• 제목/요약/키워드: a-tocopherol

검색결과 753건 처리시간 0.024초

Stabilization of Retinol through Incorporation into Liposomes

  • 이승철;육현균;이동훈;이경은;황용일;Richard D. Ludescher
    • BMB Reports
    • /
    • 제35권4호
    • /
    • pp.358-363
    • /
    • 2002
  • Chemical and photochemical processes during storage and preparation rapidly degrade retinol, the most active form of vitamin A. therefore, the efficacy of incorporation into liposomes in order to modulate the kinetics of retinol degradation was investigated. Retinol was readily incorporated into multilamellar liposomes that were prepared form soybean phosphatidylcholine; the extent of the incorporation was 98.14±0.93% at pH 9.0 at a ratio of 0.01 : 1 (wt:wt) retinol : phospholipid. It was only marginally lower at higher retinol concentrations. The pH of the hydration buffer had a small effect. The incorporation efficiency ranged from 99.25±0.47% at pH 3 to 97.45±1.13% at pH 11. The time course of the retinol degradation in the aqueous solution in liposomes was compared to that of free retinol and free retinol with α-tocopherol under a variety of conditions of pH(3, 7, and 11), temperature(4, 25, 37, and 50℃), and light exposure(dark, visible, and UV). The retinol that was incorporated into the liposomes degraded significantly slower than the free retinol or retinol with α-tocopherol at pH 7 and 11. At pH 3, where the free retinol degrades rapidly, the degradation kinetics were similar in liposomes and the presence of α-tocopherol. At pH 7.0 and 4℃ in the light, for example, free aqueous retinol was completely degraded within 2 days, while only 20% of the retinol in the liposomes were degraded after 8 days. In general, the protective effect of the liposome incorporation was greater at low temperatures, at neutral and high pH, and in the dark. The results suggest that protection is greater in the solid, gel phase than in the fluid liquid crystalline phase lipids. These results indicate that the incorporation into liposomes can extend the shelf-life of retinol under a variety of conditions of temperature, pH, and ambient light conditions.

Status of Oxidative Stress and Antioxidant Levels in Smokers with Breast Cancer from Western Nepal

  • Nagamma, T.;Baxi, Jalaj;Singh, P.P.
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제15권21호
    • /
    • pp.9467-9470
    • /
    • 2014
  • Background: Research indicates that oxidative stress induced by smoking plays a role in breast cancer. In view of these reports, we aimed to study th relationship between smoking and oxidative stress in breast cancer patients from the western region of Nepal. Materials and Methods: The study included a control group of 42 females (non-smoking healthy women) and a test group sudivided into Group I consisting of 46 female breast cancer patients who were smokers and Group II consisting of 42 non-smoking breast cancer patients. Detailed history of the patients was collected with the help of pre-test proforma. Plasma levels of malondialdehyde (MDA), total antioxidant activity (TAA) which represents total dietary antioxidants, vitamin C and ${\alpha}$- tocopherol were estimated by standard methods. Statistical analysis was done using SPSS version 16. Results: The plasma MDA, TAA, vitamin C and ${\alpha}$- tocopherol were $1{\pm}1.4nmol/ml$, $918{\pm}207{\mu}mol/L$, $1{\pm}0.24mg/dL$ and $0.94{\pm}0.31mg/dL$ in controls, $5{\pm}1.2nmol/ml$, $458{\pm}166{\mu}mol/L$, $0.64{\pm}0.32mg/dL$ and $0.5{\pm}0.3mg/dL$ in Group-I and $2.56{\pm}1.2nmol/ml$, $663{\pm}178{\mu}mol/L$, $0.78{\pm}0.2mg/dL$ and $0.77{\pm}0.2mg/dL$ in Group- II, respectively. Vitamin C, ${\alpha}$- tocopherol and TAA (p=0.001) were significantly reduced whereas MDA (p=0.001) was significantly raised in Group-I when compared to controls and Group-II. Conclusions: We observed a significant rise in oxidative stress and low levels of antioxidants in breast cancer patients with smoking habit. It is well known that free radicals facilitate the progression of breast cancer, possibly increasing the risk of progression to the next stage.

