effects of selected cultivation conditions on the carrageenan characteristics of Kappaphycus alvarezii (Rhodophyta, Solieriaceae) in Ubatuba Bay, São Paulo, Brazil

• Published in: Journal of applied phycology Vol. 19; no. 5; pp. 505 - 511
• Main Authors: Hayashi, Leila, Oliveira, Eurico C, Bleicher-Lhonneur, Genevieve, Boulenguer, Patrick, Pereira, Ricardo T. L, von Seckendorff, Roberto, Shimoda, Viviane T, Leflamand, André, Vallée, Patrick, Critchley, Alan T
• Format: Journal Article
• Language: English
• Published: Dordrecht : Springer Netherlands 01.10.2007
• Subjects: Brackish; carrageenan; Eucheumatoid species; Kappaphycus alvarezii; macroalgae; mariculture; Marine; Phycocolloid; Rhodophyta; Solieriaceae; ASW, Brazil, Sao Paulo, Ubatuba Bay
• ISSN: 0921-8971; 1573-5176
• DOI: 10.1007/s10811-007-9163-x

The yield and the quality of carrageenan depend, among other things, on the cultivar or strain and on the cultivation and processing techniques. This work presents carrageenan yields and some properties of Kappaphycus alvarezii under selected cultivation conditions i.e. cultivation period, depth and planting density. Growth rates (GR) ranged from 5.2-7.2% day-¹, with the highest GR at 28 days, at 0-0.5 m depth, and planting density of 12 and 8.4 plants m-². Highest productivity was observed in samples after 44 and 59 day cultivation period, which were grown at 0-0.5 m depth, and a planting density of 24 plants m-². Carrageenan yields, iota fraction, viscosity, molecular weight and gel strength were measured. A cultivation period of 28 days during the winter had a significant higher carrageenan yield, while samples from 59 days showed a significantly higher iota fraction. Carrageenan also presented an increasing molecular weight under longer cultivation periods. A similar trend was observed for viscosity and gel strength. All samples cultivated in Brazil gave higher values when compared to a K. alvarezii commercial reference sample, with the exception of carrageenan yield values, which were lower in this study. Taking into account all parameters, the culture condition which provided the best carrageenan from a commercial perspective were 45 days of cultivation, growing at the surface, with a planting density of 12 plants m-². Considering that this study was performed in the least favorable season (winter), these results indicate that the site is suitable for the implementation of commercial cultivation.