Chitin and Chitosan have been extracted from lobster waste and used in medicine and biomedicine by a team from the University of Havana. These researchers’ work has led to the development of a procedure to obtain surgical materials with great healing and antiseptic properties.

Chitin is a polymer very common in nature as part of animals’ and plants’ physical structures. Only cellulose is more abundant than chitin, which makes this compound a highly important renewable resource that can easily be found in arthropods, insects, arachnids, molluscs, fungus and algae.

"This procedure involves using chitosan to cover surgical threads and lint, into which antibiotics are injected. By doing this, we obtain medical materials with both antimicrobial and healing properties and, as they are covered in a natural polymer, with a higher degree of biocompatibility." states Professor Carlos Andrés Peniche Covas from the University of Havana. Research shows that such properties remained unmodified after sterilisation.

The fishing industry in Cuba generates great amounts of lobster waste, “a pollutant rich in proteins and chitin”, states Peniche. This group extracted chitin and chitosan from such waste, in collaboration with the Spanish Centre for Scientific Research (CSIC), the Complutense University in Madrid (Spain) and the Mexican Research Centre for Food and Development.

Prof. Peniche points out that "this work allows for the first accurate and comprehensive results of a university study on chitin and chitosan. The study starts at the extraction of these compounds from polluting waste of the Cuban fishing industry and it goes on to cover these products’ characterisation through traditional techniques and some more innovative ones, the study of their properties, the development of new by-products and the testing of their practical applications in areas useful for this Caribbean country, such as agriculture and biomedicine."

Two new types of surgical thread were produced in collaboration with the Cuban Superior Institute of Military Medicine "Dr. Luis Díaz Soto": Agasut-Q, covered with chitosan (healing properties) and Agasut-QE, covered with chitosan and streptomycin (healing and antimicrobial properties). After preclinical and clinical trials were approved, both surgical thread types were introduced and successfully used in several Cuban hospitals.

They also applied their study to agriculture. In cooperation with the Cuban National Centre for Agricultural and Livestock Health (CENSA), this group worked in “seed coating to boost farming yields as well as in encapsulation of somatic embryos to design artificial seeds".

In trials, tomato seeds of variety 1-17[140] were coated with chitosan. Under laboratory conditions, treated seeds showed significantly higher growth speed and percentage of successful germination when compared to non-treated seeds.

In Prof. Peniche’s words, the research group concluded that "chitosan works as a bio-stimulant in tomato seed treatment by producing better seed germination and greater plant height, stem thickness and dry mass about a week earlier than usual". Chitosan proved to be a natural polymer with great film-generating capacity, apart from other highly interesting properties: chitosan does not produce polluting substances, it is non-toxic and biocompatible.

Source: University of Granada