[关键词]
[摘要]
为探究牦牛骨胶原蛋白多肽组分YBCP-2-2对酪氨酸酶的抑制方式,对其进行了抗氧化活性、Cu2+ 螯合能力、肽对酪氨酸单酚酶和二酚酶抑制动力学及酪氨酸酶荧光光谱影响等方面的分析。结果表明YBCP-2-2具有显著抗氧化能力,DPPH自由基和ABTS自由基的清除IC50分别为6.02 mg/mL和0.81 mg/mL,总还原力在8.00 mg/mL时吸光值达0.57,铜离子螯合能力也较为出色,IC50为3.22 mg/mL。YBCP-2-2对酪氨酸单酚酶具有明显迟滞效应并呈质量浓度依赖性,当抑制物质量浓度达到20.00 mg/mL时,反应初速度从0.012 OD475·min下降至0.0039 OD475·min;对酪氨酸二酚酶的抑制类型为混合竞争性抑制,Vmax和Km均随胶原蛋白肽质量浓度的变化而改变,抑制常数KI为0.58 mg/mL。YBCP-2-2能与酪氨酸酶发生相互作用导致酶蛋白荧光猝灭且引起荧光光谱从340.20 nm红移至351.60 nm。结果证明了胶原蛋白多肽具有较强的酪氨酸酶抑制活性,为完善肽类对酪氨酸酶抑制作用的理论研究提供了理论依据。
[Key word]
[Abstract]
In order to investigate the inhibition mode of the yak bone collagen peptide fraction, YBCP-2-2, it was subjected to an analysis encompassing its antioxidant activity, Cu2+ chelating capacity, kinetics pertaining to the peptide's inhibition of tyrosine mono- and di-phenolase, and the effect on tyrosinase via fluorescence spectroscopy. The results revealed that YBCP-2-2 was found to possess a significant antioxidant capacity, with the scavenging IC50 values being6.02 mg/mLand 0.81 mg/mL against DPPH radicals and ABTS radicals, respectively. Additionally, it exhibited a total reducing power absorbance value of 0.57 at 8.00 mg/mL. Furthermore, YBCP-2-2 was demonstrated to possess superior Cu2+ chelating capacity, with an IC50 of 3.22 mg/mL. The peptide was found to be significantly active in inhibiting Tyrosine monophenolase, exhibiting a noticeable retardation effect that was dependent on its mass concentration. When the inhibitor's mass concentration reached 20.00 mg/mL, the initial velocity of the reaction decreased from 0.012 OD475-min to 0.0039 OD475-min. The inhibition type on tyrosine diphenolase was identified as mixed competitive inhibition, with both Vmax and Km undergoing changes in response to alterations in the collagen peptide's mass concentration. The inhibition constant KI was determined to be 0.58 mg/mL. The interaction between YBCP-2-2 and tyrosinase resulted in a fluorescence burst of the enzyme protein, causing the fluorescence spectrum to undergo a red-shift from 340.20 nm to 351.60 nm. These findings conclusively proved that collagen peptides possess potent tyrosinase inhibitory activity, thereby providing a theoretical foundation for the study of the inhibitory effects of peptides on tyrosinase.
[中图分类号]
TS251.94??
[基金项目]