氮源对德氏乳杆菌保加利亚亚种B61-3耐冻干能力的影响

汤静月; 葛绍阳; 桑跃; 赵亮; 刘贵巧

doi:10.13386/j.issn1002-0306.2022070343

氮源对德氏乳杆菌保加利亚亚种B61-3耐冻干能力的影响

doi: 10.13386/j.issn1002-0306.2022070343

汤静月^{1, 2,},
葛绍阳²,
桑跃^{2, 3},
赵亮^{2, 4, ,},
刘贵巧^1, ,

1.
河北工程大学生命科学与食品工程学院，河北邯郸 056038
2.
中国农业大学益生菌研究中心，河北三河 065200
3.
甘肃农业大学食品科学与工程学院，甘肃兰州 730070
4.
功能乳品教育部重点实验室，中国农业大学食品科学与营养工程学院，北京 100083

基金项目: 国家自然科学基金（32072196）。

详细信息

作者简介:
汤静月（1998−），女，硕士研究生，研究方向：食品微生物，E-mail：tangjybk@163.com

通讯作者:
赵亮（1983−），男，博士，副教授，研究方向：食品微生物，E-mail：lzhao@cau.edu.cn

刘贵巧（1969−），女，硕士，教授，研究方向：食品微生物，E-mail：Keli1966@sina.com

中图分类号: TS201.3
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- 文章访问数: 70
- HTML全文浏览量: 22
- PDF下载量: 11
- 被引次数: 0
出版历程
- 收稿日期: 2022-08-02
- 网络出版日期: 2023-04-18
- 刊出日期: 2023-06-01

Effect of Nitrogen Source on Freeze-dried Resistance of Lactobacillus delbrueckii subsp. bulgaricus B61-3

TANG Jingyue^{1, 2
,},
GE Shaoyang²,
SANG Yue^{2, 3},
ZHAO Liang^{2, 4
, ,},
LIU Guiqiao^{1
, ,}

1.
College of Life Science and Food Engineering, Hebei University of Engineering, Handan 056038, China
2.
Probiotics Research Center, China Agricultural University, Sanhe 065200, China
3.
College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China
4.
Key Laboratory of Functional Dairy, Ministry of Education, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China

摘要

摘要: 本研究针对德氏乳杆菌保加利亚亚种B61-3，分别测定了其对16种氮源的利用情况，筛选出能够提高菌株冻干耐受的氮源种类及添加量，并进一步测定该氮源对菌株冻干粉发酵活力、菌体形态、发酵关键酶活力的影响。结果表明：氮源为30 g/L牛骨蛋白胨时可提高菌株冻干存活率及冻干粉发酵活力，冻干存活率由9.68%提高到18.90%，冻干粉平均发酵活力较对照组提高22.15%；电子显微镜显示，牛骨蛋白胨培养后菌体大小及形态有所改变，对照组发酵菌体表现出不规则、卷曲的形态且菌体较长，而牛骨蛋白胨为氮源时菌体形态呈表面光滑的短杆状，菌体长径比（l/d）和面积体积比（S/V）显著降低（P<0.05），可能与菌株更高的存活率和发酵活力有关。发酵关键酶活力测定结果表明，冷冻干燥显著降低菌株酶活力（P<0.05），牛骨蛋白胨培养菌株冻干后胞内酶活力均显著高于对照组（P<0.05），乳酸脱氢酶、Na^＋K^＋-ATP酶及β-半乳糖苷酶分别较对照组提高1.30、1.52及2.75倍，且胞外β-半乳糖苷酶活性低于对照组。结果证实，牛骨蛋白胨培养B61-3菌体能够抵抗冷冻干燥过程对菌体细胞膜造成的损伤，减少酶外泄，从而提高冻干存活率和发酵活力。
- 德氏乳杆菌保加利亚亚种 /
- 氮源 /
- 冷冻干燥 /
- 发酵活力 /
- 菌体形态
Abstract: In this study, the utilization of 16 nitrogen sources of Lactobacillus delbrueckii subsp. bulgaricus B61-3 were determined, and the types and amounts of nitrogen sources that can improve the freeze-drying tolerance of the strain were screened out. More importantly, the effects of nitrogen source modification on the fermentation performance, cell morphology and enzyme activities of freeze-dried powder of the strain were investigated. The results showed that 30 g/L of bovine bone peptone improved the freeze-drying survival rate from 9.68% to 18.90%, and increased fermentation activity by 22.15% compared with the control group. Changed cell size and morphology of the cultured cells of bovine bone peptone were also observed by electron microscope. Cell cultured in bovine bone peptone medium represented a short rod with smooth surface, and the ratio of length to diameter or area to volume decreased significantly (P<0.05). However, cells in the control group showed irregular, curly shape and longer cells. Freeze-drying significantly reduced the enzyme activity of the strain (P<0.05). Compared with control group, the intracellular activities of these enzymes in the cells cultured in bovine bone peptone significantly increased after freeze-drying (P<0.05), and the activities of lactate dehydrogenase, β-galactosidase and Na⁺K⁺-ATPase increased by 1.30 times, 1.52 times and 2.75 times respectively, while the extracellular activities of β-galactosidase decreased. Meanwhile, the results showed that B61-3 cells cultured with bovine bone peptone could resist the damage of cell membrane caused by freeze-drying process, reduce the leakage of enzymes, thus improving the freeze-drying survival rate and fermentation activity.
- Lactobacillus delbrueckii subsp. bulgaricus /
- nitrogen source /
- freeze-drying /
- fermentation activity /
- morphology

