Composition, Enzymes Analysis and Retraction Time of Columellar Muscles of Giant African Land Snail (Archachatina marginata) in Response to External Stimuli

Abstract

With the aid of columellar muscle, snails retract the soft part into the shell when disturbed. The response time of three Giant African Land Snail (GALS) species: Archachatina marginata, Achatina achatina and Achatina fulica to touch and sodium chloride (NaCl) solution was examined. Chemical composition (protein, glucose, lipids, K⁺, Na⁺ ) and enzyme activities (amylase, cellulase, á glucosidase and lipase) in the columellar muscle of the three snail species were also investigated. Flame photometry was used to analyze the ions while spectrophomerty methods were employed for enzymes assay. A.achatina responded significantly faster (6.00 seconds) than other two snail species when stimulated by touch. The columellar muscle of A. achatina had the highest concentration of glucose and lipids(8.3mg/dl and 46.9mg/dl respectively) while A. marginata had the least. Na⁺ and K⁺ concentrations of A. achatina columellar muscle were lower than those of other two species. The four enzymes assayed were detected in the columellar muscles of the three snails at varying levels. A. achatina recorded higher á glucosidase (0.71 Abs /min) and cellulase (1.28 Abs/min ) activities than other two species. It can be concluded that the quicker response of A.achatina to environmental factors lies in its columellar properties.

Keywords: giant African Land Snails; enzyme activities; sensory physiology