Some toxinological aspects of Aurelia aurita (Linné) from the Mexican Caribbean

Abstract

Aurelia aurita is a scyphozoan, abundant in the Mexican Caribbean during summer. Although usually innocuous, there is evidence of it causing harm to humans. This work investigates the biological activities of crude and fractionated extracts of A. aurita. Live specimens were collected between July and September 1999 from the Mexican Caribbean. The tentacular margin was dissected immediately and frozen at -50ºC. A nematocyst suspension was prepared, discharged, and the supernatants lyophilized. Hemolytic assay was performed with lyophilized crude extract on bovine, sheep, and human red blood cells. Erythrocyte sensitivity to the toxin was ranked in descending order: human, sheep, and bovine. Toxic activity on Artemia nauplii was evaluated using the same crude extract for different exposure periods (3, 5, and 10 hours); only 48 and 72 hour old Artemia nauplii showed 50% mortality. Partial toxin purification was completed by sequential liquid chromatography using three gels (Sephadex G-200, DEAE Sephadex A-50, and Sephadex G-100). Intramuscular neuroactivity was detected in the crab Ocypode quadrata for two partially purified fractions. These fractions were found to have molecular weight components of 66 and 45 kDa, respectively

Gill cell toxicity of northern boreal scyphomedusae Cyanea capillata and Aurelia aurita measured by an in vitro cell assay

“…Size exclusion chromatography and gel electrophoresis of the bioactive venom were performed by Segura-Puertas et al (2002) and indicated that the toxic proteins were 45 and 66 kDa which matches the detected values in the present investigation. The broad molecular weight range (Fig.…”

“…A general lytic effect was observed when red-tide flagellate species were treated with A. aurita autolysate (Hiromi et al, 1997). Segura-Puertas et al (2002) found that dermonecrotic activity, haemolysis and neurotoxicity were caused by exposure to whole venoms of tentacular margins.…”

“…There are only a few studies concerning the toxic potential of A. aurita, and no detailed biochemical information about the composition of the venom is available (Burnett et al, 1988;Radwan et al, 2001;Segura-Puertas et al, 2002).…”

Separation and analysis of different types of nematocysts from Cyanea capillata (L.) medusae

“…and suggested that different diets during the growth of the medusae may be responsible for the different frequencies of nematocyst types. Furthermore, Burnett et al (1988), Radwan et al (2001), andSegura-Puertas et al (2002) suggested that the variation in stinging potency and toxic potential in the medusae they studied was related to their different habitat conditions. The objective of this study was to compare the cnidom and the capsule contents of separated nematocysts of C. capillata (L.) medusae collected from the North Sea and from the Baltic Sea.…”

“…Many species of jellyfish are known to cause injuries or even fatalities by stinging (Burnett et al, 1988;Fenner, 1998;Segura-Puertas et al, 2002;Tibballs, 2006;Š uput, 2009). Despite the wide-spread concern about the damage caused by jellyfish stings to the tourism and aquaculture industries (Doyle et al, 2008), surprisingly little is known about the effect of various environmental factors on the toxins of the medusae.…”