Phenotypic Characterization of Intestinal Bacteria Isolated from Coconut Crabs (Birgus latro) on Liwo Island North Maluku

Et Al., Murhum

doi:10.21608/ejabf.2025.409516.6320

Phenotypic Characterization of Intestinal Bacteria Isolated from Coconut Crabs (Birgus latro) on Liwo Island North Maluku

Document Type : Original Article

Author

Murhum et al.

10.21608/ejabf.2025.409516.6320

Abstract

The coconut crab (Birgus latro) is a terrestrial crustacean species known for its unique dietary habits and ecological significance in island ecosystems. This study aims to isolate and characterize intestinal microorganisms from coconut crabs collected from Liwo Island, North Maluku, Indonesia. A total of nine microbial isolates were obtained using traditional culture-based methods. Morphological characterization, Gram staining, and biochemical tests (catalase, oxidase, motility, indole, and sugar fermentation) were conducted for preliminary identification. All bacterial isolates were found to be Gram-positive, consistent with characteristics of lactic acid bacteria (LAB). Based on phenotypic and biochemical profiles, the dominant isolates were identified as Lactobacillus desiosus, Lactobacillus coryneformis, Lactobacillus xylosus, and Candida crusei. The predominance of LAB indicates their potential ecological role in maintaining intestinal balance and supporting digestive processes in B. latro. These findings provide foundational insight into the composition of the gut microbiota of coconut crabs and emphasize the ecological importance of LAB–yeast associations in their gastrointestinal ecosystem.

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