Evaluation of Turkish seaweeds for antiprotozoal, antimycobacterial and cytotoxic activities

As part of our continuing research on seaweeds, crude MeOH extracts of two green, three brown and six red algae collected from Marmara, Black, Aegean and Mediterranean Seas were screened. Four parasitic protozoa, i.e. Plasmodium falciparum, Trypanosoma brucei rhodesiense, T. cruzi, Leishmania donovani and the tubercle bacillus Mycobacterium tuberculosis were used as test organisms for the in vitro assays. The selective toxicity of the extracts was also determined against mammalian L6 cells. All seaweed extracts were active against T. brucei rhodesiense; the Dasya pedicellata extract was the most potent (IC₅₀ value 0.37 µg/mL). The same extract also weakly inhibited the growth of T. cruzi (IC₅₀ 62.02 µg/mL). All seaweed extracts also showed leishmanicidal activity (IC₅₀ values 16.76–69.98 µg/mL). The majority of the extracts also exhibited antiplasmodial potential and the most potent extracts were those from D. pedicellata (IC₅₀ 0.38 µg/mL), Codium bursa (IC₅₀ 1.38 µg/mL) and Caulerpa rasemosa (IC₅₀ 3.12 µg/mL). One brown and two red algal extracts showed some weak activity against Mycobacterium tuberculosis (MIC values 125–256 µg/mL). Except for the extract of Dasya pedicellata, none of the extracts displayed any cytotoxicity. This is the second study investigating the antiprotozoal activities of Turkish marine algae and identifies Dasya pedicellata, an understudied algal species, as a candidate for further studies. Copyright © 2010 John Wiley & Sons, Ltd.     

Boron-containing organic pigments from a Jurassic red alga

Organic biomolecules that have retained their basic chemical structures over geological periods (molecular fossils) occur in a wide range of geological samples and provide valuable paleobiological, paleoenvironmental, and geochemical information not attainable from other sources. In rare cases, such compounds are even preserved with their specific functional groups and still occur within the organisms that produced them, providing direct information on the biochemical inventory of extinct organisms and their possible evolutionary relationships. Here we report the discovery of an exceptional group of boron-containing compounds, the borolithochromes, causing the distinct pink coloration of well-preserved specimens of the Jurassic red alga Solenopora jurassica. The borolithochromes are characterized as complicated spiroborates (boric acid esters) with two phenolic moieties as boron ligands, representing a unique class of fossil organic pigments. The chiroptical properties of the pigments unequivocally demonstrate a biogenic origin, at least of their ligands. However, although the borolithochromes originated from a fossil red alga, no analogy with hitherto known present-day red algal pigments was found. The occurrence of the borolithochromes or their possible diagenetic products in the fossil record may provide additional information on the classification and phylogeny of fossil calcareous algae.     

浒苔绿藻精抗实验性肝癌作用及其机理研究

目的探讨浒苔绿藻精抗实验性肝癌作用及其机理,为开发利用浒苔资源提供依据。方法通过接种肿瘤细胞（H22）建立小鼠实验性肝癌模型,给予不同剂量浒苔绿藻精进行干预,测定抑瘤率、脾脏指数和细胞因子白细胞介素-2（IL-2）、血管内皮生长因子（VEGF）及转化生长因子-β（TGF-β）以判断抑癌作用及作用机理。结果低、中、高剂量浒苔绿藻精均可抑制肿瘤生长（P〈0．01）,抑瘤率分别为13．9％、30．3％和27．3％;各剂量浒苔绿藻精均可显著提高小鼠的脾脏指数（P〈0．01）;高剂量浒苔绿藻精可显著提高IL-2水平（P〈0．01）;低、中、高剂量浒苔绿藻精均可显著降低TGF-β和VEGF水平（P〈0．01）。结论浒苔绿藻精对实验性肝癌模型小鼠的肿瘤生长具有抑制作用,其抑制机理可能与其影响机体IL-2、TGF-β和VEGF的水平有关。     

Copper and zinc tolerance of two tropical microalgae after copper acclimation

Current toxicity tests with microalgae are often criticized as being overly sensitive to metals because algae are cultured in metal-deficient media. If such bioassays overestimate copper toxicity in surface waters, the relevance of water quality guidelines derived from these tests is questionable. In this study, the effect of acclimation to copper at environmentally relevant concentrations, on the sensitivity of the marine diatom Nitzschia closterium and the freshwater green alga Chlorella sp. to copper and zinc was examined. N. closterium was acclimated in culture medium containing 5 or 25 microg Cu L(-1) for 200 days, while Chlorella sp. was acclimated in medium containing 2 microg Cu L(-1) for 100 days. Changes in algal growth rates and copper and zinc tolerance were monitored using standard growth inhibition toxicity tests in minimal medium over 72 h. Neither of the two acclimated N. closterium cultures had increased zinc or copper tolerance compared with that of the nonacclimated algae, nor were there any changes in control growth rates. Similarly, no changes in copper tolerance or control growth rates were observed for the acclimated Chlorella sp. culture. This was supported by measurements of intracellular and extracellular copper which confirmed that there were no differences in copper accumulation in either acclimated or nonacclimated algae. These results suggest that these algae grown in standard culture media are generally no more sensitive than algae grown in a metal-enriched medium. This supports the continued use of current laboratory bioassays with microalgae, as part of a suite of tests for assessing metal bioavailability, for use in ecological risk assessments and for providing data for the derivation of water quality guidelines.     

