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1.
Abstract

A flavonoid enriched extract (FE) was obtained from grape peels, and in vitro SPF, antioxidant activity, and effects on cell viability of this extract were tested with the intent to develop a cosmetic product. A formulation was developed with the FE, and the stability of this mixture was evaluated in terms of pH, density, viscosity, and SPF (90-days). FE showed no cytotoxicity to human keratinocytes and an in vitro SPF of 18.56 (UV-spectrophotometry). Further, FE showed a UVA protection factor of 3.17?±?0.2, a critical wavelength of 318.0?±?0.1 and a UVA/UVB of 0.9. Antioxidant activity assays resulted in 92.08% and 86.85% of activity against DPPH and ABTS (IC50 = 296.90?±?1.2?µg/mL and 643.13?±?0.9?µg/mL), respectively. Finally, SPF of formulation with FE was 12.45. Results from the in vitro SPF and product stability tests (especially storage under refrigeration), indicate that FE is a promising compound for use as an innovative sunscreen formulation.  相似文献   

2.
Abstract

The extraction conditions and chromatographic analysis from seeds of Inga edulis were optimized and provided one anthocyanin from aqueous fraction and a mixture of three anthocyanins from methanolic fraction. The pure anthocyanin obtained was subjected to structural modifications and the products obtained were subjected to chemical and pharmacological assays, as well as quantum chemical calculations based on DFT and TD-DFT methods. Hence, the anthocyanin fractions were evaluated for their chemical-pharmacological potential through chemical and biological assays: antioxidant activity by the DPPH, determination of the Solar Protection Factor (SPF) and cytotoxic activity (hepatocellular carcinoma infected with hepatitis C virus). The results indicated that even the anthocyanin and derivatized compounds having high antioxidant potential showed an SPF lower than six, which is lower than the minimum accepted by current Brazilian legislation. In addition, none of compounds presented significant cytotoxic activity against the tumour cell line studied.  相似文献   

3.
4.
The hydrogen transfer reaction mechanism of the complex of a singlet thiol phosphinidene and a polar molecule hydrogen fluoride (HSP- - - HF) has been investigated at the B3LYP/6-311+G (d,p) level in order to better understand the reactivity of singlet phosphinidene. The results show that the relevant reaction, including step 1 [HSP- - -HF(1) → TS1 (2) → HSPH(F) (3)] and step 2 [HSPH(F) (3) → TS2 (4) → H2SPF (5)], are very different from the reactions of hydroxyl phosphinidene with hydrogen fluoride. Furthermore, theoretical studies on the thermodynamic and kinetic properties of the reaction have been carried out over the temperature range of 200–1200 K using the DFT/B3LYP method, the general statistical thermodynamics, and Eyring transition state theory with Wigner correction, which is used to examine the temperature effects the reaction channel. It is concluded that step 1 has both thermodynamic and kinetic advantages over step 2, and the high temperature is favorable to step 2. Moreover, the order of lgK and lgk for the steps are consistent with the order of their exoergic energies ΔE and barrier height, but the differences of lgK and lgk for the steps decrease with the temperature increases.  相似文献   

5.
6.
Matrix I.R. Investigations of Molecular SPF Molecular SPF is generated at 1050 K under high-vacuum conditions when P(S)FBr2 is passed over silber. After cocondensation of the high-temperature gas mixture with an excess of argon the two stretching vibrations and the deformation mode are observed in the matrix infrared spectrum: v(SP) 720.2 cm?1; v(PF) 791.4 cm?1; δ(SPF) 313.6 cm?1. The normal coordinate analyses shows, that in SPF phosphorus is the central atom. Force constants are compared with those of similar molecules.  相似文献   

7.
The aim of the present study was to carry out stability tests and in vitro sun protection factor (SPF) evaluations of formulations containing free or microencapsulated chemical sun filters to improve their use. To this end, three formulations were developed and subjected to stability studies. The most stable formulation was chosen as a vehicle for free and microencapsulated chemical sun filters, and subjected to further stability studies and in vitro SPF assays. The SPF values were approximately 12 and 11 for formulations containing free and encapsulated sun filters, respectively, and both types were stable under stress. Chemical sun filters can be microencapsulated, which may aid in generating innovative sunscreen formulations.  相似文献   

