that seaweeds of Bangladesh have great potentiality for local consumptions as well as foreign export.