인지질막 liposome에 미치는 쑥갓 분획물의 항산화 효과 (Antioxidant Activities of Chrysanthemum coronarium L. Fractions on the Liposomal Phospholipid Membrane)

  • Bae, Song-Ja;Noh, Ok-Jeong
    • 생명과학회지
    • /
    • 제12권2호
    • /
    • pp.144-150
    • /
    • 2002
  • 쑥갓(Chrsanthemum coronarium L., CC)은 국화과(Compositae)에 속하는 일년생 초본식물로 독특한 향기를 가진 지중해 원산 식물이다. 우리 나라에는 중국을 거쳐 조선초기에 전해졌으며 시기용으로 널리 애용되고 있다. 본 연구는 쑥갓의 메타놀 분획물(CCMM), 헥산분획물(CCMH), 에틸아세테이트 분획물(CCMEA), 부타놀분획물 (CCMB) 및 수층인 CCMA 분획물을 얻고 각각 일정량을 불포화인지질인 L-$\alpha$-dilinoleoylphosphatidylcholine(DLPC) liposome에 가하고 benzoyl peroxide를 가하여 산화시켜 분광광도법에 의하여 산화지수 ( $A_{234nm}$/ $A_{202nm}$)를 측정 비교하였다. 그 결과 쑥갓의 각 분획물 일정량을 가한 경우의 DLPC liposome의 산화지수는 시료를 가하지 않은 경우보다 낮아 높은 항산화력을 나타내었으나 강한 항산화제인 BHT를 가한 경우 보다는 항산화 정도가 낮았다. 그러나 특히 본 연구에서 알려진 결과로는 쑥갓 분획물들의 항산화력이 널리 알려진 항산화제인 $\alpha$-tocopherol을 가한 경우와 그 효과가 비슷하여 식용으로 애용되고 있는 쑥갓의 항산화적 생리활성이 본 연구에서 입증되었으며 이 효과를 기초로하여 식물 속의 항산화성을 이용한 식품의 개발이 기대 된다.

Effects of applying antioxidants on bond strength of bleached bovine dentin

  • Whang, Hyo-Jin;Shin, Dong-Hoon
    • Restorative Dentistry and Endodontics
    • /
    • 제40권1호
    • /
    • pp.37-43
    • /
    • 2015
  • Objectives: Some antioxidants are believed to restore dentin bond strength after dental bleaching. This study was done to evaluate the influence of antioxidants on the bond strength of bleached bovine dentin. Materials and Methods: Thirty incisors were randomly assigned to 10 groups (two unbleached control and eight bleached groups:immediate bonding IB, 4 wk delayed bonding DB, 10% sodium ascorbate treated SA, 10% ${\alpha}$-tocopherol treated TP groups). Teeth in half of groups were subjected to thermal stress, whereas the remaining groups were not. Resin-dentin rods with a cross-sectional area of $2.25mm^2$ were obtained and microtensile bond strength was determined at a crosshead speed of 1 mm/min. Fifteen specimens were prepared for SEM to compare the surface characteristics of each group. The change in dentin bond strength from thermal stress and antioxidant treatment was evaluated using two-way analysis of variance (ANOVA) and Sheffe's post hoc test at a significance level of 95%. Results: The control group exhibited the highest bond strength values, whereas IB group showed the lowest value before and after thermocycling. The DB group recovered its bond strength similar to that of the control group. The SA and TP groups exhibited similar bond strength values with those of the control and DB groups before thermocycling. However, The TP group did not maintain bond strength with thermal stress, whereas the SA group did. Conclusions: Applying a 10% sodium ascorbate solution rather than 10% ${\alpha}$-tocopherol solution for 60 sec is recommended to maintain dentin bond strength when restoring non-vitally bleached teeth.

비타민 A와 β-Carotene의 급여가 에탄올의 급성 투여에 의한 흰쥐의 산화적 손상에 미치는 영향 (Effect of Dietary Supplementation of Vitamin A or β-Carotene on Oxidative Damage Induced by Acute Ethanol Administration in Rats)