海藻中两种新化学成分的分离和结构鉴定

目的：研究中国南海褐藻Sargassum vachellianum和绿藻Ulva lactuca的化学成分。 方法：应用各种色谱技术进行分离纯化,用MS,IR,¹HNMR,¹³CNMR（DEPT）,HMQC和HMBC鉴定化合物。 结果：分离并鉴定了2个新化合物,化合物1 vachellin为11-甲基-Δ^1,5-3,7,10-三羰基-2,4,8,9-四氮-环十一二烯,化合物2 lactucasterol为胆甾-28-甲基-23,24-环丙烷-Δ⁵-4-酮。 结论：1和2为新化合物。     

海藻海蒿子褐藻糖胶的分离与组成分析

目的以海藻海蒿子为原料制备褐藻糖胶，并对不同的提取、分离方法进行比较，对多糖的组成和结构进行初步分析。方法海蒿子脱脂干粉分别经水提取和酸提取以获得粗多糖，粗多糖分别经乙醇沉淀法和CaCl2沉淀法进行纯化。选取多糖组分F4用Q—Sepharose Fast Flow和Sephadex G-200凝胶柱进行分级分离，高效凝胶渗透色谱法（HPGPC）鉴定纯度及相对分子质量，气相色谱分析多糖的中性单糖组成。结果F4经分级分离得到3个级分：P1、P2和P3。P1、P2和P3均为均一组分，相对分子质量分别为：494400、61500和167600；P1由岩藻糖、木糖、甘露糖、葡萄糖和半乳糖构成，摩尔百分比43．4：33．3：6．2：4．3：12．8；P2由岩藻糖、木糖、甘露糖和半乳糖构成，摩尔百分比44．4：15．1：23．8：16．7；P3由岩藻糖、木糖和半乳糖构成，摩尔百分比68．9：3．7：27．4。结论P1、P2和P3的单糖含量均以岩藻糖为主，但其他单糖组成有较大差别。     

雨水收集利用工艺及安全饮用的观察研究

该研究采用了环境卫生学、卫生工程学、卫生检测学、水生生物学、统计学和流行病学的方法进行研究．指出了雨水收集的重大意义和雨水收集的可行性工艺．包括采集方法、储水池建设、水质净化等。同时,对天然雨水水质按降雨时段进行了监测分析,并对所储存的雨水进行了卫生学指标、毒理学指标及水生生物学指标监测,并在一定范围内进行了腹泻搞人的流行病学调查。研究结果证实,雨水的收集利用在社会经济学、卫生经济学方面可产生巨大影响。有效的推广可创造可观的社会效益和经济效益。     

天然矿泉水淡水藻类污染检验方法研究

采用天然矿泉水淡水藻类的检验方法，在采自福建省各地区的２０２份样品中检出４２份阳性，共１５属藻类。这些藻在自然界淡水中常见。该方法独特之处是将浓缩培养基直接加入水样瓶中。然后，在培养过程中保持散射光照低于５０００Ｌｘ。瓶中样品的静置，有助于藻类从水处理造成的损伤中恢复。５～１０天后，绿色或蓝绿色的藻细胞将形成明显的斑点或沉淀。经镜检分类，检出了绿藻、蓝藻等１５个属。比较了５种培养基，以改良克诺普液使用效果最好。此培养基容易配制和应用，藻类生长快，观察方便。     

黄河水源水浮游藻类及藻类毒素污染状况动态研究

目的 :探讨黄河水源水浮游藻类和藻毒素污染状况及影响因素。方法 :于 1998年 5～ 12月在河南省S市、Z市、P市水源水设采样点 ,对水源水浮游藻类、藻类毒素污染情况及总氮、总磷、COD等指标进行了连续检测。结果 :河南省黄河水源水总氮检出范围为 2 5 7～ 6 .79mg/L ,总磷的检出范围为 0 0 1～ 0 .32mg/L ,蓝藻和绿藻为浮游藻类的优势种群。MC的阳性率 ( >2 0ng/L)为 82 6 1% ,最高达到 95 7 9ng/L。结论 :按照Carlson提出的富营养化指数TSI(TP)判定标准 ,结合TN、TP、COD及藻类密度等指标 ,认为河南省境内黄河水源水已呈现富营养化特征。磷是黄河水源水浮游藻类生长的主要限制因子 ,控制黄河水源水富营养化应以控制磷为主。     

Mineral and trace element concentrations in seaweeds from the sub-Antarctic ecoregion of Magallanes (Chile)

The P, Na, K, Ca, Mg, Fe, Cu, Zn and Mn concentrations were determined in seventy-three samples of seaweeds belonging to different genera (classified as brown, red and green seaweeds), which were collected from three zones in the sub-Antarctic ecoregion of Magallanes (Chile). There were clear differences in the concentrations between the considered genera. Brown seaweed had the highest mean K (31.4 g/kg) and Ca (10.3 g/kg) concentrations compared with red (14.1 g/kg for K and 3.11 g/kg for Ca) and green (13.9 g/kg for K and 7.58 g/kg for Ca) seaweed, and green seaweed had the highest mean Mg (15.0 g/kg), Fe (1260 mg/kg) and Cu (7.46 mg/kg) concentrations. The consumption of a serving (8 g) from of the three groups of brown, red and green seaweed is a good source of Fe, Mg and Mn (>25% of the Dietary Recommended Intake). Significant differences were observed in the mean concentrations of all the minerals and trace elements, except for Fe, Cu and Mn, between the three collection zones. Factor and discriminant analysis were used to differentiate the type of seaweed and sampling zone. Besides which, good classifications were obtained according to the type of seaweed using discriminant analysis.