College of Food Science and Technology, Huazhong Agricultural University, Wuhan, Hubei 430070, PR China.
Micron. 2011 Jan;42(1):36-41. doi: 10.1016/j.micron.2010.08.005. Epub 2010 Aug 22.
Microwave radiation and conductive heating were used to completely kill adult Tribolium castaneum (Coleoptera: Tenebrionidae) in wheat flour to protect the flour during storage without significantly effecting its quality. The microstructure of T. castaneum was analyzed to reveal the mechanisms leading to death under microwave and heat treatments. Microwave radiation and conductive heating had different effects on the microstructure of the cuticle of adult T. castaneum and on the ultrastructure of the cells of the epidermis, fat body, and midgut. Both treatments caused a large cavity to appear in the nucleus and the disappearance of mitochondria and the Golgi apparatus. After microwave treatment, there was little change in the surface microstructure but the epidermis was of uneven thickness and the four outer layers of the cuticle were thinner. Nuclear size was essentially unchanged, but fat body cells were fewer and coalesced together. In contrast, conductive heating led to a disordered arrangement of cells on the surface of T. castaneum and indistinct boundaries between layers of the cuticle. The nuclei were enlarged and the fat body cells noticeably fewer and indistinct with a scattered distribution. Thus, microwave treatment produced less severe effects on the surface microstructure and cellular ultrastructure of T. castaneum than did conductive heating. It is concluded that these cellular and surface changes were responsible for the death of T. castaneum.
微波辐射和传导加热被用来彻底杀死小麦粉中的成年赤拟谷盗（鞘翅目：拟步甲科），以在储存过程中保护面粉，而不会显著影响其质量。分析了 T. castaneum 的微观结构，以揭示微波和热处理导致死亡的机制。微波辐射和传导加热对成年 T. castaneum 的表皮细胞的细胞结构和表皮、脂肪体和中肠的超微结构有不同的影响。这两种处理都导致核内出现大空腔，线粒体和高尔基体消失。微波处理后，表皮表面的微观结构几乎没有变化，但表皮厚度不均匀，外四层角质层较薄。核大小基本不变，但脂肪体细胞数量减少并融合在一起。相比之下，传导加热导致 T. castaneum 表面细胞排列紊乱，角质层各层之间的边界不明显。细胞核增大，脂肪体细胞数量明显减少且分布分散。因此，与传导加热相比，微波处理对 T. castaneum 的表面微观结构和细胞超微结构的影响较小。可以得出结论，这些细胞和表面的变化是导致 T. castaneum 死亡的原因。