  • 장정현;양경미;서정숙
    • 한국식품영양과학회지
    • /
    • 제31권1호
    • /
    • pp.81-86
    • /
    • 2002
  • 에탄올 투여에 의한 산화적 손상에 대하여 비타민 A의 보충급여 영향을 조사하고자 흰쥐에게 AIN-76 요구량에 2배 수준으로 retinyl acetate와 $\beta$-carotene을 보충한 식이를 5주간 급여한 후 20% 에탄올 용액(3g/kg B.W)을 급성으로 복강내에 투여하였다. 그런 다음 간조직에서 생성되는 지질과산 화물 함량, 간조직에서의 관련 효소활성도와 항산화비타민의 함량을 분석한 결과는 다음과 같다. 간조직에서의 지질과 산화물 함량은 대조군에 비하여 $\beta$-carotene 공급군에서 유의적인 감소를 나타내었다. 그러나 retinyl acetate 공급군과 $\beta$-carotene 공급군 사이에서의 유의적인 차이를 나타내지 않았다. SOD 활성은 대조군에 비해 retinyl acetate 공급군이 높았고, catalase 활성과 GSH-Px 활성은 실험군 간에 유의적인 차이가 없었다. GST 활성은 에탄올만을 투영한 대조군에 비해 retinyl acetate와 $\beta$-carotene을 공급한 군에서 유의적으로 감소되었다. 간조직 내 retinol 함량은 대조군에 비해 retinyl acetate 공급군에서 유의적으로 높게 나타났으며, 이는 에탄올 급여로 인한 간조직 비타민 A의 소모를 retinyl acetate의 급여로 인해 완화시킨 것으로 여겨진다. 그러나 혈청에서는 실험군 간에 유의적인 차이가 없었다. 간조직내 $\alpha$-tocopherol의 함량은 retinyl acetate와 $\beta$-carotene 공급군에서 증가하는 경향을 나타내었다. 이상의 결과를 종합해 볼 때 금성적인 에탄올의 투여에 대해 retinyl acetate나 $\beta$-carotene을 보충 급여한 경우 항산화효소계 중 superoxide dismutase의 활성이 유도되는 경향을 보였으며, 대표적인 항산화비타민으로 알려진 $\alpha$-tocopherol의 간조직 내 수준이 증가하는 것으로 나타났다.

유색미 겨에 함유된 항산화 효과 관련 기능성 성분의 검정 (Screening of Antioxidation-related Functional Components in Brans of the Pigmented Rices)

  • 강미영;남연주;남석현
    • Applied Biological Chemistry
    • /
    • 제48권3호
    • /
    • pp.233-239
    • /
    • 2005
  • 5품종의 유색미(DZ 78, Elwee, LK1A-2-12-1-1, LK1-3-6-12-1-1, 길림흑미) 겨 70% 에탄올 추출물 및 염화메틸렌 및 에틸아세트로 추출한 지용성 분획들의 DPPH radical 소거활성을 측정하고 페놀성화합물 및 피틴산, 그리고 불검화물로서 retinol, tocopherol과 stigmasterol의 함량을 정량하였다. 또한 GC-MS를 사용하여 염화메틸렌 및 에틸아세트 분획이 함유한 구성분을 동정하고 상대적 함량을 측정함으로써 항산화 활성의 발현에 필요할 것으로 보이는 성분들을 조사하고자 하였다. 그 결과, 유색미의 항산화성은 일반미보다 약 30%정도 더 높았고, 페놀성화합물의 함량은 일반미보다 26배까지 더 많았다. 특히 길림흑미는 retinol이나 tocopherol, stigmasterol 같은 불검화물의 함량이 일반미보다 2.3배 이상 더 많았다. 그러나 항산화성과 색도 및 불검화물의 함량과는 전반적인 상관성은 없었다. 항산화성이 강한 길림흑미 및 LK1A-2-12-1-1의 염화메틸렌 분획은 각각 (Z)-9-Hexadecenyl ester-9-octadecanoic acid 및 2-Hydroxyl-1-1(hydroxymethyl)ethyl-9-octadecanoic acid의 상대적 함량이 높았다. 반면, 에틸아세트 분획에서는 1H Indene과 Methyl ester-tetradecanoic acid 및 Methyl ester-hexadecanoic acid가 5품종 유색미에서 공통적으로 검출되어, 이들 화합물이 항산화성에 관여할 가능성을 시사하였다.

다류원류 식물류의 에탄올 추출물이 대두유의 산화에 미치는 영향 (The Effect of Plant Ethanolic Extracts on Oxidation of Soybean Oil)

  • 김미혜;김명철;박종석;박은지;김종욱;송경희;신동우;목진민;이종옥
    • Journal of Nutrition and Health
    • /
    • 제31권8호
    • /
    • pp.1355-1364
    • /
    • 1998
  • This study was planned to investigate the effect of 40 plant ethanolic extracts on antioxidant activities in vitro. The total phenolics, $\beta$-carotene, $\alpha$-tocopherol and selenium contents were also determined . Antioxidant activities fo the ethanolic extracts(0.02%, w/w) in the soybean oil were measured both by determining the peroxide value (POV) during 35 days of storage at 4$0^{\circ}C$ in a forced draft air-incubator and by determining changes in conductivity at 11$0^{\circ}C$(Rancimat method.). Soybean oil without any additives was used as a control and that treated with 0.02% BHT was used as a positive control. Based on the POV determination, green tea extract was found to be the most effective in stabilizing soybean oil, then followed by long tea, which both of them showed higher antioxidant activities compared to the BHT treatment. The antioxidant activities of them showed higher antioxidant activities compared to the BHT treatment. the antioxidant activities of coffee, cinnamomi cortex, acanthopanacis cortex, black tea, orange peel , instant coffee, peony and crni fructus extracts were stronger compared to the control .By the Rancimat method, green tea leaf and oolong tea leaf, foxglove, acanthopanacis cortex and peony extracts. Compared to other extracts, green tea leaf, black tea leaf, foxglove, acanthopanacis cortex and peony extracts had stronger antioxidative effects in both the POV and Rancimat methods used in this study. ethanolic extracts which showed the stronger antioxidative effect also has the higher contents of total phenolics, $\beta$-carotene, and/or $\alpha$-tocopherol. The antioxidative effect of ethanolic extracts was found to be due to the combined effect of various antioxidants.

