|
ChemicalBook Optimization Suppliers |
|
| 融点 | 190-194 °C (dec.) | | 比旋光度 | 20.5 º (c=10,H2O) | | 沸点 | 227.71°C (rough estimate) | | 比重(密度) | 1,65 g/cm3 | | FEMA | 2109 | ASCORBIC ACID | | 屈折率 | 21 ° (C=10, H2O) | | 貯蔵温度 | Store at +5°C to +30°C. | | 溶解性 | H2O: 50 mg/mL at 20 °C, clear, nearly colorless | | 外見 | powder | | 酸解離定数(Pka) | 4.04, 11.7(at 25℃) | | 色 | white to slightly yellow | | PH | 3.59(1 mM solution);3.04(10 mM solution);2.53(100 mM solution); | | 臭い (Odor) | Odorless | | 酸塩基指示薬変色域(pH) | 1 - 2.5 | | 光学活性 (optical activity) | [α]25/D 19.0 to 23.0°, c = 10% in H2O | | においのタイプ | green | | 水溶解度 | 333 g/L (20 ºC) | | Merck | 14,830 | | BRN | 84272 | | BCS Class | 1 | | 安定性： | Stable. May be weakly light or air sensitive. Incompatible with oxidizing agents, alkalies, iron, copper. | | InChIKey | CIWBSHSKHKDKBQ-JLAZNSOCSA-N | | LogP | -1.85 | | CAS データベース | 50-81-7(CAS DataBase Reference) | | NISTの化学物質情報 | L-Ascorbic acid(50-81-7) | | EPAの化学物質情報 | Ascorbic acid (50-81-7) |
| | L-アスコルビン酸 Usage And Synthesis |
| 外観 | 無色澄明の液体 | | 定義 | 本品は、ビタミンCであり、次の化学式で表される。 | | 歴史 | アスコルビン酸は抗壊血病性ビタミンとよばれていた。壊血病は13世紀の十字軍時代にすでに記載され、1535年にはカルチエがカナダのセント・ローレンス川の探検中に、彼の部下たちの「何人かは力がなくなり、立つことができなくなり、他のものは体中の皮膚が内出血し紫の斑点(はんてん)でまだらになった。彼らの口は悪臭を放ち、歯肉は腐り、歯はほとんど抜け落ちた」と記載されている。壊血病の予防法は、1753年にスコットランドの医師リンドJames Lind（1716―1794）によって「検証はできていないが、青菜か新鮮な野菜、熟した果物が壊血病の最上の治療薬となるので、これらが同病に対するもっとも有効な予防薬であることは明らかである」と提示された。有効物質の抽出は、1927年セント・ジェルジーがウシの副腎(ふくじん)皮質から取り出した結晶（ヘキスロン酸）で、これがビタミンCそのものであり、抗壊血病性であるところからアスコルビン酸と命名された。このビタミンはヒトその他の霊長類やモルモットの食餌(しょくじ)には欠かせないが、ほかの動物はこれを体内で合成できる。 | | 解説 | ビタミンCのこと。抗壊血病効果をもつ酸（anti-scorbutic acid）にその名の由来がある。AsAと略記される。分子式C6H8O6、分子量176.13、融点190～192℃、還元力はC-2位および3位のエンジオール基-C(OH)=C(OH)-に由来する。白色またはわずかに黄色味を帯びた結晶で酸味があり、光によって徐々に着色する。乾燥状態では安定であるが、水溶液ではかなり不安定である。結合組織の主要なタンパク質であるコラーゲンタンパクの三重螺旋(らせん)構造は4-ヒドロキシプロリンによって構成されている。このアミノ酸はプロリンからプロリン水酸化酵素の触媒でつくられる。この酵素が活性化するときにアスコルビン酸が特異的な抗酸化剤として働く。生体内でアスコルビン酸のない条件下で合成されたコラーゲンのプロリンはヒドロキシル化されにくく、このようなコラーゲン繊維が壊血病でみられる皮膚の変化や血管のもろさの一因となる。アスコルビン酸は、鉄イオンの運搬体であるフェリチンから鉄イオンを遊離し、組織が鉄イオンを利用するのを助ける。そして、その欠乏によって組織内の遊離鉄イオンが減少するので、骨髄細胞のヘモグロビン合成が低下して貧血をおこすと考えられる。アスコルビン酸欠乏症では貧血のほか、骨の発育障害や創傷治癒の遅れなどもみられるが、これらはコラーゲンとコンドロイチン硫酸の合成障害によるものである。アスコルビン酸は腸から容易に吸収され、代謝活動の盛んな臓器に多く含まれる。血液中の濃度が1～1.5ミリグラム％（mg/dl）以上になると尿中に排泄(はいせつ)される。1日10ミリグラムが最低必要量で、イギリスでは20ミリグラム、アメリカでは70ミリグラムを摂取基準としている。なお、動物の場合は大量に与えても毒性は低い。 キュウリやカボチャなどの野菜にはアスコルビン酸を酸化するアスコルビン酸オキシダーゼがあるので、食品を短時間煮沸するとこの酵素が不活性となり、食品中のアスコルビン酸の保存がよくなる。［有馬暉勝·有馬太郎·竹内多美代］ | | 用途 | ビタミン C 化合物です。コラー
