Schinus terebinthifolius Raddi extract and linoleic acid from Passiflora edulis synergistically decrease melanin synthesis in B16 cells and reconstituted epidermis

Several treatments for skin whitening are available today, but few of them are completely adequate, especially owing to the carcinogenic potential attributed to classical drugs like hydroquinone, arbutin and kojic acid. To provide an alternative and safer technology for whitening, we developed two botanical compounds originated from Brazilian biodiversity, an extract of Schinus terebinthifolius Raddi and a linoleic acid fraction isolated from Passiflora edulis oil. The whitening effect of these compounds was assessed using biochemical assays and in vitro models including cellular assays and equivalent skin. The results showed that S. terebinthifolius Raddi extract is able to reduce the tyrosinase activity in vitro, and the combination of this extract with linoleic acid is able to decrease the level of melanin produced by B16 cells cultured with melanocyte‐stimulating hormone. Furthermore, melanin was also reduced in human reconstituted epidermis (containing melanocytes) treated with the compounds. The combination of the compounds may provide a synergistic positive whitening effect rather than their isolated use. Finally, we demonstrated that the performance of these mixed compounds is comparable to classical molecules used for skin whitening, as kojic acid. This new natural mixture could be considered an alternative therapeutic agent for treating hyperpigmentation and an effective component in whitening cosmetics.     

体外消化对藜蒿叶多酚含量及抗氧化活性的影响

本文研究了藜蒿叶提取物在模拟体外消化过程中酚酸含量、抗氧化活性以及对酪氨酸酶活力抑制率的变化。研究表明,经过模拟体外消化后藜蒿叶提取物中的绿原酸、1,5-双咖啡酰奎宁酸、3,4-双咖啡酰奎宁酸、3,5-双咖啡酰奎宁酸、4,5-双咖啡酰奎宁酸5种酚酸含量均显著性降低。总酚含量和DPPH、FRAP、ABTS抗氧化活性经过模拟体外消化后均显著性增加。消化后粗提物和纯化样总酚含量分别升高了73.57%、23.79%,DPPH抗氧化能力分别增强了36.17%、53.29%,FRAP抗氧化能力分别增强了28.71%、15.45%,ABTS清除自由基能力分别增强了163.67%和49.50%。此外,藜蒿叶粗提物对酪氨酸酶活力的抑制率在体外消化过程中也显著性增加,消化后粗提物的抑制率可达到49.88%。从而可有效抑制黑色素生成,具有较好的美白潜力。因此,藜蒿叶提取物经体外消化后具有较好的抗氧化活性和抑制酪氨酸酶活力的能力,有望应用于美白产品的开发,该研究为藜蒿茎加工副产物-藜蒿叶的开发提供了借鉴。     

辐照红景天乙醇提取物的抗氧化作用及美白作用研究

目的:探讨60Co-γ射线辐照处理对红景天乙醇提取物抗氧化及美白作用的影响。方法:本试验所用红景天经不同剂量(5、10、20、30 kGy)的60Co-γ射线辐照处理后,采用1,1-二苯基-2-三硝基苯肼(DPPH)自由基清除率、2,2'-联氨-(3-乙基苯并噻唑啉-6-磺酸)二氨盐(ABTS)自由基清除率及铁离子还原能力(FRAP)、酪氨酸酶抑制实验、小鼠B16黑色素瘤细胞实验,评价辐照红景天提取物的抗氧化活性及美白活性。结果:与未辐照组相比,辐照组红景天提取物的抗氧化活性及美白活性均增加,其中20 kGy辐照组红景天提取物效果最佳,清除DPPH自由基的IC₅₀值为3.75 μg/mL、清除ABTS自由基的IC₅₀值为44.88 μg/mL、铁离子还原能力FRAP值为(1.90±0.05) mmol/mg、抑制酪氨酸酶的IC₅₀值为244.10 μg/mL、能够有效降低小鼠黑色素瘤细胞中黑色素的合成,并在浓度为0.50%以下时无细胞毒性。结论:20 kGy的60Co-γ射线辐照处理红景天乙醇提取物的抗氧化活性最强,并具有良好的美白功效。     

