共查询到16条相似文献,搜索用时 109 毫秒
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电子烟已成为国际烟草关注的焦点和发展的热点,也是我国烟草行业新型烟草制品发展的一个重要方向。对近几年国内外关于电子烟烟液、烟具和气溶胶中化学成分的风险研究文献和相关法规的进行了收集、分类、比较和分析,从以下三个方面对电子烟中化学成分风险研究现状进行阐述,以期为电子烟安全性研究提供参考:1)烟液和气溶胶中烟碱、醛酮类化合物、挥发性化合物、烟草特有亚硝胺和金属元素等相关研究;2)电子烟气溶胶与卷烟烟气中有害成分的对比研究;3)烟具中有害成分迁移量的分析研究。 相似文献
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建立双刺参胶囊中紫丁香苷及人参皂苷Rg1、Re、Rb1的高效液相色谱法(HPLC)含量测定方法。分别采用依利特APS和Nano-Micro UniSil 5-120 C18色谱柱,以乙腈-水为流动相,梯度洗脱,流速1.0 mL/min,进样量10 μL,人参皂苷Rg1、人参皂苷Re及人参皂苷Rb1在柱温35 ℃、波长203 nm下,紫丁香苷在柱温30 ℃、波长265 nm下进行检测。结果表明:人参皂苷Rg1、人参皂苷Re、人参皂苷Rb1及紫丁香苷分别在15.30~306.00 μg/mL(R2=0.9999)、16.95~339.00 μg/mL(R2=1.0000)、18.45~369.00 μg/mL(R2=1.0000)和4.60~46.00 μg/mL(R2=0.9999)范围内呈现良好的线性关系,其检出限分别为0.77、0.89、0.93、0.12 μg/mL;其定量限分别为2.21、2.71、2.74、0.38 μg/mL。其精密度实验的RSD值分别为1.30%、1.21%、1.99%、0.79%;其重复性实验的RSD值分别为2.49%、2.35%、2.55%、0.80%;其平均加样回收率分别为100.13%、100.50%、102.33%、101.55%,其RSD值分别为0.67%、0.99%、0.29%、0.68%。实验结果表明供试品溶液在48 h内稳定,该方法专属性高、重复性好,可用于双刺参胶囊中紫丁香苷及人参皂苷Rg1、人参皂苷Re、人参皂苷Rb1的含量测定。本实验为双刺参胶囊的质量标准制定提供了基础数据。 相似文献
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本文对比研究了五种果汁中维生素C与总酚含量,采用高效液相色谱法测定了果汁中的酚类组成,并采用化学法和细胞法评价了果汁的抗氧化和抗肿瘤细胞增殖活性。刺梨汁的维生素C含量最高,为14.13 g/L。刺梨汁和沙棘汁的总酚含量最高,分别为13.06和12.53 g GAE/L,且二者无显著性差异(P>0.05)。从5种果汁中共鉴定出没食子酸、芦丁、儿茶素和阿魏酸这4种多酚类化合物。果汁的抗氧化活性与没食子酸含量、总酚含量有显著相关性,其中,沙棘汁、刺梨汁和蓝莓汁果汁的过氧化氢自由基清除能力(PSC)和氧自由基吸收能力(ORAC)较高,柠檬汁和柑橘汁的较低且二者间无显著性差异(P>0.05);PBS冲洗前后,果汁的抗细胞氧化活性(CAA)最高的分别为刺梨汁(163.96 μmol QE/100 mL)和沙棘汁(82.68 μmol QE/100 mL),沙棘汁的细胞吸收率最高(65.27%)。刺梨汁具有最强的抗肿瘤细胞增殖活性(EC50=5.50 mg/mL)和最低的细胞毒性(CC50>200 mg/mL)。五种果汁可根据多酚物质种类与含量及抗氧化活性分为2类:刺梨汁与沙棘汁;柠檬汁、蓝莓汁和柑橘汁。本研究可为水果精深加工及功能性饮品开发提供理论指导。 相似文献
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以油菜蜜为研究对象,建立了一种同时测定油菜蜜中5种酚类化合物的HPLC-ECD分析方法。采用高效液相色谱电化学检测法,以甲醇(A)和2%醋酸(B))水溶液为流动相,梯度洗脱,流速为1.0mL/min;电化学检测器的工作电位为0.8V;柱温为30℃。5种酚类化合物的浓度分别在6.83×10-2-5.46,9.6×10-2-8.67,1.05×10-1-12,9.1×10-2-7.3,1.63×10-1-13μg/mL内与各自的峰面积呈良好的线性关系(r>0.9997)。样品的加样回收率分别为97.4%,98.6%,99.1%,101.6%,99.3%。 相似文献
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Total Phenolic Compounds, Flavonoids, and Radical Scavenging Activity of 21 Selected Tropical Plants
ABSTRACT: Free radical scavenging activity of 21 tropical plant extracts was evaluated using 1,1-diphenyl-2-picrylhydrazyl assay (DPPH). Total phenolic compounds and flavonoids were determined using Folin–Ciocalteu and HPLC, respectively. Results of the study revealed that all the plants tested exhibited excellent antioxidant activity with IC50 in the range of 21.3 to 89.6 μg/mL. The most potent activity was demonstrated by Cosmos caudatus (21.3 μg/mL) and Piper betle (23.0 μg/mL) that are not significantly different than that of -tocopherol or BHA. L. inermis extract was found to consist of the highest concentration of phenolics, catechin, epicatechin, and naringenin. High content of quercetin, myricetin, and kaempferol were identified in Vitex negundo , Centella asiatica , and Sesbania grandiflora extracts, respectively. Luteolin and apigenin, on the other hand, were found in Premna cordifolia and Kaempferia galanga extracts. Strong correlation ( R = 0.8613) between total phenolic compounds and total flavonoids ( R = 0.8430) and that of antioxidant activity of the extracts were observed. The study revealed that phenolic, in particular flavonoids, may be the main contributors to the antioxidant activity exhibited by the plants.
Practical Application: Potent antioxidant from natural sources is of great interest to replace the use of synthetic antioxidants. In addition, some of the plants have great potential to be used in the development of functional ingredients/foods that are currently in demand for the health benefits associated with their use. 相似文献
Practical Application: Potent antioxidant from natural sources is of great interest to replace the use of synthetic antioxidants. In addition, some of the plants have great potential to be used in the development of functional ingredients/foods that are currently in demand for the health benefits associated with their use. 相似文献