School of Food Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
School of Food Technology, Institute of Agricultural Technology, Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand.
Ultrason Sonochem. 2023 May;95:106372. doi: 10.1016/j.ultsonch.2023.106372. Epub 2023 Mar 15.
Broiler chicken tracheas are a co-product from chicken slaughterhouses which are normally turned into low value animal feed despite their high levels of collagen. Typical collagen extraction by acid and/or pepsin usually results in relatively low yield. Ultrasound-assisted extraction (UAE) could be a means to improve collagen yield. The objectives of this study were to investigate the effects of ultrasonic parameters on the yield and biochemical properties of trachea collagen (TC). Conventional extraction using acetic acid and pepsin for 48 h resulted in acid-soluble (AS) and pepsin-soluble (PS) collagen with a yield of 0.65% and 3.10%, respectively. When an ultrasound with an intensity of 17.46 W·cm was applied for 20 min, followed by acid extraction for 42 h (U-AS), the collagen yield increased to 1.58%. A yield of 6.28% was obtained when the ultrasound treatment was followed by pepsin for 36 h (U-PS). PS and U-PS contained collagen of 82.84% and 85.70%, respectively. Scanning electron microscopy images revealed that the ultrasound did not affect the collagen microstructure. All collagen samples showed an obvious triple helix structure as measured by circular dichroism spectroscopy. Fourier transform infrared spectroscopy indicated that the ultrasound did not disturb the secondary structure of the protein in which approximately 30% of the α-helix content was a major structure for all collagen samples. Micro-differential scanning calorimetry demonstrated that the denaturation temperature of collagen in the presence of deionized water was higher than collagen solubilized in 0.5 M acetic acid, regardless of the extraction method. All collagen comprised of α and α-units with molecular weights of approximately 135 and 116 kDa, respectively, corresponding to the type I characteristic. PS and U-PS collagen possessed higher imino acids than their AS and U-AS counterparts. Based on LC-MS/MS peptide mapping, PS and U-PS collagen showed a high similarity to type I collagen. These results suggest that chicken tracheas are an alternative source of type I collagen. UAE is a promising technique that could increase collagen yield without damaging its structure.
肉鸡气管是鸡肉屠宰场的一种副产物，尽管其胶原蛋白含量很高，但通常会被制成低价值的动物饲料。通常情况下，采用酸法和/或胃蛋白酶法提取胶原蛋白的收率相对较低。超声辅助提取（UAE）可能是提高胶原蛋白收率的一种方法。本研究的目的是探讨超声参数对气管胶原蛋白（TC）提取率和生化特性的影响。采用常规的乙酸和胃蛋白酶提取法提取 48 小时，得到酸溶性（AS）和胃蛋白酶溶性（PS）胶原蛋白，提取率分别为 0.65%和 3.10%。当超声强度为 17.46 W·cm 时，超声处理 20 分钟，再用酸提取 42 小时（U-AS），胶原蛋白收率提高到 1.58%。当超声处理后用胃蛋白酶提取 36 小时（U-PS）时，胶原蛋白收率达到 6.28%。PS 和 U-PS 中胶原蛋白含量分别为 82.84%和 85.70%。扫描电子显微镜图像显示，超声处理不影响胶原蛋白的微观结构。所有胶原蛋白样品均表现出明显的三螺旋结构，通过圆二色性光谱测量。傅里叶变换红外光谱表明，超声处理未干扰蛋白质的二级结构，所有胶原蛋白样品中约 30%的α-螺旋含量是主要结构。微差示扫描量热法表明，在去离子水中胶原蛋白的变性温度高于在 0.5 M 乙酸中溶解的胶原蛋白，无论采用何种提取方法。所有胶原蛋白均由α和α-单元组成，分子量分别约为 135 和 116 kDa，分别对应于 I 型特征。PS 和 U-PS 胶原蛋白的亚氨基酸含量高于其 AS 和 U-AS 对应物。基于 LC-MS/MS 肽图谱分析，PS 和 U-PS 胶原蛋白与 I 型胶原蛋白具有高度相似性。这些结果表明，鸡气管是 I 型胶原蛋白的替代来源。UAE 是一种有前途的技术，可以在不破坏其结构的情况下提高胶原蛋白的收率。