8.
Polycondensates containing sulfonate groups, referred to as concrete superplasticizers, are widely used in the construction industry. A sulfanilic acid–phenol–formaldehyde polycondensate (SPF) with Mw ≈ 100.000 g · mol–1 was synthesized from sulfanilic acid, phenol and formaldehyde by polycondensation reaction, and its intercalation into hydrocalumite type Layered Double Hydroxide (LDH) was investigated. Preparation was done by rehydration of tricalcium aluminate, a cement constituent, in the presence of the polymer. According to the XRD pattern, SPF was successfully intercalated. A d value of approx. 2.6 nm was found. Elemental composition of the new organo‐mineral phase reveals charge balancing of the cationic LDH main layers by the polycondensate. Thermogravimetry indicates that thermal degradation of intercalated SPF occurs at higher temperature, compared to non‐intercalated SPF. According to SEM imaging, the novel Ca‐Al‐LDH phase exhibits the morphology of intergrown platelets. Ultra‐thin nanosheets (foils) with approx. 50 nm thickness were obtained. The layered structure and d value obtained from diffraction analysis were confirmed by TEM imaging. The new hydride can be used as cement and concrete additive.  相似文献   

9.
Nowadays there are many sun-protection cosmetics incorporating chemical and/or physical UV filters as active ingredients and there are no official methods to determine these kinds of compounds in sunscreen cosmetics. The objective of this work is to estimate TiO2 concentration, without sample preparation, employing a portable energy dispersive X-ray fluorescence (EDXRF), aiming to estimate the sun protection factor (SPF) due to the physical barrier in sunscreen composition, and also identify the metals present in the samples. A portable EDXRF system was used for the analysis of fifteen commercial samples. It was also prepared three formulations estimated in FPS-30 using TiO2 at 5%. Quantification was performed using calibration curves with standards from 1 to 30%. The physical barrier contribution in the SPF, associated to Ti concentration, was determined for all samples. The presence of some elements, like K, Zn, Br and Sr was detected in the sunscreen, identifying chemical elements that were not cited in the formulations. Three commercial samples were analyzed for total SPF determination and the result shows that the measured value is 10% lower than the nominal one.  相似文献   

10.
Copper(II) complexes of the type [Cu(SPF)(Ln)Cl] (where SPF is sparfloxacin and Ln = substituted terpyridines) were synthesized and found to have a distorted octahedral geometry. Superoxide dismutase‐like activity of the complexes was measured using a nitroblue tetrazolium/reduced nicotinamide adenine dinucleotide/phenazine methosulfate system and expressed in terms of the concentration of complex which terminates the formation of formazan by 50% (IC50 value), which was found to range from 0.572 to 1.522 µm . Interactions of the complexes with herring sperm DNA were studied by absorption titration, viscosity measurement and gel electrophoresis under physiological conditions. The antimicrobial efficiency of the complexes was tested against five different microorganisms and showed good biological activity. All the complexes showed good cytotoxic activity, with LC50 values ranging from 4.01 to 9.64 µg ml?1. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

11.
Sedimentation field-flow fractionation–inductively coupled plasma–mass spectrometry (SdFFF-ICP-MS) was successfully applied to investigate particle size distribution of titanium dioxide (TiO2) in sunscreen samples after hexane extraction to remove organic components from the samples. Three brands of sunscreen products of various sun protection factor (SPF) value were used as samples. Different particle size distribution profiles were observed for sunscreen samples of various brands and SPF values; however, the particle size distributions of titanium dioxide in most sunscreen samples investigated in this work were larger than 100 nm. The titanium dioxide concentrations were higher for the products of higher SPF values. By comparing the results obtained from online SdFFF-ICP-MS and those from the off-line ICP-MS determination of titanium after acid digestion, ICP-MS was found to effectively atomize and ionize the titanium dioxide particle without the need for acid digestion of the samples. Therefore, the online coupling between SdFFF and ICP-MS could be effectively used to provide quantitative information of titanium dioxide concentrations across particle size distribution profiles.  相似文献   

12.
Sumaira Khan 《Talanta》2009,80(1):158-220
A separation/preconcentration of aluminum (III) (Al3+) has been developed to overcome the problem of high matrix species, which may interfere with the determination of trace quantity of Al3+ in natural water samples. The separation of Al3+ in water samples was carried out from interfering cations by complexing them with 2-methyle 8-hyroxyquinoline (quinaldine) on activated silica. Whereas the separated trace amounts of Al3+ was preconcentrated by cloud point extraction (CPE), as prior step to its determination by spectrofluorimetry (SPF) and flame atomic absorption spectrometry (FAAS). The Al3+ react with 8-hydroxyquinoline (oxine) and then entrapped in non-ionic surfactant Triton X-114. The main factors affecting CPE efficiency, such as pH of sample solution, concentration of oxine and Triton X-114, equilibration temperature and time period for shaking were investigated in detail. The validity of separation/preconcentration of Al3+ was checked by certified reference material of water (SRM-1643e). After optimization of the complexation and extraction conditions, a preconcentration factor of 20 was obtained for Al3+ in 10 mL of natural water samples. The relative standard deviation for 6 replicates containing 100 μg L−1 of Al3+ was 5.41 and 4.53% for SPF and FAAS, respectively. The proposed method has been applied for determination of trace amount of Al3+ in natural water samples with satisfactory results.  相似文献   

