Extraction and Purification of Functional Proteins from Marine Macroalgae for Food Application

Meital Kazir, Biotechnology and Food Engineering, Technion – Israel Institute of Technology, Haifa, Israel

In recent decades there is a steady increase in the World population due to a global decrease in mortality and increase in birth rate. Therefore, there is also a growth in demand for food, which requires seeking new ways to increase food production. With decreasing available land and fresh water resources, the oceans are an attractive alternative for basing agriculture (mariculture) intended for human consumption.

Marine macroalgae (seaweeds) contain a wide range of nutrients, many of which have significant importance in human nutrition and great economic potential for the food industry. Species of the green genus Ulva spp. and the red genus Gracilaria spp. are promising candidates for such mariculture since they are known for their fast growth rate and nutritional benefits, including edible proteins. Literature sources indicate that these species are mostly rich in carbohydrates and proteins. Along with these two major fractions, the algae contain important lipids and micronutrients such as minerals, and phytochemicals. Gracilaria and Ulva species mainly grow in different months, so for optimal year-round high yield protein production, a combination of those two complementary species would be ideal.

For a start, we are focusing on the extraction of algal proteins, which consist of significant amounts of essential amino acids. We have so far managed to obtain an algal protein concentrate (APC) from Ulva and from Gracilaria, containing 70 and 86% protein respectively, using only food applicable procedures.

Protein concentrates extracted from Ulva and Gracilaria, seem to be a promising new and renewable source for human nutrition. The concentrates have a relatively high antioxidant activity, compared to known proteins, and are highly digestible under simulated gastro-intestinal digestion.

Currently, we are investigating and characterizing the functionality of these new and renewable food proteins, which are expected to contribute to the development of novel food products.