Sugiyanti Dina, Darmadji Purnama, Santoso Umar, Pranoto Yudi, Anwar Chairil, Anggrahini Sri
Pak J Biol Sci. 2018 Jan;21(9):441-447. doi: 10.3923/pjbs.2018.441.447.
Low molecular weight chitosan (LWCS) was interestingly used because of it's solubility and has good functional properties like antioxidant and antibacterial activity. This study aimed to evaluate antioxidant and antibacterial activity of chitosan and low molecular weight chitosan.
Low molecular weight chitosan was obtained by physical and chemical hydrolysis using steam explosion process with steam pressure at 6 bar, temperature at 160°C and concentration of phosphotungstic acid at 0.1% w/v. The antioxidant activity was confirmed by radical DPPH scavenging activity, chelating metal ion value, inhibitory lipid peroxidation and antibacterial activity was confirmed by diffusion methods.
LWCS had antioxidant activity higher than native chitosan on radical scavenging, chelating ion value and inhibition of lipid peroxidation. LWCS had higher inhibitory effect as antibacterial than native chitosan against tested bacteria, there were Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Streptococcus aureus and Bacillus subtilis.
It was concluded that LWCS had more powerful antioxidant and antibacterial activity than native chitosan.
低分子量壳聚糖（LWCS）因其溶解性而备受关注，且具有抗氧化和抗菌活性等良好的功能特性。本研究旨在评估壳聚糖和低分子量壳聚糖的抗氧化及抗菌活性。
采用蒸汽爆破法进行物理和化学水解制备低分子量壳聚糖，蒸汽压力为6巴，温度为160°C，磷钨酸浓度为0.1%（w/v）。通过自由基DPPH清除活性、螯合金属离子值、抑制脂质过氧化来确认抗氧化活性，通过扩散法确认抗菌活性。
在自由基清除、螯合离子值和抑制脂质过氧化方面，LWCS的抗氧化活性高于天然壳聚糖。在对受试细菌（大肠杆菌、铜绿假单胞菌、鼠伤寒沙门氏菌、金黄色葡萄球菌和枯草芽孢杆菌）的抗菌作用上，LWCS比天然壳聚糖具有更强的抑制效果。
得出结论，LWCS比天然壳聚糖具有更强的抗氧化和抗菌活性。
