体外消化模型中酸乳β-酪啡肽-7和β-酪啡肽-5的释放及阿片活性

Release of β-Casomorphin-7 and β-Casomorphin-5 and Opiate Activity from Yogurt in Vitro Digestion Model

酸乳经过人体消化可在胃肠中产生具有舒缓紧张情绪的β-酪啡肽(β-casomorphin,β-CM),为探究其在胃肠道中的释放量及其生物活性,本实验采用体外消化模型,模拟酸乳在体内的消化过程,采用高效液相色谱法检测β-CM-7、β-CM-5的释放;并用NG108-15神经杂交瘤细胞体外实验和小鼠体内实验测定其阿片活性。结果:在模拟胃消化液、胰消化液中,酸乳经消化释放的β-CM-7质量浓度分别是40.24、47.81μg/mL,β-CM-5质量浓度分别是88.00、82.04μg/mL。两种酸乳消化液均能降低NG108-15细胞内腺苷酸环化酶活力,且此作用可被纳洛酮逆转,体现了β-CM的阿片活性。小鼠在注射酸乳胃消化液30 min后达到最强的镇痛活性,痛阈提高率达到59.80%;注射纯化后的高剂量酸乳胃消化液使小鼠的平均游泳时间延长了18.94 min,表明酸乳胃消化液具有较好的抗疲劳作用。结论:人类在饮用酸乳后体内产生了β-CM,且酸乳β-CM具有阿片活性,能够对人体起到镇静舒缓、抗疲劳等功效。

Yogurt can be digested in the gastrointestinal tract of humans to produce β-casomorphin(β-CM), which is believed to be able to relieves emotional tensions. In order to explore its release in the gastrointestinal tract and biological activity, an in vitro digestion model was used to simulate the digestion of yogurt in the body. The release of β-CM-7 and β-CM-5 was monitored by high performance liquid chromatography(HPLC);the opiate activity was measured by NG108-15 neurohybridoma cell in vitro assay and mouse behavioral test. After digestion in simulated gastric and pancreatic juices, the concentrations of β-CM-7 released were 40.24 and 47.81 μg/mL, respectively;the concentrations of β-CM-5 released were 88.00 and 82.04 μg/m L, respectively. Both digests could reduce the intracellular cAMP level in NG108-15 cells, which could be reversed by naloxone, reflecting the opiate activity of β-CM. The mouse experiments showed that the strongest analgesic activity was achieved at 30 minutes after injection of the gastric digest, giving an increase in pain threshold of 59.80%. Ingestion of the high-dose purified gastric digest prolonged the average swimming time of mice by 18.94 min, indicating good anti-fatigue effect. The experimental results show that β-CM with opiate activity and analgesic and anti-fatigue effects is produced from yogurt when ingested into in the body.