13.
2-Cyano-N-(tetrahydrocarbazole)acetamide (1) was utilized for the synthesis of several new arylazocarbazole derivatives (2a–e). Compound (1) reacted with phenyl isothiocyanate to yield the corresponding non-isolable intermediate (3), which gave, upon treatment with dilute hydrochloric acid, thiocarbamoyl derivative (4). Compound (3) reacted with chloroacetone, chloroacetic acid, chloroacetyl chloride, ethyl bromoacetate, and phenacyl bromide to afford thiazolone derivatives (6), (8), and (10), respectively. Compound (1) was heated in the presence of pyridine and/or hydrazine hydrate and/or isatine to give the corresponding tetrahydrocarbazole derivatives (13), (14), and (18), respectively.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   

14.
Group-theoretical foundations for the concept of mandalas have been formulated algebraically and diagrammatically in order to reinforce the spread of the unit-subduced-cycle-index (USCI) approach (S. Fujita, Symmetry and Combinatorial Enumeration in Chemistry, Springer-Verlag, Berlin-Heidelberg, 1991). Thus, after the introducton of right coset representations (RCR) (H\)G and left coset representations (LCR) G(/H) for the group G and its subgroup H, a regular body of G-symmetry is defined as a diagrammatical expression for a right regular representation (C 1\)G, which is an extreme case of RCRs. The |G| substitution positions of the regular body as a reference are numbered in accord with the numbering of the elements of G and segmented into |G|/|H| of H-segments, which are governed by the RCR (H\)G. By regarding each H-segment as a substitution position, the H-segmented regular body is reduced into a reduced regular body, which can be regarded as a secondary skeleton for generating a molecule. The reference regular body (or H-segmented one) is operated by every symmetry operations of G to generate regular bodies (or H-segmented ones), which are placed on the vertices of a hypothetical regular body of G-symmetry. The resulting diagram (a nested regular body) is called a mandala (or a reduced mandala), which is a diagrammatical expression for specifying the G-symmetry of a molecule. The effect of a K-subduction on the regular bodies of a mandala (or a reduced mandala) results in the K-assemblage of the mandala (or the reduced mandala), where the resulting K-assemblies governed by the LCR G(/K) construct a |G|/|K|-membered orbit, which corresponds to a molecule of K-symmetry. The sphericity of the RCR (or the LCR) is used to characterize symmetrical properties of substitution positions and those of stereoisomers. The fixed-point vector for each mandala (or reduced mandala) in terms of row view and the number of fixed points of K-assembled mandalas (or K-assembled reduced mandalas) in terms of column view are compared to accomplish combinatorial enumeration of stereoisomers. The relationship between a mandala and a reordered multiplication table is discussed.  相似文献   

15.
A facile and fast procedure for synthesis of 3-phenyl-cyclohexane(1′-2)thiazolidin-4-one (1), which underwent condensation with glucose and p-chlorobenzaldehyde to afford 2 and 3, respectively. Compound 3 was used as precursor for the preparation of some fused heterocyclic compounds 4–7. Compound 4 was alkylated using dichloroacetone and chloroacetic acid to afford 8 and 9, respectively. Also, it reacted with acrylonitrile and hydrazine hydrate to afford 10 and 11, respectively. Compound 9 was condensed with p-chlorobenzaldehyde and glucose to afford 12 and 13, respectively. Selected members of the synthesized compounds were screened for antimicrobial activity.  相似文献   

16.
Infrared A radiation (IRA) from solar sunlight contributes to photoaging of human skin, e.g. by upregulating MMP‐1 expression in dermal fibroblasts, indicating the need for photoprotection of human skin against IRA. Up to now, however, there has been no controlled study to show that effective protection of human skin against IRA radiation is possible. Here, we have conducted a randomized, controlled, double‐blinded prospective study in 30 healthy volunteers to assess the capacity of an SPF 30 sunscreen versus the same sunscreen supplemented with an antioxidant cocktail containing grape seed extract, vitamin E, ubiquinone and vitamin C to protect human skin against IRA radiation‐induced MMP‐1 upregulation. As expected, exposure to IRA radiation significantly upregulated MMP‐1 expression, as compared to unirradiated skin, and this response was significantly reduced, if the SPF30 sunscreen plus the antioxidant cocktail had been applied prior to IRA radiation. In contrast, treatment of human skin with the SPF30 sunscreen alone did not provide significant protection. These results indicate that topically applied antioxidants effectively protect human skin against IRA radiation and that regular sunscreens need to be supplemented with specific antioxidants in order to achieve IRA photoprotection.  相似文献   

