美国国家公共电台 NPR Replacing Plastic: Can Bacteria Help Us Break The Habit?

 

STEVE INSKEEP, HOST:

If a civilization is remembered for what it leaves behind for later eras to see, our time might be known as the plastic age. A Silicon¹ Valley startup is trying to get the plastic out of clothing and put something else in, something that will not last centuries. NPR's Christopher Joyce reports on their experiment in, of all places, a sewage treatment plant.

CHRISTOPHER JOYCE, BYLINE²: Molly Morse runs a company in California that makes something called a biopolymers. They're like plastic but made in nature by living things. She calls her company Mango Materials, after her favorite fruit. She says she wanted to sound different.

MOLLY MORSE: We're, if you didn't notice, not your typical Silicon Valley startup company. Like, we're manufacturing polymers at the wastewater treatment plant. We're not a bunch of guys in a garage coding.

JOYCE: So how did this come to be? Well, when Molly Morse was in elementary school, she went to an aquarium³ and stumbled on an exhibit about plastic trash floating in the ocean.

MORSE: And there was this huge, gigantic, like, fish tank-type structure full of clamshells - like Styrofoam clamshells from McDonald's. And I was floored - like, completely horrified⁴. Like, it changed my life. And I was like, that is freaking ridiculous, and I'm going to change it.

JOYCE: She followed through. Morse went to Stanford University and got a Ph.D. in environmental engineering. At a scientific conference in 2006, she met this young engineer, Anne Schauer-Gimenez.

ANNE SCHAUER-GIMENEZ: I mean, I think we were up till, like, 4 in the morning or something just talking about research and how this process works.

JOYCE: The process was how to make biopolymers. These are malleable⁵ materials similar to plastic, but they're made by living things, like cellulose from trees or silk from silkworms. And the bonus is biopolymers can be broken down into natural substances. The two engineers looked for ways to brew⁶ up batches⁷ of this stuff. They settled on bacteria, special kinds that make their own biopolymers, especially, says Morse, if you overfeed them.

MORSE: If we were to get really fat from eating a lot of ice cream or chocolate, we accumulate fat inside our bodies. These bacteria, same thing.

JOYCE: Schauer-Gimenez went for that.

SCHAUER-GIMENEZ: To me, microorganisms kind of run the show on planet Earth anyway. So why not let them help us with this process?

JOYCE: But the bacteria need lots of food to do that, and that's why they ended up at a sewage treatment plant in Redwood City, Calif. For the bacteria, sewage is food - or at least the methane⁸ gas from sewage. Treatment plants usually burn off the methane or just vent⁹ it into the air. Here, it's fed to bacteria.

ALLISON PIEJA: So this is where the magic happens in terms of the fermentation.

JOYCE: Engineer Allison Pieja is the third member of the Mango team. She's the bug¹⁰ expert and nurtures¹¹ the bacteria in a fermenter, kind of like a big beer keg with pipes sticking in it like IV drips.

PIEJA: We add the methane and oxygen continuously and kind of drip in our secret sauce based on how the bacteria are growing.

JOYCE: The secret sauce is an additive¹² that the team developed to keep the process going. Eventually, they bust¹³ open the bacteria and harvest the biopolymer. So far, they've shipped 1,700 pounds of that biopolymer to companies to test it in packaging and textiles. In a boardroom at the sewage plant, Morse shows me the results.

MORSE: So this was our fiber¹⁴ grade.

JOYCE: Brightly colored threads, plastic-y (ph) like polyester maybe. The hope is to weave the biopolymer into clothing to replace regular plastics - biodegradable clothing, which, says Schauer-Gimenez, freaks people out.

SCHAUER-GIMENEZ: Oh, my gosh. You're going to make a swimsuit out of your material. I'm going to go in the ocean, and it's going to biodegrade off of my body. And I'm like no, no, no, no, no. It doesn't quite work like that.

JOYCE: Biopolymers need warm temperatures and the right bacteria around to chew them up, and it takes weeks or months of constant exposure. Some kinds of biopolymers, ones made from plant materials like corn, take much longer to degrade, and that's given them a bad reputation.

RAMANI NARAYAN: Making a statement - biodegradable - that is misleading, especially to the general public.

JOYCE: Ramani Narayan is a chemical engineer at Michigan State University. He says the longer something takes to biodegrade, the longer it's litter.

NARAYAN: In that intervening period, it is going to have impacts. And that is what needs to be carefully considered.

