Biodegradation of thermally oxidized polyethylene
Biodegradation of thermally oxidized polyethylene
复制标题
热氧化聚乙烯的生物降解
DOI：
10.1016/0141-3910(95)00040-s
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发表时间：
1995
影响因子：
5.9
通讯作者：
C. David
中科院分区：
文献类型：
--
作者：
M. Weiland;A. Daro;C. David
本文研究了热氧化聚乙烯（PE）在不同条件下的生物降解性：（1）在固体琼脂上，在四种真菌混合孢子的悬浮液存在下（2）在不同温度、含水量和堆肥物料性质的三个堆肥单元中进行堆肥;和（3）在三种链霉菌菌株（badius、setonii、viridosporus）或来自堆肥的微生物悬浮液存在下，在液体培养基（呼吸量烧瓶）中。定性证据的氧化PE膜的生物同化，获得与真菌和堆肥。随着PE分子量的降低，真菌对膜表面的覆盖率增加，当初始分子量在1500 ~ 600之间时，真菌对膜表面的覆盖率达到60%。与真菌和堆肥中，重要的表面侵蚀检测到由SEM与初始Mn约1000的样品。FTIR、DSC和GPC也观察到了重要的变化。最后一种方法在所有情况下都显示了在与微生物孵育之前不存在的高分子量部分的形成以及整个曲线向更高分子量的偏移。这是链缩合的证据，可能是由于在本工作中使用的工业堆肥装置中普遍存在的O2分压较低的纯热反应。它可能伴随着低分子量部分的生物同化。定量信息可通过呼吸量测定法获得。对于在液体培养基中进行的培养中存在的微生物的悬浮液从堆肥，生物降解是很重要的，当底物浓度很低（约0.006%）。尽管在这些条件下存在不可避免的大误差，但氧摄取是明显的，并且清楚地证明了样品的低分子量部分的生物降解。
The biodegradability of thermally oxidized polyethylene (PE) has been studied in various conditions: (1) on solid agar in the presence of a suspension of mixed spores of four fungi (Aspergillus niger, Penicillium funiculosum, Paecilomyces variotii and Gliocladium virens); (2) in three composting units differing in temperature, moisture content and the nature of the composted materials; and (3) in liquid medium (respirometric flasks) in the presence of three Streptomyces strains (badius, setonii, viridosporus) or of a suspension of microorganisms from compost. Qualitative evidence of bioassimilation of the oxidized PE films was obtained with fungi and in composts. Coverage of the film surface by fungi increases as the molecular weight of the PE is decreased and attains 60% when the initial Mnlies between 1500 and 600. With fungi and in compost, important surface erosion was detected by SEM for samples with initial Mnaround 1000. Important changes were also observed by FTIR, DSC and GPC. This last method revealed in all cases the formation of a high molecular weight fraction that was not present before incubation with microorganisms and a shift of the whole curve toward higher molecular weight. This is evidence of chain condensation probably due to purely thermal reaction at the low partial pressure of O2prevailing in the industrial composting units used in this work. It is probably accompanied by bioassimilation of the low molecular weight fraction. Quantitative information can be obtained by a respirometric method. For incubations performed in liquid medium in the presence of a suspension of microorganisms from compost, biodegradation was important when substrate concentration was very low (≈ 0.006%). Despite the presence of unavoidable large errors in these conditions, oxygen uptake was evident and biodegradation of the low molecular weight fraction of the sample was clearly demonstrated.