• 한국미생물·생명공학회지
• /
• 제28권1호
• /
• pp.33-38
• /
• 2000

In order to produce ascorbic acid-2-phosphate from ascorbic acid, bacteria capable of transforming ascorbic acid to ascorbic acid-2-phosphate were isolated from soils and the stock cultures in our laboratory. Among them, a newly isolated bacterium LSH-3 having the best ability of producing ascorbic acid-2-phosphate was selected and partially identified as Pseudomonas sp. The optimum conditions for the production of ascorbic acid-2-phosphate from ascorbic acid and using its resting cells as the source os enzyme were investigated. The results were summarized as follows: The optimum cultivation time and the cell weight for the production of ascorbic acid-2-phosphate was 14 hours and 100g/I(wet weight), respectively. And 0.1%(v/v) Trition X-100 was the most effective surfactant. The optimum concentrations of ascorbic acid and pyrophosphate were 400mM and 500mM, respectively, which led to produce 14.54g/I of ascorbic acid-2-phosphate. The most effective buffer was 50mM sodium acetate. The optimum pH and temperature were 4.5 and $40^{\circ}C$, respectively. Under the above conditions, 17.71 g/I of ascorbic acid-2-phosphate was produced from ascorbic acid after 32 hour-incubation, which corresponded to 17.5% of conversion rate based on ascorbic acid.

• 동의신경정신과학회지
• /
• 제6권1호
• /
• pp.19-39
• /
• 1995

In order to compare the anti-stress effect of Guibitang with that of ascorbic acid, after these medicines were administered to guinea pigs induced by heating and swimming stress, the changes of the weight of body and organ, and content of plasma catecholamines, serum total cholesterol, free cholesterol, triglyceride, protein, glucose and cortisol were measured. The results were as follows : 1. The weight of the body was increased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress. 2. The weight of spleen decreased with statistical significance in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress, but in case of swimming stress, the weight of spleen decreased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. The weight of adrenal decreased with statistical significance in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress alone. 3. Plasma norepinephrine content decreased with statistical significance not only in the groups administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid but in the group administered ascorbic acid with Guibitang as compared with in the group administered ascorbic acid on heating stress. In case of swimming stress, norepinephrine decreased with statistical significance in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 4. Plasma dopamine content decreased with statistical significance only in the group administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress. 5. Serum total cholesterol content decreased with statistical significance in the groups administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress, but in case of swimming stress, it decreased with statistiscal significance only in the group administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 6. Serum triglyceride content decreased with statistical significance not only in the groups administered ascorbic acid, Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid but in the group administered ascorbic acid with Guibitang as compared with in the group adminstered ascorbic acid on heating stress. In case of swimming stress, triglyceride decrease with statistical significance only in the group administered ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid. 7. Serum glucose content increased with statistical significance in the groups administered Guibitang and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on both heating and swimming stress, particulaly in case of swimming stress, in the group administered ascorbic acid with Guibitang, it increased with statistical significance as compared with in the group administered ascorbic acid. 8. Serum cortisol content decreased with statistical significance only in the group administered ascorbic acid and ascorbic acid with Guibitang as compared with in the group administered non ascorbic acid on heating stress.

• Journal of Nutrition and Health
• /
• 제18권4호
• /
• pp.312-317
• /
• 1985

본 연구는 오이의 추출물에서 Ascorbic acid oxidase 활성의 존재유무를 검토하고 이 효소의 특성을 규명하여 Ascorbic acid의 손실을 최소화하는 과채류의 조리, 가공조건을 설정하는데 도움이 되고저 시도 되었다. 오이에서 Ascorbic acid oxidase를 분리해 내어 그 특성을 연구한 결과 시간의 변화에 따른 Ascorbic acid oxidase의 활성은 처음 10분 동안 Ascorbic acid 감소량이 가장 현저하였으며 Ascorbic acid oxidase의 최저 pH는 6.5로 나타났다. 또한 온도의 변화에 따른 Ascorbic acid oxidase의 활성은 $40^{\circ}C$까지는 계속 증가하다가 최적온도 $40^{\circ}C$를 기점으로 그 이상의 온도에서는 감소하였다. 본 연구에서 고찰한 결과를 실제로 적용시켜 오이 juice를 제조하여 온도 및 pH변화에 따른 Ascorbic acid 함량을 비교한 결과 냉장온도에서 $4^{\circ}C$의 물로 blending한 것이 실온의 물로 blending한 것보다 Ascocbic acid 함량이 높았으며 orang juice (pH 34) 를 첨가하여 blending한 것은 Ascorbic acid 함량이 감소되지 않은 것으로 나타났다. 따라서 야채 juice조제시 저온에서 처리하고 pH 를 3.9 이하로 낮추며 juice 조제후 바로 섭취하는 것이 Ascorbic acid의 파괴를 최소화할 수 있는 바람직한 방법이라고 사려된다.

