1 材料与方法
1.1 试验材料
1.1.1 试验菌株及来源
1.1.2 指示菌及细胞系
1.2 试验方法
1.2.1 生长曲线及产酸能力测定
1.2.2 抑菌能力评价
1.2.3 抗生素敏感性试验
1.2.4 溶血性试验
1.2.5 耐酸耐胆盐试验
1.2.6 人工胃肠液耐受性试验
1.2.6.1 人工胃肠液制备
1.2.6.2 人工胃肠液耐受性测定
1.2.7 表面疏水性试验
1.2.8 自聚集试验
1.2.9 共聚集试验
1.2.10 对Caco-2细胞的黏附性能试验
1.2.11 细胞毒性试验
1.2.12 羊源卷曲乳杆菌DY38抗氧化试验
1.2.12.1 菌悬液、胞内提取物及发酵上清液的制备
1.2.12.2 2,2-二苯基-1-苦酰肼(DPPH)自由基清除能力测定
1.2.12.3 羟自由基(·OH)清除能力测定
1.2.12.4 超氧阴离子自由基(O2-·)清除能力测定
1.2.12.5 还原能力测定
1.3 数据统计与分析
2 结果
2.1 羊源卷曲乳杆菌DY38的生长曲线及产酸性能
2.2 羊源卷曲乳杆菌DY38对病原菌的抑制效果
表1 羊源卷曲乳杆菌DY38对指示菌的抑制效果Table 1 Inhibitory effect of Lactobacillus crispatus DY38 from goats on indicator bacteria |
| 指示菌 Indicator bacteria | 抑菌圈直径 Inhibition zone diameter/mm | 抑菌效果 Antibacterial effect |
|---|---|---|
| 大肠杆菌ATCC25922 Escherichia coli ATCC25922 | 24.26±0.35 | +++ |
| 沙门氏菌ATCC13076 Salmonella enteritidis ATCC13076 | 21.22±0.21 | +++ |
| 金黄色葡萄球菌ATCC25923 Staphylococcus aureus ATCC25923 | 22.23±0.25 | +++ |
| 产气荚膜梭菌ATCC13124 Clostridium perfringens ATCC13124 | 33.14±0.23 | +++ |
表2 羊源卷曲乳杆菌DY38对山羊源致病菌临床分离株的抑制效果Table 2 Inhibitory effect of Lactobacillus crispatus DY38 from goats on clinical isolates of pathogenic strains in goats |
| 临床分离株 Clinical isolates | 抑菌圈直径 Inhibition zone diameter/mm | 抑菌效果 Antibacterial effect |
|---|---|---|
| 山羊产肠毒素大肠杆菌SWUN3801 Enterotoxin-producing Escherichia coli SWUN3801 of goats | 25.12±0.23 | +++ |
| 山羊肠炎沙门氏菌SWUN3802 Salmonella enteritidis SWUN3802 of goats | 28.28±0.31 | +++ |
| 山羊金黄色葡萄球SWUN3803 Staphylococcus aureus SWUN3803 of goats | 22.18±0.28 | +++ |
| 山羊A型产气荚膜梭菌SWUN3804 Clostridium perfringens type A SWUN3804 of goats | 32.15±0.22 | +++ |
| 山羊B型产气荚膜梭菌SWUN3805 Clostridium perfringens type B SWUN3805 of goats | 35.16±0.27 | +++ |
| 山羊D型产气荚膜梭菌SWUN3806 Clostridium perfringens type D SWUN3806 of goats | 34.13±0.24 | +++ |
2.3 羊源卷曲乳杆菌DY38对抗生素的敏感性
表3 羊源卷曲乳杆菌DY38对抗生素的敏感性Table 3 Antibiotic susceptibility of Lactobacillus crispatus DY38 from goats mm |
| 抗生素 Antibiotics | 抑菌圈直径Inhibition zone diameter | ||
|---|---|---|---|
| 羊源卷曲乳杆菌DY38 Lactobacillus crispatus DY38 from goats | 大肠杆菌ATCC25922 Escherichia coli ATCC25922 | 金黄色葡萄球菌ATCC25923 Staphylococcus aureus ATCC25923 | |
| 氯霉素Chloromycetin | 33.80±0.69(S) | 22.38±0.66(S) | 25.04±0.14(S) |
| 四环素Tetracycline | 32.04±0.88(S) | 28.84±0.50(S) | 31.17±0.79(S) |
| 红霉素Erythromycin | 27.96±0.68(S) | 19.47±0.84(S) | 22.53±0.92(S) |
| 头孢曲松Ceftriaxone | 29.11±0.22(S) | 23.20±0.45(S) | 20.16±0.76(S) |
| 阿莫西林Amoxicillin | 33.13±0.45(S) | 18.91±0.41(S) | 22.69±0.40(S) |
| 氨苄西林Ampicillin | 31.03±0.64(S) | 20.89±0.50(S) | 25.75±0.60(S) |
| 米诺环素Minocycline | 35.13±0.90(S) | 28.11±0.14(S) | 24.98±0.56(S) |
| 利福平Rifampicin | 21.95±0.77(S) | 20.95±0.75(S) | 20.22±0.35(S) |
S:敏感 sensitivity。 |
2.4 羊源卷曲乳杆菌DY38的溶血性
2.5 羊源卷曲乳杆菌DY38对酸、胆盐及人工胃肠液的耐受性
表4 羊源卷曲乳杆菌DY38对酸、胆盐及人工胃肠液的耐受性Table 4 Tolerance of Lactobacillus crispatus DY38 from goats to acid, bile salts and artificial gastrointestinal fluid |
| 条件 Conditions | 细菌浓度Bacterial concentration/(CFU/mL) | 存活率 Survival rate/% | |
