Abstract

Kombucha is a traditional drink obtained from sugared tea that is transformed by a community of yeasts and bacteria. Its production has become industrialized, and the study of the microbial community’s evolution is needed to improve control over the process. This study followed the microbial composition of black and green kombucha tea over three consecutive years in a production facility using a culture-dependent method. Microorganisms were isolated and cultivated using selective agar media. The DNA of isolates was extracted, amplified using 26S and 16S PCR, and sequenced. Identities were obtained after a comparison to the NCBI database. Dekkera/Brettanomyces bruxellensis, Hanseniaspora valbyensis and Saccharomyces cerevisiae were the major yeast species, and the major bacterial genera were Acetobacter and Liquorilactobacillus. Results highlight the persistence of yeast species such as B. bruxellensis detected in 2019. Some yeasts species appeared to be sensitive towards stressful events, such as a hot period in 2019. However, they were resilient and isolated again in 2021, as was the case for H. valbyensis. Dominance of B. bruxellensis was clear in green and black tea kombucha, but proportions in yeasts varied depending on tea type and phase (liquid or biofilm). Composition in acetic acid and lactic acid bacteria showed a higher variability than yeasts with many changes in species over time.

Highlights

  • Kombucha is a drink obtained from sugared tea infusion through the activity of a symbiotic microbial community composed of yeasts

  • A cellulosic biofilm develops due to acetic acid bacteria and includes two environments for the development of microorganisms, which include a liquid phase, where the microorganisms have a planktonic lifestyle, and a solid phase, a cellulosic biofilm called kombucha pellicle or SCOBY (Symbiotic Culture Of Bacteria and Yeasts) produced by acetic acid bacteria, where sessile cells remain [7,9]

  • 2020, as in green tea, a (Figure 3): B. bruxellensis, H. valbyensis, C. californica and S. cerevisiae, which have already massive drop in diversity was observed to the point that only bruxellensis was detected been identified in kombucha [2]

Read more

Summary

Introduction

Kombucha is a drink obtained from sugared tea infusion through the activity of a symbiotic microbial community composed of yeasts (including Saccharomyces cerevisiae, Torulaspora delbrueckii, Dekkera/Brettanomyces bruxellensis (abridged B. bruxellensis) and bacteria, including acetic (mainly Komagataeibacter, Gluconobacter and Acetobacter genera) and sometimes lactic acid bacteria (from the genera Lactobacillus and Liquorilactobacillus) [1,2,3]. Kombucha is a combination of several microbial activities, including alcoholic fermentation by yeasts and the oxidative metabolism by acetic bacteria [5]. The sucrose added to the tea is hydrolyzed into glucose and fructose by the invertase activity of yeasts, which produce ethanol through alcoholic fermentation. A cellulosic biofilm develops due to acetic acid bacteria and includes two environments for the development of microorganisms, which include a liquid phase, where the microorganisms have a planktonic lifestyle, and a solid phase, a cellulosic biofilm called kombucha pellicle or SCOBY (Symbiotic Culture Of Bacteria and Yeasts) produced by acetic acid bacteria, where sessile cells remain [7,9]

Methods
Results
Discussion
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.