A methoxylated fatty acid isolated from the brown seaweed Ishige okamurae inhibits bacterial phospholipase A2

A methoxylated fatty acid that inhibits phospholipase A(2) (PLA(2); EC 3.1.1.4) was purified from the brown seaweed Ishige okamurae. Approximately 8.1 mg of the inhibitory compound, 7-methoxy-9-methylhexadeca-4,8-dienoic acid, was isolated from 1 kg of I. okamurae powder. Recombinant PLA(2) derived from the pathogenic bacterium Vibrio mimicus was used as the target enzyme. The methoxylated fatty acid compound competitively inhibited PLA(2) with a Ki value of 3.9 microg/mL. The concentrations required for 50% inhibition of PLA(2), oedema and erythema were 1.0 microg/mL, 3.6 mg/mL and 4.6 mg/mL, respectively. The compound strongly inhibited PLA(2) activity in vitro and had potent antiinflammatory activity in vivo.     

褐藻铁钉菜化学成分的研究(Ⅱ)

采用稻瘟霉模型生物活性追踪方法，应用多种层析手段，从采自浙江南麂岛的褐藻铁钉菜(Ishigeokamurai)中分离得到6个化合物，应用多种波谱技术，分别确定为：3β，28ξ-二羟基-24-乙基-5，23Z-胆甾二烯(J)，13^2S-羟基脱铁叶绿素a(Ⅱ)。脱镁叶绿素a(Ⅲ)，1-O-二十六烷酰基甘油酯(Ⅳ)，1-O-十六烷酰基甘油酯(V)和l-O-(8Z-十四碳烯酰基)甘油酯(Ⅵ)。6个化合物均为首次从该种海藻中得到，Ⅰ和Ⅵ分别为新化舍物和新天然产物，Ⅰ～Ⅲ具有诱导稻瘟霉菌丝变形活性和肿瘤细胞毒性。     

东亚绢藓化学成分研究

目的 研究东亚绢藓Entodon okamurae的化学成分。方法 用硅胶柱色谱，凝胶柱色谱及制备TLC对东亚绢藓的乙醇提取物进行分离纯化，通过^1HNMR,^13CNMR,DEPT,IR,MS等波谱学方法对其分离产物进行结构鉴定。结果 分离得到了9个化合物，分别确定为：大黄酚（chrysophamol,Ⅰ），大黄素甲醚（physcion,Ⅱ），二十九烷-10-醇（nonacosamn-10-ol,Ⅲ），dryocrassol(Ⅳ），邻苯二甲酸异丁酯（phthalic acid isodibutyl ester,Ⅴ），正十六烷醇（n-hexadecanol,Ⅵ），莪术醇（curcumol,Ⅶ），β-谷甾醇（β-sitosterol,Ⅷ）和β-胡萝卜苷（β-daucsosterol,Ⅺ）。结论 上述化合物均系首次从该属植物中得到，除β-谷甾醇和β-胡萝卜苷外，其他化合物均为第一次从藓纲植物中分离得到。     

利用稻瘟霉分生孢子筛选有生物活性的海洋生物

目的:筛选有生物活性的海洋生物并研究其活性成分.方法:采用稻瘟霉模型筛选海洋生物提取物的活性,利用多种层析手段和波谱技术对活性提取物跟踪分离并鉴定其成分.结果:实验发现20种海洋生物醇提物和5种水提物对稻瘟霉显示生物活性,从叶托马尾藻、铁钉菜和蓝斑背肛海兔中分离鉴定了56个化合物,其中28个对稻瘟霉显示活性且对不同肿瘤细胞株显示不同强度的细胞毒性,8个化合物对裴氏着色真菌具抑制作用.结论:利用稻瘟霉模型对海洋生物的活性成分进行跟踪分离是可行的.     

