Current Issue : April - June Volume : 2013 Issue Number : 2 Articles : 5 Articles
Excessive melanin biosynthesis leads to skin hyperpigmentation which causes undesirable skin appearance. Our previous studies have shown high tyrosinase inhibitory effect of Termilalia chebula fruits. In the present work, we aimed to separate anti tyrosinase fractions of T. chebula fruits. Total extract of T. chebula was prepared by maceration method with methanol 80% and evaporated in vacuum. Dried extract was partitioned successively with petroleum ether, chloroform, ethyl acetate and methanol. Further fractionation of active fraction (methanolic) was performed by liquid-liquid extraction (LLE) to give 18 fractions. Active fractions identified by bioautography and were subjected for colorimetry method in different concentrations using mushroom tyrosinase and L-tyrosine as substrate. The percentages of inhibition and IC50 values of each sample were determined. Fractions ІV and V separated in ethyl acetate-methanol by LLE method exhibited the greatest percentage of tyrosinase inhibition (80.52±1.8% and 76.81±2.1% respectively) in comparison to kojic acid (81.28±2.2%). The least IC50 values were also due to the fractions of ІV and V (IC50 values of 3.8 and 4.1 µg/ml respectively). Our findings indicated that the fractions of ІV and V have high anti tyrosinase effect which is compareable with kojic acid. Concidering the solvent of these fractions (methanol-ethyl acetate), they belongs to phenolic compounds. Further studies for separation of active compound have being carried out....
Basal cell carcinoma (BCC) is the most common human malignancy. Both epidemiological and direct evidence have established\r\nultraviolet (UV) exposure from the sun as the most important risk factor for BCC development. There has only been one\r\nrandomized and controlled study to examine sunscreen�s role in the prevention of BCC, and no significant protective benefit\r\nwas found. This study did not address four important concepts: sunscreen abuse, sunscreen misuse, sunscreen formulation,\r\nand cumulative UV exposure. Thus, the results of this study are difficult to interpret and extrapolate with real-world sunscreen\r\npractices....
Mercury is considered one of the most toxic elements for plants and animals.\r\nNevertheless, in the Middle East, Asia and Latin America, whitening creams containing\r\nmercury are being manufactured and purchased, despite their obvious health risks. Due to\r\nthe mass distribution of these products, this can be considered a global public health issue.\r\nIn Mexico, these products are widely available in pharmacies, beauty aid and health stores.\r\nThey are used for their skin lightening effects. The aim of this work was to analyze the\r\nmercury content in some cosmetic whitening creams using the cold vapor technique\r\ncoupled with atomic absorption spectrometry (CV-AAS). A total of 16 skin-lightening\r\ncreams from the local market were investigated. No warning information was noted on the\r\npackaging. In 10 of the samples, no mercury was detected. The mercury content in six of\r\nthe samples varied between 878 and 36,000 ppm, despite the fact that the U.S. Food and\r\nDrug Administration (FDA) has determined that the limit for mercury in creams should be\r\nless than 1 ppm. Skin creams containing mercury are still available and commonly used in\r\nMexico and many developing countries, and their contents are poorly controlled....
Ethylhexyl triazone (ET) was separated from other sunscreens such as avobenzone, octocrylene, octyl methoxycinnamate, and\r\ndiethylamino hydroxybenzoyl hexyl benzoate and from parabens by normal-phase HPTLC on silica gel 60 as stationary phase.\r\nTwo mobile phases were particularly effective: (A) cyclohexane-diethyl ether 1 : 1 (v/v) and (B) cyclohexane-diethyl ether-acetone\r\n15 : 1 : 2 (v/v/v) since apart from ET analysis they facilitated separation and quantification of other sunscreens present in the\r\nformulations. Densitometric scanning was performed at 300 nm. Calibration curves for ET were nonlinear (second-degree\r\npolynomials), with R > 0.998. For both mobile phases limits of detection (LOD) were 0.03 and limits of quantification (LOQ)\r\n0.1 �µg spot-1. Both methods were validated....
The objective of this cross-sectional questionnaire study was to assess\r\nassociations of a self-report index of sun protection habit strength with sunscreen use in\r\nsporting environments and outdoor physical activity. Participants (n = 234) in field hockey,\r\nsoccer, tennis and surf sports in Queensland, Australia, completed a self-administered\r\nsurvey on sun protection during organized sport, and during general outdoor physical\r\nactivity during 2005/2006. The sun protection habit strength index was dichotomized into\r\ntwo categories. Multinomial logistic regression analyses assessed the associations of low\r\nversus high sun protection habit strength with three categories of sunscreen use (no or rare use; inadequate use; and adequate use). Compared to participants with low sun protection\r\nhabit strength, those with high sun protection habit strength had significantly greater odds\r\nof any sunscreen use during organized sport and during general outdoor physical activity.\r\nThis association was strongest for adequate sunscreen use in both settings. In conclusion,\r\nthis study suggests that the measure of sun protection habit strength is a potentially useful\r\nassessment tool for future sun protection studies....
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