HTML全文

图 1 德氏乳杆菌保加利亚亚种B61-3生长曲线

Figure 1. Growth curve of Lactobacillus delbrueckii subsp. bulgaria B61-3

注：菌株生长过程中pH和OD₆₀₀值变化（a）、活菌数变化（b）。

下载: 全尺寸图片幻灯片

图 2 不同氮源对菌体增殖培养的影响

Figure 2. Effects of different nitrogen sources on bacterial value-added culture

注：不同字母之间表示具有显著性差异，P<0.05，图3、图4同。

下载: 全尺寸图片幻灯片

图 3 不同氮源对菌体冷冻存活率的影响

Figure 3. Effect of different nitrogen sources on freezing survival rate of bacteria

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图 4 不同氮源及添加量对菌体冻干存活率的影响

Figure 4. Effects of different nitrogen sources and addition amount on freeze-drying survival rate of bacteria

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图 5 氮源对菌体发酵活力的影响

Figure 5. Effect of nitrogen source on fermentation activity of bacteria

注：发酵过程中pH变化（A）、滴定酸度变化（B）和活菌数生长曲线（C）。

下载: 全尺寸图片幻灯片

图 6 扫描电镜图像

Figure 6. Scanning electron microscope image

注：对照组冻干前（a）、牛骨蛋白胨组冻干前（b）、对照组冻干后（c）、牛骨蛋白胨组冻干后（d）；图7同。

下载: 全尺寸图片幻灯片

图 7 透射电镜图像图

Figure 7. Transmission electron microscope image

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图 8 牛骨蛋白胨对乳酸脱氢酶活力的影响

Figure 8. Effect of bovine bone peptone on lactate dehydrogenase activity

注：和对照组比较，*代表具有显著性差异（P<0.05），**代表具有极显著性差异（P<0.01）；图9、图10同。

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图 9 牛骨蛋白胨对Na⁺K⁺-ATP酶活力的影响

Figure 9. Effect of bovine bone peptone on Na⁺K⁺-ATPase activity

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图 10 牛骨蛋白胨对β-半乳糖苷酶活力的影响

Figure 10. Effect of bovine bone peptone on β-galactosidase activity

注：a为胞内，b为胞外。

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表 1 牛骨蛋白胨对菌体冻干的影响

Table 1. Effect of bovine bone peptone on freeze-drying of bacteria

培养基	冻干存活率（%）	冻干菌粉活菌数（lg CFU/g）
乳糖MRS基础培养基（对照组）	9.68±0.56^b	9.65±0.41^b
牛骨蛋白胨培养基（牛骨蛋白胨组）	18.90±0.76^a	10.43±0.20^a
注：同列不同字母表示组间具有显著性差异（P<0.05），表2同。

下载: 导出CSV

表 2 对照组与牛骨蛋白胨组菌体长度、直径、长径比、面积体积比统计结果

Table 2. Statistical results of bacterial length, diameter, aspect ratio and volume between control group and bovine bone peptone group

组别	菌体长度（l, μm）	菌体直径（d, μm）	长径比（l/d）	面积体积比（S/V）
对照组冻干前	6.85±0.68^a	0.68±0.03^a	10.07±0.92^a	6.69±0.27^c
牛骨蛋白胨组冻干前	4.51±1.08^b	0.66±0.04^a	6.83±0.31^b	6.39±0.57^c
对照组冻干后	6.24±0.79^a	0.60±0.05^a	10.42±0.99^a	14.55±0.51^a
牛骨蛋白胨组冻干后	3.98±0.30^b	0.64±0.03^a	6.22±1.02^b	7.66±0.46^b

下载: 导出CSV

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