ゲン生合成に作用を示します。 | | 健康への影響 | 抗壊血病因子として発見された，ビタミンC活性の低い異性体D-アラボアスコルビン酸（D-araboascorbic acid, isoascorbic acid, erythorbic acid）と区別する．還元剤としての活性は同じである．食品の抗酸化剤，肉の色調保持など，食品添加物としても有用で，米国ではGRAS物質扱い．欠乏症は食欲不振，成長遅滞，免疫力低下，骨格筋の萎縮，溶血などの症状が出る．欠乏するとプロリンの酸化が進まないことから，オキシゲナーゼ活性に必須とされている．ヒト血漿の正常値は0.6〜1.6mg/dl．第六次改定日本人の栄養所要量では18歳以上で男女とも1日100mgとされている． アスコルビン酸欠乏症では貧血のほか、骨の発育障害や創傷治癒の遅れなどもみられるが、これらはコラーゲンとコンドロイチン硫酸の合成障害によるものである。アスコルビン酸は腸から容易に吸収され、代謝活動の盛んな臓器に多く含まれる。血液中の濃度が1～1.5ミリグラム％（mg/dl）以上になると尿中に排泄(はいせつ)される。1日10ミリグラムが最低必要量で、イギリスでは20ミリグラム、アメリカでは70ミリグラムを摂取基準としている。なお、動物の場合は大量に与えても毒性は低い。 | | 化粧品の成分用途 | pH調整剤、皮膚コンディショニング剤、酸化防止剤、香料 | | 効能 | 壊血病治療薬, ビタミンC補充薬 | | 商品名 | アスコルビン酸 (コーアイセイ); アスコルビン酸 (コーアイセイ); アスコルビン酸 (ニプロ); アスコルビン酸 (丸石製薬); アスコルビン酸 (健栄製薬); アスコルビン酸 (吉田製薬); アスコルビン酸 (山善製薬); アスコルビン酸 (岩城製薬); アスコルビン酸 (日医工); アスコルビン酸 (日医工); アスコルビン酸 (日興製薬); アスコルビン酸 (日興製薬); アスコルビン酸 (日興製薬); アスコルビン酸 (東和薬品); アスコルビン酸 (東和薬品); アスコルビン酸 (武田薬品工業); アスコルビン酸 (沢井製薬); アスコルビン酸 (紘一製薬); アスコルビン酸 (鶴原製薬); アスコルビン酸 (鶴原製薬); ハイシー (武田テバ薬品); ビタC (共和クリティケア); ビタC (共和クリティケア); ビタシミン (武田テバ薬品); ビタミンC (扶桑薬品工業); ビタミンC (扶桑薬品工業); ビタミンC (扶桑薬品工業) | | 使用上の注意 | 不活性ガス封入 | | 説明 | Ascorbic acid, a water-soluble dietary supplement, is consumed by humans more than any other supplement. The name ascorbic means antiscurvy and denotes the ability of ascorbic to combat this disease. Vitamin C is the l-enantiomer of ascorbic acid. Ascorbic acid deficiency in humans results in the body’s inability to synthesize collagen, which is the most abundant protein in vertebrates. | | 説明 | L-Ascorbic acid is a naturally occurring electron donor and therefore serves as a reducing agent. It is synthesized from glucose in the liver of most mammalian species, excluding humans, non-human primates, or guinea pigs who must obtain it through dietary consumption. In humans, L-Ascorbic acid acts as an electron donor for eight different enzymes, including those related to collagen hydroxylation, carnitine synthesis (which aids in the generation of adenosine triphosphate), norepinephrine synthesis, tyrosine metabolism, and amidating peptides. L-Ascorbic acid demonstrates antioxidant activity that may be of some benefit for reducing the risk of developing chronic diseases such as cancer, cardiovascular disease, and cataracts. | | 化学的特性 | White crystals (plates or needles). Soluble in water; slightly soluble in alcohol;