|---|---|---|---|
| 处理0 h Treated 0 h | 处理3 h Treated 3 h | ||
| pH 2.0 | (1.61±0.44)×108 | (1.01±0.15)×108 | 62.73±0.86 |
| pH 3.0 | (1.64±0.58)×108 | (1.32±0.25)×108 | 80.49±0.84 |
| 0.3%胆盐0.3% bile salts | (1.81±0.50)×107 | (1.21±0.30)×107 | 66.85±0.46 |
| 人工胃液Artificial gastric fluid | (1.78±0.57)×108 | (1.43±0.43)×108 | 80.34±0.26 |
| 人工肠液Artificial bowel fluid | (1.18±0.62)×108 | (0.83±0.23)×108 | 70.34±0.68 |
2.6 羊源卷曲乳杆菌DY38的自聚集能力、共聚集能力和表面疏水性
表5 羊源卷曲乳杆菌DY38的自聚集能力、共聚集能力和表面疏水性Table 5 Auto-aggregation ability, co-aggregation ability and surface hydrophobicity of Lactobacillus crispatus DY38 from goats % |
| 项目 Item | 自聚集能力 Auto-aggregation ability | 共聚集能力 Co-aggregation ability | 疏水性 Surface hydrophobicity |
|---|---|---|---|
| 羊源卷曲乳杆菌DY38 Lactobacillus crispatus DY38 from goats | 64.83±0.17 | 62.81±0.38 | 80.69±0.43 |
2.7 羊源卷曲乳杆菌DY38对Caco-2细胞的黏附性能
图3 羊源卷曲乳杆菌DY38对Caco-2细胞的黏附性能A:与羊源卷曲乳杆菌DY38共培养的Caco-2细胞(1 000×);B:未与羊源卷曲乳杆菌DY38共培养的Caco-2细胞(1 000×)。 Fig.3 Adhesion property of Lactobacillus crispatus DY38 from goats to Caco-2 cells A: Caco-2 cells co-cultured with Lactobacillus crispatus DY38 form goats (1 000×); B: Caco-2 cells did not co-cultured with Lactobacillus crispatus DY38 from goats (1 000×). |
2.8 羊源卷曲乳杆菌DY38的细胞毒性
表6 感染羊源卷曲乳杆菌DY38和肠炎沙门氏菌SWUN3802后的Caco-2细胞活力Table 6 Viability of Caco-2 cells after infected with Lactobacillus crispatus DY38 form goats and Salmonella enteritidis SWUN3802 % |
| 感染菌株 Infected strains | 感染不同时间后Caco-2细胞活力 Viability of Caco-2 cells at different time after infection | ||||
|---|---|---|---|---|---|
| 2 h | 4 h | 6 h | 8 h | 12 h | |
| 肠炎沙门氏菌SWUN3802 Salmonella enteritidis SWUN3802 | 85.04±0.36c | 84.39±0.49c | 78.89±0.12c | 72.37±0.22c | 68.91±0.38c |
| 羊源卷曲乳杆菌DY38 Lactobacillus crispatus DY38 form goats | 98.66±0.13a | 97.89±0.23a | 95.88±0.32a | 95.48±0.21a | 95.38±0.15a |
| 肠炎沙门氏菌SWUN3802+ 羊源卷曲乳杆菌DY38 Salmonella enteritidis SWUN3802+ Lactobacillus crispatus DY38 form goats | 88.82±0.23b | 87.91±0.21b | 86.85±0.18b | 85.38±0.16b | 84.96±0.24b |
同列数据肩标不同小写字母表示差异显著(P<0.05)。 | |
Values in the same column with different small letter superscripts mean significant difference (P<0.05). |
2.9 羊源卷曲乳杆菌DY38的抗氧化能力
表7 羊源卷曲乳杆菌DY38对DPPH自由基、超氧阴离子自由基、羟自由基的清除率及其还原能力Table 7 DPPH·, O2-· and·OH savenging rates and reducing capacity of Lactobacillus crispatus DY38 from goats % |
| 羊源卷曲乳杆菌 DY38各组分 Components of Lactobacillus crispatus DY38 form goats | 羊源卷曲乳杆菌DY38的抗氧化能力 Antioxidant capacity of Lactobacillus crispatus DY38 from goats | |||
|---|---|---|---|---|
| DPPH自由基清除率 DPPH· savenging rate | 超氧阴离子 自由基清除率 O2-· savenging rate | 羟自由基清除率 ·OH savenging rate | 还原能力 Reducing capacity | |
| 发酵上清液 Fermentation supernatant | 89.43±0.32 | 10.85±0.08 | 62.54±0.63 | 8.67±0.17 |
| 菌悬液Bacterial suspension | 30.38±0.46 | 15.71±0.25 | 18.53±0.52 | 4.52±0.43 |
| 胞内提取物 Intracellular extract | 11.52±0.32 | 28.34±0.13 | 23.52±0.12 | 2.38±0.56 |
