香水莲花提取物的美白功效研究

天然提取物由于其安全性高,近年来成为化妆品功效研究的热点。通过体外法测定香水莲花提取物所含活性成分及其对酪氨酸酶活性的抑制效果,再采用细胞模型探究其对B16小鼠黑素瘤细胞形态、增殖、黑素含量以及细胞内酪氨酸酶活性的影响。结果显示,黄色、蓝色香莲整花提取物均能有效抑制体外酪氨酸酶活性,其中体积分数60%醇提物能有效减缓B16黑素瘤细胞增殖、抑制黑素合成及胞内酪氨酸酶活性,添加100μg/m L的黄、蓝色整花体积分数60%醇提物的细胞增殖率分别为(84.44±1.77)%、(48.24±3.14)%,黑素质量分数为(69.69±1.40)%、(66.98±2.44)%,具有较好的美白功效。     

姜黄素超分子包合物的体外抗肿瘤活性评价

对姜黄素超分子包合物的体外抗肿瘤活性进行评价。采用Cell Counting Kit-8(CCK-8)比色法检测包合物(40、80、160、320、640 μg/mL)对不同肿瘤细胞(A375黑色素瘤细胞、A549肺癌细胞、Hela宫颈癌细胞和MCF-7乳腺癌细胞)处理不同时间(24、48、72 h)后对其细胞存活率的影响,并进一步运用Annexin-V/PI双染检测包合物抑制肿瘤细胞增殖的原因。结果表明,四种细胞的存活率均随着包合物浓度和处理时间的增加呈下降趋势,并且包合物对A375细胞的增殖具有最强的抑制作用,其IC₅₀达到最低,为476.4 μg/mL。进一步的检测发现,当包合物处理A375细胞后,细胞凋亡的数量随着包合物浓度的升高而升高,从对照组的3.3%上升到35.0%,这表明,包合物通过诱导细胞凋亡来抑制A375细胞增殖。     

松口蘑菌丝体蛋白质诱导细胞凋亡

采用深层发酵技术培养菌丝体并提取分离出的蛋白质,进行体外抗人子宫颈癌HeLa细胞增殖及诱导细胞凋亡机理的研究.试验发现松口蘑菌丝体水提液中活性蛋白质TMP在体外具有抑制肿瘤细胞增殖的作用,扫描电镜观察到TMP处理细胞产生明显的凋亡小体,TMP对细胞周期的影响是通过抑制细胞从S到G2M期的转化来抑制HeLa细胞增殖,诱导细胞发生凋亡的.DNA电泳出现以200bp左右为单位的DNA碎片.结果表明采用液体培养方法生产的松口蘑菌丝体蛋白质,具有显著的抑制细胞增殖和诱导细胞凋亡作用.     

青梅花提取物的酪氨酸酶抑制作用及机理研究

目的：以青梅花为原料,探讨其提取物（PF）在体外对酪氨酸酶的抑制作用及机理。方法：首先采用多巴速率氧化法体外测定PF酪氨酸酶的抑制活性,并绘制Lineweaver-Burk曲线,推断其抑制类型。分别采用化学发光法和铁氰化钾还原法测定PF的清除自由基能力及还原力。结果表明：PF能显著抑制酪氨酸酶活性,其半抑制浓度IC50为（98．89±6．34）ug／mL,抑制类型为混合型抑制。PF对酪氨酸酶的抑制作用可能与提取物中绿原酸等多酚物质、较强的自由基清除能力和还原力有关。结论：PF是一种有前途的酪氨酸酶抑制剂,可应用于果蔬等食品的加工和贮藏。     

