Harmful and toxic algae
Abstract
The chapter provides basic facts about harmful and toxic algae. It also discusses the conditions that stimulate their occurrence, different types of harmful and toxic algal blooms and their effects to fish and marine environment. The different strategies in coping with the problem of harmful and toxic algal blooms are also discussed.
Citation
Caturao, R. D. (2010). Harmful and toxic algae. In G. D. Lio-Po & Y. Inui (Eds.), Health Management in Aquaculture (2nd ed., pp. 170-182). Tigbauan, Iloilo, Philippines: Aquaculture Department, Southeast Asian Fisheries Development Center. http://hdl.handle.net/10862/3243
Publisher
Aquaculture Department, Southeast Asian Fisheries Development CenterSubject
Type
Book chapterISBN
9718511458Collections
Related items
Showing items related by title, author, creator and subject.
-
Book chapter
Harmful and toxic algae
- In GD Lio-Po, CR Lavilla & ER Cruz-Lacierda (Eds.), Health Management in Aquaculture, 2001 - Aquaculture Department, Southeast Asian Fisheries Development CenterThe chapter provides basic facts about harmful and toxic algae. It also discusses the conditions that stimulate their occurrence, different types of harmful and toxic algal blooms and their effects to fish and marine environment. The different strategies in coping with the problem of harmful and toxic algal blooms are also discussed. -
Book chapter
Bacteria and toxin isolated from the dinoflagellate Pyrodinium bahamense var. compressum and production of monoclonal antibodies and diagnostic kits to monitor red tide and toxic mussels
- In T Bagarinao (Ed.), Research Output of the Fisheries Sector Program, 2007 - Bureau of Agricultural Research, Department of AgricultureSix bacterial isolates obtained from the red tide dinoflagellate Pyrodinium bahamense var. compressum were found to be toxic. The most toxic isolate MM-11 was cultured, characterized, and identified to be Micrococcus luteus. MM-11 and M. luteus had similar DNA bands on agarose gel, and contained 70.0–75.5% mole G+C. Several Micrococcus species were isolated from pure culture and field samples of Pyrodinium and from red tide affected mussels. MM-11 and the other Micrococcus isolates tested positive for saxitoxin. MM-11 was grown on seawater agar; peak cell density of 1.36 x 1010 cells/ml occurred after 3 days of incubation. Toxin production was directly proportional to cell density. The crude toxin from the optimized culture of MM-11 resulted in death of mice in only 1.8–2.4 min, equivalent to a toxicity of 5.9–13.4 mouse units. MM-11 was inoculated into healthy mussels and yielded bacterial isolates that had characteristics of MM-11, and extracts of toxin similar to MM-11 toxin. Mice injected with extracts from the inoculated mussels showed symptoms of paralytic shellfish poisoning (dyspnea 12–15 min after injection), but did not die. Partially purified extracts from red tide affected mussels killed mice in 3.4 min, equivalent to a toxicity of 3.4 mouse units. Addition of 5, 25 and 50% coconut milk to this toxin extract reduced the toxicity to only 34%, 29%, and 25% of that without coconut milk. The ELISA test similarly showed reduction of saxitoxin concentration from 4.78 g toxin/g at 5% added coconut milk to 3.62 g toxin/g at 50% added coconut milk. PSP toxins were extracted from bacteria and red tide affected mussels. The 24 purified extracts of MM-11 toxin were shown by mouse bioassay to have concentrations from 0.6 to 71.6 μg toxin/g bacteria. Green mussels sampled from Bataan and Zambales during incidence of red tides from 1994 to 1998 contained lower amounts of toxin per unit weight than the bacterial extracts. Analysis of the MM-11 toxin by HPLC-fluorometry showed two fractions similar to those of standard gonyautoxin 1 and gonyautoxin 3. -
Conference paper
Effects of coconut milk and brown sugar on crude toxins from mussels exposed to Pyrodinium bahamense var. compressa
- In JL Maclean, LB Dizon & LV Hosillos (Eds.), The First Asian Fisheries Forum: Proceedings of the First Asian Fisheries Forum, Manila, Philippines, 26-31 May 1986, 1986 - Asian Fisheries SocietyDuring a red tide episode caused by Pyrodinium bahamense var. compressa in Western Samar, Philippines in 1983, those who were taken ill after ingesting the green mussel, Perna viridis , resorted to drinking coconut milk (gata , Pilipino) with brown sugar or unpurified sugar lumps (tagapulot , Pilipino) as a temporary palliative, pending medical attention. Many victims felt relief after the drink. Crude toxins (CT) were extracted from P. viridis exposed to Pyrodinium using 0.1 N HCl and reacted with either or both 5% coconut milk (CM) and 5% brown sugar (BS) for an hour. The CT, CM, BS, CT + CM, CT + BS, and CT + CM + BS were assayed in duplicates for saxitoxin using the standard mouse toxicity test. CT with initial toxicity of 2,114 MU/100 g meat was substantially detoxified after a one-hour reaction. In CT + CM, the toxicity was 664 MU/100 g; in combined CT + CM + BS the toxicity was 1,005 MU/100 g. In medium- (436-563 MU/100 g) and low-toxicity extracts (160-231 MU/100 g) no deaths in mice were recorded within one hour of injection.
