• 대한화장품학회지
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• 제23권2호
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• pp.97-117
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• 1997

L-Ascorbic acid 및 그 유도체는 항산화 작용과 미백작용 및 섬유아세포의 생장 촉진과 콜라젠 생합성의 증가시키는 효과가 있으므로 화장품에서 오래 전부터 사용되어 왔다. 본 연구에서는 생체에 대한 안전성과 안정성이 우수한 L-Ascorbic acid 유도체를 개발하기 위하여 인지질과 유사하게 L-Ascorbic acid 에 3-Aminopropane phosphoric acid를 결합하여 L-Ascorbic acid-3-aminopropane phosphoric acid diester를 합성하였다. ASA-APPA 는 2-Chlorotetrahydro-2H-1, 3, 2-oxazaphosphorine P-oxide 와 5, 6-isopropylidene L-Ascorbic acid 를 반응 시킨 후 산 사수분해 반응을 통하여 얻을 수 있었다. ASA-APPA는 수용액에서 안정성이 우수하였으며, 독성실험에서 무독성 물질이며, 인체 첩포 실험에서도 무자극 물질임을 확인하였다. 그리고, ASA-APPA 는 L-Ascorbic acid 와 3-APPA 의 혼합물과 거의 유사한 섬유아세포의 증식효과를 나타내었으며, melanoma 에 대한 멜라닌 생성 억제 실험에서 L-Ascorbic acid phosphate magnesium salt 와 유사한 효과를 보였다. 따라서 ASA-APPA 는 멜라닌 생성 억제 효과와 섬유아세포의 증식 효과를 갖는 새로운 화장품 원료로서 사용이 가능할 것으로 생각된다.

• 대한화학회지
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• 제39권1호
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• pp.29-34
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• 1995

구리(II)-아민류 착물에 의한 l-ascorbic acid의 산화반응속도를 pH 4.6에서 Onishi 방법으로 측정하였다. 이 반응의 메커니즘은 l-ascorbic acid가 구리(II) 착물에 배위된 다음 속도결정단계에서, 전자이동이 일어나는 내부권 메커니즘에 따라 반응이 진행됨을 알았다.

• Archives of Pharmacal Research
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• 제26권7호
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• pp.575-580
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• 2003

The present study was designed to develop a microencapsulated L-ascorbic acid and iron that could be used to fortify milk and to determine the sensory properties of milk fortified with microencapuslation. Coating material was medium-chain triacylglycerol (MCT), and selected core material was ferric ammonium sulfate and L-ascorbic acid. The highest efficiency of microencapsulation was 95.0% in the ratio of 15:1 as coating to core material. Ascorbic acid release was increased sharply up to 5 d storage as 6.5%. TBA value was the lowest when both capsulated iron and ascorbic acid were added during 12 d storage, compared with other treatments. In sensory analysis, most aspects were not significantly different between control and capsulated ascorbic acid fortified milk at 5 d storage. The present study indicated that the use of microencapsulated ascorbic acid with MCT is effective for fortifying milk. In addition, these results suggest that acceptable milk products can be prepared with microencapsulated ascorbic acid and iron.

• Bulletin of the Korean Chemical Society
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• 제24권8호
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• pp.1169-1171
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• 2003

A stable derivative of L-ascorbic acid, 2-O-[(3-aminopropyl)phosphinooxy]-L-ascorbic acid (LAAP), was synthesized in moderate yield and its chemical stability and effects on melanin synthesis were investigated. LAscorbic acid was decomposed completely within about 1 hour, while 93% of LAAP remained even after 10 days. Treatment of L-ascorbic acid and LAAP decreased melanin content in normal human melanocytes to 33.8% and 49.1% of control at 2 mM, respectively. Considering chemical instability of L-ascorbic acid, LAAP is a much better whitening agent.

• Journal of Microbiology and Biotechnology
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• 제16권11호
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• pp.1678-1683
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• 2006

A novel suspension-phase enzyme reaction system for the intermolecular transglycosylation of L-ascorbic acid into 2-O-${\alpha}$-D-glucopyranosyl L-ascorbic acid supplementing extrusion starch as the glycosyl donor was developed using cyclodextrin glucanotransferase from Thermoanaerobacter sp. A high conversion yield compared to the conventional soluble-phase enzyme reaction system using cyclodextrins and soluble starch was achieved. The optimal reaction conditions were 2,000 units of cycIodextrin glucanotransferase, 20 g/l of L-ascorbic acid, and 50 g/l of extrusion starch at $50^{\circ}C$ for 24 h. The new suspension-phase enzyme reaction system also exhibited several distinct advantages other than a high conversion yield, including a lower accumulation of oligosaccharides and easily separable residual extrusion starch by centrifugation or filtration in the reaction mixture, which will facilitate the purification of 2-O-${\alpha}$-D-glucopyranosyl L-ascorbic acid. The new suspension-phase enzyme reaction system seems to be potentially applicable as the industrial process for the production of thermally and oxidatively stable 2-O-${\alpha}$-D-glucopyranosyl L-ascorbic acid.