番薯叶多酚提取工艺优化及其生物活性研究

为获得番薯叶多酚的最优提取工艺及其体外生物活性,研究乙醇体积分数(A)、提取温度(B)、料液比(C)、提取时间(D)4因素对番薯叶多酚提取量的影响,通过单因素实验和Box-Behnken响应面分析法优化番薯叶中多酚的提取工艺。采用高效液相色谱法测定番薯叶多酚主要成分。以DPPH自由基清除率和FRAP法评价番薯叶多酚总抗氧化能力,以α-淀粉酶和α-葡萄糖苷酶抑制试验评价番薯叶多酚体外降糖能力。结果表明:番薯叶多酚最佳提取条件为:乙醇体积分数88%,提取温度57 ℃,料液比1∶20,提取时间30 min,此时番薯叶中多酚的实际提取量为(15.34±0.19)mg GAE/g。番薯叶多酚主要单体酚为5-咖啡酰奎宁酸、3-咖啡酰奎宁酸、4-咖啡酰奎宁酸、3,4-咖啡酰奎宁酸、3,5-咖啡酰奎宁酸、4,5-咖啡酰奎宁酸、3,4,5-咖啡酰奎宁酸。抗氧化活性试验及体外降糖试验结果表明:番薯叶多酚具有较好的抗氧化活性和体外降糖活性,在最优提取条件下其DPPH自由基清除能力和FRAP总抗氧化能力分别为11.57 mg TE/g和12.30 mg TE/g,对α-淀粉酶与α-葡萄糖苷酶的抑制率分别为89.94%和22.28%。     

玫瑰蜂花粉中不同存在形态酚类物质的组成及其抑制B16黑色素瘤细胞的活性

本文研究了玫瑰蜂花粉中游离态和结合态酚酸类物质含量和组成;采用铁离子还原能力、ABTS和DPPH自由基清除能力三种模型评价其抗氧化能力;同时测定了其对蘑菇酪氨酸酶活性的抑制作用;并进一步研究了对B16细胞的增殖形态、黑色素含量和酪氨酸酶活性的影响。结果表明,蜂花粉中游离态和结合态的总酚含量分别为23.36和1.47 mg GAE/g干重(DW),总黄酮含量为19.12和2.42 mg RE/g DW。酚酸类物质大多以游离态形式存在,富含槲皮素和芦丁,而结合态中鞣花酸和3,4-二甲氧基苯甲酸含量较高;游离态和结合态多酚在三种模型中均显示较好的抗氧化活性;抑制蘑菇酪氨酸酶活性IC50分别为22.26和26.34μg/m L,显著高于Vc;一定程度上影响了B16细胞的增殖和形态,同时显著降低细胞内相对黑色素含量和酪氨酸酶活性。玫瑰蜂花粉中不同形态多酚的活性与其酚酸的含量和组成有直接的关系。     

胡麻粕多酚对肠癌细胞凋亡的促进作用

为了探究胡麻粕多酚的肿瘤细胞抑制活性,本研究以胡麻粕为原材料,采用超声提取法和福林-酚法提取并检测提取物中的多酚质量浓度;利用细胞克隆等实验评价胡麻粕多酚对结肠癌以及正常肠上皮细胞增殖的抑制效应;借助流式细胞术和蛋白免疫印迹技术检测胡麻粕多酚对肠癌细胞凋亡的调控;并检测胞内活性氧（reactive oxygen species,ROS）水平以分析胡麻粕多酚对结肠癌细胞内ROS产生的调节作用。结果显示：胡麻粕多酚具有明显的肿瘤细胞抑制活性,并能够促进促凋亡因子Bak和Bax蛋白的表达,抑制抗凋亡因子Bcl-2和Bcl-XL蛋白的表达,且促进细胞色素c的释放;此外,随着胡麻粕多酚质量浓度的增大,DLD1和HCT-116细胞内ROS水平升高。综上所述,胡麻粕多酚能够通过提高肠癌细胞内的ROS水平并促进其进入线粒体凋亡途径从而发挥抗肿瘤作用。     

桑叶浸出液抑制MDA-MB-231细胞增殖和抑制Survivin蛋白表达

为了研究桑叶浸出液对乳腺癌MDA-MB-231细胞增殖和对凋亡抑制蛋白Survivin的作用。本实验采用体外培养MDA-MB-231细胞,倒置显微镜观察桑叶浸出液作用后细胞形态变化;CCK-8法检测桑叶浸出液对MDA-MB-231细胞增殖的影响;流式细胞仪分析桑叶浸出液对MDA-MB-231细胞凋亡及周期的影响;Western Blot印迹法检测桑叶浸出液对凋亡抑制蛋白Survivin表达的影响。结果表明桑叶浸出液会引起MDA-MB-231生长形态的变化,抑制细胞增殖,增加细胞凋亡数量,且在桑叶浸出液作用后MDA-MB-231细胞的G0/G1期细胞明显高于正常组(p<0.05),同时桑叶浸出液降低凋亡抑制蛋白Survivin的表达,且表达量随着桑叶浸出液浓度的升高而降低。研究表明,桑叶浸出液能够抑制MDA-MB-231细胞的增殖,促进细胞凋亡及导致G0/G1期阻滞,同时能够降低凋亡抑制蛋白Survivin的表达。     

