Background: Thymus is a widely used medicinal plant in food and pharmaceutical industries. Among different species of Thymus, T. vulgaris is used more than other species in therapeutic dosage forms. Objective: This study was conducted to differentiate various Thymus species by TLC fingerprint. Methods: In order to identify and differentiate various species of Thymus, TLC fingerprints of essential oil, dichloromethane, ethylacetate and n-butanol extracts of four available species named  T. vulgaris, T. pubescens, T. citriodorus and T. daenensis were obtained and compared with each other. Results: The results showed that the TLC chromatograms of essential oil and n-butanol extract can not be used as differential identification for the above-mentioned species; while the ethylacetate and dichloromethane extracts are more reliable to be used for TLC fingerprints. TLC chromatogram of ethylacetate extract is specific for identification of T. pubescens and T. vulgaris while T. citriodorus and T. daenensis can be best identified by their TLC fingerprints obtained from dichloromethane extract.Conclusion: For best differentiation of various Thymus species, different extracts of the plants should be used.

Saffron dark- red stigmata of Crocus sativus. L flowers is a very high value material due to its applications, mainly those to provide color and flavor to foods. Dietary factors play a significant role in both cancer promotion and prevention. Carotenoieds are one of the most common dietary compounds that have been studied as cancer- preventive agents. Recently extracts from natural products and saffron ave also been shown to exhibit anticancer activity. The main pigments of saffron are mono - and di-glycosyle esters of the polyene dicarboxylic acid crocetin, where D-glycose and D- gentobiose occurs as carbohydrate residues. For the extracton of saffron 20gr was successively and exhausively extracted with light petroleum, diethyl ether and methanol in a Soxhlet extractor in the dark. The methanol extract contained the glycosede carotenoids of saffron. Separation of the constituents were achieved by silica gel TLC using different solvent (mobile phase) system. The TLC method was time consuming and also gave an over estimation of the colour principles.

Spirulina platensis is a blue-green microalga with high level of bioactive compounds and high protein content. This study aimed to evaluate the presence and types of phenolic compounds as well as ascorbic acid using two methods of Chromatography, TLC and HPLC in Spirulina. In this study, total phenolic compounds were measured by spectrophotometric method. Then, the presence of 14 phenolic compounds and the percentage of these compounds in total phenolic compounds were investigated using thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The results showed that the use of water as a solvent increased significantly the amount of phenolic compound extracted compare the use of methanol. Total phenol content in aqueous extract was 150. 5 ± 0. 41 mg and methanolic extract was 32. 8 ± 0. 47 mg equivalent to Gallic acid in gram of Spirulina. The presence of 10 phenolic compounds of 14 standard phenolic compounds; Curcumin, Ascorbic acid, Tannic acid, Salicylic acid, Ellagic acid, Gallic acid, Catechin, Quercetin, Vanillin, and Benzoic acid was confirmed in Spirulina. The highest amount of existing phenolic compound was related to curcumin with 30%; as well as, the presence of ascorbic acid was confirmed as 20. 3%. The presence of high levels of phenolic compounds, particularly the high percentage of curcumin and ascorbic acid as strong antioxidants in Spirulina, increases the nutritional value of this microalgae, which has been introduced by the USA Food and Drug Administration as a superfood.

Background: The residuals of lindane insecticide are widely used at rice fields to control pests such as Ephydra spp and Gryllotalpa gryllotaipa. Objective: To determine the residuals of lindane insecticide in rice surface layers of Ramsar city. Methods: This investigation is implemented on 477 samples of soil prepared from the ground depths of 5 to 30 cm in three selected fields in Ramsar using TLC method from 1997 to 1998. Findings: The findings indicated that 8 months after spraying time, lindane concentration at 5 cm depth in some areas was evaluated to be ground 0.09 ppm. Also in the same areas, lindane concentration at 30 cm depth was 0.65 and 0.09 ppm on the first week and 14 months following the poison spraying time respectively. Conclusion: The study revealed a direct relationship between lindane residuals and environmental factors such as precipitation rate, PH and temperature

Hair dyes contain strong allergens and are widely available. Correct labeling is a necessity in order to provide information about the contents, aromatic amines of color precursor are commonly derived from phenylene amine sulfuric acid or para phenylene diamine sulfuric acid. More study in hair dye precursor showed the toxicity behavior and carcinogenesis by contact with aminophenols and 1-4 benzodiazines. The aim of this study was to identify 6 aromatic amines used in commercial hair dye substances by 4 developing solvents and 2 indicator sprays, using a thin layer chromatography (TLC) method. The aromatic amines substances were identified by comparing the Rf values and colors between samples and reference substances. The results showed that each sample contains 3-5 aromatic amines. The superiority of this method in the present study was compared with high performance liquid chromatography (HPLC) and four laboratories participated in the validation and the results showed good interlaboratory reproducibility. J. Color Sci. Tech. 12(2018), 125-133© . Institute for Color Science and Technology.