• Archives of Pharmacal Research
• /
• 제26권10호
• /
• pp.874-879
• /
• 2003

The present study was carried out to examine the stability of microencapsulated ascorbic acid in simulated-gastric and intestinal situation in vitro and the effect of microencapsulated ascorbic acid on iron bioavailability. Coating materials used were polyglycerol monostearate (PGMS) and medium-chain triacylglycerol (MCT), and core materials were L-ascorbic acid and ferric ammonium sulfate. When ascorbic acid was microencapsulated by MCT, the release of ascorbic acid was 6.3％ at pH 5 and 1.32％ at pH 2 in simulated-gastric fluids during 60 min. When ascorbic acid was microencapsulated by PGMS, the more ascorbic acid was released in the range of 9.5 to 16.0％. Comparatively, ascorbic acid release increased significantly as 94.7％ and 83.8％ coated by MCT and PGMS, respectively, for 60 min incubation in simulated-intestinal fluid. In the subsequent study, we tested whether ascorbic acid enhanced the iron bioavailability or not. In results, serum iron content and transferring saturation increased dramatically when subjects consumed milks containing both encapsulated iron and encapsulated ascorbic acid, compared with those when consumed uncapsulated iron or encapsulated iron without ascorbic acid. Therefore, the present data indicated that microencapsulated ascorbic acid with both PGMS and MCT were effective means for fortifying ascorbic acid into milk and for enhancing the iron bioavailability.

• 한국식품과학회지
• /
• 제31권2호
• /
• pp.280-284
• /
• 1999

Ascorbic acid의 불안정성을 극복하기 위하여, 탈수화/재수화의 방법을 이용하여 soybean phosphatidyl choline으로 제조한 리포솜에 ascorbic acid를 미세캡슐화하였다. Ascorbic acid는 46.8%의 효율로 리포솜내에 포집되었다. 리포솜 내에서의 ascorbic acid는 수용액에서보다 안정성이 매우 증대되었다. 예로 pH 5.0의 acetate buffer에서의 ascorbic acid는 7일 경과 후에 대부분이 산화되지만, 같은 조건에서 리포솜에 미세캡슐화되었을 경우는 40일이 경과하여도 22.8%가 환원된 상태를 유지하였다. 이러한 결과는 리포솜으로 ascorbic acid를 미세캡슐화하면 저장 기간을 향상시키는 보호 수단으로 이용될 수 있음을 의미한다.

• 대한화장품학회지
• /
• 제25권3호
• /
• pp.67-86
• /
• 1999

기능성 물질로서 다양한 생리적 기능을 가진 ascorbic acid는 구조적으로 불안정하여 쉽게 산화되는데 이러한 ascorbic acid의 산화를 억제하기 위해 리포좀에 순수한 ascorbic acid를 봉입시켜 안정한 리포좀을 제조하였다. 안정한 리포좀의 제조를 위해 cholesterol이나 $\beta$-sitosterol 이 리포좀의 안정화에 미치는 영향을 측정하였으며 ascorbic acid의 산화방지를 위해 항산화제로 butylated hydroxytoluene(BHT), tertiary butylhydroquinone(TBHQ)와 $\alpha$-glycosyl rutin, natural concentrated tocopherol을 사용하였다. 리포좀 제조시 cholesterol이나 $\beta$-sitosterol을 사용한 경우 ascorbic acid의 산화가 감소하였는데 이는 cholesterol이나 $\beta$-sitosterol이 리포좀의 이중막을 강화하여 봉입한 ascorbic acid의 방출을 감소시켜 산화를 방지하는 것으로 생각된다 또한 cholesterol의 농도가 0.3%인 경우 가장 안정한 리포좀이 생성됨을 알 수 있었다. 사용된 항산화제는 ascorbic acid에 대하여 모두 산화억제효과를 나타내었으며 tertiary butylhydroquinone, $\alpha$-glycosyl rutin, butylated hydroxytoluene, natura] concentrated tocopherol 순으로 우수함을 보였다. 그러나 제약 및 화장붐에 사용되는 ascorbic acid의 산화억제에는 효과가 가장 좋은 합성 항산화제인 tertiary butylhydroquinone보다 천연물질에서 추출한 항산화제인 $\alpha$-glycosyl rutin이 더 적합할 것으로 생각된다.

