稀土-落叶松单宁配合物的合成及抗真菌活性研究

以稀土(Re~(3+))和落叶松单宁(LT)为原料,采用液相合成法合成了5种廉价的稀土-落叶松单宁(Re~(3+)-LT)配合物,并通过红外光谱、X射线光电子能谱、紫外光谱以及配位数测定确定了配合物的结构.采用牛津杯法、琼脂稀释法测定配合物对黑曲霉、红曲霉、白腐菌、毛霉4种真菌的抑制作用.在抑菌方面,5种配合物对上述4种真菌均具有较强的抑制作用,其抑菌活性大小顺序为Ce~(3+)-LTGd~(3+)-LTLa~(3+)-LTNd~(3+)-LTYb~(3+)-LT,其中Ce~(3+)-LT对4种真菌的最小抑菌浓度分别为:1.6、1.6、0.8和1.6 g·L~(-1);Yb~(3+)-LT对4种真菌的最小抑菌浓度分别为:3.2、1.6、3.2和3.2 g·L~(-1).在杀菌方面,Yb~(3+)-LT的杀菌活性最强,其对4种真菌的最小杀菌浓度分别为:6.4、3.2、3.2和6.4 g·L~(-1).此外,尽管Nd~(3+)-LT和Gd~(3+)-LT具有较强的抑菌活性,但对黑曲霉和毛霉的杀菌作用较弱.

Synthesis, Characterization, and Antifungal Activity of Rare Earth-Larch Tannin Complexes

Five new and cheap rare earth complexes with larch tannin(LT) have been prepared by the chelating reaction of rare earth (Re³⁺) with larch tannin according the liquid phase synthesis method, and these complexes were characterized with FT-IR, XPS, UV and coordination number determination method. The antifungal activity of Re³⁺-LT against Aspergillus niger, Monascus anka, Phanerochaete chrysosporium and Actinomucor elegans was evaluated in vitro by using the oxford cup and agar dilution assay. It was found that the Re³⁺-LT complexes are effective for these four fungi, and the antifungal activity was in the order of Ce³⁺-LT > Gd³⁺-LT > La³⁺-LT > Nd³⁺-LT > Yb³⁺-LT. The minimum inhibitory concentration of Ce³⁺-LT to these four fungi is 1.6 g·L^-1, 1.6 g·L^-1, 0.8 g·L^-1, and 1.6 g·L^-1, respectively, while the Yb³⁺-LT is 3.2 g·L^-1, 1.6 g·L^-1 3.2 g·L^-1, and 3.2 g·L^-1, respectively. In terms of fugicide, Yb³⁺-LT is the best one and the minimum fugicide concentration of Yb³⁺-LT to these four fungi is 6.4 g·L^-1, 3.2 g·L^-1, 3.2 g·L^-1, and 6.4 g·L^-1, respectively. In addition, the fugicide activity of Nd³⁺-LT and Gd³⁺-LT against Aspergillus niger and Actinomucor elegans is less powerful even they have good antifungal activity.