Qiao Jiangtao, Wang Xueyu, Liu Liqiang, Zhang Hongcheng
Institute of Apicultural Research, Chinese Academy of Agricultural Sciences , Beijing 100093, China.
College of Life Sciences and Food Engineering, Hebei University of Engineering , Handan 056021, China.
J Agric Food Chem. 2018 Feb 28;66(8):1881-1888. doi: 10.1021/acs.jafc.7b04955. Epub 2018 Feb 12.
Royal jelly possesses numerous functional properties. Improper storage usually causes bioactivity loss, especially queen differentiation activity. To determine changes in royal jelly, we investigated nonenzymatic browning and protein changes in royal jelly during room-temperature storage from 1 to 6 months. Our results indicate that royal jelly experiences nonenzymatic browning and protein aggregation. The products of nonenzymatic browning dramatically increased, especially N-carboxymethyl lysine (CML) with growth of approximately 7-fold. We speculate that CML may be recognized as a freshness marker for royal jelly. Our results also demonstrate that the major royal jelly protein 1 (MRJP1) monomer gradually aggregated with MRJP1 oligomers into new oligomers of about 440 and 700 kDa. This suggests that the reduction of MRJP1 monomer may be attributable to aggregation. We provide the novel explanation that the differentiation loss of royal jelly may be due to the aggregation of MRJP1 limiting the honeybees' ability to digest and absorb royal jelly.
蜂王浆具有多种功能特性。储存不当通常会导致生物活性丧失，尤其是蜂王分化活性。为了确定蜂王浆的变化情况，我们研究了蜂王浆在室温下储存1至6个月期间的非酶褐变和蛋白质变化。我们的结果表明，蜂王浆会发生非酶褐变和蛋白质聚集。非酶褐变产物显著增加，尤其是N-羧甲基赖氨酸（CML），其含量增长了约7倍。我们推测CML可能被视为蜂王浆新鲜度的标志物。我们的结果还表明，主要蜂王浆蛋白1（MRJP1）单体逐渐聚集，与MRJP1寡聚体形成约440和700 kDa的新寡聚体。这表明MRJP1单体的减少可能归因于聚集。我们提供了一种新的解释，即蜂王浆分化活性的丧失可能是由于MRJP1的聚集限制了蜜蜂消化和吸收蜂王浆的能力。
