Dwidar, Mohammed Kim, Seil Jeon, Byoung Seung Um, Youngsoon Mitchell, Robert J. Sang, Byoung-In 2024-01-20T13:01:06Z 2024-01-20T13:01:06Z 2021-09-01 2013-03 https://pubs.kist.re.kr/handle/201004/128327 Background: Currently, the most promising microorganism used for the bio-production of butyric acid is Clostridium tyrobutyricum ATCC 25755(T); however, it is unable to use sucrose as a sole carbon source. Consequently, a newly isolated strain, Bacillus sp. SGP1, that was found to produce a levansucrase enzyme, which hydrolyzes sucrose into fructose and glucose, was used in a co-culture with this strain, permitting C. tyrobutyricum ATCC 25755(T) to ferment sucrose to butyric acid. Results: B. sp. SGP1 alone did not show any butyric acid production and the main metabolite produced was lactic acid. This allowed C. tyrobutyricum ATCC 25755(T) to utilize the monosaccharides resulting from the activity of levansucrase together with the lactic acid produced by B. sp. SGP1 to generate butyric acid, which was the main fermentative product within the co-culture. Furthermore, the final acetic acid concentration in the co-culture was significantly lower when compared with pure C. tyrobutyricum ATCC 25755(T) cultures grown on glucose. In fed-batch fermentations, the optimum conditions for the production of butyric acid were around pH 5.50 and a temperature of 37 degrees C. Under these conditions, the final butyrate concentration was 34.2 +/- 1.8 g/L with yields of 0.35 +/- 0.03 g (butyrate)/g (sucrose) and maximum productivity of 0.3 +/- 0.04 g/L/h. Conclusions: Using this co-culture, sucrose can be utilized as a carbon source for butyric acid production at a relatively high yield. In addition, this co-culture offers also the benefit of a greater selectivity, with butyric acid constituting 92.8% of the acids when the fermentation was terminated. English BioMed Central Co-culturing a novel Bacillus strain with Clostridium tyrobutyricum ATCC 25755 to produce butyric acid from sucrose Article 10.1186/1754-6834-6-35 1 Biotechnology for Biofuels, v.6 Biotechnology for Biofuels 6 Y scie scopus 000316668300001 2-s2.0-84874447163 Biotechnology & Applied Microbiology Energy & Fuels Biotechnology & Applied Microbiology Energy & Fuels Article FERMENTATION LEVANSUCRASE GLUCOSE DEXTRANSUCRASE EZTAXON XYLOSE STAIN Butyric acid Sucrose Levansucrase Co-culture Clostridium tyrobutyricum ATCC 25755 Bacillus sp SGP1