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This study was designed to assess the relationship of dietary and serum beta-carotene to the development of oral lesions in smokeless tobacco users. Eighty eight smokeless tobacco users without oral lesions and 18 with lesions participated in the study. Dietary intake of beta-carotene, personal health habits and selected dietary intake were analyzed by questionnaire. Serum levels were assessed by high pressure liquid chromotography. No correlation between dietary beta-carotene intake and serum beta-carotene levels was observed. Results of t-test analysis indicated no significant difference in the mean serum or dietary intake of beta-carotene between the groups. Mean serum beta-carotene for group-I, users without oral lesions and group-2, users with oral lesions were 12.3 ug/dl(I.02 SE), and 10.6 ug/dl(1.59 SE), respectively. Stepwise regression techniques were employed to assess the influence of selected variables on serum beta-carotene. The effects of smoking, smokeless tobacco exposure, alcohol consumption, and age as well as other dietary indices were evaluated. Age (1.015,p<0.001) was the only factor found to influence serum beta-carotene levels. The small sample size and variability within groups may have decreased the likelihood of observing statistical significance for serum beta-carotene between groups. / Master of Science

No / In this work the chemistry of the lichens Candelaria fibrosa and Pyxine coccifera have been investigated for the first time using FT-Raman spectroscopy with the help of quantum mechanical DFT calculations to support spectral band assignments. The non-destructive spectral vibrational analysis provided evidence for the presence of pulvinic acid derivatives and conjugated polyenes, which probably belong to a carotenoid with characteristic signatures at ca. 1003, 1158 and 1525 cm−1 assigned respectively to δ(C–CH3), ν(C–C) and ν(Cdouble bond; length as m-dashC) modes. The identification of features arising from chiodectonic acid in the Pyxine species and calycin and pulvinic dilactone pigments in C. fibrosa were assisted by the quantum mechanical DFT calculations. Raman spectroscopy can provide important spectroscopic data for the identification of the biomarker spectral signatures nondestructively for these lichen pigments without the need for chemical extraction processes.

No / In this paper, it is demonstrated how Raman spectroscopy can be used to detect different carotenoids as possible biomarkers in various groups of microorganisms. The question which arose from previous studies concerns the level of unambiguity of discriminating carotenoids using common Raman microspectrometers. A series of laboratory-grown microorganisms of different taxonomic affiliation was investigated, such as halophilic heterotrophic bacteria, cyanobacteria, the anoxygenic phototrophs, the non-halophilic heterotrophs as well as eukaryotes (Ochrophyta, Rhodophyta and Chlorophyta). The data presented show that Raman spectroscopy is a suitable tool to assess the presence of carotenoids of these organisms in cultures. Comparison is made with the high-performance liquid chromatography approach of analysing pigments in extracts. Direct measurements on cultures provide fast and reliable identification of the pigments. Some of the carotenoids studied are proposed as tracers for halophiles, in contrast with others which can be considered as biomarkers of other genera. The limits of application of Raman spectroscopy are discussed for a few cases where the current Raman spectroscopic approach does not allow discriminating structurally very similar carotenoids. The database reported can be used for applications in geobiology and exobiology for the detection of pigment signals in natural settings.

No / Chemical investigation of nonindigenous Tubastraea coccinea and T. tagusensis by Raman spectroscopy resulted in the identification of carotenoids and indolic alkaloids. Comparison of Raman data obtained for the in situ and crude extracts has shown the potential of the technique for characterizing samples which are metabolic fingerprints, by means of band analysis. Raman bands at ca. 1520, 1160, and 1005 cm–1 assigned to ν1(C═C), ν2(C—C), and ρ3(C—CH3) modes were attributed to astaxanthin, and the band at 1665 cm–1 could be assigned to the ν(C—N), ν(C—O), and ν(C—C) coupled mode of the iminoimidazolinone from aplysinopsin. The antioxidant activity of the crude extracts has also been demonstrated, suggesting a possible role of these classes of compounds in the studied corals.