1株源于苹果汁的嗜酸耐热菌的生长代谢动力学研究

Study on the growth and metabolic kinetics of a local Alicyclobacillus acidoterrestris isolated from apple juice

【目的】建立源于苹果汁的嗜酸耐热菌的生物量、葡萄糖消耗量和产物代谢动力学模型。【方法】以苹果汁中分离得到的1株嗜酸耐热菌和标准嗜酸耐热菌为试验菌株,采用优化的AAM培养基,对两者细胞生长、基质消耗及产物代谢动力学进行研究。【结果】①以Logistic方程建立了嗜酸耐热菌在优化AAM培养基中的生长动力学模型,标准菌和分离菌生物量模型的R2分别为0.969 4和0.991 5;②顶空固相微萃取愈创木酚的条件为:DVB/CAR/PDMS萃取头,添加1.8 g Na2SO4在55℃萃取30 min;③Luedeking-Piret方程可较好地反映嗜酸耐热菌在优化AAM培养基中的基质消耗和产物生成动力学模型,其中标准菌和分离菌葡萄糖消耗量模型的R2分别为0.995 8和0.941 2,愈创木酚生成量模型的R2分别为0.991 4和0.956 5。【结论】建立了源于苹果汁的分离嗜酸耐热菌与标准嗜酸耐热菌株菌体生长、基质消耗和产物形成的数学模型;与标准嗜酸耐热菌相比,分离得到的嗜酸耐热菌的对数期相对较短,产愈创木酚能力相对较弱。

[Objective] The study is to get the biomass model,glucose consumption model and metabolite yield model. [Method] A local Alicyclobacillus acidoterrestris isolated from the Hengxing Fruit Juice Processing Company was used for the kinetics analysis, and the standard Alicyclobacillus acidoterrestris from DSMZ as the comparison. The optimized AAM was used to study the substrate consumption mecha- nism and metabolite yield mechanism. [Result] （1）Logistic equation described the biomass model very well,the R2 were 0. 969 4 for the standard strains and 0. 991 5 for the isolated strains; （2）The optimized condition for HS-SPME to detect guaiacol were：DVB/CAR/PDMS fibre, 1.8 g Na2SO4 at 55℃ for 30 min extraction. （3）Constructed Luedeking-Piret model of substrate material and metabolite,R2 were 0. 995 8 for standard strais and 0. 941 2 for isolated strain of glucose consumption model,0. 991 4 for standard strains and 0. 956 5 for isolated strain of guaiacol model. [Conclusion] The standard strain and the isolated strains were similar in 16 S rDNA sequence, but the differences existed： shorter exponential growth phase, lower guaiacol yield for the isolated strains.