Commercially Exploited Seaweed Species in Africa: Occurrences, Chemical Composition, Current Value Chain and Opportunities for Value Addition

Abstract

Africa has a wide range of coastal environments that support a diverse array of seaweed species. Despite this, only a few African countries are involved in the commercial harvesting and value addition of seaweed. Instead, most of the seaweed harvested in Africa has been exported as dried seaweed for value addition. This review discussed the different seaweed species commercially exploited in Africa, their nutritional composition, their current and potential uses as food, paying attention to food safety aspects regarding heavy metals and microbiological safety, and their use as animal feed ingredients and as sources for the production of polysaccharides, proteins, and biostimulants. It was noted that many factors limit seaweed value addition in Africa, including limited access to financial capital, a lack of seaweed research activities, a lack of seaweed storage and processing facilities, limited technical capacity, and weak domestic markets. Thus, in this review, the authors suggested that seaweed value addition in Africa should be regional (East, South, West, and North Africa), driven by species largely grown in those regions. These suggestions can leverage existing value chains across different regions in Africa. To achieve this, more regional cooperation among countries producing similar species is necessary, knowledge sharing on best farming practices, and more research on chemical composition, safety (microbial, heavy metals, microplastics), and efficacy, as well as funding and policy for human capital skill development and the technical skills necessary for seaweed processing.