Studying the anti-tyrosinase effect of Arbutus andrachne L. extracts

Arbutus andrachne L. is widely distributed in Jordan. Tyrosinase is the key enzyme in the biosynthesis of melanin. This preliminary study was carried out to assess the possible anti-tyrosinase activity of A. andrachne extracts. Arbutin, hydroquinone and kojic acid were selected as inhibitor standards. Five different extracts (chloroform, butanol, ethanol, methanol and water) were prepared from A. andrachne stems and their activities were compared with the selected tyrosinase inhibitors. IC₅₀ was measured for both, standard and plant extracts. Among the different extracts, the methanolic extract exhibited the highest anttyrosinase activity with an IC₅₀ value (1 mg mL⁻¹). Furthermore, 9 mg A. andrachne methanolic extract showed 97.49% inhibition of tyrosinase activity. Arbutin, hydroquinone, β-sitosterol and ursolic acid were identified in the different extracts of A. andrachne by thin layer chromatography (TLC) and isolated by preparative TLC from the methanolic and chloroform stem extracts, respectively.     

玫瑰发酵液的抗氧化及美白功效探究

通过对玫瑰发酵液的抗氧化和美白功效及皮肤安全性进行评价,探究美白机理。利用酿酒酵母发酵玫瑰获得玫瑰发酵液,检测其对自由基的清除作用以及对酪氨酸酶活性与黑色素合成的影响,利用基因芯片检测其美白机理,采用人体斑贴试验评估其皮肤安全性。结果表明,玫瑰发酵液具有较强的清除DPPH自由基能力,对细胞外酪氨酸酶活性的抑制作用与浓度呈正比,对B16细胞内酪氨酸酶活性以及黑色素合成都有一定的抑制作用;玫瑰发酵液能够抑制黑色素瘤通路上游的NGF和FGF2基因表达;人体斑贴试验显示玫瑰发酵液未引起阳性刺激反应。玫瑰发酵液具有较高的皮肤安全性,同时具有抗氧化、抑制酪氨酸酶活性与黑色素生成的功效,其通过抑制NGF和FGF2的表达发挥美白作用。     

Resveratrol: an original mechanism on tyrosinase inhibition

This paper forms part of studies searching for new bioactive ingredients for cosmetics, for example, in the whitening agent field. The aim of our work was to present resveratrol as an original substrate for tyrosinase with very promising cosmetic perspectives. This study was based on several spectrophotometric analyses with minor adaptations. These analyses suggested that resveratrol is biotransformed by tyrosinase into an oxydated form, becoming a powerful inhibitor of tyrosinase. Furthermore, we show that resveratrol can be used as an additive compound in whitening cosmetics, particularly with a Morus alba extract. These results may help in understanding tyrosinase active site structure and mechanism.     

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.     

Phenolic tyrosinase inhibitors from the stems of Cudrania cochinchinensis

The phytochemcal profiles of Cudrania cochinchinensis leaf, twig, stem and root were compared by HPLC analysis. It was found that C. cochinchinensis stem extract contained some unknown natural products with potential tyrosinase inhibitory activities. Therefore, the chemical constitutes in extract (95% ethanol) of C. cochinchinensis stem were further investigated in this study. A new racemic mixture, (±)2,3-cis-dihydromorin, and fifteen known phenolic compounds, dihydrokaempferol 7-O-β-d-qlucopyranoside, skimmin, quercetin-7-O-β-d-glucoside, 2,3-dihydroquercetin 7-O-β-d-glucoside, kaempferol-7-O-β-glucopyranoside, quercetin-3,7-di-O-β-d-glucoside, morin-7-O-β-d-glucoside, 1,3,5,8-tetrahydroxyxanthen-9-one, 2,3-trans-dihydromorin, aromadendrin, oxyresveratrol, genistin, protocatechuic acid, kaempferol 3,7-di-O-β-glucopyranoside, and naringenin were isolated. Spectral techniques (MS, (1)H NMR and (13)C NMR) were utilized for their structural identification and their inhibitory activities on mushroom tyrosinase were also evaluated. The results showed that tyrosinase inhibitory activities of (±)2,3-cis-dihydromorin (IC(50) = 31.1 μM), 2,3-trans-dihydromorin (IC(50) = 21.1 μM), and oxyresveratrol (IC(50) = 2.33 μM), were more potent than that of kojic acid (IC(50) = 50.8 μM), a well-known tyrosinase inhibitor, indicating that Cudrania cochinchinensis stem will be a great potential agent for the development of effective natural tyrosinase inhibitors.     

