<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Caproic acid is the precursor material of ethyl hexanoate, a representative flavor substance in strong flavor baijiu (SFB). Increasing the content of caproic acid in SFB helps to improve its quality. In the present study, caproic acid-producing bacteria from the pit mud of an SFB ecosystem were isolated, purified, and characterized. Strain BF-1 with the highest caproic acid yield (0.88 g/l) was selected. The morphological and molecular identification analysis showed that strain BF-1 was <italic>Enterococcus casseliflavus</italic>. The genome of <italic>E. casseliflavus</italic> BF-1 was sequenced and was found to be 2,968,377 bp in length with 3,270 open reading frames (ORFs). The caproic acid biosynthesis pathway in <italic>E. casseliflavus</italic> BF-1 was predicted based on the KAAS annotation. The virulence factors in the genome of strain BF-1 were annotated, which showed that <italic>E. casseliflavus</italic> BF-1 is safe at the genetic level. After adding essential nutrients based on the KAAS annotation, the optimum medium conditions for acid production by strain BF-1 were obtained by performing orthogonal experiments. The caproic acid yield of strain BF-1 reached 3.03 g/l, which was 3.44-fold higher than the initial yield. The optimized fer-</p>
<p>mentation of caproic acid production by BF-1 was reported for the first time. The strain could be further used to regulate the ecosystem in baijiu production to improve its quality.</p></abstract>

Caproic acid is the precursor material of ethyl hexanoate, a representative flavor substance in strong flavor baijiu (SFB). Increasing the content of caproic acid in SFB helps to improve its quality. In the present study, caproic acid-producing bacteria from the pit mud of an SFB ecosystem were isolated, purified, and characterized. Strain BF-1 with the highest caproic acid yield (0.88 g/l) was selected. The morphological and molecular identification analysis showed that strain BF-1 was Enterococcus casseliflavus. The genome of E. casseliflavus BF-1 was sequenced and was found to be 2,968,377 bp in length with 3,270 open reading frames (ORFs). The caproic acid biosynthesis pathway in E. casseliflavus BF-1 was predicted based on the KAAS annotation. The virulence factors in the genome of strain BF-1 were annotated, which showed that E. casseliflavus BF-1 is safe at the genetic level. After adding essential nutrients based on the KAAS annotation, the optimum medium conditions for acid production by strain BF-1 were obtained by performing orthogonal experiments. The caproic acid yield of strain BF-1 reached 3.03 g/l, which was 3.44-fold higher than the initial yield. The optimized fer-
mentation of caproic acid production by BF-1 was reported for the first time. The strain could be further used to regulate the ecosystem in baijiu production to improve its quality.

Isolation, Identification, and Fermentation Medium Optimization of a Caproic Acid‑Producing <italic>Enterococcus casseliflavus</italic> Strain from Pit Mud of Chinese Strong Flavor Baijiu Ecosystem

Polish Journal of Microbiology

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Isolation, Identification, and Fermentation Medium Optimization of a Caproic Acid‑Producing  Strain from Pit Mud of Chinese Strong Flavor Baijiu Ecosystem

Caproic acid is the precursor material of ethyl hexanoate, a representative flavor substance in strong flavor baijiu (SFB). Increasing the content of caproic...

Isolation, Identification, and Fermentation Medium Optimization of a Caproic Acid‑Producing Enterococcus casseliflavus Strain from Pit Mud of Chinese Strong Flavor Baijiu Ecosystem

Article Category: Original Paper

Published Online: Dec 21, 2022

Page range: 563 - 575

Received: Sep 19, 2022

Accepted: Nov 11, 2022

DOI: https://doi.org/10.33073/pjm-2022-052

Keywords
baijiu, caproic acid, genome sequencing, fermentation optimization

© 2022 Hao Luo et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Isolation, Identification, and Fermentation Medium Optimization of a Caproic Acid‑Producing Enterococcus casseliflavus Strain from Pit Mud of Chinese Strong Flavor Baijiu Ecosystem

Article Category: Original Paper

Published Online: Dec 21, 2022

Page range: 563 - 575

Received: Sep 19, 2022

Accepted: Nov 11, 2022

DOI: https://doi.org/10.33073/pjm-2022-052

Keywordsbaijiu, caproic acid, genome sequencing, fermentation optimization

© 2022 Hao Luo et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Keywords
baijiu, caproic acid, genome sequencing, fermentation optimization