Abstract
Seaweeds provide important macronutrients for marine herbivores and potential for aquaculture. However, the nutritional content of most New Zealand seaweeds is undocumented. Here, the nutritional composition of eleven common, littoral seaweed species in northeastern New Zealand was examined using proximate composition analysis. Overall, red seaweeds were highest in protein and insoluble fibre, brown seaweeds were highest in lipids and soluble carbohydrates, and green seaweeds were highest in moisture and ash. More specifically, red seaweeds Asparagopsis armata and Pterocladiella capillacea were highest in protein, while Corallina officinalis was highest in ash and much lower in other macronutrients. Brown seaweeds Carpophyllum maschalocarpum and Cystophora retroflexa were highest in soluble carbohydrates, C. retroflexa was highest in lipids, and Xiphophora chondrophylla was highest in insoluble fibre. Across all species, green seaweeds Codium fragile and Ulva cf. lactuca were highest in moisture. In summary, this study provides a baseline of the nutritional composition of various common seaweeds in northeastern New Zealand, encourages research examining drivers of variability in nutritional composition and highlights commercial opportunities in New Zealand's burgeoning seaweed sector.