褐藻铁钉菜中的甾醇成分

采用稻瘟霉模型生物活性追踪方法，应用多种层折手段，从采自浙江南鹿岛的褐藻铁钉菜（Ishige okamurai)中分离得到39个化合物。本文报道其中5个甾醇类化合物（5α，8α－过氧麦角甾－6，22－二烯－3β－醇，马尾藻甾醇，岩藻甾醇，β－谷甾醇，胡萝卜苷）的分离和结构鉴定。     

铁钉菜化学成分的研究(3)

目的 :对铁钉菜进行化学成分研究。方法 :采用稻瘟霉模型生物活性追踪方法 ,应用多种色谱技术进行分离 ,根据理化性质和波谱数据鉴定其结构。结果 :分离并鉴定了7个化合物 :(2S)-1-O-十六碳酰基-2-O-(11Z-十八碳烯酰基 )-3-O-β-D-吡喃半乳糖基甘油 (I) ,(2S)-1-O-十六碳酰基-2-O-十四碳酰基-3-O-(6 '-硫代-α-D-脱氧吡喃葡萄糖基 )甘油 (Ⅱ) ,(2S)-1-O-十六碳酰基-2-O-十六碳酰基-3-O-(6 '-硫代 -α-D-脱氧吡喃葡萄糖基 )甘油 (Ⅲ) ,(2S)-1-O-十六碳酰基-2-O-(11Z-十八碳烯酰基 )-3-O-(6 '-硫代-α-D-脱氧吡喃葡萄糖基 )甘油 (Ⅳ ) ,硬脂酸 (V) ,肉豆蔻酸甲酯 (Ⅵ)和棕榈酸 (Ⅶ)。结论 :I～Ⅵ系首次从铁钉菜中得到 ;I,Ⅱ ,Ⅳ为新天然产物 ,I～Ⅳ具有诱导稻瘟霉菌丝变形活性和较弱的肿瘤细胞毒活性。     

Diphlorethohydroxycarmalol, isolated from the brown algae Ishige okamurae, protects against radiation-induced cell damage in mice

The aim of this study was to evaluate the radioprotective effects of diphlorethohydroxycarmalol (DPHC), isolated from the brown algae Ishige okamurae, in mice subjected to gamma irradiation.DPHC significantly decreased the level of radiation-induced intracellular reactive oxygen species in cultured Chinese hamster lung fibroblast (V79-4) cells (p < 0.05), enhanced cell viability that decreased after exposure to γ-rays, and reduced radiation-induced apoptosis in the V79-4 cells.Pretreatment with DPHC (100 mg/kg) in mice prior to irradiation significantly protected the intestinal crypt cells in the jejunum (p < 0.01) and maintained villi height (p < 0.01), compared with those of the vehicle-treated irradiated group. Mice pretreated with DPHC also exhibited dose-dependent increases in the bone marrow cell viability. The dose-reduction factor for gamma irradiation in the DPHC-pretreated mice was 2.05 at 3.5 days after irradiation.These results suggest that DHPC plays a role in protecting cells from irradiation-induced apoptosis, through the scavenging of reactive oxygen species in vitro, and that DPHC significantly protected intestinal progenitor cells and bone marrows cells that were decreased by gamma irradiation in vivo.     

Ishige okamurae ameliorates hyperglycemia and insulin resistance in C57BL/KsJ-db/db mice

We investigated the effect of Ishige okamurae extract on blood glucose level and insulin resistance in C57BL/-KsJ-db/db mice. We administered a standard AIN-93G diet with or without IOE to the animals for 6 weeks. After 6 weeks, blood glucose level was improved and blood glycosylated hemoglobin levels were lowered in sample group mice as compared to those in the diabetic control group mice. Hyperinsulinemia was reduced in the I. okamurae extract group mice with type 2 diabetes. With regard to hepatic glucose metabolic enzyme activities, glucokinase activity was enhanced in the IOE group mice, while glucose-6-phosphatase and phosphoenolpyruvate carboxykinase activities in the IOE group mice were significantly lowered than those in the diabetic control group mice. In addition, the hepatic glycogen content was elevated in the IOE group as compared to that in the diabetic control group. The homeostatic index of insulin resistance was lower in the I. okamurae extract group mice than in the diabetic control group mice. These results suggest that a dietary supplement of I. okamurae extract lowers the blood glucose level by altering the hepatic glucose metabolic enzyme activities and improves insulin resistance.