食品科学 ›› 2018, Vol. 39 ›› Issue (24): 108-115.doi: 10.7506/spkx1002-6630-201824017

• 生物工程 • 上一篇    下一篇

1 株类胡萝卜素产生菌的鉴定及其发酵培养基的优化

孔维宝,杨?洋,陈?冬,汪?洋,达文燕,牛世全   

  1. (西北师范大学生命科学学院,甘肃?兰州 730070)
  • 出版日期:2018-12-25 发布日期:2018-12-17
  • 基金资助:
    国家自然科学基金地区科学基金项目(31360192)

Identification of a Carotenoid-Producing Strain and Optimization of Fermentation Medium

KONG Weibao, YANG Yang, CHEN Dong, WANG Yang, DA Wenyan, NIU Shiquan   

  1. (College of Life Sciences, Northwest Normal University, Lanzhou 730070, China)
  • Online:2018-12-25 Published:2018-12-17

摘要: 利用形态学、生理生化和rDNA-ITS序列分析相结合的方法鉴定1 株产类胡萝卜素的菌株K-1,采用比色法测定其生长和所产类胡萝卜素的稳定性,借助单因素试验和正交试验优化K-1菌株的发酵条件。结果表明,菌株K-1为胶红酵母(Rhodotorula mucilaginosa),最适生长温度30?℃,生长pH值范围2~7;含有红酵母烯,所产色素的基本稳定性良好,但高温(>60?℃)、强光和添加氧化剂H2O2可使其稳定性下降。菌株K-1产类胡萝卜素的最适发酵条件为20?g/L葡萄糖、20?g/L?(NH4)2SO4、2?g/L无水CaCl2、5?g/L柠檬酸三钠(培养温度30?℃、接种量10%、摇床转速150?r/min、装瓶量50?mL/250?mL、初始pH?5.5、培养5?d);优化条件下类胡萝卜素产量达(180.14±2.45)μg/g(干菌体)。研究表明,菌株K-1具有高产类胡萝卜素的潜能,色素稳定性良好,可为微生物类胡萝卜素的发酵生产提供菌种资源。

关键词: 类胡萝卜素, 胶红酵母, 鉴定, 色素稳定性, 发酵条件

Abstract: A strain K-1 with carotenoid-producing potential was identified using morphological, physiological, biochemical tests and rDNA-ITS sequence analysis. A colorimetric method was used to determine mycelial growth and the stability of carotenoids produced by this strain. The fermentation conditions of strain K-1 were optimized by one-factor-at-a-time and orthogonal array design methods. The results indicated that K-1 was identified as Rhodotorula mucilaginosa. The optimum temperature for growth of the strain was 30 ℃, and it could be grown well in the initial pH range from 2 to 7. The characteristic absorption peak indicated that the acetone extract of cultured cells of K-1 contained torulene. The carotenoids produced by K-1 had good stability, but the stability was decreased under the conditions of high temperature (> 60 ℃), intense light and oxidant H2O2. The optimum fermentation conditions were determined as follows: glucose 20 g/L, (NH4)2SO4 20 g/L, anhydrous CaCl2 2 g/L, trisodium citrate 5 g/L, temperature 30 ℃, inoculum size 10%, shaking speed 150 r/min, medium volume 50 mL/250 mL, initial pH 5.5, and time 5 d. The yield of carotenoids on a dry mycelial mass basis was (180.14 ± 2.45) μg/g under the optimum culture conditions. Strain K-1 has the potential to produce a high yield of carotenoids, and the pigment produced by it has good stability. This strain represents a new microbial resource for carotenoids production.

Key words: carotenoids, Rhodotorula mucilaginosa, identification, pigment stability, fermentation process

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