Preprint volume - SIBM

Fatty acids (%)
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50
40
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Pre-print Volume – Oral presentations
Topic 3: INTEGRATED COASTAL ZONE MANAGEMENT
14:0 myristic 16:0 palmitic 18:0 stearic 18:1ω9 oleic 18:2ω6
linoleic
Gracilaria dura Gracilaria gracilis
Gracilariopsis longissima Cystoseira barbata
Cladophora rupestris Chaetomorpha linum
18:3ω3
linolenic
18:3ω6 γ
linolenic
Fig. 2 - Fatty acids composition of the studied species (C. linum data are from Biandolino and Prato,
2006).
Composizione in acidi grassi (per C. linum vedi Biandolino e Prato, 2006).
Tab. 1 – Lipidic extracts antimicrobial activity. Numbers report the inhibition diameter in cm.
Attività antimicrobica degli estratti. Il diametro di inibizione è riportato in cm.
Microbial strains C. barbata G. gracilis Gs. longissima G. dura C. linum C. rupestris
Candida albicans 0 0 0 0 0 0
Candida famata 0 0 0 0 0 0
Candida glabrata 0 0 0 0 0 0
Pseudomonas aeruginosa 0.9 0 0 0 0 0
Salmonella sp. 0 0 0 0 0 0
Enterococcus sp. 0 0 0 0 0 0.8
Streptococcus agalactiae 0 0 0 0 0 0.8
Vibrio salmonicida 0 0.8 0.8 0 0 0
Vibrio fluvialis 0 0.8 0.8 0.8 0 0
Vibrio vulnificus 0.6 0 1.5 0 1.2 0
Vibrio cholerae non –O1 0 0.8 1.0 0.8 0 0.8
Vibrio alginolyticus 3.5 0 2.5 1.0 0 0
Conclusions –1) All the tested species are suitable for ammonium removal even when
they are N-replete which would probably represent the usual conditions in aquaculture
farm effluents; 2) The several health-promoting and essential fatty acids and the good
levels of ω3 found in the studied seaweeds would produce fish rich in ω3 so
contributing to balance the ω3/ω6 ratio in humans. 3) All the tested species extracts
showed a high antimicrobial activity at least against one of the most common
pathogenic Vibrio species tested including those which cause diseases in many farmed
species. Fish, often stressed by the farming high density, fall in more easily; this causes
high mortality which strongly affects production. The addition of the examined
seaweeds to feed could reduce the administration of antibiotics so contributing to the
reaching of a “biological aquaculture”.
41 st S.I.B.M. CONGRESS Rapallo (GE), 7-11 June 2010
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20:4ω6 ARA 20:5ω3 EPA 22:6ω3 DHA