Research Of Radicals Scavenged Activities Of Chitosan

Free radical is an active atom or atomic group without sharing electrons. It reacts with othermolecules by oxidation-reduction reaction through electron transfer. Many diseases occur if thereare excessive radicals in organism. As a natural basic polysaccharides, chitosan has goodbiodegradity, non-toxicity, bio-consistency. And the molecular structure makes it scavengeradicals. So revealing the rule and the principle of scavenging radical by chitosan is important inthe field of health and prevention.We simulate radicals in vivo by Fenton system. And basing on the high resolution andnon-damage effect, using AFM, we can observe the whole surface texture and microstructure ofred blood cell, then the radicals scavenged activity of chitosan is proved through themeasurement of the average roughness and the order of microstructure. And utilizing fluorescentquenching fluorescence experiment, the scavenging activities of chitosan can be showedquantitatively.The result indicate that: (1) by rising the concentration of chitosan, a more effectivescavenging activity on radical can be obtained. (2) by reducing the molecular weight, a moreeffective scavenging activity on radical can be obtained. (3) after destroyed by free radical, thewhole surface texture of red cell gets a better degree of order. (4) chitosan has a betterscavenging effect on hydroxyl radical than superoxide radical.(5) through these experimentphenomenon, we guess that: the reacting locuses of chitosan and hydroxyl radical are thesecondary hydroxyl and amino group of chitoan; the reacting locus of chitosan and superoxideradical is the secondary hydroxyl of chitosan.