Kombucha Tea as a Reservoir of Cellulose Producing Bacteria: Assessing Diversity Among Komagataeibacter Isolates

Abstract

Bacterial cellulose (BC) is receiving great attention due to its unique properties such as high purity, water retention capacity, high mechanical strength, and biocompatibility. However, the production of BC has been limited because of high cost and low productivity. In this light, the isolation of new BC producing bacteria and selection of high productive strains became a promising issue. Kombucha tea is a fermented beverage in which the bacteria fraction of the microbial community is composed mostly by strains belonging to the genus Komagataeibacter. In this study Kombucha tea production trials were performed starting from a previous batch, and bacterial isolation was conducted along cultivation time. From the whole microbial pool, 46 isolates were tested for their ability in producing BC. The obtained BC yield ranged from 0.59 g/L, for the isolate K2G36, to 23 g/L for K2G30 used as the reference strain. The genetic intraspecific diversity of the 46 isolates was investigated using two repetitive-sequence-based PCR typing methods, which are the enterobacterial repetitive intergenic consensus (ERIC) elements and the (GTG)5 sequences, respectively. The results obtained using two different approaches revealed the suitability of the fingerprints techniques, showing a discrimination power, calculated as D index, of 0.94 for (GTG)5 rep-PCR and 0.95 for ERIC rep-PCR. In order to improve the sensitivity of the applied method, a combined model from the two genotyping experiments was performed, allowing to discriminate among strains.

Assessing effectiveness of Komagataeibacter strains for producing surface-microstructured cellulose via guided assembly-based biolithography

“…Due to high intraspecific variability within AAB in producing BC 26 , 9 strains were selected based on BC production yield and shape. Selected strains were cultured inside the bioreactor and their characteristics of the symmetrical array on the surface were analysed.…”

A novel repeat sequence-based PCR (rep-PCR) using specific repeat sequences of Mycobacterium intracellulare as a DNA fingerprinting

“…Set of primers were used in the PCR experiments, single primer (BOX A1R or CCG 4 ), in pairs (ERIC 1R + ERIC 2), or in combination (BOX A1R + ERIC 1R + ERIC 2, BOX A1R + REP 1RI + REP2I, and BOX A1R + ERIC 1R + ERIC 2 + REP 1RI + REP 2I) (Table 1). Previous published rep-PCR reaction was conducted as follows: initial denaturation at 95°C for 5 min; 30 cycles of 95°C for 30 s, 40°C for 1 min, and 72°C for 2 min; and a final extension at 72°C for 7 min (Chen et al, 2021;Jena et al, 2021;La China et al, 2021;Teixeira et al, 2021).…”

Disposable Food Packaging and Serving Materials—Trends and Biodegradability

“…Bacterial cellulose (BC) is an extracellular polymer of bacteria belonging to Achromobacter, Alcaligenes, Aerobacter, Agrobacterium, Azotobacter, Komagataeibacter (formerly Gluconacetobacter ), Pseudomonas, Rhizobium, Sarcina, Dickeya, and Rhodobacter genera [ 83 , 84 ]. However, the strains belonging to the genus Komagataeibacter are most commonly used in research and the commercial production of bacterial cellulose [ 85 , 86 ]; Komagataeibacter xylinus is considered a microbial model in BC production [ 87 , 88 ]. The primary structure of the bacterial cellulose consists of long-chain β-1,4-linked glucose (glucan chains), reaching a degree of polymerization up to 20,000 [ 89 ].…”