Isolation and characterization of Carnobacterium maltaromaticum from the intestine of sea cucumber Acaudina molpadioides

Abstract

Aims: Acaudina molpadioides is a highly valued sea cucumber that is distributed on the muddy shores on the west coast of Peninsular Malaysia and is considered a local delicacy. Carnobacterium maltaromaticum is a type of lactic acid bacteria commonly found in meat, fish and dairy products and is usually isolated from the intestine of aquatic animals. It is scarcely reported from the intestine of A. molpadioides. This species is known to be pathogenic in fish but unknown in humans. The aim of this study was to isolate and characterize C. maltaromaticum from the intestine of A. molpadioides. Methodology and results: Using standard methods, the strains were tested for their biochemical and carbohydrate properties, antibiotic sensitivity tests, temperature sensitivity tests and molecular identification. A total of 1642 isolates were obtained, out of which three strains were chosen as they were catalase-negative, Gram-positive bacilli, negative to IMViC tests, γ-hemolysis, and positive to lactose and glucose tests. Molecular identification was made to strain AM47e and 16S rRNA genes sequence showed 99.93% similar to C. maltaromaticum. The sequence was submitted to GenBank as Carnobacterium maltaromaticum (Accession No: MZ 934727). The optimum growth temperature for the strains was 37°C and the antibiotic susceptibility showed they were sensitive to tetracycline, ampicillin and meropenem. Conclusion, significance and impact of study: In conclusion, C. maltaromaticum can be isolated from the intestine of A. molpadioides with the potential of the probiotic applications and less potential vulnerability for consumers.