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Mealworms are the new champions in the plastic-eating stakes May 24th 2018 PLASTIC production has tripled over the past 25 years, and the mess it causes has risen commensurately. Recycling is one option. Another is biology, and with that in mind researchers have been hunting for creatures that can digest plastics. Several species of fungi and bacteria can do the job, but only slowly. Now Anja Brandon, a student at Stanford University, and her research supervisor, Craig Criddle, have found that bacteria in the guts of mealworms can break down polymers much more quickly. 在过去的25年里，塑料的产量增加了三倍，它造成的脏乱也相应地增加了。回收是一种选择，另一种选择是生物学，基于这一点，研究人员一直在寻找能够消化塑料的生物。一些真菌和细菌生物种类可以做到这一点，但速度很慢。现在，斯坦福大学的学生安娜·布兰登和她的导师克雷格·克里德尔发现，粉虱体内的细菌可以更快地分解聚合物。 Other researchers had already found that mealworms can digest a particular plastic called polystyrene. Ms Brandon and Dr Criddle wondered whether polystyrene was uniquely palatable, or whether the bacteria in the worms’ guts might be able to eat other sorts of plastic, too. To check, they turned to polyethylene, which is both more common than polystyrene and very different in chemical terms. If the worms found it nutritious as well, that would suggest their tastes might be usefully wide-ranging. 其他研究人员已经发现，粉虱可以消化一种叫做聚苯乙烯的特殊塑料。布兰登和克里斯德尔博士想知道，聚苯乙烯是否具有独特的美味，或者粉虱体内的细菌是否也能吃其他种类的塑料。为了验证这一点，他们转向了聚乙烯，聚乙烯比聚苯乙烯更常见，而且化学术结构也非常不同。如果这些虫子也觉得它很有营养，那就说明它们的口味可能很丰富。 As they describe in Environmental Science & Technology, the researchers divided their worms into groups. Some were given 1.8 grams of either polyethylene or polystyrene. Some were given both. Others had their plastic meals supplemented with wheat bran. (Wheat bran had been found to increase the rate at which mealworms could digest polystyrene). A control group of worms was fed only bran. 正如他们在《环境科学与技术》期刊上所描述的，研究人员把他们的蠕虫分成了几组。一些组得到了1.8克聚乙烯或聚苯乙烯，一些组两种塑料都给了。还有一些组的塑料餐中添加了麦麸(麦麸被发现可以提高粉虱消化聚苯乙烯的速度)，一个对照组的蠕虫子只吃麦麸。 More than 90% of the worms survived the 32-day experiment. Those fed only polyethylene found it very agreeable, polishing off 0.87 of their 1.8-gram helping. That was significantly more than the worms eating polystyrene, who managed just 0.57 grams of the stuff. Best of all were the worms that were given bran with their plastic. They chewed through 1.1 grams of polyethylene and 0.98 grams of polystyrene. 超过90%的蠕虫在32天的实验中存活了下来。那些只吃聚乙烯的虫子觉得很舒服，他们消灭了1.8克食物中的0.87克，这比那些只吃了0.57克聚苯乙烯的虫子要多得多。结果最好的是麦麸和塑料混合的那组虫子。他们吃掉了1.1克聚乙烯和0.98克聚苯乙烯。 Nor were the insects merely chewing up the plastics and then passing them in their faeces. Instead, chemical reactions in their guts were converting them into carbon dioxide. The conversion rate was low at first, but by the end of the experiment the worms fed polyethylene were converting 50% of it into gas and those fed polystyrene were converting 45%. 这些虫子也不是仅仅是咀嚼塑料，然后将它们转换成粪便。相反，它们体内的化学反应将它们转化为二氧化碳。一开始转化率很低，但实验结束时，喂食聚乙烯的虫子将50%的乙烯转化为气体，喂食聚苯乙烯的虫子将其45%转化为气体。 Ms Brandon and Dr Criddle theorised that the bacterial ecosystems inside the insects’ guts were changing to fit their unusual diets. They dissected the worms at the end of the experiment and compared the gut fauna of those that had been eating plastics with the fauna found in the control group. They found big differences, with several types of bacteria being more common in the guts of mealworms that had been fed plastic. 布兰登和克里德尔博士的理论认为，昆虫肠道内的细菌生态系会发生变化，以适应它们异常的饮食习惯。在实验结束时，他们解剖了这些蠕虫，并将食用塑料的动物的肠道动物群与对照组的动物群进行了比较。他们发现了很大的不同，在食用塑料的粉虱的肠道中，有几种细菌更为常见。 The researchers argue that not only are mealworms probably capable of digesting a wide range of plastics, but that the protean nature of their gut bacteria should allow them to specialise in a particular sort relatively quickly. A small population of a thousand worms, they reckon, might manage to devour 0.32 grams of polyethylene or 0.28 grams of polystyrene in a day. That is still not lightning fast. But it is quicker than waiting for it to break down in a landfill. 研究人员认为，粉虱不仅可能够消化大量的塑料，它们肠道千变万化的细菌特性应该能让它们能对否一特定塑料的消化相对较快。他们估计，一小群一千只蠕虫一天就能吃掉0.32克聚乙烯或0.28克聚苯乙烯。这虽然不是闪电般的速度。但这比在垃圾填埋场等待分解要快得多。 英文部分来自《经济学人》杂志
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