insoluble in ether, chloroform, benzene, petroleum
ether, oils and fats. Stable to air when dry. One
international unit is equivalent to 0.05 milligram of
l-ascorbic acid. | | 物理的性質 | Appearance: white crystal or crystalline powder, and it is odorless and flavors sour. The color changes yellowish when exposed in the air for a long time. Its aqueous solution is acidic reaction. Solubility: vitamin C is soluble in water, slightly soluble in ethanol, and insoluble in chloroform or ether. Melting point: 190–192? °C.? It would decompose when it melts. Specific optical rotation: +20.5 to +21.5°. Ascorbic acid is two-base acid (the pKa is 4.1 and 11.8). It occurs mainly in the form of sodium salt and calcium salt, and its aqueous solution is strongly acidic reaction. Ascorbic acid is a strong reducing agent. | | Originator | Ascorbic aci,Natur Product,France | | 来歴 | Vitamin C is a general term for compounds having ascorbic acid activity, including ascorbic acid, dehydroascorbic acid, and its isomers.
The understanding of vitamin C has gone through a long and painful process. Although the relationship between scurvy and stored food is obvious, but the
treatments of this disease have been misguided. By 1601, British armed Captain
James Lancaster discovered the disease on the ship of the East India Company and
regarded the scurvy as “rot,” which could be made tissue alkaline.
At the early stage of the nineteenth century, the understanding and treatment of scurvy had developed to a right approach. The exposition of
scurvy etiology and metabolic theory took more than a century.
By the early stage of the twentieth century, inspired by the animal model of beriberi, researchers in the Christchurch Oslo University discovered one animal that
could suffer scurvy accidentally and then established a valuable scurvy animal
model. This experiment demonstrated that the extract isolated from lemon had antiscurvy activity. Until 1932, many research groups obtained the anti-scurvy crystal
from different plants and identified the crystal as ascorbic acid vitamin C. Next year,
the chemical structure of ascorbic acid was elucidated, and then its artificial synthesis was accomplished.
