Qu Yunyao, Kim Bum-Jin, Koh Jeewon, Dallas David C
Department of Food Science & Technology, Oregon State University, Corvallis, OR 97331, USA.
Nutrition Program, School of Biological and Population Health Sciences, College of Public Health and Human Sciences, Oregon State University, Corvallis, OR 97331, USA.
Foods. 2023 Jan 8;12(2):299. doi: 10.3390/foods12020299.
Kappa-casein-derived caseinomacropeptide (CMP)-a 64-amino-acid peptide-is released from kappa-casein after rennet treatment and is one of the major peptides in whey protein isolate (WPI). CMP has anti-inflammatory and antibacterial activities. It also has two major amino acid sequences with different modifications, including glycosylation, phosphorylation, and oxidation. To understand the potential biological role of CMP within the human body, there is a need to examine the extent to which CMP and CMP-derived fragments survive across the digestive tract, where they can exert these functions. In this study, three solid-phase extraction (SPE) methods-porous graphitized carbon (PGC), hydrophilic interaction liquid chromatography (HILIC), and C18 chromatography-were evaluated to determine which SPE sorbent is the most efficient to extract intact CMP and CMP-derived peptides from WPI and intestinal digestive samples prior to LC-MS/MS acquisition. The C18 SPE sorbent was the most efficient in extracting intact CMP and CMP-derived peptides from WPI, whereas the PGC SPE sorbent was the most efficient in extracting CMP-derived peptides from intestinal digesta samples.
κ-酪蛋白衍生的酪蛋白巨肽（CMP）——一种由64个氨基酸组成的肽——在凝乳酶处理后从κ-酪蛋白中释放出来，是乳清蛋白分离物（WPI）中的主要肽类之一。CMP具有抗炎和抗菌活性。它还具有两种经过不同修饰的主要氨基酸序列，包括糖基化、磷酸化和氧化。为了了解CMP在人体内的潜在生物学作用，有必要研究CMP及其衍生片段在消化道中存活的程度，因为它们可以在消化道发挥这些功能。在本研究中，评估了三种固相萃取（SPE）方法——多孔石墨化碳（PGC）、亲水作用液相色谱（HILIC）和C18色谱——以确定哪种SPE吸附剂在进行LC-MS/MS分析之前，从WPI和肠道消化样品中提取完整的CMP及其衍生肽最为有效。C18 SPE吸附剂从WPI中提取完整的CMP及其衍生肽最为有效，而PGC SPE吸附剂从肠道消化物样品中提取CMP衍生肽最为有效。
