Integration of food raw materials, food microbiology, and food additives: systematic research and comprehensive insights into sweet sorghum juice, Clostridium tyrobutyricum TGL-A236 and bio-butyric acid

• Published in: Frontiers in microbiology Vol. 15; p. 1410968
• Main Authors: Liu, Mei-Han, Zhou, Xiang, Zhang, Miao-Miao, Wang, Ya-Juan, Zhou, Bo, Ding, Nan, Wu, Qing-Feng, Lei, Cai-Rong, Dong, Zi-Yi, Ren, Jun-Le, Zhao, Jing-Ru, Jia, Cheng-Lin, Liu, Jun, Lu, Dong, Zhong, Hai-Yan
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Media S.A 30.05.2024
• Subjects: bio-butyric acid; Clostridium tyrobutyricum TGL-A236; Microbiology; pathway and process enrichment; protein homology modeling; qRT-PCR; sweet sorghum juice; sweet sorghum juice; pathway and process enrichment; qRT-PCR; protein cavity; Clostridium tyrobutyricum TGL-A236; bio-butyric acid; protein homology modeling
• ISSN: 1664-302X; 1664-302X
• DOI: 10.3389/fmicb.2024.1410968

Sweet sorghum juice is a typical production feedstock for natural, eco-friendly sweeteners and beverages. is one of the widely used microorganisms in the food industry, and its principal product, bio-butyric acid is an important food additive. There are no published reports of producing butyric acid using SSJ as the sole substrate without adding exogenous substances, which could reach a food-additive grade. This study focuses on tailoring a cost-effective, safe, and sustainable process and strategy for their production and application. This study modeled the enzymolysis of non-reducing sugars via the first/second-order kinetics and added food-grade diatomite to the hydrolysate. Qualitative and quantitative analysis were performed using high-performance liquid chromatography, gas chromatography-mass spectrometer, full-scale laser diffraction method, ultra-performance liquid chromatography-tandem mass spectrometry, the cell double-staining assay, transmission electron microscopy, and Oxford nanopore technology sequencing. Quantitative real-time polymerase chain reaction, pathway and process enrichment analysis, and homology modeling were conducted for mutant genes. The treated sweet sorghum juice showed promising results, containing 70.60 g/L glucose and 63.09 g/L fructose, with a sucrose hydrolysis rate of 98.29% and a minimal sucrose loss rate of 0.87%. Furthermore, 99.62% of the colloidal particles and 82.13% of the starch particles were removed, and the concentrations of hazardous substances were effectively reduced. A food microorganism TGL-A236 with deep utilization value was developed, which showed superior performance by converting 30.65% glucose and 37.22% fructose to 24.1364 g/L bio-butyric acid in a treated sweet sorghum juice (1:1 dilution) fermentation broth. This titer was 2.12 times higher than that of the original strain, with a butyric acid selectivity of 86.36%. Finally, the Genome atlas view, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and evolutionary genealogy of genes: Non-supervised Orthologous (eggNOG) functional annotations, three-dimensional structure and protein cavity prediction of five non-synonymous variant genes were obtained. This study not only includes a systematic process flow and in-depth elucidation of relevant mechanisms but also provides a new strategy for green processing of food raw materials, improving food microbial performance, and ensuring the safe production of food additives.