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Plant essential oils and phytoconstituents: An assessment of their antioxidant potentials and possible role in preventing UV induced oxidative skin damage.

机译：植物精油和植物成分：评估其抗氧化能力以及在预防紫外线引起的氧化性皮肤损伤中的可能作用。

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摘要

The formation of reactive oxygen species (ROS) from ultraviolet (UV) exposure has been implicated in skin damage and disease. Skin surface lipids (SSL) may be susceptible to ROS attack and subsequent UV induced oxidative damage because they are located at the skin's surface. The oxidation of squalene, the major polyunsaturated SSL, has been linked to aging, comedone formation, induction of acne, and malonaldehyde (MA) formation. Malonaldehyde is mutagenic and carcinogenic because it reacts with DNA and proteins to form Schiff bases. Antioxidant chemicals in plants may counteract the deleterious effects of UV induced oxidation on SSL. This study evaluated the antioxidant activities of flavonoids, essential oils, and volatile phytoconstituents using the aldehyde/carboxylic acid assay, the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay, and the MA/GC assay.;GC-NPD quantification showed that after derivatization with N-methylhydrazine to form 1-MP, MA levels formed from squalene with 25 mug/mL of (+)-catechin or saponarin were lower than those of squalene with BHT. Anti- and pro-oxidant actions for quercetin were concentration dependent. Among 25 essential oils evaluated in the aldehyde/carboxylic acid assay, GC-FID analyses showed cinnamon leaf and thyme oils (10 mug/mL) displaying 100% inhibition of hexanal oxidation after 40 days, comparable to alpha-tocopherol. Reducing abilities of the oils toward DPPH· were spectrophotometrically assessed at 517 nm in the DPPH· scavenging assay. Clove leaf oil (10 mug/mL) showed greater scavenging activity (72%) than alpha-tocopherol (68%). Activities for thyme, ylang, rose, basil, and jasmine oils ranged from 60%--90% at 200 mug/mL.;GC-MS analyses found that the potent activities for thyme and clove leaf oils were due to thymol and eugenol presence, respectively, as confirmed by the two constituents in the MA/GC assay. Mixtures of thyme, clove leaf, rose, cinnamon leaf, and parsley seed oils were also assessed using the MA as 1-MP assay for synergistic or antagonistic effects. Thyme and clove leaf mixtures showed synergistic activities. Mixtures of thyme with cinnamon leaf or rose oils displayed antagonistic effects. Results suggest that prevention of UV induced in vivo oxidative damage may be helped by thymol and eugenol, and possibly some plant constituents.
机译：紫外线（UV）暴露会形成活性氧（ROS），与皮肤损伤和疾病有关。皮肤表面脂质（SSL）可能位于皮肤表面，因此容易受到ROS的攻击和随后的UV诱导的氧化损伤。角鲨烯（主要的多不饱和SSL）的氧化与老化，粉刺形成，粉刺的诱发和丙二醛（MA）的形成有关。丙二醛具有致突变性和致癌性，因为它与DNA和蛋白质反应形成席夫碱。植物中的抗氧化剂化学物质可以抵消UV诱导的氧化对SSL的有害影响。本研究使用醛/羧酸测定法，1,1-二苯基-2-吡啶并肼基（DPPH）自由基清除测定法和MA / GC测定法评估了类黄酮，精油和挥发性植物成分的抗氧化活性。 NPD定量显示，在用N-甲基肼衍生形成1-MP后，由角鲨烯与25杯/ mL的（+）-儿茶素或皂苷组成的MA水平要低于与BHT的鲨烯。槲皮素的抗氧化和促氧化作用取决于浓度。在醛/羧酸测定法评估的25种精油中，GC-FID分析显示，肉桂叶和百里香油（10杯/毫升）在40天后对己醛氧化的抑制作用为100％，与α-生育酚相当。在DPPH·清除试验中，在517 nm处用分光光度法评估了油对DPPH·的还原能力。丁香叶油（10杯/毫升）显示出比α-生育酚（68％）更大的清除活性（72％）。百里香，依兰，玫瑰，罗勒和茉莉精油的活性在200杯/毫升时为60％-90％; GC-MS分析发现百里香和丁香叶油的有效活性是由于百里香酚和丁香酚的存在分别由MA / GC分析中的两种成分证实。百里香，丁香叶，玫瑰，肉桂叶和香菜种子油的混合物也使用MA作为1-MP分析方法评估了协同或拮抗作用。百里香和丁香叶混合物表现出协同活性。百里香与肉桂叶或玫瑰油的混合物表现出拮抗作用。结果表明，百里酚和丁子香酚以及某些植物成分可能有助于预防紫外线引起的体内氧化损伤。

著录项

  • 作者

    Wei, Alfreda.;

  • 作者单位

    University of California, Davis.;

  • 授予单位 University of California, Davis.;
  • 学科 Agriculture Food Science and Technology.
  • 学位 Ph.D.
  • 年度 2006
  • 页码 152 p.
  • 总页数 152
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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