In Maotai-flavor Baijiu production,reducing lactic acid(LA)can alleviate microbial imbalance and flavor disharmony caused by LA accumulation.Current methods for reducing LA mainly focus on physical removal and ferment...In Maotai-flavor Baijiu production,reducing lactic acid(LA)can alleviate microbial imbalance and flavor disharmony caused by LA accumulation.Current methods for reducing LA mainly focus on physical removal and fermentation parameter control,but they address only the symptoms,not the underlying cause.This study selected Lactobacillus panis antagonistic bacteria to control LA production at its source by inhibiting L.panis growth and analyzed its antimicrobial substances and mechanisms.Firstly,a high-throughput screening method for L.panis antagonists was developed based on lactate dehydro-genase,which correlates LA concentration with reduced nicotinamide adenine dinucleotide(NADH).Subsequently,a total of 34 antagonists were screened,with Bacillus licheniformis BL-4 exhibiting the highest inhibition rate(62.25%)against L.panis.Moreover,the primary antimicrobial substance,antimicrobial peptide antiL24,was purified from B.licheniformis BL-4 and evaluated for its activity and sequence.Finally,the mechanism of antiL24 against L.panis was analyzed by using microstructural analyses and transcriptomic profiling,revealing that antiL24 disrupts the cell wall and membrane of L.panis and affects genes involved in energy metabolism and protein synthesis.This study proposes a novel strategy for regulating LA concentration in Maotai-flavor Baijiu production,with the potential to enhance its quality.展开更多
基金supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(32021005)the Jiangsu Basic Research Center for Synthetic Biology(BK20233003)+1 种基金the Natural Science Foundation of Jiangsu Province(BK20202002)the Fundamental Research Funds for the Central Universities(JUSRP124034).
文摘In Maotai-flavor Baijiu production,reducing lactic acid(LA)can alleviate microbial imbalance and flavor disharmony caused by LA accumulation.Current methods for reducing LA mainly focus on physical removal and fermentation parameter control,but they address only the symptoms,not the underlying cause.This study selected Lactobacillus panis antagonistic bacteria to control LA production at its source by inhibiting L.panis growth and analyzed its antimicrobial substances and mechanisms.Firstly,a high-throughput screening method for L.panis antagonists was developed based on lactate dehydro-genase,which correlates LA concentration with reduced nicotinamide adenine dinucleotide(NADH).Subsequently,a total of 34 antagonists were screened,with Bacillus licheniformis BL-4 exhibiting the highest inhibition rate(62.25%)against L.panis.Moreover,the primary antimicrobial substance,antimicrobial peptide antiL24,was purified from B.licheniformis BL-4 and evaluated for its activity and sequence.Finally,the mechanism of antiL24 against L.panis was analyzed by using microstructural analyses and transcriptomic profiling,revealing that antiL24 disrupts the cell wall and membrane of L.panis and affects genes involved in energy metabolism and protein synthesis.This study proposes a novel strategy for regulating LA concentration in Maotai-flavor Baijiu production,with the potential to enhance its quality.