黄龙嗜冷细菌两种胞外单糖对碳酸钙矿化影响

为了探究黄龙水体中嗜冷细菌的胞外代谢产物对钙华沉积速率及沉积产物的影响,本文从黄龙钙华水体中分离到优势土著嗜冷细菌,并以其标志性胞外代谢产物D-葡萄糖和D-核糖作为研究对象,研究了两种单糖组分在低温环境下对钙华沉积的影响,并通过X射线衍射(XRD)、扫描电子显微镜(SEM)、红外吸收光谱(FT-IR)等分析手段对碳酸钙晶型、形貌以及结构组成进行了表征。实验表明:D-葡萄糖在低温条件下能促进方解石型碳酸钙的沉积,并加快沉积速率。低浓度下(20 mg/L和40 mg/L)的沉积产物均为方解石型碳酸钙并对其形貌有一定的影响;高浓度下(80 mg/L和160 mg/L)能诱导少量的文石型碳酸钙的合成。D-核糖在低温条件下能促进碳酸钙的沉积,加快沉积速率。与D-葡萄糖不同,D-核糖仅能合成方解石型碳酸钙,但对方解石晶面的生长表现为抑制作用,且随浓度增大抑制作用益明显。此结果可为黄龙钙华生物成因的探究提供一定的理论研究基础。

The effects of two kinds of extracellular monosaccharides on the mineralization of calcium carbonate

In order to explore the effect of extracellular metabolites of psychrophilic bacteria in Huanglong water on the travertine deposition rate and deposition products, the authors started with the Huanglong travertine water isolated advantage of indigenous psychrophilic bacteria, and took its landmark extracellular metabolites D-glucose and D-ribose as the object of study. The effects of two kinds of monosaccharide components on the deposition of travertine were investigated and, by means of X-ray diffraction (XRD), scanning electron microscope (SEM), infrared absorption spectroscopy (FT-IR) analysis, the types of calcium carbonate crystal morphology and structural composition were characterized. The results are as follows:D-glucose could promote the deposition of calcite-type calcium carbonate at low temperature and accelerate the deposition rate. The deposition products of low concentration (20 mg/L, 40 mg/L) were all calcite calcium carbonate and had a certain effect on their morphology; high concentrations (80 mg/L and 160 mg/L) could induce the synthesis of small amounts of aragonite calcium carbonate. D-ribose could promote the deposition of calcium carbonate at low temperature and accelerate the deposition rate. Unlike D-glucose, D-ribose could only synthesize calcite-type calcium carbonate, but it was an inhibitory effect on the growth of calcite crystal face, and its inhibitory effect was obvious with increasing concentration. The results can provide a theoretical basis for the exploration of Huanglong travertine.