Characterization and Lipolytic Activity of Staphylococcus Strains Isolated from Thai Fermented Fish Products

• Main Author: Yiamsombut S.
• Other Authors: Mahidol University
• Format: Note
• Published: 2023
• Subjects: Agricultural and Biological Sciences
• Online Access: https://repository.li.mahidol.ac.th/handle/123456789/83239

Twelve tetracocci isolated from Thai fermented fish products (pla-ra, kung-chom and nam-pla) were screened for their lipolytic activity on agar plates. Most of them exhibited lipolytic activity on the medium supplemented with 1% (v/v) of tributyrin, Tween 20, Tween 40, Tween 60 or Tween 80. The isolates exhibited lipolytic activity ranging from 0.042±0.032 to 9.548±0.969 Units.mL-1 and from 0.111±0.023 to 5.939±0.119 Units.mL-1 when cultivated in broth supplemented with 1% (v/v) Tween 20 and Tween 80, respectively. In the media containing 1% (v/v) coconut oil, lard or palm oil, the lypolytic activity was 0.042±0.032 to 9.548±0.969 Units.mL-1, 0.548±0.009 to 6.00±0.136 Units.mL-1 and 0.83 ±0.020 to 5.25±0.030 Units.mL-1, respectively, when incubated at 37 ℃ for 24 h. The isolates were identified as members of the genus Staphylococcus based on their phenotypic characteristics and 16S rRNA gene sequences. They were closely related to S. nepalensis NCTC 13834T, S. condimenti DSM 11674T, S. simulans ATCC 27848T, S. hominis subsp. novobiosepticus GTC 1228T, S. edaphicus P5085T, S. saprophyticus subsp. saprophyticus ATCC 15305T and S. lloydii ATCC 43959T, with 99.78-100 % similarity. Isolate SPJ-1 from kung-chom, identified as S. condimenti, exhibited the highest lipolytic activity (6.287±0.159, 5.939±0.119 and 5.996±0.136 Units.mL-1) when cultivated in Tween 20, Tween 80 and lard.