荞麦蜂花粉多酚对α-淀粉酶的抑制作用

Inhibition effect of buckwheat bee pollen polyphenols onα-amylase

蜂花粉多酚是一类能够有效降低血糖的天然物质。α-淀粉酶是高等生物体内血糖控制的关键酶,抑制其活性有助于控制餐后血糖。为探究蜂花粉多酚抑制α-淀粉酶发挥降糖活性的机制,本文以荞麦蜂花粉多酚(buckwheat bee pollen polyphenol,BBPP)为对象,采用比色法、荧光分光光度法研究BBPP对α-淀粉酶活性影响及其抑制机理。结果表明,BBPP能对α-淀粉酶产生较强的抑制作用,半抑制浓度(IC_(50))为2.00±0.06 mg/mL,抑制类型为可逆性混合型抑制。高温、强碱、光照以及高浓度氧化剂与还原剂等处理,均能降低BBPP对α-淀粉酶的抑制作用。在273~298 K和298~310 K时其结合过程分别为动态猝灭和静态猝灭。随着BBPP浓度增加,α-淀粉酶荧光最大发射波长产生蓝移,表明α-淀粉酶构象改变,疏水性增加。本研究发现荞麦蜂花粉多酚对α-淀粉酶具有较强抑制作用,对荞麦蜂花粉多酚的临床开发利用具有重要的理论参考价值。

Bee pollen polyphenols are a class of natural substances that can effectively lower blood sugar.α-Amylase is a key enzyme for blood glucose control in higher organisms,and inhibiting its activity can help control postprandial blood glucose.In this study,buckwheat bee pollen polyphenol(BBPP)was used as the sample to investigate the inhibition effect of BBPP on the activity ofα-amylase by UV-vis and fluorescence spectrometry.The results showed that BBPP had a strong inhibitory effect onα-amylase,with a half maximal inhibitory concentration(IC_(50))of 2.00±0.06 mg/mL,and a reversible mixed inhibition type.Moreover,all the treatments including high temperature,strong alkali,light and high concentration of oxidants and reducing agents could decrease the inhibition effect of BBPP onα-amylase.At the temperature of 273-298 K and 298-310 K,the binding process was dynamic quenching and static quenching,respectively.As the concentration of BBPP increased,the maximum emission wavelength ofα-amylase fluorescence had a blue shift,indicating that the conformation ofα-amylase altered and the hydrophobicity increased.In conclusion,BBPP has a strong inhibitory effect onα-amylase,which has important theoretical reference value for clinical development and utilization of buckwheat bee pollen polyphenol.