摘要
考查了表面活性物质Triton X-100对Streptococcus equisimilis FE-11发酵透明质酸产量和分子量的影响。结果发现:向S.equisimilis FE-11培养体系中添加Triton X-100对透明质酸产量和分子量的影响效果与添加时机和剂量紧密相关,在发酵的第6小时添加Triton X-100至5 g/L可以使透明质酸产量和分子量同时达到最高水平。5 L发酵罐验证实验表明,应用该添加策略可使透明质酸产量和分子量分别提高至4.21 g/L和2.49 MDa。与不添加Triton X-100相比,分别提升了15.34%和29.02%。与此同时,S.equisimilis FE-11细胞膜结构中饱和脂肪酸/不饱和脂肪酸的比率从0.80降低至0.50,添加Triton X-100显著改变了菌体细胞膜结构,改善了细胞膜的流动性和通透性,促进了透明质酸产量和分子量的提升。
The effects of Triton X-100 on hyaluronic acid production and molecular weight in Streptococcus equisimilis FE-11 fermentation were investigated. The results showed that the effect of adding Triton X-100 system on hyaluronic acid production and molecular weight was closely related to the timing and dosage of adding Triton X-100 during S. equisimilis FE-11 cultivation. Adding Triton X-100 to 5 g/L at the 6 th hour of fermentation could make hyaluronic acid production and molecular weight reach the highest level at the same time. Validation experiments in 5 L fermentor showed that the production and molecular weight of hyaluronic acid were increased to 4.21 g/L and 2.49 MDa respectively by using this addition strategy,which increased by 15.34% and 29.02% respectively compared with that without Triton X-100 addition. Meanwhile, the ratio of saturated fatty acid to unsaturated fatty acid in cell membrane of S.equisimilis FE-11 decreased from 0.80 to 0.50. The addition of Triton X-100 significantly changed the structure of cell membrane, improved the fluidity and permeability of cell membrane, and promoted the production and molecular weight of hyaluronic acid.
引文
[1]张照明,冯强.高玲玲.透明质酸的产需情况及市场分析[J].精细与专用化学品,2007(9):24-27.
[2]郜娇娇,杨树林.基因工程技术优化透明质酸生产的研究进展[J].中国生物工程杂志,2017,37(8):72-77.
[3] Shah MV, Badle SS, Ramachandran KB. Hyaluronic acid production and molecular weight improvement by redirection of carbon flux towards its biosynthesis pathway[J].Biochem Eng J,2013, 80:53-60.
[4] Armstrong DC, Johns MR. Culture conditions affect the molecular weight properties of hyaluronic acid produced by streptococcus zooepidemicus[J].Appl Environ Microbiol,1997, 63:2759-2764.
[5] Jagannath S, Ramachandran KB. Influence of competing metabolic processes on the molecular weight of hyaluronic acid sunthesized by Streptococcus zooepidemicus[J]. Biochem Eng J, 2010,48(2):148-158.
[6] Pires AM, Santana MH. Metabolic effects of the initial glucose concentration on microbial production of hyaluronic acid[J].Appl Biochem Biotechnol, 2010, 162(6):1751-1761.
[7]吕哲喆,刘晓侠,孙诗清.表面活性剂对天然红色素发酵的影响[J].药物生物技术, 2012(4):324-327.
[8]贺玉广,周思,胡晓云,等.表面活性剂对加利链霉菌AF1发酵的影响[J].华南农业大学学报, 2017, 38(6):72-78.
[9] Hubbard C, Mc Namara JT, Azumaya C, et al. The hyaluronan synthase catalyzes the synthesis and membrane translocation of hyaluronan[J]. J Mol Biol,2012, 418:21-31.
[10] Sun J, Wang M, Chen Y. Understanding the influence of phosphatidylcholine on the molecular weight of hyaluronic acid synthesized by Streptococcus zooepidemicus[J]. Appl Biochem Biotechnol, 2012,168(1):47-57.
[11] BitterT. Ewins R. Modified carbazole reaction for uronic acid[J].Biol Chem,1961,81:43.
[12] LaurentTC, M Ryan, A Pietruszkiewicz. Fraction of hyaluronic acid. The polydispersity of hyaluronic acid from the bovine vitreous body[J]. Biochim Biophys Acta,1960,42:476-485.
[13] Nemec T, Jeernejc K. Influence of Tween 80 on lipid metabolism of an aspergillus niger strain. Appl[J]. Biochem. Biotechnol, 2002,101:229-238.