<?xml version="1.0" encoding="utf-8"?><!DOCTYPE Zthes SYSTEM "http://zthes.z3950.org/xml/zthes-05.dtd">  <Zthes><term><termId>31316737</termId><termName>chitosan</termName><termType>PT</termType><termNote><![CDATA[ Chitosan is the deacetylated form of chitin, the chief component in the exoskeletons of crustaceans, insects, and beetles. It is used in horticulture and agriculture as a biopesticide, and plant growth enhancer; and in medicine as a coagulant. As a sprayed coating, cyanoethylated chitosan is used to protect historic paper material. Chitosan is also found as an organic component incorporated into polymer materials to form a self-healing coating which promises to render the painted surfaces it is applied to scratch-free. ]]></termNote><termCreatedDate>2026-03-30 20:25:17</termCreatedDate><relation><relationType>BT</relationType><termId>31303905</termId><termName>chitin</termName><termType>PT</termType></relation><relation><relationType>NT</relationType><termId>31340183</termId><termName>carboxymethyl chitosan</termName><termType>PT</termType></relation></term>  </Zthes>