Chitosan (300.0 kDa) was enzymatically degraded to obtain six degraded chitosans with molecular weights (MWs) of 156.0, 72.1, 29.2, 7.1, 3.3, and 2.2 kDa. The antioxidant and antimutagenic properties of all seven chitosan samples were evaluated in vitro. The antioxidant scavenging activities of chitosans on hydrogen peroxide and 2, 2-diphenyl-1-picryl hydrazyl radical, and on chelating ferrous ion were significantly increased with chitosan’s decreasing MW, with 2.2-kDa chitosan have the highest impact. All seven chitosan samples exhibited strong anitmutagenic effects against direct (4- nitroquinoline 1-oxide) and indirect (benzo[α]pyrene) mutagens in the presence of rat liver enzyme S9 mix in Salmonella typhimurium TA 98 and TA 100. The effect of MW on antimutagenicity was similar to that on antioxidant activity. The underlying mechanism for chitosan antimutagenicity proved to be its desmutagenic effect on mutagens.

 酶降解壳聚糖（300.0 kDa），以获得六种降解的壳聚糖，分子量（MWs）为156.0、72.1、29.2、7.1、3.3和2.2  kDa。在体外评估了所有七个壳聚糖样品的抗氧化剂和抗诱变特性。随着壳聚糖分子量的降低，壳聚糖对过氧化氢，2，2-二苯基-1-吡咯酰肼基和螯合亚铁离子的抗氧化清除活性显着增加，其中2.2kDa壳聚糖的影响最大。在鼠伤寒沙门氏菌中存在大鼠肝酶S9混合物的情况下，所有七个壳聚糖样品均表现出对直接（4-硝基喹啉1-氧化物）和间接（苯并[α] py）诱变剂的强力诱变作用。TA 98和TA100。MW对抗突变性的影响类似于对抗氧化活性的影响。壳聚糖抗诱变的潜在机制被证明是其对诱变剂的去诱变作用。