Gamma-aminobutyric acid(GABA)is a natural non-protein functio nal amino acid,which has potential for fermentation industrial production by Lactobacillus brevis.This work investigated the batch fermentation process and...Gamma-aminobutyric acid(GABA)is a natural non-protein functio nal amino acid,which has potential for fermentation industrial production by Lactobacillus brevis.This work investigated the batch fermentation process and developed a kinetic model based on substrate restrictive model established by experimental data from L25(5~6)orthogonal experiments.In this study,the OD600 value of fermentation broth was fixed to constant after reaching its maximum because the microorganism death showed no effect on the enzyme activity of glutamate decarboxylase(GAD).As pH is one of the key parameters in fermentation process,a pH-dependent kinetic model based on radial basis function was developed to enhance the practicality of the model.Furthermore,as to decrease the deviations between the simulated curves and the experimental data,the rolling correction strategy with OD600 values that was measured in real-time was introduced into this work to modify the model.Finally,the accu racy of the rolling corrected and pH-dependent model was validated by good fitness between the simulated curves and data of the initial batch fermentation(pH 5.2).As a result,this pH-dependent kinetic model revealed that the optimal pH for biomass growth is 5.6-5.7 and for GABA production is about 5,respectively.Therefore,the developed model is practical and convenient for the instruction of GABA fermentation production,and it has instructive significance for the industrial scale.展开更多
γ-Aminobutyric acid(GABA),a natural non-protein amino acid,plays an irreplaceable role in regulating the life activities of organisms.Nowadays,the separation and purification of food-grade GABA from fermentation brot...γ-Aminobutyric acid(GABA),a natural non-protein amino acid,plays an irreplaceable role in regulating the life activities of organisms.Nowadays,the separation and purification of food-grade GABA from fermentation broth is still a great challenge.This research utilized monosodium glutamate as a substrate for the production of high-purity GABA via an integrated process incorporating fermentation,purification,and crystallization.Firstly,147 g·L^(-1) GABA with a yield of 99.8%was achieved through fed-batch fermentation by Lactobacillus brevis CE701.Secondly,three integrated purification methods by ethanol precipitation were compared,and crude GABA with a purity of 89,85%was obtained by the optimized method.Thirdly,GABA crystals with a purity of 98.69%and a yield of 60%were further obtained through a designed crystallization process.Furthermore,the GABA industrial production process model was established by Superproper Designer V10 software,and material balance and economic analysis were carried out.Ethanol used in the process was recovered with a recovery of 98.79%through Aspen simulated extractive distillation.Then the fixed investment(equipment purchase and installation costs)for an annual production of 80 t GABA will be about 833000 USD;the total annual production cost(raw material cost and utility cost)will be about 641000 USD.The annual sale of GABA may be at the range of 2400000-4000000 USD and the payback period will be about 1-2 year.This integrated process provides a potential way for the industrial-scale production of food-grade GABA.展开更多
Dissecting the genetic components that contribute to the two main subphenotypes of steroid-sensitive nephrotic syndrome(SSNS)using genome-wide association studies(GWAS)strategy is important for understanding the disea...Dissecting the genetic components that contribute to the two main subphenotypes of steroid-sensitive nephrotic syndrome(SSNS)using genome-wide association studies(GWAS)strategy is important for understanding the disease.We conducted a multicenter cohort study(360 patients and 1835 controls)combined with a GWAS strategy to identify susceptibility var-iants associated with the following two subphenotypes of ssNS:steroid-sensitive nephrotic syn-drome without relapse(SSNswR,181 patients)and steroid-dependent/frequent relapse nephrotic syndrome(SDNS/FRNS,179 patients).The distribution of two single-nucleotide poly-morphisms(SNPs)in ANKRD36 and ALPG was significant between SSNSWR and healthy controls,and that of two SNPs in GAD1 and HLA-DQA1 was significant between SDNS/FRNS and healthy controls.Interestingly,rs1047989 in HLA-DQA1 was a candidate locus for SDNS/FRNS but not for SSNSWR.No significant SNPs were observed between SSNSWR and SDNS/FRNS.Meanwhile,chromosome 2:171713702 in GAD1 was associated with a greater steroid dose(>0.75 mg/kg/d)upon relapse to first remission in patients with SDNS/FRNS(odds ratio=3.14;95%confidence interval,0.97-9.87;P=0.034).rs117014418 in APOL4 was significantly associated with a decrease in eGFR of greater than 20%compared with the baseline in SDNS/FRNS patients(P=0.0001).Protein-protein intersection network construction suggested that HLA-DQA1 and HLA-DQB1 function together through GSDMA.Thus,SSNSWR belongs to non-HLA region-dependent nephropathy,and the HLA-DQA/DQB region is likely strongly associated with dis-ease relapse,especially in SDNS/FRNS.The study provides a novel approach for the GWAS strategy of SsNS and contributes to our understanding of the pathological mechanisms of SSNSWRandSDNS/FRNS.展开更多
基金supported by the National Natural Science Foundation of China(21621004,22078239)the Beijing-Tianjin-Hebei Basic Research Cooperation Project(B2021210008)+1 种基金Tianjin Synthetic Biotechnology Innovation Capacity Improvement Project(TSBICIP-KJGG-004)the Tianjin Development Program for Innovation and Entrepreneurship(2018)。
文摘Gamma-aminobutyric acid(GABA)is a natural non-protein functio nal amino acid,which has potential for fermentation industrial production by Lactobacillus brevis.This work investigated the batch fermentation process and developed a kinetic model based on substrate restrictive model established by experimental data from L25(5~6)orthogonal experiments.In this study,the OD600 value of fermentation broth was fixed to constant after reaching its maximum because the microorganism death showed no effect on the enzyme activity of glutamate decarboxylase(GAD).As pH is one of the key parameters in fermentation process,a pH-dependent kinetic model based on radial basis function was developed to enhance the practicality of the model.Furthermore,as to decrease the deviations between the simulated curves and the experimental data,the rolling correction strategy with OD600 values that was measured in real-time was introduced into this work to modify the model.Finally,the accu racy of the rolling corrected and pH-dependent model was validated by good fitness between the simulated curves and data of the initial batch fermentation(pH 5.2).As a result,this pH-dependent kinetic model revealed that the optimal pH for biomass growth is 5.6-5.7 and for GABA production is about 5,respectively.Therefore,the developed model is practical and convenient for the instruction of GABA fermentation production,and it has instructive significance for the industrial scale.