  • PDF

대두유로부터 Lipase를 이용한 재구성 지질의 합성 및 특성 (Lipase-Catalyzed Synthesis of Structured Lipids with Capric and Conjugated Linoleic Acid in a Stirred-Batch Type Reactor)

  • 신정아;이기택
    • 한국식품영양과학회지
    • /
    • 제33권7호
    • /
    • pp.1175-1179
    • /
    • 2004
  • Scale-up하기 위하여 24시간동안 1:2:2의 몰 비율로 stirred-batch type reactor에서 합성된 재구성지질은 capric acid와 CLA를 각각 4.9 mol%와 4.1 mot% 함유하였다. 기능성 지방산인 capric acid와 CLA는 주로 TAG의 sn-1,3 position에 분포하였고, sn-2 position에는 linoleic acid가 대부분을 차지하였다. 재구성지질과 대두유의 요오드가는 각각 126와 114이었고, 비누화가는 각각 190과 194로 측정됨으로써, 재구성 지질의 TAG에서 capric acid의 함유를 확인할 수 있었다. 대두유와 재구성지질의 tocopherol함량은 각각 74.6 mg/100 g과 18.2 mg/100 g으로, 재구성지질의 tocopherol 함량은 대두유보다 약 76% 감소하였다. 색도분석 결과, 재구성 지질과 대두유간에 백색도(L*)와 적색도(a*)에서는 유의적 차이가 없었으나(p<0.05),황색도(b*)에서 재구성지질이 대두유보다 좀더 yellowness를 보이며 유의적 차이를 보였다. (p<0.05). Reversed-phase HPLC 분석 결과, 재구성지 질에서 capric acid를 함유하고 있는 TAG형태의 partition number (PN)는 25∼37로 약 12.57 area%이었음을 확인하였다. 대두유의 주된 crystallization peak는 -57.86$^{\circ}C$C이었으나, capric acid를 4.9 mol% 함유하고 있는 재구성지질의 crystallization peak는 -52.78$^{\circ}C$로 대두유보다 결정화가 좀더 고온에서 일어났다.

Effects of Incremental Levels of α-Tocopherol Acetate on Performance, Nutrient Digestibility and Meat Quality of Commercial Broilers

  • Chae, B.J.;Lohakare, J.D.;Choi, J.Y.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • 제19권2호
    • /
    • pp.203-208
    • /
    • 2006
  • This experiment was conducted to explore the efficacy of ${\alpha}$-tocopherol acetate (AT), a commercial supplement containing tocopherols, in commercial broilers. Three hundred and thirty Ross broiler chicks (4-d old) were randomly distributed and allotted to five dietary treatments for six weeks. Each treatment comprised 3 pens as replicates containing 22 chicks per pen. The five dietary treatments were: 0 mg/kg AT (negative control); 10 mg/kg AT; 50 mg/kg AT; 100 mg/kg AT; and 200 mg/kg AT; respectively, supplied totally by the supplement under study. Supplementation of AT improved weight gain significantly (p<0.05), with higher values in the 100 and 200 mg/kg AT fed group than the control during all phases of study, but feed intake remained unaffected. The nutrient digestibility studies conducted after 15 and 35 days of experimental feeding showed significantly higher digestibility of CP, ether extract and gross energy, in these two groups over the control diet. Carcass traits like dressing percentage and the color of the breast meat did not differ significantly due to treatments, but significantly (p = 0.0152) lower abdominal fat percent was noted in the 200 mg/kg fed group. Higher (p = 0.0003) tibia bone strength was noticed in groups fed diets above 50 mg/kg AT because of higher bone mineral content. The serum levels of tocopherols were not influenced but the muscle tocopherols content showed a positive linear trend with the dietary levels supplemented. The thio-barbituric acid reactive substances (TBARS) level in meat also suggested that supplemental AT has a protective role in rancidity. Overall, it could be concluded that AT supplementation at higher levels was found beneficial for growth and increased chicken meat quality.