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Scientists invent silk food wrap that's biodegradable and could replace plastic cling film

Bananas and strawberries kept at room temperature for more than a week did not go off after they were coated with a near-invisible film made from silk

                                                                                                                        Ian Johnston

 Scientists have invented a cling film-like food wrap made from silk that can preserve fruit for more than a week, as a natural, biodegradable alternative to plastic.

International concern has been growing about plastic waste, particularly the amount that gets into the sea. One estimate is that by 2050 there will be more plastic than fish in the world's oceans.

Doctors have also warned that containers made from certain kinds of plastic could be harmful to health.

Now a team of biomedical engineers at Tufts University in the US have developed a technique that enables food to be coated with an almost invisible layer of fibroin, a protein found in silk, which helps make it one of nature's toughest materials.

The lead researcher, Professor Fiorenzo Omenetto, told The Independent that the world should probably move "towards processes that are more efficient and more naturally derived" and develop materials that "are closer to the things that surround us, rather than having more man-made, processed materials ... for the general well-being of our planet".

"It's a wise way of thinking about how we manage the resources of our planet, to maybe use renewable systems as opposed to non-renewable systems," he said.

"The pervasiveness of plastic and all the inorganic chemicals that leach out, albeit at very slow rates, can affect us in many ways."

When asked what the chances were that silk-derived products would replace plastics, Professor Omenetto said: "That's our dream."

However he said the use of plastic was widespread and "incredibly cost effective" so it might take some time to convince people to change.

The same team previously made a silk cup that could be used, at least once, for coffee as a possible replacement for plasticlined cardboard cups.

In a paper in the journal Scientific Reports, they described how strawberries and bananas could be preserved for a week or more.

The fruit is coated by dipping it in a liquid containing a tiny amount of fibroin, but the wrap could also be applied with a spray. The silk is produced naturally by worms of moths.

Strawberries left for seven days at room temperature became discoloured and went soft, but those coated with the silk protein stayed juicy and firm.

Available in: http://www.independent.co.uk/news/science/silk-plastic-cling-film-food-wrap-marine-pollution-food-fruit-vegetables-tufts-universityfiorenzo-a7017401.html. Access on: May 2016.

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Houston’s Poor Neighborhoods Could Be Prime Zika Real Estate

The World Health Organization (WHO) has warned of the potential for the explosive spread of the Zika virus through the Americas. Margaret Chan, the director of the WHO, advised that the Americas could be hit by 4 million cases of Zika this year. The outbreak of Zika virus now centered in Brazil has been linked to a sudden increase in severe birth defects including microcephaly, babies born with smaller heads and brains. The National Public Radio – USA (NPR) recently reported that other neurological problems, such as babies born blind, may also be linked to Zika. Researchers do not fully understand Zika or have not yet proven causality, but the circumstantial evidence connecting the Zika outbreak to the sudden, large increase in birth defects is very strong.

Reports quoted experts who said that Zika was a low risk to the United States because the U.S. doesn’t have the poverty and high population densities that have caused the explosive spread of Zika in Brazil. However, Dr. Peter Hotez, a tropical disease researcher who lives in Texas, has warned that poverty and high population density makes Houston highly vulnerable to a Zika outbreak. He warned that the whole Mexican Gulf coast is already sufferingfrom increasing levels of tropical diseases spread by mosquitoes, in particular dengue fever. Because Zika virus is related to dengue fever and has the same mosquito vector, the expansion of dengue in the Gulf coast region is a good indicator of the potential spread of Zika virus

Adapted from: <http://www.democraticunderground.com/

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 TEXT 1

  Houston’s Poor Neighborhoods Could Be Prime Zika Real Estate

The World Health Organization (WHO) has warned of the potential for the explosive spread of the Zika virus through the Americas. Margaret Chan, the director of the WHO, advised that the Americas could be hit by 4 million cases of Zika this year. The outbreak of Zika virus now centered in Brazil has been linked to a sudden increase in severe birth defects including microcephaly, babies born with smaller heads and brains. The National Public Radio – USA (NPR) recently reported that other neurological problems, such as babies born blind, may also be linked to Zika. Researchers do not fully understand Zika or have not yet proven causality, but the circumstantial evidence connecting the Zika outbreak to the sudden, large increase in birth defects is very strong.

Reports quoted experts who said that Zika was a low risk to the United States because the U.S. doesn’t have the poverty and high population densities that have caused the explosive spread of Zika in Brazil. However, Dr. Peter Hotez, a tropical disease researcher who lives in Texas, has warned that poverty and high population density makes Houston highly vulnerable to a Zika outbreak. He warned that the whole Mexican Gulf coast is already suffering from increasing levels of tropical diseases spread by mosquitoes, in particular dengue fever. Because Zika virus is related to dengue fever and has the same mosquito vector, the expansion of dengue in the Gulf coast region is a good indicator of the potential spread of Zika virus.

 Adapted from: <http://www.democraticunderground.com/

112796307>