RESUMO
Based on the basic theory of thermodynamics, the thermodynamic parameters and related equations in the process of water adsorption and desorption of Chinese herbal decoction pieces were established, and their water absorption and desorption characteristics were analyzed. The physical significance of the thermodynamic parameters, such as differential adsorption enthalpy, differential adsorption entropy, integral adsorption enthalpy, integral adsorption entropy and the free energy of adsorption, were discussed in this paper to provide theoretical basis for the research on the water adsorption and desorption mechanism, optimum drying process parameters, storage conditions and packaging methods of Chinese herbal decoction pieces.
RESUMO
<p><b>OBJECTIVE</b>In order to obtain functional genes, a normalized stems cDNA library was constructed from medicinal plant Dendrobium officinale.</p><p><b>METHOD</b>SMART (switching mechanism at 5' end of RNA transcript) cDNA synthesis combined with DSN (duplex-specific nuclease) normalization was applied to construct the normalized full-length cDNA library of D. officinale.</p><p><b>RESULT</b>The titer of cDNA library was about 1.3 x 10(6) cfu x mL(-1) and the average insertion size was about 1.5 kb with high recombination rate (93.9%). Random selected 163 positive clones were sequenced at single side. Bio-information analysis indicated that 147 from 150 high-quality unique sequences matched corresponding homologous proteins, and they participated in various biological processes based on GO (gene ontology). There were 8 clones with complete coding sequence, which presumed to be full-length genes.</p><p><b>CONCLUSION</b>These results showed preliminarily that we successfully constructed a normalized full-length cDNA library of D. officinale which could be used to screen the functional genes related to metabolic pathways of medicinal ingredients.</p>