| | 使用 | antiscorbutic, antiviral | | 使用 | vitamin C is a well-known anti-oxidant. Its effect on free-radical formation when topically applied to the skin by means of a cream has not been clearly established. The effectiveness of topical applications has been questioned due to vitamin C’s instability (it reacts with water and degrades). Some forms are said to have better stability in water systems. Synthetic analogues such as magnesium ascorbyl phosphate are among those considered more effective, as they tend to be more stable. When evaluating its ability to fight free-radical damage in light of its synergistic effect with vitamin e, vitamin C shines. As vitamin e reacts with a free radical, it, in turn, is damaged by the free radical it is fighting. Vitamin C comes in to repair the free-radical damage in vitamin e, allowing e to continue with its free-radical scavenging duties. Past research has indicated that high concentrations of topically applied vitamin C are photoprotective, and apparently the vitamin preparation used in these studies resisted soap and water, washing, or rubbing for three days. More current research has indicated that vitamin C does add protection against uVB damage when combined with uVB sunscreen chemicals. This would lead one to conclude that in combination with conventional sunscreen agents, vitamin C may allow for longer-lasting, broader sun protection. Again, the synergy between vitamins C and e can yield even better results, as apparently a combination of both provides very good protection from uVB damage. However, vitamin C appears to be significantly better than e at protecting against uVA damage. A further conclusion is that the combination of vitamins C, e, and sunscreen offers greater protection than the sum of the protection offered by any of the three ingredients acting alone. Vitamin C also acts as a collagen biosynthesis regulator. It is known to control intercellular colloidal substances such as collagen, and when formulated into the proper vehicles, can have a skin-lightening effect. Vitamin C is said to be able to help the body fortify against infectious conditions by strengthening the immune system. There is some evidence (although debated) that vitamin C can pass through the layers of the skin and promote healing in tissue damaged by burns or injury. It is found, therefore, in burn ointments and creams used for abrasions. Vitamin C is also popular in anti-aging products. Current studies indicate possible anti-inflammatory properties as well. | | 使用 | The starting point for synthesis of vitamin C is the selective of oxidation
of the sugar compound D-sorbit to L-sorbose using Acetobacter suboxidans
bacteria. L-sorbose is then converted to L-ascorbic acid, better
known as vitamin C. | | 使用 | analgesic, antipyretic | | 使用 | Sodium, potassium, and calcium salts of ascorbic acids are called ascorbates and are used as food preservatives. To make ascorbic acid fat-soluble, it can be esterified. Esters of ascorbic acid and acids, such as palmitic acid to form ascorbyl palmitate and stearic acid to form ascorbic stearate, are used as antioxidants in food, pharmaceuticals, and cosmetics. Ascorbic acid is also essential in the metabolism of some amino acids. It helps protect cells from free radical damage, helps iron absorption, and is essential for many metabolic processes. | | 使用 | Physiological antioxidant. Coenzyme for a number of hydroxylation reactions; required for collagen synthesis. Widely distributed in plants and animals. Inadequate intake results in deficiency syndrome
s such as scurvy. Used as antimicrobial and antioxidant in foodstuffs. | | 適応症 | Vitamin C (ascorbic acid) is essential for the maintenance
of the ground substance that binds cells together
and for the formation and maintenance of collagen.The
exact biochemical role it plays in these functions is not
known, but it may be related to its ability to act as an
oxidation–reduction system. | | 調製方法 | Ascorbic acid is produced synthetically using the Reichstein process, which has been the standard method of production since the 1930s. The process starts with fermentation followed by chemical synthesis. The first step involves reduction of D-glucose at high temperature into D-sorbitol. D-sorbitol undergoes bacterial fermentation, converting it into L-sorbose. L-sorbose is then reacted with acetone in the presence of concentrated sulfuric acid to produce diacetone-L-sorbose, which is then oxidized with chlorine and sodium hydroxide to produce di-acetone-ketogulonic acid (DAKS). DAKS is then esterified with an acid catalyst and organics to give a gulonic acid methylester. The latter is heated and reacted with alcohol to produce crude ascorbic acid, which is then recrystallized to increase its purity. Since the development of the Reichstein