米曲霉发酵大米中抗氧化物质对酪氨酸酶的抑制作用

本实验采用两种不同米曲霉菌种(Aspergillus soji,A.orgzae)在35℃和湿度>90%的条件下对大米进行固态发酵6 d,比较发酵大米在发酵过程中活性物质的金属螯合、多酚氧化酶抑制、氧自由基吸收能力及总酚含量的变化。A.orgzae发酵的大米在金属螯合、多酚氧化酶抑制和氧自由基吸收能力上优于A.soji,两者在总酚含量上没有较大差别,且在发酵第4 d时大米的上述四项活性都趋于稳定,故选取A.orgzae发酵4 d的大米探讨其所含活性物质对酪氨酸酶的抑制作用。采用Lineweaver-Burk双倒数法探讨A.orgzae发酵大米中活性物质对蘑菇酪氨酸酶催化L-多巴氧化的抑制作用并推测其抑制机理。同时,虾血淋巴和虾黑变的抑制实验也证明了米曲霉发酵大米对酪氨酸酶的有效抑制作用。     

5种野生浆果的体外抗氧化和抗细胞增殖活性

选取东北大兴安岭地区的特色浆果花楸(Sorbus pohuashanensis H.)、蓝莓(Vaccinium uliginosum L.)、蓝靛果(Lonicera caerulea L.)、沙棘(Hippophae rhamnoides L.)、草莓(Fragaria orientalis Los.)的成熟果实,采用80% 丙酮提取,分别测定多酚、黄酮、花色苷含量,并研究其抗氧化活性和抗细胞增殖活性。结果表明：花楸的多酚和黄酮含量最高;蓝靛果的花色苷含量最高,为(367.5 ± 8.7)g/100g;5 种浆果都具有较好的体外抗氧化活性,花楸显示了最高的抑制癌细胞增殖效应。     

Suppression of the melanogenesis and cellular antioxidant activity in B16 melanoma cells

The results of antioxidant activities by ORAC assay and CAA assay were evaluated for melanogenesis. Although the antioxidant activity by ORAC was not correlated with the melanogenesis, the samples which showed high antioxidant activity by CAA tended to suppress melanogenesis. Caffeic acid and Citrus depressa juice, which demonstrated inhibitory effects on mela‐nogenesis, had high antioxidant activities but no inhibitory effects on tyrosinase activity. In addition, they inhibited the melanogenesis which was increased by inhibition of catalase activity. These results may suggest that antioxidant activity by CAA can contribute to the suppression of melanogenesis in B16 melanoma.     

酸枣叶缩合单宁的分离鉴定及其对黑色素生成的抑制机制

目的:研究酸枣叶缩合单宁的结构特征及其对酪氨酸酶的效应和黑色素生成的抑制机制。方法:利用Sephadex LH-20凝胶柱色谱技术分离制备酸枣叶缩合单宁纯化物,采用硫醇降解结合高效液相色谱-电喷雾电离质谱（Thiolysis-HPLC-ESI-MS）解析酸枣叶缩合单宁的结构单元组成,运用酶动力学、紫外光谱、荧光猝灭等方法系统研究酸枣叶缩合单宁对酪氨酸酶的抑制作用机理,应用CCK-8法、多巴氧化法、NaOH裂解法和实时荧光定量PCR检测酸枣叶缩合单宁对小鼠黑色素瘤细胞（B16F10）的增殖、酪氨酸酶活性、黑色素合成及其相关基因表达水平的影响。结果:构成酸枣叶缩合单宁的主要结构单元是（表）儿茶素和（表）棓儿茶素;酸枣叶缩合单宁具有较强的酪氨酸酶单酚酶和二酚酶抑制活性,是二酚酶可逆的混合型抑制剂;酸枣叶缩合单宁可有效抑制B16F10细胞的增殖、酪氨酸酶活性、黑色素生成量以及酪氨酸酶（TYR）、酪氨酸酶相关蛋白-1（TRP-1）、小眼畸形相关转录因子（MITF）等基因的表达。结论:通过在酶水平和细胞水平的综合分析,阐明酸枣叶缩合单宁对B16F10细胞黑色素合成的分子抑制机制,为后期酸枣叶缩合单宁开发为新的美白化妆品添加剂和果蔬保鲜剂提供理论依据。     

