Chemical and physical characterization of calcified red algal deposits known as maërl

Maërl, comprised of shallow, subtidal deposits of calcareous red algae belonging to the family Corallinaceae, is used in agriculture, primarily to increase soil pH. Its use has been strongly criticised because of its high price compared to limestone. The chemical and physical characteristics of maërl and limestone are compared to determine whether these indicate if any benefit is to be gained with the use of the former. Analysis by inductively coupled plasma emission spectrophotometry shows that the proportion of magnesium in maërl is about ten times higher than that in the limestone samples tested. The levels of iron, boron and especially strontium are noticeably higher in the calcified seaweed than in the limestone, although the manganese contents are lower. Scanning electron microscopy shows that the surface characteristics of maërl and limestone are similar but, in section, maërl is considerably more porous because of its cellular structure. Atomic force microscopy revealed minor differences in fine structure between the two. The differences between maërl and limestone would not appear to compensate for the considerably higher costs involved with the utilization of the former material.     

THE ALKALOIDAL CONSTITUENTS OF CULTIVATED CHUAN-WU OF YUNNAN

Chuan Wu (Aconitum carmichaeli Debx.) is a famous chillese drug and is also an important original materials of thc famous Fuzi. The plant was much investigated by both chinese and japanese scientists. In this communication, we have investigated the plant which was introduced by a fine variety from Sichuan and cultivated at Dali prefecture of Yunnan. To bc very intcresting we found that this plant not only changes in quantity of alkaloidal constituents but changes in quality as well in making comparison with Chuan wu cultivated at Shanxi. We also isolated neolinc, songorine and a new compound fuziline from this plant except mesaconitine, hypaconitine, and aconitine reported before.     

椿根皮的化学成分及抑菌活性研究

为探寻椿根皮抑菌的物质基础，该研究采用硅胶、Sephadex LH-20等方法对椿根皮甲醇提取物进行分离和纯化，通过理化性质和波谱数据分析单体化合物的结构，并以卡那霉素为对照组采用流式细胞法测试化合物的抑菌活性。结果表明：从椿根皮中得到22个化合物，分别鉴定为pleuchiol (1)、withastramonolide (2)、7-ketositosterol (3)、白桦酯醇(4)、桦木酸甲酯(5)、1, 2, 4-trimethoxybenzene (6)、顺丁烯二酸二甲酯(7)、sonderianol (8)、dibutyl phthalate (9)、pinoresinol (10)、对羟基苯甲酸乙酯(11)、avenalumic acid methyl ester (12)、5,3′-dihydroxy-3,7,4′-trimethoxy-flavone (13)、spathulenol (14)、2-甲基-5-丙基酮-7-羟基色原酮(15)、 7,4′-dihydroxyflavone (16)、annphenone (17)、3-羟基-4-甲氧基苯甲酸(18)、5,3′...