JOYCE: Theoretically, biopolymers could be recycled. But Narayan points out that the recycling industry in the U.S. is already overwhelmed. Less than 10% of plastic currently gets recycled. Some research says even less.

NARAYAN: If we don't have the right waste management infrastructure¹⁵ in play, then all the things we do at the top end of it is going to be useless.

JOYCE: The Mango entrepreneurs say their biopolymer will break down faster than others and doesn't need to be recycled. Morse does acknowledge that there's a long way to go to get these biopolymers mainstreamed. In the meantime, she urges people to use less plastic and reuse things instead of throwing them away. But she's following her childhood dream to find something better than plastic.

Christopher Joyce, NPR News.

1 silicon   

n.硅(旧名矽)

参考例句：

• This company pioneered the use of silicon chip.这家公司开创了使用硅片的方法。
• A chip is a piece of silicon about the size of a postage stamp.芯片就是一枚邮票大小的硅片。

2 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

3 aquarium   

n.水族馆，养鱼池，玻璃缸

参考例句：

• The first time I saw seals was in an aquarium.我第一次看见海豹是在水族馆里。
• I'm going to the aquarium with my parents this Sunday.这个星期天，我要和父母一起到水族馆去。

4 horrified   

a.(表现出)恐惧的

参考例句：

• The whole country was horrified by the killings. 全国都对这些凶杀案感到大为震惊。
• We were horrified at the conditions prevailing in local prisons. 地方监狱的普遍状况让我们震惊。

5 malleable   

adj.(金属)可锻的;有延展性的；(性格)可训练的

参考例句：

• Silver is the most malleable of all metals.银是延展性最好的金属。
• Scientists are finding that the adult human brain is far more malleable than they once thought.科学家发现成人大脑的可塑性远超过他们之前认识到的。

6 brew   

v.酿造，调制

参考例句：

• Let's brew up some more tea.咱们沏些茶吧。
• The policeman dispelled the crowd lest they should brew trouble.警察驱散人群，因恐他们酿祸。

7 batches   

一批( batch的名词复数 )； 一炉； （食物、药物等的）一批生产的量； 成批作业

参考例句：

• The prisoners were led out in batches and shot. 这些囚犯被分批带出去枪毙了。
• The stainless drum may be used to make larger batches. 不锈钢转数设备可用来加工批量大的料。

8 methane   

n.甲烷，沼气

参考例句：

• The blast was caused by pockets of methane gas that ignited.爆炸是由数袋甲烷气体着火引起的。
• Methane may have extraterrestrial significance.甲烷具有星际意义。

9 vent   

n.通风口，排放口；开衩；vt.表达，发泄

参考例句：

• He gave vent to his anger by swearing loudly.他高声咒骂以发泄他的愤怒。
• When the vent became plugged,the engine would stop.当通风口被堵塞时，发动机就会停转。

10 bug   

n.虫子；故障；窃听器；vt.纠缠；装窃听器

参考例句：

• There is a bug in the system.系统出了故障。
• The bird caught a bug on the fly.那鸟在飞行中捉住了一只昆虫。

11 nurtures   

教养，培育( nurture的名词复数 )

参考例句：

• Art nurtures the soul and culture cultivates the mind. 艺术滋润心灵，文化陶冶情操。
• Who first loves and nurtures us and takes care of every need. 是谁先爱上我们，哺育我们，对我们无微不至。

12 additive   

adj.附加的；n.添加剂

参考例句：

• Colour is often an additive in foods.颜料经常是各种食物中的添加物。
• Strict safety tests are carried out on food additives.对食品添加剂进行了严格的安全检测。

13 bust   

vt.打破；vi.爆裂；n.半身像；胸部

参考例句：

• I dropped my camera on the pavement and bust it. 我把照相机掉在人行道上摔坏了。
• She has worked up a lump of clay into a bust.她把一块黏土精心制作成一个半身像。

14 fiber   

n.纤维，纤维质

参考例句：

• The basic structural unit of yarn is the fiber.纤维是纱的基本结构单元。
• The material must be free of fiber clumps.这种材料必须无纤维块。

15 infrastructure   

n.下部构造，下部组织，基础结构，基础设施

参考例句：

• We should step up the development of infrastructure for research.加强科学基础设施建设。
• We should strengthen cultural infrastructure and boost various types of popular culture.加强文化基础设施建设，发展各类群众文化。