• 한국식품영양과학회지
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• 제28권4호
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• pp.954-957
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• 1999

The changes in L ascorbic acid content by processing treatments; gamma irradiation, heating and microwave were investigated using high performance liquid chromatography. The content of L ascorbic acid in standard solutions and citrus fruits decreased from 27.4 to 44.9% and from 6.9 to 21.9%, re spectively, by gamma irradiation doses in the range of 1 to 10 kGy. By heating treatments, L ascorbic acids in standard solutions and citrus fruits were destroyed 22.5 to 36.8% and 4.5 to 18.1%, respectively. By microwave treatment, L ascorbic acid content also decreased from 23.1 to 47.4% and from 6.5 to 22.6%, respectively.

• 분석과학
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• 제7권2호
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• pp.149-153
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• 1994

Squash-조직을 graphite rod disk 전극에 고정하여 메탄올 용매 속에서 L-ascorbic acid(AA)를 정량할 수 있는 전류법 바이오센서를 만들었다. 전극의 검출한계는 $2{\times}10^{-6}M$이었다. 순수한 ascorbate oxidase(AO)를 고정시켜 만든 전극에 비해 식물 조직에 들어 있는 효소로 만든 이 전극은 생촉매의 활성도가 높고 안정성이 좋았으며(1주간) 대단히 값싸게 만들 수 있었다.

• Applied Biological Chemistry
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• 제47권2호
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• pp.187-191
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• 2004

Ascorbic acid로부터 $2-O-{\alpha}-D-glucopyranosyl-L-ascorbic$ acid(ascorbic acid-2-glucoside, AA-2G)를 생산하기 위하여, transglucosylation 활성을 가지는 시금치 종자의 ${\alpha}-glucosidase$를 효소원으로 이용하였다. 시금치 종자로 사용한 Spinachia oleracea L. WooSung의 조효소액의 ${\alpha}-glucosidase$ 활성은 발아 후 3일 째에 가장 높게 나타났으며, AA-2G의 생산은 2일 키운 시금치의 조효소액을 이용하였을 때, 생산량이 1.053 mM로 가장 높았다. 조효소액을 이용한 AA-2G 생산에 있어서 glucose 공여체로는 maltose가 가장 좋았으며, maltose와 ascorbic acid의 최적 농도는 각각 225 mM과 175 mM이었다. ${\alpha}-glucosidase$는 60 unit를 사용했을 때 생산량이 가장 좋았다. 효과적인 반응완충용액은 sodium acetate 완충액이었으며, 최적 농도는 175 mM이었다. 최적 pH및 반응온도는 각각 5.0과 $65^{\circ}C$였고, 최적 반응조건 하에서 50분 반응 후에 ascorbic acid로부터 2.30 mM의 AA-2G가 생산되었다.

• 미생물학회지
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• 제23권4호
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• pp.302-308
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• 1985

L-Ascorbic aciddm ltodcp 산화분해과정중 ${\alpha}$-ketoaldehyde의 한 종류인 3,4,5-trihydroxy-2-keto-L-valeral-dehyde(L-xylosone)가 형성된다는 사실을 핵자기공명스펙트럼분석법으로 확인하였다. 이 물질은 glyoxalase system에 의해 L-xylonic acid로 변환되고 계속해서 L-erythroascorbic acid로 산화된다. 이러한 근거 위에서 vitamin C의 분해과정이 vitamic C 이외의 두종류의 ${\gamma}$-lactones-과 3종류의 ${\alpha}$-ketoaldehydes로 구성된 분해경로를 갖는다는 사실을 제안하였다.

• Archives of Pharmacal Research
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• 제11권2호
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• pp.114-121
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• 1988

To gain insight into possible cellular protective mechanisms against the insult of formaldehyde, we have investigated this molecule's reactivity with both naturally occurring thiol compounds including glutathione and L-ascorbic acid. By UV measurements, for maldehyde was found to rapidly react with glutathione forming an S-hydroxymethyl covalent adduct. The adduct which was confirmed by NMR is transiently stable. Formaldehydissimilar to its reaction with dimedone. The reaction of formaldehyde with glutathione was reduced by 40% in the presence of an excess amount of L-ascorbic acid, due to the trapping of formaldehyde by L-ascorbic acid. The data suggest that L-ascorbic acid may have a possible in vivo role in the metabolism of formaldehyde, thereby protecting cellular glutathione from possible depletion.