文冠果壳皂苷提取物抑制酪氨酸酶活性的研究

分别采用70％的乙醇溶液、蒸馏水2种浸提液提取文冠果壳中的皂苷,并测定其含量以确定最佳提取溶剂.通过对酪氨酸酶催化L-多巴氧化速率的测定研究了文冠果壳粉的乙醇提取液对体外酪氨酸酶活性的抑制作用.结果表明,皂苷粗提液对酪氨酸酶的抑制率与浓度呈非线性变化,随着浓度的增加,抑制剂对酪氨酸酶活性的抑制率先增加后趋于平稳.当皂苷质量浓度为0.36 mg/mL,抑制率可达到64.6％.通过酶抑制作用的Lineweaver-Burk图,分析结果显示,文冠果壳皂苷粗提液对酪氨酸酶的抑制作用类型为非竞争性抑制.上述研究为进一步开发文冠果壳中的美白成分提供了依据,同时又实现了废物利用,提高了农产品的经济价值.     

Whitening effects of 4-hydroxyphenethyl alcohol isolated from water boiled with Hizikia fusiformis

Isolation of phenolic compounds from water boiled with Hizikia fusiformis and purificartrion of the extracts from solvent fractions was achieved using column chromatography. The simple phenolic compound, 4-hydroxyphenethyl alcohol (4-HPEA) with an elemental composition C₈H₁₀O₂ was identified on the basis of spectroscopic data. The whitening effects of 4-HPEA, inhibitory activity against mushroom tyrosinase, and inhibitory activity against melanin production in B16 melanoma cells were evaluated using an in vitro assay system. The whitening effect of 4-HPEA was also measured using a colorimeter and visual assessment of UVB induced hyperpigmentation of brown guinea pig skin. Topical application of 4-HPEA promoted depigmentation of UVB-induced hyperpigmented spots. 4-HPEA has a potential for use as a safe and effective ingredient for whitening in cosmetic and medical applications.     

Extraction,physicochemical characterisation,and bioactive properties of ink melanin from cuttlefish (Sepia esculenta)

The extracted melanin from Sepia esculenta was characterised by physicochemical properties and biological activities. The yields of melanin were 87.1%, 69.9%, and 62.5% by water extraction, enzymolysis and acidolysis, respectively. The ink melanin contained a characteristic indole structure with irregular spherical structures. Water extraction showed a positive effect on preserving the complete structure of melanin particles based on component analysis, whereas enzymes and acids had destructive effect. Water extraction melanin (WM) exhibited a certain thermal stability and light resistance. WM performed in radical scavenging in a dose-dependent manner. The IC₅₀ of WM for DPPH and ABTS was 99.8 and 104.2 μg mL⁻¹, respectively. WM protected kojic acid and ascorbic acid from light radiation. As the exposure time to light radiation prolonged, the stability of kojic acid and ascorbic acid was preserved. It indicated that melanin might be potentially used as an antioxidant and photo-protectant.     

Utilizing hydroglycolic extract from myrobalan fruits to counteract reactive oxygen species

The hydroglycolic (HG) extract from 70% propylene glycol (PG) extraction of myrobalan fruits showed the most appreciable antioxidant efficiency towards 1,1-diphenyl-2-picrylhydrazyl (DPPH) in comparison to the extracts from 30, 50, 70 and 100% ethyl alcohol (EA), and 30, 50 and 100% PG . Its total polyphenols were also higher than others. The additional analysis of antioxidant power revealed that this HG extract was able to counteract the induced oxidation caused by hydrogen peroxide (H(2) O(2) ) and 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH). The quantification for the antioxidant capacity of the extract showed it was equivalent to 93.78 mg of 6-hydroxy-2,5,7,8-tetramethychroman-2-carboxylic acid (Trolox) g(-1) by 2,2'-azino-bis(3-ethylbenzthiazoline-6-suphonic acid) diammonium (ABTS) assay, and was 140.17 mg ascorbic acid (AA) equivalent g(-1) and 107.50 mg Trolox equivalent g(-1) by photochemiluminescence (PCL) assay. The incorporation of the HG myrobalan extract into lotion and sunscreen lotion rendered these products to provide the similar antioxidant power as the extract alone.     

