Pune: A team of researchers from Shri Shiv Chhatrapati (SSC) College, Junnar, district Pune, have devised a novel biofilm possessing antibacterial quality to fight Aedes aegypti (yellow fever mosquito), the vector of the virus that causes zika, dengue and chikungunya, in humans. The team is a part of an international collaborative study.
Interestingly, the film coated with silver and gold nano-particles obtained from the silk protein of mulberry silk was able to completely kill the larva of Aedes aegypti. The scientists coated this film with nano-particles synthesised from mulberry grown locally in and around Junnar, located about 90 km from Pune. Silk is a fibre produced by silkworms which consists of two proteins, namely fibroin and sericin. This film was later subjected to controlled growth of larva, which was tested for eight days.
“The resultant nanosilver and nanogold-based fibroin solution and films were tested for antibacterial activity against various bacteria E coli, S aureus, K pneumonia, P aeruginosa and antifungal activity. Our synthesised silver and gold nanoparticles are effective against P aeruginosa, which is resistant to most of the present day antibiotics. Nanosilver-based solution exhibited an effective antimicrobial action against all these microbes as compared to nanogold solution,” said RD Chaudhari, Head of Zoology Research Centre of SSC College, Junnar.
“Additionally, nearly 100 per cent mortality of yellow fever mosquito larva in the water-insoluble film was obtained while the film of gold-based nanocomposite revealed 86-98 per cent mortality,” said Chaudhari.
According to the statistics provided by National Vector-Borne Disease Control Programme, there were over 50,131 cases of dengue and two lakh cases of chikungunya in the country during 2013-2017 (until December 17).
“The bio-nanocomposite material could restrict the growth of yellow fever mosquito. Other infections such as flavivirus, malaria, yellow fever, filariasis, schistosomiasis and Japanese encephalitis can automatically be curbed and effectively controlled,” said co-researcher, Professor Haiwon Lee from Hanyang University in South Korea.
Besides preventing mosquito breeding, Dr Chaudhari said, farmers, can hugely benefit from the sale of mulberry silk. This silk is mainly grown in Karnataka, Andhra Pradesh, West Bengal, Tamil Nadu, Maharashtra and Jammu and Kashmir, which accounts for 92 per cent of country's total mulberry raw silk production.
“If we can tap this abundant natural resource, available in the form of silk obtained from mulberry tree and Tusar silk, it can potentially become an additional income source for farmers, given that mulberry plant has a lifespan of 12 to 15 years,” said Chairman and Principal CR Mandlik, SSC College, Junnar.
“Also, since this tree can bear fruits at regular intervals, a cultivator can get an assured income which will support his regular income from the farm produce,” Chaudhari added.
In Maharashtra, Tusar silk is largely reared in Vidarbha region while mulberry is more commonly grown along the western ghats. Yet another benefit of using this film, the study team claims, is that it is biodegradable. The team tested this water for wheat cultivation and there were no side effects on it.
The team also included researchers Dinesh Amalnerkar from Hanyang University and former executive director of Centre for Electronics and Materials Energy Technology (C-MET), India, Manish Shinde from C-MET, Pune and Pramod Mane, SSC College, Junnar. The research was financially supported by Savitribai Phule Pune University (SPPU) and Indian Space Research Organisation (ISRO).