Mechanisms underlying bioactivity of edible seaweed/algae constituents

拟议的研究旨在鉴定和表征从加拿大东部（Grand Manan， NB； NS， PEI）和西部（Bamfield, bc）海岸收获的可食用海藻的独特成分的保护性抗氧化和其他生物活性。这些海藻成分可以潜在地抑制加工食品中的脂质氧化，以提高其安全性和稳定性；并在减少乳腺癌或结肠癌中与饮食相关的慢性疾病风险因素方面发挥作用。我们已经发表了食用海藻的提取物的抗氧化活性的数据，包括dulse （P. palmata）和各种海带（Laminaria, Macrocystis, Nereocystis sp.）。我们还报道了杜仲提取物的一种抗氧化活性与生长过程中的紫外线暴露水平有关。与细胞培养的海带提取物相比，豆瓣提取物表现出更强的抗增殖活性。最近，我们确定了红藻特有的真菌孢素样氨基酸（MAAs），并证明了在生长过程中暴露于不同量的紫外线照射下的样品的MAAs的差异。在本提案中，我们计划：a)使用色谱法确认身份，并从杜斯、爱尔兰苔藓和假爱尔兰苔藓中分离出“克”数量的MAAs，用于抗氧化和细胞培养研究，因为这些化合物无法在商业上获得；b)使用新的和已建立的抗氧化试验来确定粗红藻提取物和纯化MAAs的有效性；c)研究粗红藻提取物和纯化MAAs对结肠癌和乳腺癌细胞系的抗增殖活性及其对细胞酶系统（如氧化途径）的影响；d)确定动物模型中膳食MAAs是否被吸收并进入循环；e)研究豆类饮食对大鼠乳腺癌的影响，并确定这些影响是否与红藻MAAs或纤维等其他成分有关。这些研究将培养3名硕士，1名博士生和一名功能食品研究领先领域的技术人员，并将其应用于食品行业，特别是海事行业，以及降低慢性病风险。

The proposed research seeks to identify and characterize the protective antioxidant and other biological activities of unique components from edible seaweeds harvested from the east (Grand Manan, NB; NS, PEI)  and west (Bamfield, B.C.) coasts of Canada. These seaweed components can potentially inhibit lipid oxidation in processed foods to increase their safety and stability; and play a role in reducing diet-related chronic disease risk factors in breast or colon cancer studied using animal models. We have published data on the antioxidant activities of extracts from edible seaweeds including dulse (P. palmata) and various kelps (Laminaria, Macrocystis, Nereocystis sp.). We also reported that one of the antioxidant activities of dulse extracts was related to the level of UV- exposure during growth. Dulse extracts exhibited greater antiproliferative activity compared to those of the kelps in cell culture. Recently, we identified mycosporine-like amino acids (MAAs) unique to red algae, in dulse and demonstrated differences in the MAAs of samples exposed to varying amounts of UV-irradiation during growth. In this proposal, we plan to: a) use chromatography to confirm the identity and isolate 'gram'  quantities of MAAs from dulse, Irish Moss and False Irish Moss to use in antioxidant and cell culture studies since these compounds are not available commercially; b) use new and established antioxidant assays to determine the effectiveness of crude red algal extracts and purified MAAs; c) study the antiproliferative activity of crude red algal extracts and purified MAAs against colon and breast cancer cell lines and their influence on cellular enzyme systems such as the oxidation pathways; d) determine whether dietary MAAs are absorbed and enter the circulation in animal models; e)study the effects of dulse diets on breast cancer in rats and determine if these effects are related to red algal MAAs, or other components such as the fibre. These studies will train 3 MSc, 1 PhD students & a technician in a leading area of Functional Food research with application to the food industry, particularly the Maritimes, and chronic disease risk reduction.