基金supported by the National Natural Science Foundation of China(Nos.21621004,22078239)the Beijing-Tianjin-Hebei Basic Research Cooperation Project(B2021210008)the Tianjin Development Program for Innovation and Entrepreneurship(2018)。
文摘γ-Aminobutyric acid(GABA),a natural non-protein amino acid,plays an irreplaceable role in regulating the life activities of organisms.Nowadays,the separation and purification of food-grade GABA from fermentation broth is still a great challenge.This research utilized monosodium glutamate as a substrate for the production of high-purity GABA via an integrated process incorporating fermentation,purification,and crystallization.Firstly,147 g·L^(-1) GABA with a yield of 99.8%was achieved through fed-batch fermentation by Lactobacillus brevis CE701.Secondly,three integrated purification methods by ethanol precipitation were compared,and crude GABA with a purity of 89,85%was obtained by the optimized method.Thirdly,GABA crystals with a purity of 98.69%and a yield of 60%were further obtained through a designed crystallization process.Furthermore,the GABA industrial production process model was established by Superproper Designer V10 software,and material balance and economic analysis were carried out.Ethanol used in the process was recovered with a recovery of 98.79%through Aspen simulated extractive distillation.Then the fixed investment(equipment purchase and installation costs)for an annual production of 80 t GABA will be about 833000 USD;the total annual production cost(raw material cost and utility cost)will be about 641000 USD.The annual sale of GABA may be at the range of 2400000-4000000 USD and the payback period will be about 1-2 year.This integrated process provides a potential way for the industrial-scale production of food-grade GABA.
基金funded by the China National Natural Science Foundation(No.81970618,82170720,82200788)China National Clinical Research Centre Foundation(No.NCRC-2019-GP-02)+2 种基金Science and Technology Research Project of Chongqing Education Commission of China(No.KJZDM201900401)Chongqing Science and Health Joint Medical Research Project(China)(No.2023GGXM001)National Key R&D Program of China(No.2022YFC2705101).
文摘Dissecting the genetic components that contribute to the two main subphenotypes of steroid-sensitive nephrotic syndrome(SSNS)using genome-wide association studies(GWAS)strategy is important for understanding the disease.We conducted a multicenter cohort study(360 patients and 1835 controls)combined with a GWAS strategy to identify susceptibility var-iants associated with the following two subphenotypes of ssNS:steroid-sensitive nephrotic syn-drome without relapse(SSNswR,181 patients)and steroid-dependent/frequent relapse nephrotic syndrome(SDNS/FRNS,179 patients).The distribution of two single-nucleotide poly-morphisms(SNPs)in ANKRD36 and ALPG was significant between SSNSWR and healthy controls,and that of two SNPs in GAD1 and HLA-DQA1 was significant between SDNS/FRNS and healthy controls.Interestingly,rs1047989 in HLA-DQA1 was a candidate locus for SDNS/FRNS but not for SSNSWR.No significant SNPs were observed between SSNSWR and SDNS/FRNS.Meanwhile,chromosome 2:171713702 in GAD1 was associated with a greater steroid dose(>0.75 mg/kg/d)upon relapse to first remission in patients with SDNS/FRNS(odds ratio=3.14;95%confidence interval,0.97-9.87;P=0.034).rs117014418 in APOL4 was significantly associated with a decrease in eGFR of greater than 20%compared with the baseline in SDNS/FRNS patients(P=0.0001).Protein-protein intersection network construction suggested that HLA-DQA1 and HLA-DQB1 function together through GSDMA.Thus,SSNSWR belongs to non-HLA region-dependent nephropathy,and the HLA-DQA/DQB region is likely strongly associated with dis-ease relapse,especially in SDNS/FRNS.The study provides a novel approach for the GWAS strategy of SsNS and contributes to our understanding of the pathological mechanisms of SSNSWRandSDNS/FRNS.
