IMPROVEMENT OF FISHY FLAVORS FROM SARDINE BY MICRO-ORGANISMS AND DEVELOPMENT OF LIPOXYGENASE-INHIBITORS OF MICROBIAL ORIGIN

本研究旨在促进高产鱼的有效利用和利用微生物开发新的食品加工技术。研究了干鲣鱼加工霉菌（Eurotium herbariorum）的作用：(1)在沙丁鱼肉末中添加Eurotium herbariorum，能特异性抑制丙醛和1-戊烯-3-醇的生成，显著延缓鱼腥味的产生。(2)从该菌株菌丝体中纯化出许多脂氧合酶（LOX）抑制剂。(3)用该菌株处理醛类，可在短时间内转化为阈值较高的相应醇类和羧酸类。(4)在有菌丝垫存在的情况下对加工过的沙丁鱼进行贮藏试验，沙丁鱼的嗅觉气味良好。该菌株对鱼腥味的显著改善可能是基于对沙丁鱼肉LOX活性的抑制和对挥发性成分（如醛）的分解。对分离LOX抑制剂的野生丝状霉菌进行筛选：(1)在麦芽培养基中培养，用吸氧法测定LOX活性。(2)土曲霉（Aspergiluus terreus）产生了新的抑制剂1,3-二氢-7-甲基-4,5,6-三羟基-异苯并呋喃(a)，对沙丁鱼肉LOX具有显著的抑制作用。(3)青霉产生三种物质，分别为曲酸、去甲基曲酸和新化合物2,3-二乙酰-4,5-二羟基-6-甲氧基苯。其lox抑制活性弱于A。

The purposes of this study was aimed to contibute the effective utilization of highly harvested fish and to develop new food procesing technique using microorganisms.1. The function of Eurotium herbariorum (dried Skipjack tuna-processing mold) was investigated :(1) The addition of the strain to sardine mince specifically inhibited the formation of propanal and 1-penten-3-ol, leading to a remarkable retardation of fishy flavor.(2) Many lipoxygenase (LOX) inhibitors were purified from mycerial mats of the strain.(3) On treatment of aldehydes with the strain, they were converted into the corresponding alcohols and carboxylic acids having higher threshold values in a short time.(4) When storage tests of processed sardine were done in the presence of the mycerial mats, sardine had have smelled good organoleptically.A significant improvement of fishy flavor by the strain was likely to be based on the inhibition of sardine flesh LOX activity and the decomposition of volatile compoenents lile aldehydes.2. Screening of wild filamentous molds for the isolation of LOX inhibitors was done :(1) The molds were grown in malt medium and the LOX activity was assayd by the oxygen absorption method.(2) Aspergiluus terreus produced a new inhibitor, 1,3-dihydro-7-methyl-4,5,6-trihydroxy-isobenzofuran (A), which can remarkably inhibit sardine flesh LOX.(3) Penicillium daleae afforded three kinds of substances, vulculic acid, demethylcurvulic acid, and 2,3-diacetyl-4,5-dihydroxy-6-methoxy-benzene, a new compound. Their LOX-inhibitory activity was weaker than that of A.