process more than 70 years ago, it has undergone many modifications. In the 1960s, a method developed in China referred to as the two-stage fermentation process used a second fermentation stage of L-sorbose to produce a different intermediate than DAKS called KGA (2-keto-L-gulonic acid), which was then converted into ascorbic acid. The two stage process relies less on hazardous chemicals and requires less energy to convert glucose to ascorbic acid. | | 定義 | ChEBI: L-ascorbic acid is the L-enantiomer of ascorbic acid and conjugate acid of L-ascorbate. It has a role as a coenzyme, a flour treatment agent, a food antioxidant, a plant metabolite, a cofactor, a skin lightening agent and a geroprotector. It is an ascorbic acid and a vitamin C. It is a conjugate acid of a L-ascorbate. It is an enantiomer of a D-ascorbic acid. | | Manufacturing Process | D-Glucose was reduced to the D-sorbitol with a hydrogen over Ni Raney, then
it was turned into the L-sorbose with the acetobacter suboxydans and the
hydroxyl groups of L-sorbose were protected with acetone treatment yielded
the diaceton-L-sorbose. Subsequent treatment with NaOCl/Raney Ni produced
di-O-isopropylidene-2-oxo-L-gulonic acid. Partial hydrolysis with aqueous HCl
gave deprotected 2-oxo-L-gulonic acid, which yielded ascorbinic acid by
heating with HCl. | | brand name | Ascorbin (Marion Merrell Dow). | | Therapeutic Function | Vitamin | | 一般的な説明 | Scurvy (from the French word scorbutus) has been recognized as a disease afflicting mankind for thousands of years. Citrus fruits such as oranges, lemons, and limes were later identified as equally effective treatments. Only within the last 100 years has a deficiency in vitamin C been definitively identified as the cause of scurvy. In 1932, Waugh and King isolated crystalline vitamin C from lemon juice and showed it to be the antiscorbutic factor present in each of these treatments.
The structure and chemical formula of vitamin C was identified in 1933 by Hirst et al.Because humans are one of the few animal species that cannot synthesize vitamin C, it has to be available as a dietary component. Dietary sources of ascorbic acid include fruits (especially citrus fruits), vegetables (especially peppers), and potatoes. Although the sources of some commercial products are rose hips and citrus fruits, most ascorbic acid is prepared synthetically.
Vitamin C is now commonly referred to as ascorbic acid because of its acidic character and its effectiveness in the treatment and prevention of scorbutus (scurvy). The acidic character is because of the two enolic hydroxyls; the C3 hydroxyl has a pKa value of 4.1, and the C2 hydroxyl has a pKa of 11.6. All biological activities reside in L-ascorbic acid; therefore, all references to vitamin C, ascorbic acid, ascorbate, and their derivatives refer to this form. The monobasic sodium salt is the usual salt form. | | 一般的な説明 | White to very pale yellow crystalline powder with a pleasant sharp acidic taste. Almost odorless. | | 空気と水の反応 | May be sensitive to prolonged exposure to air and light. Sensitive to moisture. Soluble in water. Aqueous solutions are oxidized by air in a reaction that is accelerated by alkalis, iron and copper. The rate depends on the pH and on oxygen concentration. Also subject to degradation under anaerobic conditions. | | 反応プロフィール | L(+)-Ascorbic acid is a lactone. Reacts as a relatively strong reducing agent and decolorizes many dyes. Forms stable metal salts. Incompatible with oxidizers, dyes, alkalis, iron and copper. Also incompatible with ferric salts and salts of heavy metals, particularly copper, zinc and manganese . | | 火災危険 | Flash point data for L(+)-Ascorbic acid are not available; however, L(+)-Ascorbic acid is probably combustible. | | Biochem/physiol Actions | L-ascorbic acid mainly exhibits antioxidant properties. It protects plants from oxidative stress and mammals from diseases associated with oxidative stress. L-ascorbic acid mainly protects from hydroxyl radicals, superoxide and singlet oxygen. In addition, it also reduces the membrane-linked antioxidant α-tocopherol (oxidised form). L-Ascorbic acid enhances endothelium-dependent vasodilation in various disorders, including diabetes, coronary artery disease, hypertension and chronic heart failure. | | 薬理学 | Vitamin C is considered as a classical enzyme cofactor or antioxidant but also as a transition material in metal ion reaction. And all of these functions of vitamin C are related to the property of antioxidation. | | 臨床応用 | Vitamin C is found in fresh fruit and vegetables. It is
very water soluble, is readily destroyed by heat, especially
in an alkaline medium, and is rapidly oxidized in
air. Fruit and vegetables that have been stored in air, cut
or bruised, washed, or cooked may have lost much of
their vitamin C content.
