Natural fiber exoskeletons of insects and arthropods. In shells and exoskeletons, the chitin fibers contribute to their hierarchical structure. In nature, pure chitin (100% acetylation) does not exist. It instead exists as a copolymer with chitin's deacetylated derivative, chitosan. When the acetylized composition of the copolymer is over 50% acetylated it is chitin. This copolymer of chitin and chitosan is a random or block copolymer. Chitosan is a deacetylated derivative of chitin. When the acetylized composition of the copolymer is below 50% it is chitosan. Chitosan is a semicrystalline “polymer of β-(1-4)-2-amino-2-deoxy-D-glucose”. One difference between chitin and chitosan is that chitosan is
Fungi of Australia came to Australia over the past couple of centuries brought no strong fungal cultural traditions of their own. Fungi have also been largely overlooked in the scientific exploration of Australia. Since 1788, research on Australian fungi, initially by botanists and later by mycologists, has been spasmodic and intermittent. At governmental level, scientific neglect of Australian fungi continues: in the country's National Biodiversity Conservation Strategy for 2010-2030, fungi are mentioned only once, in the caption of one illustration, and some states currently lack mycologists in their respective fungal reference collections. The exact number of fungal species recorded from Australia is not