壳聚糖衍生物金属配合物的制备及其抑菌、抗氧化活性研究

【作者】 刘松；

【导师】 李鹏程；

【作者基本信息】 中国科学院研究生院（海洋研究所） ， 海洋化学， 2004， 硕士

【摘要】 本论文制备了几种壳聚糖衍生物金属配合物，并对其抑菌及抗氧化活性进行了研究。 采用微波辐射制备了不同分子量的壳聚糖，探讨反应介质、氧化剂与壳聚糖配比、辐射功率和辐射时间对降解反应的影响。结果表明：选择不同的反应条件，微波辐射 1-6min 就可制备出相对分子量在 1-10 万之间不同分子量大小的壳聚糖，且反应产率高、重复性好。 在微波辐射下进行壳聚糖的羧甲基化反应，制备羧甲基壳聚糖。在此基础上，不同分子量的壳聚糖及羧甲基壳聚糖与金属盐溶液反应制备壳聚糖 Cu(Ⅱ)、Zn(Ⅱ)、Cr(Ⅲ)配合物和羧甲基壳聚糖 Cu(Ⅱ)、Zn(Ⅱ)配合物。对壳聚糖 Cr(Ⅲ)配合物的制备工艺进行了详细探讨。采用紫外、红外等分析手段对配位基团和配位方式进行了分析。 首次采用微波辐射技术对壳聚糖及其铜、锌配合物进行硫酸酯化修饰，合成壳聚糖硫酸酯 Cu(Ⅱ)、Zn(Ⅱ)配合物，产物具有良好的水溶性、硫酸基含量在 30%以上。采用红外、核磁共振等分析手段对配合物的结构进行了分析确定。 以 NADH-PMS-NBT 体系产生超氧阴离子自由基（O2 ）和 EDTANa2 Fe(Ⅱ)-H2O2 ·- ·体系产生羟自由基（·OH）来研究配合物对氧自由基的清除活性，从而考察其抗氧化能力。结果显示配合物对超氧阴离子自由基和羟自由基均具有明显的清除作用，并成量效关系。其中 3 种铜(Ⅱ)配合物、低分子量壳聚糖硫酸酯 Zn(Ⅱ)配合物对超氧阴离子自由基具有显著的清除活性，在极低浓度下（25μg/mL）的清除率高达 89.18-94.18%；壳聚糖锌(Ⅱ)配合物、羧甲基壳聚糖锌(Ⅱ)配合物对羟自由基的清除能力最强，在 1.6mg/mL 样品浓度下的清除率分别为 72.78%、73.98%。对配合物的抗氧化机理进行了初步探讨。 采用平板抑菌法测定了配合物对四种常见农作物病原菌的抑制效果。结果发现，不同分子量的壳聚糖 Cu(Ⅱ)、Zn(Ⅱ)配合物、羧甲基壳聚糖 Cu(Ⅱ)配合物及低分子量的壳聚糖硫酸酯 Cu(Ⅱ)配合物对苹果腐烂病菌有明显的抑制作用；低分子量壳聚糖 Cu(Ⅱ)配合物对苹果轮纹病菌有一定的抑制效果；所有配合物在试验浓度范围内，对棉花枯萎病菌和蕃茄早疫病菌均无抑制作用。探讨了 i<WP=6>配合物的结构、金属含量、分子量大小等因素对抑菌性能的影响。通过本文的研究表明壳聚糖及其衍生物与 Cu(Ⅱ)、Zn(Ⅱ)形成的配合物具有明显的抗氧化活性，对某些农作物病原菌（苹果腐烂菌）也具有明显的抑制效果。证明金属 Cu(Ⅱ)、Zn(Ⅱ)离子对壳聚糖及其衍生物的生物活性起到一定的促进作用，形成配合物后具有加合性和增效性。为今后进一步研究和应用奠定了基础。更多还原

【Abstract】 Some kinds of complexes of Chitosan derivatives with the metal were prepared,and their antibacterial activity and antioxidant activity were also studied in this paper. Chitosans with low molecular weight were prepared by using microwaveirradiation. The effects of various factors:reaction solution,oxidant/Chitosan ratio,microwave irradiation power and time on the degradation reaction were investigatedin this paper. The results showed that chitosans with 10-100 thousand molecularweight were prepared in 1-6 minutes by microwave irradiation under the differentreaction conditions. At the same time the yield was higher and repetition was well. The carboxymethyl Chitosan has been prepared under microwave irradiationcondition. Furthermore, the complexes of Chitosan with copper( Ⅱ ),zinc( Ⅱ ),chromium(Ⅲ) and the complexes of carboxymethyl Chitosan with copper(Ⅱ),zinc( Ⅱ ) have been synthesized by metal solution reacted with Chitosan orcarboxymethyl Chitosan. Preparing conditions of the complexes chitosan withchromium(Ⅲ) were investigated. The configurations of them were analyzed by UVand IR spectra. For the first time, chitosan and its complexes with copper(Ⅱ) or zinc(Ⅱ) weresulfation modified by using microwave irradiation. The metal complexes withsulfation chitosan have been synthesized. All were soluble in water and vitriol groupcontent was over 30%. The structures of them are characterized by IR and NMRspectra. The free radical scavenging effects on superoxide anion radical byNADH-PMS-NBT system and hydroxyl radical by EDTANa2·Fe(Ⅱ)-H2O2 system ofthese complexes were studied. The antioxidant ability of them was analyzed from it.The results demonstrated that all of the complexes showed excellent ability forscavenging the superoxide anion radical and hydroxyl radical. Three kinds ofcopper(Ⅱ) complexes and the low-molecular-weight complexes of sulfation chitosanwith zinc(Ⅱ) displayed the highest scavenging effects on the superoxide anion radical.When mass concentration of samples was 25μg/mL,the scavenging activity were89.18-94.18%. The complexes chtiosan with zinc( Ⅱ )and the complexes ofcarboxymethyl Chitosan with zinc(Ⅱ) displayed the highest scavenging effects on thehydroxyl radical. When mass concentration of samples was 1.6mg/mL,the scavengingactivity were 72.78%, 73.98%.The antioxidation mechanism of these samples werealso investigated. The inhibition effects of the complexes on the four kinds of the growth of croppathogenic fungi were tested on PDA medium.The results showed that the differentmolecular weight of the complexes of Chitosan with copper(Ⅱ)or zinc(Ⅱ), thecomplexes of carboxymethyl Chitosan with copper(Ⅱ) and the low-molecular-weight iii<WP=8>complexes of sulfation chitosan with copper(Ⅱ) had excellent inhibition on Valsamali. The low-molecular-weight complexes of chitosan with copper( Ⅱ ) hadinhibition on Botyosphaeria berengeriana. All of samples had no inhibition onFusarinm oxysporium.f.sp.vasinfectum and Alternaria Solani under this testconditions. The effects of the structures, the metal content and molecular weight ofthe complexes on inhibition activity wree investigated. The results showed that the complexes of chitosan and its with copper(Ⅱ),zinc(Ⅱ) had excellent ability for scavenging the superoxide anion radical andhydroxyl radical and had also inhibition effects on the growth of crop pathogenicfungi(Valsa mali). It was proved that the metal ion advanced biology activity of thesecomplexes, the complexes added their activities. It was estabished the foundations forstudy and apply for the future.更多还原