The deficiency disease associated with a lack of
ascorbic acid is called scurvy. Early symptoms include
malaise and follicular hyperkeratosis. Capillary fragility
results in hemorrhages, particularly of the gums.
Abnormal bone and tooth development can occur in
growing children.The body’s requirement for vitamin C
increases during periods of stress, such as pregnancy
and lactation. | | 臨床応用 | Vitamin C is indicated for the treatment and prevention of known or suspect deficiency. Although scurvy occurs infrequently, it is seen in the elderly, infants, alcoholics, and drug users.Ascorbate can also be used to enhance absorption of dietary nonheme iron or iron supplements. Ascorbic acid (but not the sodium salt) was historically used to acidify the urine as a result of excretion of unchanged ascorbic acid, although this use has fallen into disfavor. Ascorbate also increases iron chelation by deferoxamine, explaining its use in the treatment of iron toxicity. | | 副作用 | Megavitamin intake of vitamin C may result in diarrhea
due to intestinal irritation. Since ascorbic acid is
partially metabolized and excreted as oxalate, renal oxalate
stones may form in some patients. | | 毒性学 | L-Ascorbic acid, or vitamin C, is widely present in plants. The structures of ascorbic acid and dehydroascorbic acid are shown in Figure 10.5. Vitamin C is not only an important nutrient but is also used as an antioxidant in various foods. However, it is not soluble in fat and is unstable under basic conditions. Vitamin C reduces cadmium toxicity and excess doses prolong the retention time of an organic mercury compound in a biological system. Overdoses of vitamin C (106 g) induce perspiration, nervous tension, and lowered pulse rate. WHO recommends that daily intake be less than 0.15 mg/kg. Toxicity due to ascorbic acid has not been reported. Although repeated intravenous injections of 80 mg dehydroascorbic acid was reported to be diabetogenic in rats, oral consumption of 1.5 g/day of ascorbic acid for six weeks had no effect on glucose tolerance or glycosuria in 12 normal adult males and produced no change in blood glucose concentrations in 80 diabetics after five days. The same report noted that a 100-mg intravenous dose of dehydroascorbic acid given daily for prolonged periods produced no signs of diabetes. Ascorbic acid is readily oxidized to dehydroascorbic acid, which is reduced by glutathione in blood. | | 安全性プロファイル | Moderately toxic by
ingestion and intravenous routes. Human
systemic effects by intravenous route: blood,
changes in tubules (including acute renal
failure, acute tubular necrosis). An
experimental teratogen. Other experimental
reproductive effects. Mutation data
reported. When heated to decomposition it
emits acrid smoke and irritating fumes. | | target | p53 | DNA/RNA Synthesis | Mdm2 | | 代謝 | Ascorbic acid is reversibly oxidised to dehydroascorbic
acid; some is metabolised to ascorbate-2-sulfate, which is
inactive, and oxalic acid which are excreted in the urine.
Ascorbic acid in excess of the body's needs is also rapidly
eliminated unchanged in the urine; this generally occurs
with intakes exceeding 100 mg daily. | | 純化方法 | Crystallise it from MeOH/Et2O/pet ether [Herbert et al. J Chem Soc 1270 1933]. [Beilstein 18/5 V 26.] | | Toxicity evaluation | Metabolism of ascorbic acid can lead to deposition of oxalate
crystals in kidney tissue. Reduction of carcinogenic Cr(VI) by
ascorbic acid generates ascorbate–Cr(III)–DNA cross-links that
have been linked to mutagenicity and the formation of DNA
lesions. Uranyl acetate–ascorbate has also been shown to nick
plasmid DNA. |
|