不同全蚕粉中的1-脱氧野尻霉素含量及其对小鼠血糖浓度的影响

Determination of 1-DNJ Content in Various Silkworm Powders and its Effects on Lowering Mouse Blood-glucose Level

为探讨全蚕粉中1-脱氧野尻霉素(1-deoxynojimycin,1-DNJ)含量与降血糖效果的关系以及蚕体内1-DNJ的来源,测定了7个家蚕品种或杂交组合以及用5个桑品种和不同叶质桑叶饲养5龄蚕制备的全蚕粉中1-DNJ含量,同时测定了由相应的全蚕粉配制的蚕粉复合物对小鼠食后1.5 h血糖值的影响。结果表明,不同家蚕品种以及用不同桑品种和不同叶质桑叶饲养家蚕制备的全蚕粉复合物的降血糖效果均存在显著差异,凡是降血糖效果显著的全蚕粉,1-DNJ含量都处于较高水平,而1-DNJ含量低的全蚕粉其降血糖效果均较差,但降血糖活性与1-DNJ含量之间并不存在显著正相关关系,说明全蚕粉中还存在其它降血糖活性成分。养蚕用桑中的1-DNJ含量与蚕体内1-DNJ含量存在高度正相关性,而且用不含桑叶粉的人工饲料饲养的家蚕幼虫不含1-DNJ,因此证实了蚕体内的1-DNJ来源于桑叶,家蚕本身不能产生1-DNJ。

In this study, the silkworm powder＇s 1-DNJ （1-deoxynojimycin） content from 7 silkworm varieties, 5 mulberry varieties and mulberry leaves of various leaf orders were determined not only for the relationship between 1-DNJ content and the effect of lowering mouse blood-glucose level, but also for 1-DNJ source in silkworms. Besides, the influence of silkworm powder compound made from the corresponding silkworms on mouse 1.5 h postprandial blood-glucose level was measured. Results indicated that there existed significant difference in the effect of lowering blood-glucose level between different silkworm varieties, mulberry varieties and mulberry leaves of various leaf orders. The effects were related to 1-DNJ content in all the silkworm powders studied. All silkworm powder compounds which exhibited better effects had higher 1-DNJ content. Accordingly, when the silkworm powder compound has a lower 1-DNJ content, it had worse effect on lowering blood-glucose level. However, no direct significant positive correlation was observed between 1-DNJ content and the effect of lowering blood-glucose level, meaning that there existed other components in the silkworm powder which also exhibit blood-glucose lowering effect. A significant positive correlation was observed between 1-DNJ content in silkworm and in mulberry. Moreover, 1-DNJ was not found in silkworms fed with artificial diet which did not contain mulberry leaf powder. This proved that silkworms obtain 1- DNJ from mulberry leaves. They could not make 1-DNJ by themselves.