冷藏大黄鱼肌肉蛋白质的生化特性及降解规律

Biochemical Properties and Degradation Rule of Muscle Protein from Large Yellow Croaker(Pseudosciaena crocea) during Chilled Storage

为探讨大黄鱼冷藏过程中肌肉蛋白质生化特性及降解规律,筛选能够表征大黄鱼新鲜度的相关蛋白,以0℃冷藏的大黄鱼肌动球蛋白的生化特性和蛋白质SDS-PAGE为指标进行研究。结果表明,在冷藏过程中,大黄鱼肌肉蛋白质生化特性发生了明显变化,主要表现为肌动球蛋白盐溶性、巯基含量以及Ca2＋-ATPase活性等指标随着贮藏时间的延长逐渐下降,而表面疏水性在贮藏初期明显增加。总可溶性蛋白中16~17 ku条带,水溶性蛋白中22~23 ku条带,低盐溶性蛋白中35~36 ku条带以及高盐溶性蛋白中的肌球蛋白重链（MHC）、肌动蛋白（Actin）、原肌球蛋白、33~34 ku条带随着贮藏时间的延长发生明显的变化。这7个条带代表的蛋白或肽类有望作为大黄鱼冷藏过程中潜在的新鲜度指示蛋白。

In order to study biochemical properties and degradation rule of muscle protein from large yellow croaker （Pseudosciaena crocea） during chilled storage, and research the protein indicator of freshness. The biochemical properties of actomyosin and SDS-PAGE analysis were determined during refrigerated storage at 0 ℃. The results showed that the biochemical characteristics of large yellow croaker muscle changed obviously during refrigerated storage. The salt-solubili- ties, SH contents, as well as Ca^2＋-ATPase activities of actomyosin obviously decreased during storage time, while surface hydrophobieity increased sharply in the initial phase of storage. The density of 16-17 ku protein band in total soluble proteins, 22-23 ku protein band in total soluble proteins, 35-36 ku protein band in low-salt soluble proteins, MHC, actin, tropomysion, 33-34 ku protein band in high-salt soluble proteins changed significantly during the storage time. Therefore, these seven bands could be potential protein indicators of freshness.