Dual inhibitions of lemon balm (<Emphasis Type="Italic">Melissa officinalis</Emphasis>) ethanolic extract on melanogenesis in B16-F1 murine melanocytes: Inhibition of tyrosinase activity and its gene expression

The effects of wild type and UV-irradiated lemon balm (Melissa officinalis) ethanolic extracts (MOE and UMOE) on melanogenesis in vitro were examined. UMOE showed potent antioxidant activity and significantly inhibited the mushroom and melanocyte tyrosinase activity, and lowered cellular melanin content by 49% at 200 μg/mL in B16-F1 melanocytes. The key gene and protein expression of tyrosinase, tyrosinase-related protein (TRP)-1, and TRP-2 were reduced (−73% for TRP-1 protein at 200 μg/mL UMOE, p<0.05). MOE showed similar results to a slightly lesser degree. We found that myo-inositol, a major compound in lemon balm extracts, significantly reduced cellular melanin synthesis and its effect was greater than arbutin at 1 mM. These suggest that both MOE and UMOE have anti-melanogenic role by both direct inhibition of tyrosinase and down-regulation of gene expressions in melanogenesis. UV-irradiation slightly improved the anti-melanogenic activities. UMOE may be useful as natural anti-melanogenic biomaterials for functional foods and cosmetics.     

Inhibitory effects of chestnut inner skin extracts on melanogenesis

Antioxidant capacities (ABTS radical scavenging assay and ferric reducing/antioxidant power assay), mushroom tyrosinase inhibitory effect, and α-melanocyte stimulating hormone (α-MSH) induced melanogenesis inhibitory effect of 60% methanol extracts and ethylacetate fractions from chestnut inner skin in B16F10 cells were investigated to inspect whitening effect. Above research showed that 60% methanol extracts and ethylacetate fractions from chestnut inner skin resulted in a dose-dependent manner on in vitro antioxidant effects. Especially, the ethylacetate fractions inhibited enzyme activity of mushroom tyrosinases with an IC₅₀ value of 160 μg/mL. Ethylacetate fractions from chestnut inner skin also decreased cellular melanin synthesis in B16F10 melanoma cells. Expression of tyrosinase showed that ethylacetate fractions from chestnut inner skin significantly decreased cellular melanogenesis. Consequently, these results suggest that chestnut inner skin extracts can be considered for a whitening agent of human skin.     

Effects of protein hydrolysate from chicken feather meal on tyrosinase activity and melanin formation in B16F10 murine melanoma cells

Tyrosinase is a copper-containing enzyme that controls mammalian melanogenesis. Tyrosinase inhibitors are important for their potential application in cosmetic products. Chicken feather meal is a rich source of amino acids, which have been linked with tyrosinase inhibition activity. This study investigated the tyrosinase inhibitory properties of protein hydrolysates prepared from chicken feather meal. Protein hydrolysates prepared by pepsin-pancreatin with MW <3 kDa exhibited strong tyrosinase inhibition activity for both monophenolase (IC₅₀ 5.780 ± 0.188 µg/mL) and diphenolase activities (IC₅₀ 0.040 ± 0.024 µg/mL) in a cell-free mushroom tyrosinase system. These samples were uncompetitive inhibitors with Ki values of 18.149 and 27.189 µg/mL in monophenolase and diphenolase activities, respectively. A cell culture model showed that this hydrolysate had the strongest inhibition on the viability of B16F10 cells (IC₅₀ 1.124 ± 0.288 µg/mL) and 0.210 µg/mL of the sample exhibited inhibition of tyrosinase activity by 50.493% and melanin synthesis by 14.680% compared to the control.