Linolenic acid - Linolenic acid

It is a straight-chain unsaturated fatty acid C ₁₈ H ₃₀ O ₂ with double bonds at the 9th, 12th, and 15th positions, and has a distribution very similar to that of linoleic acid. As a glyceride, it is the main component of many drying oils. It is found in large amounts in vegetable oils, especially linseed oil and perilla oil. It is not synthesized in animals, and is one of the essential fatty acids. It has also been called vitamin F along with linoleic acid.

[Takayoshi Wakagi]

α-Linolenic acid is an essential fatty acid, but has a specific physiological effect different from that of linoleic acid. Thromboxane, which does not have platelet aggregation ability, is produced from eicosapentaenoic acid, which is desaturated in the animal body, so thrombosis and myocardial infarction are less common among Eskimos (Inuit in Canada, etc.) who eat a lot of fish and marine animals rich in eicosapentaenoic acid. Docosahexaenoic acid, one of the desaturation products, is found in large amounts in the brain and retina, and plays a special function in the nervous system. Small amounts of α-linolenic acid are found in edible vegetable oils such as soybean oil and rapeseed oil, but it is easily oxidized.

[Michihiro Kanno]

"Microorganisms with unique functions and their applications," edited by the Bio-Polymer Research Group of the Society of Polymer Science (1989, Society Publication Center)" ▽ "Oil, this delicious yet worrying thing -- the shattered myth of linoleic acid, health methods for dealing with oil," written by Okuyama Harumi (1989, Rural Culture Association)" ▽ "The Story of Dangerous Foods," written by Mizoguchi Atsushi (1993, Shogakukan)" ▽ "Fatty acids and health, lifestyle, and the environment -- from DHA to royal jelly," written by Kaneya Kunimitsu (1997, Shokabo)" ▽ "Revive your cellular power," edited by the Immunology Research Group and supervised by Iijima Shigeko (1998, Toyo Publishing)" ▽ "Lipid nutrition and lipid peroxidation -- is lipid peroxidation in the body damaging or defensive?" edited by Okuyama Harumi and Kikukawa Kiyomi, supervised by the Japanese Society for Lipid Nutrition (1998, Society Center Kansai)" ▽ "Harumi Okuyama, 'Adult diseases (lifestyle-related diseases) that cannot be cured with medicine -- Regaining health with the nutritional revolution of fats and oils' (1999, Reimeishobo)" ▽ "Kenji Hara, 'Physiologically active substances -- Biochemistry and applications of conjugated linoleic acid' (2000, Saiwai Shobo)" ▽ "Michihiro Kanno, 'The appeal of 'Fats' -- Nutritional theory of fats and oils' (2000, Kodansha)" ▽ "Effective perilla dishes -- Oil, leaves, seeds, and the whole plant are the source of health' compiled by the Japan Perilla Association and cooked by Miyoko Murakami and Hisae Tabata (2001, Souminsha)"

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

二重結合を9・12・15位にもつ直鎖不飽和脂肪酸C₁₈H₃₀O₂で、リノール酸ときわめてよく似た分布を示し、グリセリドとして多くの乾性油の主成分をなす。植物油、とくにあまに油、エゴマ油に多く含まれる。動物体内では生合成されず、必須脂肪酸(ひっすしぼうさん)の一つで、リノール酸とともにビタミンFとよばれたこともある。

［若木高善］

　α(アルファ)-リノレン酸は必須脂肪酸であるが、リノール酸とは異なった特異的生理作用を有している。動物体内で不飽和化され生成するエイコサペンタエン酸から血小板凝集能を有さないトロンボキサンがつくられるので、エイコサペンタエン酸に富む魚や海獣を多食するエスキモー（カナダなどではイヌイット）では血栓(けっせん)症、心筋梗塞(こうそく)が少ない。不飽和化産物の一つであるドコサヘキサエン酸は、脳や網膜などに多く存在し、脳神経系で特別な機能を果たしている。α-リノレン酸は食用植物油では大豆油、菜種油に少量含まれるが、酸化されやすい。

［菅野道廣］

『高分子学会バイオ・高分子研究会編『特異な機能を有する微生物とその応用』（1989・学会出版センター）』▽『奥山治美著『油　このおいしくて不安なもの――くずれたリノール酸神話　油とつきあう健康法』（1989・農山漁村文化協会）』▽『溝口敦著『あぶない食品物語』（1993・小学館）』▽『彼谷邦光著『脂肪酸と健康・生活・環境――DHAからローヤルゼリーまで』（1997・裳華房）』▽『イムノロジー研究会編著、飯島茂子監修『よみがえれ、あなたの細胞力』（1998・東洋出版）』▽『日本脂質栄養学会監修、奥山治美・菊川清見編『脂質栄養と脂質過酸化――生体内脂質過酸化は傷害か防御か』（1998・学会センター関西）』▽『奥山治美著『薬でなおらない成人病（生活習慣病）――油脂（あぶら）の栄養革命で健康を取り戻す』（1999・黎明書房）』▽『原健次著『生理活性物質――共役リノール酸の生化学と応用』（2000・幸書房）』▽『菅野道廣著『「あぶら」は訴える――油脂栄養論』（2000・講談社）』▽『日本エゴマの会編、村上みよ子・田畑久恵料理制作『よく効くエゴマ料理――油も葉も種も丸ごと健康の素』（2001・創森社）』

出典　小学館　日本大百科全書(ニッポニカ)日本大百科全書(ニッポニカ)について　情報 | 凡例