野木瓜总皂苷提取工艺优化及其美白活性组分筛选

目的:优化野木瓜中总皂苷的提取工艺,并为野木瓜总皂苷活性组分在美白化妆品中的后续开发应用奠定基础。方法:在单因素实验的基础上,以乙醇浓度、液料比、提取温度、提取时间为优化因素,总皂苷得率为评价指标,Box-Behnken法优化野木瓜总皂苷提取工艺;依次用不同极性溶剂对其提取物进行萃取,硅胶柱色谱层析进行分离,获得不同活性组分,MTT法检测B16细胞的增殖抑制能力,多巴氧化法检测酪氨酸酶活性。结果:各因素对野木瓜总皂苷得率影响顺序为:乙醇浓度>提取温度>液料比>提取时间;最佳提取工艺为乙醇浓度79%,液料比25:1 mL/g,提取温度81℃,提取时间89 min,总皂苷平均得率为2.16%;各萃取部位中正丁醇部位对细胞增殖和酪氨酸酶活性抑制效果最好,效果优于对照品熊果苷（P<0.05）,其IC₅₀分别为86.61和69.09 μg/mL;正丁醇部位分离得8个活性组分,其中组分Fr.6对B16细胞增殖和酪氨酸酶活性抑制效果最好,IC₅₀分别为80.93和58.99 μg/mL,且抑制酪氨酸酶活性的效果较分离前的正丁醇部位更好（P<0.05）。结论:本文探讨了野木瓜总皂苷的最佳提取工艺,获得的活性组分Fr.6具有良好的美白活性,在美白化妆品产品开发中具有较好的应用前景。     

响应面优化超声提取甘草渣总黄酮工艺及抗氧化研究

研究超声辅助提取甘草渣中总黄酮的工艺条件,采用响应面分析法对其进行优化,并通过测定甘草渣总黄酮提取液对羟自由基和1,1-二苯基-2-三硝基苯肼(DPPH)自由基的清除能力以及铁还原力,考察了其抗氧化活性。结果表明:超声提取甘草渣中总黄酮的最优工艺条件为:超声时间42 min,提取时间2.5h,提取温度70℃,在该条件下甘草渣总黄酮收率为1.49%。甘草渣中总黄酮具有较好的抗氧化活性,其浓度在0.12 mg/mL^1.2 mg/mL之间时,其清除羟自由基能力、清除DPPH自由基能力和铁还原力均随其浓度的升高而增强。     

5种天然植物提取物抗氧化性和酪氨酸酶抑制作用的比较

本研究检测了5种天然植物提取物体外抗氧化及酪氨酸酶活性抑制作用,并分析其黄酮和总酚含量,探讨提取物美白与抗氧化之间的关联。研究表明通过ABTS+、DPPH+、羟自由基、超氧阴离子自由基的清除能力测定得5种提取物的抗氧化能力强弱顺序虽有所差异,但四种抗氧化方法均表明提取物具有一定的抗氧化能力。同时酪氨酸酶活性抑制检测也表明它们均对酶活有一定抑制作用。5种植物提取物抗氧化及酪氨酸酶活性抑制能力均随样品浓度增加而增大,这些结果提示提取物抗氧化能力与其对酪氨酸酶活抑制作用相关联,可能是与提取物中黄酮和总酚物质有关。当采用ABTS+、DPPH+方法时,5种提取物的抗氧化性与酪氨酸酶抑制作用相关性更大,这可能与黄酮和酚类物质对酪氨酸酶活性抑制机理有关,研究结果可为天然美白植物原料的筛选和研发提供一定理论依据与借鉴。     

铆钉菇D447黑色素高产菌株诱变育种及遗传稳定性研究

为提高铆钉菇（Gomphidius sp.）D447的诱变育种的效率,首先对该菌的孢子最佳活化时间及定向筛选剂曲酸的最优添加量进行了研究,结果表明孢子最佳活化时间为6.0 h,曲酸的最优添加量为0.4%。在此基础上,以紫外线、硫酸二乙酯、氯化锂、5-溴尿嘧啶等诱变剂对D447的活化孢子进行了单一及复合诱变,通过曲酸平板初筛,摇瓶复筛方法,最终获得一株黑色素产量为（2.45±0.16） g/L的诱变株DB-3,较出发菌株D447提高了1.57倍。对突变株进行传代稳定性试验,结果表明诱变株DB-3经斜面传代9代以后,黑色素产量仍较稳定,无明显的回复突变。     

