[Spectroscopic methods applied to component determination and species identification for coffee].

Spectroscopic analysis was applied to the determination of the nutrient quality of ground, instant and chicory coffees. By using inductively coupled plasma atomic emission spectrometry (ICP-ES), nine mineral elements were determined in solid coffee samples. Caffeine was determined by ultraviolet (UV) spectrometry and organic matter was investigated by Fourier transform infrared (FTIR) spectroscopy. Oxidation-reduction titration was utilized for measuring the oxalate. The differences between ground coffee and instant coffee was identified on the basis of the contents of caffeine, oxalate and mineral elements. Experimental evidence showed that, caffeine in instant coffee was 2-3 times higher than in ground coffee. Oxalate in instant coffee was significantly higher in ground coffee. Mineral elements of Mg, P and Zn in ground coffee is lower than in instant coffee, while Cu is several times higher. The mineral content in chicory coffee is overall lower than the instant coffee. In addition, we determined the content of Ti for different types of coffees, and simultaneously detected the elements of Cu, Ti and Zn in chicory coffee. As a fast detection technique, FTIR spectroscopy has the potential of detecting the differences between ground coffee and instant coffee, and is able to verify the presence of caffeine and oxalate.

The identification and cloning of human M961 full-length cDNA and its splicing isoform / 中国医学科学院学报

<p><b>OBJECTIVE</b>To identify and clone the gene encoding human M96 gene and study its expression spectrum in several blood cell lines.</p><p><b>METHODS</b>According to the sequence of human EST which was highly homologous to the mouse M96 gene, primers used for library screening were synthesized, then the human adult testis and fetal brain cDNA library were screened. The gene was analyzed by making use of BLAST and CLUSTAL W, and its expression spectrum was studied by multiple-cell lines Northern blot analysis. The expression change of M961 in cell differentiation was observed by use of K562 cell line induced by hemin.</p><p><b>RESULTS</b>Two cDNA clones encoding human M96 gene were isolated, identified and named as M961, and M962. They were found to be isoforms of each other. Northern, blot showed that M961 gene was expressed highly in CEM, Hel, Dami and K562 cell lines. However, during K562 cell line differentiation, process the expression of M961 elevated only slightly.</p><p><b>CONCLUSIONS</b>M961 gene was expressed highly in pluripotent cell lines with erythrocytic and megakaryocytic potentials.</p>