• Archives of Pharmacal Research
• /
• 제26권3호
• /
• pp.237-243
• /
• 2003

We investigated the role of ascorbic acid on the redox status in streptozotocin-induced diabetic rats. In the plasma of diabetic rats, the ratio of reduced/total ascorbic acid was significantly decreased as compared with normal control. Ascorbic acid supplementation increased the reduced and total ascorbic acid contents as compared with diabetic control. In the rutintreatment group, reduced and total contents of ascorbic acid were significantly decreased, however, the ratio of reduced/total contents of ascorbic acid had no difference as compared with diabetic rats. In the insulin-treatment group, this ratio is not significantly different as compared with diabetic control. However, in the insulin plus ascorbic acid treatment group, reduced form and the ratio of reduced/total ascorbic acid were significantly increased as compared with diabetic control. In addition, we measured the contents of malondialdehyde (MDA) in the plasma of diabetic rats. The contents of MDA was increased as compared with normal control, however, in insulin-treatment group, the contents of MDA was decreased as compared with diabetic rats. Ascorbic acid had no effects on the increases of MDA in diabetic rats. In conclusion, plasma ascorbic acid level and its reduced/total ratio reflects the status of the oxidative stress in the diabetic rats. Supplement of ascorbic acid did not correct the ratio of the reduced/total ascorbic acid. However, supplement of insulin and ascorbic acid corrected the ratio of reduced/total ascorbic acid.

• Journal of Nutrition and Health
• /
• 제15권1호
• /
• pp.22-29
• /
• 1982

As sugar and amino acid were added to the ascorbic acid solution the content of ascorbic acid was quantitatively determined by 2, 4-dinitrophenyl hydrazine method. The residual ascorbic acid was shown to increase slightly when sorbose, rhamnose or mannose was added to the ascorbic acid solution whereas residual ascorbic acid was shown to decrease in time to the addition of other sugars. The effects of amino acid to the ascorbic acid solution were found that monoamino-mono, or dicarboxylic acids and aromatic amino acids increased the residual ascorbic acidity whereas diamino-monocarboxylic acids and sulfur containing amino acids decreased the residual ascorbic acidity.

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

• 한국미생물·생명공학회지
• /
• 제25권3호
• /
• pp.271-276
• /
• 1997

An ascorbic acid phosphorylating enzyme, which catalyzes the formation of ascorbic acid-2-phosphate from ascorbic acid and pyrophosphate, was purified 32.7-folds to homogeneity from a cell-free extract of Cellulomonas sp. AP-7. The combination of DEAE- Sephacel ion exchange chromatography and Sephacryl S-200 get filtration was used for their purification. The molecular weight of the native protein was estimated to be 96.lkDa on high performance gel filtration chromatography. The SDS-PAGE analysis indicated that the protein consisted of four identical subunits of 24.6 kDa. The purified enzyme showed the optimal tempeature of 40$\circ$C and optimal pH of 4.5. The Km for ascorbic acid and pyrophosphate were 119 mM and 11.9 mM, respectively. The addition of 5,5'-dithiobis-(2-nitrobenzoic acid) into the reaction mixture resulted in the reduction of the enzyme activity at 51%. The enzyme also had a phosphatase activity at weakly acidic pH and the Km for ascorbic acid-2-phosphate in phosphatase activity was 7.9 mM.