Nakatani Hisayuki, Yamaura Yuto, Mizuno Yuma, Motokucho Suguru, Dao Anh Thi Ngoc, Nakahara Hiroyuki
Graduate School of Integrated Science and Technology Chemistry and Materials Engineering Program, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
Organization for Marine Science and Technology, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
Polymers (Basel). 2024 Jun 9;16(12):1632. doi: 10.3390/polym16121632.
A degradation mechanism of polystyrene (PS) in mealworms reared on expanded PS (EPS) was investigated by its decrease in molecular weight and change in chemical structure. A 33% decrease in molecular weight was observed for the digested PS in the frass after 1 week of feeding to mealworms. The FT-IR and py-GC/MS spectra of the digested PS showed radical oxidative reactions taking place in the mealworm body. The presence of hydroperoxide, alcohol and phenol groups was confirmed, and dimer fragments of styrene with quinone and phenol groups were obtained. The decrease in molecular weight and the alternation of benzene rings indicated that autoxidation and quinonization via phenolic intermediates occurred simultaneously in the mealworm body. The survival rate of mealworms reared on EPS was higher than that of starved worms, indicating that EPS was a nutrient source. However, no weight gain was observed in mealworms fed EPS alone. Comparison with the mixed diets with bran or urethane foams (PU) indicated that protein, phosphorus and magnesium components absent from EPS were required for mealworm growth.
通过测定聚苯乙烯（PS）分子量的降低及其化学结构的变化，研究了以发泡聚苯乙烯（EPS）饲养的黄粉虫体内PS的降解机制。给黄粉虫喂食1周后，粪便中消化后的PS分子量下降了33%。消化后PS的傅里叶变换红外光谱（FT-IR）和热解气相色谱/质谱（py-GC/MS）谱表明，黄粉虫体内发生了自由基氧化反应。证实了过氧化氢、醇和酚基团的存在，并获得了带有醌和酚基团的苯乙烯二聚体片段。分子量的降低和苯环的变化表明，黄粉虫体内同时发生了通过酚类中间体的自动氧化和醌化反应。以EPS饲养的黄粉虫存活率高于饥饿的黄粉虫，这表明EPS是一种营养源。然而，单独喂食EPS的黄粉虫体重并未增加。与添加麸皮或聚氨酯泡沫（PU）的混合饲料相比，表明EPS中缺乏的蛋白质、磷和镁成分是黄粉虫生长所必需的。