17.
Abstract

Alkylation of 4-anilino-5-phenyl-4H-1,2,4-triazole-3-thiol (1) with some halo compounds yielded the corresponding sulfides 2af. Some sulfides 2e,f were cyclized to give triazolothiadiazines 3 and 4. Triazolothiadiazoles 5 and 6 were prepared through the reaction of compound 1 with carbon disulfide or ethyl orthoformate, respectively. Treatment of compound 1 with ethyl chloroformate or phenyl isothiocyanate yielded triazolo-thiadiazole and triazole 9 and 10, respectively. Reaction of compound 1 with Lawesson's reagent gave triazolothiadiazaphosphole derivative 11. Also, compound 1 underwent cyclocondensation reactions with some bidentate reagents to give triazolothiazines 4, 12, and 13. Triazolo-thiazepines and triaziepine 1416 were synthesized via the reaction of compound 1 with β-ketoesters or ethyl cyanoacetate. Tricyclic systems 19 and 20 were prepared through the reaction of compound 4 with the appropriate reagent. Some synthesized compounds were tested for antibacterial activity.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.  相似文献   

18.
Abstract

The decomposition of 2-chloroethyltrichlorosilane (1) to ethylene-tetrachlorosilane (2), hydrogen chloride-ethylenetrichlorosilane (3), and ethylenechloride-trichlorosilane (4) was investigated using ab initio Molecular Orbital (MO) and Density Functional Theory (DFT). Study on the HF/6-31G level of theory revealed that the required energy for the decomposition of compound 1 to 2, 3, and 4 is 59.86, 101.13, and 63.29 kcal mol?, respectively. MP2/6-31G*//HF/6-31G* calculated barrier height for the decomposition of compound 1 to 2, 3, and 4 is 60.59, 94.04, and 66.91 kcal mol?1, respectively. Also, B3LYP/6-31G*//HF/6-31G* results indicate that the barrier height for the decomposition of compound 1 to 2, 3, and 4 is 51.71, 85.38, and 53.74 kcal mol?1, respectively. Among the three methods, which have been used to calculate the barrier height of the decomposition of compound 1 to 2–4, B3LYP/6-31G**//HF/6-31G** is in good agreement with the reported experimental data. Contrary to the previously evaluated experimental values for the decomposition of compoun 1 to 3 and 4, all three methods predict a higher energy barrier for these reactions.  相似文献   

19.
《Arabian Journal of Chemistry》2020,13(12):8888-8897
The species Andrographis paniculata L. Ness, family Acanthaceae grows in many parts in the island of Java in Indonesia. In this research, new potentials of photoprotective agents from A. paniculata plant extracts, along with their characteristics, were investigated. The phytochemical test, infrared analysis, ultraviolet characterization, fluorescence identification, flavonoid content by thin layer chromatography, high performance liquid chromatography-mass spectrometry (LCMS/MS) and photoprotective analysis were performed in the extracts. The new potentials of A. paniculata plant extracts were studied at various concentrations of extracts and shown by the value of the sun protection factor (SPF). Based on phytochemical test, A. paniculata plant extracts contained flavonoids, alkaloids, tannins, triterpenoids and polyphenols. A. paniculata plant extracts have 2 maximum wavelengths at 230 nm and 362 nm. The excitation peak at 300 nm (552.11 a.u) and the emission peak at 605 nm (516.02 a.u). The flavonoid content of the extracts was 0.022 µg/mL quercetin with Rf value of 0.61. The chromatogram of the LCMS/MS is similar to quercetin-3-glycoside standard at a retention time of 2.77. The photoprotective activity of A. paniculata plant extracts had ≥ 15 SPF. Its shows the possibility to use this extract as photoprotective agent in pharmaceutical preparations.  相似文献   

20.
A series of salicylidenimine functionalized p-tert-butylcalix[n]arene-core dendrimers 7ab were synthesized in higher yields by divergent method from the corresponding ethyl p-butylcalix[n]arylacetates 2ab (n = 6, 8). 2ab were first treated with excess of 1,6-diaminohexane to give amide derivatives with free amine terminal groups 3ab, which in turn reacted with salicylaldehyde in alcohol to yield the first generation of Schiff bases 4ab. 3ab reacted with ethyl acrylate, ammonolized with 1,6-diaminohexane and condonsated with salicylaldehyde successfully to give the second generation of Schiff bases 7ab. The extraction and binding properties of the dentritic Schiff bases 4ab and 7ab for several kinds of metal ions were studied with UV–Vis spectroscopy and atomic absorption spectroscopy. In which they showed a great affinity for soft Cu2 +  ions and formed 1:1 or 1:2 stoichiometric complexes.  相似文献   

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