Bacteria and digestive enzymes in the alimentary tract of the giant African land snails, Archarchatina marginata and Achatina achatina

Abstract

A study was carried out to investigate the bacteria flora in the gut of the Giant African Land Snails (GALS), Archarchatina marginata and Achatina achatina. Microflora cultures from snail gut contents were prepared to isolate and identify microorganisms within the snail digestive tract. Enzyme assays were carried out on a few of the microorganisms to determine the presence and level of enzymatic activities. Results showed that a wide range of bacteria inhabit the alimentary tract of GALS. Bacteria isolates from the stomach (Bacillus cereus and Pseudomonas syringae) and mouth regions (Aeroccus viridians and Azobacter chroococcum) in the two species of GALS effectively digested starch, cellulose and casein. However, Bacillus species from the stomach region in A. achatina exhibited the highest enzymatic activities for cellulase (10.00 μmol/min/ml at 18 h), protease (23.97 μmol/min/ml at 18 h) and amylase (9.56 μmol/min/ml at 24 h) during incubation. Consequently, results from the present study confirmed that amylolytic, cellulolytic and proteolytic bacteria within the digestive tract of the two species of GALS do aid in the snail's digestive processes.

Keywords: Microorganisms, snail gut, enzyme activity and Giant African Land Snails