Isolation and characterisation of bioactive components from Saccharina latissima and Alaria esculenta and their effect on proliferation and migration of intestinal epithelial cells (RTgutGC) in vitro
Year: 2018
Type: dissertation
Abstract: The human population is projected to grow to 9.6 billion by 2050. This means increased demand for food, pharmaceuticals and feed for fish and farm animals. There is a high focus on meeting these demands by developing novel and sustainable feed ingredients and additives from new types of biomasses. Norway has a long coastline and good opportunities to cultivate brown macroalgae. The nutritional value of brown macroalgae is relatively low, but can be upgraded through novel processing methods. However, they are also a resource known to contain a wide variety of bioactive polysaccharides beneficial to health. These compounds are subject to species- and seasonal variations and it is important to obtain more knowledge about the chemical composition, optimise the methods for extraction and isolation, and to examine the bioactivity of such compounds. The aim of this thesis was to extract, isolate and characterise the bioactive components, laminarin and fucoidan, from two species of brown macroalgae, Saccharina latissima and Alaria esculenta. To achieve this, a solvent based acid extraction was applied, followed by a step-wise filtration of the extract using an ultrafiltration system to separate laminarin and fucoidan based on their molecular weight. The chemical composition in the native macroalgae and in the isolated fractions was analysed for dry matter, ash and elements, and the carbohydrates were analysed as the amount of monosaccharides released after two different methods of acid hydrolysis. The results indicated that the molecular weight of laminarin and fucoidan in the two species of macroalgae differed from one another. But, it was possible to isolate a laminarin and fucoidan fraction and test their bioactivity. Macroalgae is potentially an ingredient in feeding trials and is hypothesised to stimulate repair of the mucosal barrier. The bioactivity was tested in a wound healing assay using intestinal epithelial cells from rainbow trout. Laminarin stimulated cell migration and proliferation with increasing concentrations, whilst fucoidan seemed to prevent cell growth. These results give an indication of the immunostimulatory effects of these compounds and the potential use of laminarin in the promotion of intestinal cell migration and proliferation, or fucoidan to inhibit cell proliferation and growth e.g., as an anticancer reagent.
Author: Ida Steine Oma
Language: English
Subfield: Aquatic Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W2905735145