利巴韦林抗酪氨酸酶活性及其在贡梨中的保鲜应用

酪氨酸酶是果蔬褐变和黑色素生物合成过程中的关键酶,酪氨酸酶抑制剂在果蔬保鲜和医药领域具有重要意义。该文首次研究了利巴韦林的抗酪氨酸酶活性、机制及其对贡梨鲜切梨块和梨汁的保鲜效果。酶动力学实验的结果表明,利巴韦林是高效、可逆、竞争型的酪氨酸酶抑制剂,其IC₅₀为(0.3±0.05)mmol/L。荧光淬灭和非辐射能量转移实验的结果表明,利巴韦林可静态淬灭酪氨酸酶的内源荧光,且通过1个结合位点与酪氨酸酶形成“利巴韦林-酶”复合物并导致酶的构象发生改变,这一过程伴随着非辐射能量转移。分子对接的结果表明,利巴韦林可以嵌入到酪氨酸酶的活性口袋并与其B链上的6个氨基酸残基(Lys379、Gln356、Gln307、Asp312、Val313、Asn310)形成氢键。贡梨保鲜实验表明,利巴韦林可以有效减少鲜切梨块的失重率和降低梨汁的褐变度。该研究结果为开发新型的果蔬保鲜剂提供了理论依据和实践基础。     

EFFECT OF KOJIC ACID ON THE OXIDATION OF TRIHYDROXYPHENOLS BY MUSHROOM TYROSINASE1

Kojic acid [5-hydroxy-2-(hydroxymethyl)-4-pyrone] inhibited effectively the rate of pigment formation during the oxidation of pyrogallol, 2, 3,4-THAP (2, 3,4-trihydroxyacetophenone) and 2, 4,5-THBP (2, 4,5-trihydroxybutyrophenone) by tyrosinase. On the other hand, kojic acid had a synergistic effect on the rate of methyl gallate and n-propyl gallate oxidation to pigmented product(s) (λ_max= 360 nm and λ_max= 380 nm, respectively). However, kojic acid inhibited effectively the rate of oxygen uptake when each of the above trihydroxyphenols was oxidized by tyrosinase. These results suggest that kojic acid inhibits tyrosinase per se (probably due to its ability to bind copper at the active site of the enzyme) and that it exerts only an apparent stimulatory effect during the formation of pigmented product (s) from methyl gallate and n-propyl gallate. Proof for the latter was obtained by a time-course experiment of kojic acid addition and examination of the spectra of pigmented product(s) formed in the absence versus presence of kojic acid, which suggested that the o-quinone of n-propyl gallate and the o-quinone of methyl gallate can each convert kojic acid to a yellow product(s) absorbing at the 360–380 nm region.     

Biological activity of rice extract and the inhibition potential of rice extract,rice volatile compounds and their combination against α-glucosidase, α-amylase and tyrosinase

Rice is produced for consumption and traditional medicine. Rice is also used as an ingredient in cosmetic products. In this study, the author investigated the biological activity and inhibition potential against α-glucosidase, α-amylase and tyrosinase activity of rice extract (black rice [BR], red rice [RR] and white rice [WR]), rice volatile compounds, rice extract combined with volatile compounds, rice extract combined with standard inhibitors and volatile compounds combined with standard inhibitors. The results revealed that the free-radical scavenging capacity of rice extract is related to the phenolic content and flavonoids. BR showed the highest potential to inhibit α-glucosidase and α-amylase activity, whereas WR showed the highest potential to inhibit tyrosinase activity. Among rice volatile compounds, vanillin and vanillyl alcohol had the highest inhibition potential against α-glucosidase and α-amylase, respectively, whereas guaiacol had the highest inhibitory activity against tyrosinase. Molecular docking supported by the high binding efficiency was also obtained from vanillin and guaiacol when located at the active site of these enzymes. The combination of RR with acarbose (AB) had the highest inhibition potential and showed a synergic effect on both α-glucosidase and α-amylase. Interestingly, the combination of rice extract (BR, RR and WR) and vanillin and vanillyl alcohol had a synergic effect on α-amylase. Moreover, the combination of WR and vanillyl alcohol had the highest inhibition potential and showed a synergic effect on tyrosinase, whereas rice volatile compounds had a synergic effect on tyrosinase obtained from 2-pentylfuran/kojic acid (KA), vanillin/KA and vanillyl alcohol/KA.