Page 104 - Plastics News December 2019

tEChNoLogy

UNSW Sydney researchers Pune scientists discover fungi

develop packaging from banana strains that degrade polythene
plantation waste

hree scientists from Pune University have identified
Tfungi which can potentially help degrade polythene
wo researchers at the University of New South Wales and emerge as an answer to the plastic pollution crisis.
T(UNSW) Sydney have developed biodegradable and The research team, led by Avinash Ade at Savitribai
recyclable packaging material from banana plantation Phule Pune University, including Manisha Sangale
waste.UNSW School of Chemical Engineering associate
(Savitribai Phule Pune University) and Mohd Shahnawaz
(currently, with CSIR-Indian Institute of Integrative
Medicine, Jammu), had published a paper based on
collected samples from 12 different locations in five
coastal states — Kerala, Karnataka, Maharashtra,
Goa and Gujarat. The locations were plastic waste
dumping sites with growing mangroves surrounded by
marine water. From the soil samples collected — root-
soil where microorganisms colonise – the scientists
found ‘Aspergillus terreus’ and ‘Aspergillus sydowii’
fungi strain that are efficient polythene degraders.
The ‘Aspergillus sydowii’ fungi strain showed 94 per
professor Jayashree Arcot and professor Martina Stenzel cent reduction in tensile strength of polythene, the
were exploring ways that could help to introduce paper states.Commenting on the use of these fungi to
agricultural waste into the circular economy.The degrade polythene at a commercial level, Shahnawaz
researchers have selected banana-growing industry, which said, “This was a preliminary study at in vitro level. To
produces large amounts of organic waste. Only 12% of utilise these elite polythene degrading fungi at mass
the plant or fruit is used and the rest is discarded after level, we need to check their efficiency at in vivo level
harvest. Arcot said: “What makes the banana-growing (in life). If at in vivo level we get significant results,
business particularly wasteful compared to other fruit then we can recommend its usage to combat plastic
crops is the fact that the plant dies after each harvest. pollution at a mass level.” He added that the potential
“We were particularly interested in the pseudostems – application of
basically the layered, fleshy trunk of the plant, which is cut this study is that
down after each harvest and mostly discarded on the field. it reports the
Some of it is used for textiles, some as compost, but other most-efficient
than that, it is a huge waste.” The researchers focused on poly t h e n e
the pseudostems of the banana plant, which they thought degrading fungi
could prove to be a valuable source of cellulose. According and furthermore
to the researchers, the banana pseudostem could prove its non-toxic
to be an alternative to plastic bags and food packaging natur e. T he
In order to extract cellulose, pseudostem material was paper also lists
sourced from banana plants grown at the Royal Botanic the available
Garden Sydney. The pseudostem contains 90% water. It options fo r
can be dried and ground to a very fine powder. Stenzel polythene disposal such as incineration, recycling,
said: “We then take this powder and wash it with a very production of biodegradable plastic, and use of plastic
soft chemical treatment. This isolates what we call in construction of roads. But it also states that each
nano-cellulose, which is a material of high value with a of these methods has either deteriorating effects on
whole range of applications.“One of those applications the environment or needs to be studied economically.
that interested us greatly was packaging, particularly It says that among all the methods, biodegradation
single-use food packaging where so much ends up in a is considered the most accepted and eco-friendly
landfill.” Tests have proved that the material posed no method.
contamination risks and disintegrate in the soil.

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