Studies on the Production and Improvement of Flavors of Fishes and Shells in Microalgae

在这项研究中，我们集中精力澄清挥发性硫化合物、特别是二甲基硫化合物、微藻和宏观藻中的生物合成和作用。在水生环境中出现的二甲基sulphide的主要来源是要成为酶分解或碱降解的二甲基-贝塔-丙二烯将二甲基sulphide和丙烯酸酯。dimethylsulphide producers are chlorophyta （such as Ulva and Enteromorpha）、rhodophyta （such as Polysiphonia）、haptopyta （such as Emiliania and hymenomonas）和dinophyta （such as Gymnodinium、Gyrodinium和Crypthecodinium）。This dimethylsulphide fills the role originally assigned to H2S ; that of transfering sulphur from the seas through the air to land surface， and is very likely the compound most responsible for the characteristic“odor of the sea”or“flavour of sea weeds”.我们established the growth condition of Crypthecodinium cohnii （dinoflagellate） to get high cell yield （12 g wet weight/L）.From the relationship between the stru ... More 甲硫氨酸、二甲基β-丙硫汀和二甲基硫醚的研究，使我们最近的研究清楚地表明了这一点，在C。Cohnii、甲基组和二甲基β-丙硫汀的硫醚从甲基组和甲基硫氨酸的硫醚和甲基硫氨酸的碳基组不合并。我们展示了C的crude提取物。Cohnii具有甲硫氨酸去氨酶活性，但没有甲硫氨酸去氨酶活性。观察与甲基硫氨酸转化为3-甲基硫丙基胺的hypothesis是一致的，而3-甲基硫丙基胺则是通过deamination、氧化和甲基化转化为dimethyl-beta-propiothetin的hypothesis是一致的，即二甲基-beta-propiothetin可能从2-methionine引起的，我们还发现了二甲基-beta-propiothetin的precursor，二甲基-propothetin，它极大地促进了金鱼、鲤鱼、crucian鲤鱼和Tilapia的咬人行为。Dimethyl-Beta-propiothetin不仅能够提供对鱼类的刺激行为的有效刺激，但也能够提供促进鱼类增长的能力。从Crypthecodinium Cohnii及其主要成分、二甲基-β-propiothin、明显和依赖地保护对抗HCI-乙醇-诱导的树脂中提取物。自从Indomethacin pretraetment减少了一些潜在的、内源性前列腺素可能在行动的机制中部分参与。Both the crude extract and dimethyl-beta-propiothetin significantly increased gastric secretion.The volatile components of Crypthecodinium cohnii were investigated to find its pleasant flavour compounds that could be associated with some edible seashore products。用玻璃珠加热新鲜的湿藻，增加了66个挥发性组件。第一次直接分散，大部分含有二甲基硫醚，接近99%。其他成分包括一些强甜碘化合物; 2-羟基-3-甲基1 - 2-环戊烯-l-one（cyclotene）、2，5-二甲基-4-羟基-3（2 H）-呋喃酮（呋喃醇）和3-羟基-2-甲基-4 H-吡烷-4-one（麦芽醇）。Less（低）

In this study, we concentrated to make clear the biosynthesis and role of volatile sulphur compound, especially dimethylsulphide, in microalgae and macroalgae. The major source of dimethylsulphide in the aquatic environment appears to be the enzymatic cleavage or alkaline degradation of dimethyl-beta-propio thetin into dimethylsulphide and acrylate. The dimethylsulphide producers are chlorophyta (such as Ulva and Enteromorpha), rhodophyta (such as Polysiphonia), haptopyta (such as Emiliania and hymenomonas) and dinophyta (such as Gymnodinium, Gyrodinium, and Crypthecodinium). This dimethylsulphide fills the role originally assigned to H2S ; that of transferring sulphur from the seas through the air to land surface, and is very likely the compound most responsible for the characteristic "odor of the sea" or "flavour of sea weeds".We established the growth condition of Crypthecodinium cohnii (dinoflagellate) to get high cell yield (12g wet weight/L).From the relationship between the stru … More ctures of methionine, dimethyl-beta-propiothetin and dimethyl-sulphide, our recent study make clear that, in C. Cohnii, the methyl group and the sulphur of dimethyl-beta-propiothetine are derived from the methyl group and the sulphur of methionine and that the carboxyl group of methionine is not incorporated. We showed the crude extracts of C. Cohnii had methionine decarboxylase activity and did not have methionine deaminase activity. The observation are consistent with the hypothesis that methionine is converted to 3-methylthiopropylamine by decarboxylation and that 3-methylthiopropylamine is converted to dimethyl-beta-propiothetin by deamination, oxidation and methylation, and that the carboxyl group of dimethyl-beta-propiothetine may arise from the 2-carbon of methionine.We also found that the precursor of dimethylsulphide, dimethyl-beta-propiothetin, greatly accelerates the biting behaviors of goldfish, carp, crucian carp and tilapia. Dimethyl-beta-propiothetin proved not only to be an effective stimulant for the striking behavior of fishes but also to be able to promote fish growth. A crude extract of Crypthecodinium cohnii and its main component, dimethyl-beta-propiothetin, significantly and dose dependently protected the gastric mucosa against HCI-ethanolーinduced lesions in rats. Since indomethacin pretraetment reduced the protective effect to some extent, endogenous prostaglandins might be partly involved in the mechanism of action. Both the crude extract and dimethyl-beta-propiothetin significantly increased gastric secretion.The volatile components of Crypthecodinium cohnii were investigated to find its pleasant flavour compounds that could be associated with some edible seashore products. Heating the fresh wet alga with glass beads gave 66 volatile components. The first intact distillate greatly contained dimethylsulphide nearly 99%. Other components included some strong sweet-odorus compounds ; 2ーhydroxy-3-methy1-2-cyclopenten-l-one (cyclotene), 2, 5-dimethyl-4-hydroxy-3 (2H) -furanone (furaneol), and 3-hydroxy-2-methyl-4H-pyran-4-one (maltol). Less