Improved extraction of solanesol from tobacco waste by enzymatic cell wall breaking / 生物工程学报

To improve the extraction of solanesol from tobacco waste, we developed an enzymatic cell wall-breaking process with combined cellulase and ligninase. The effects of reaction time, temperature, pH and enzyme/substrate ratio were determined. The results show that the catalytic effect was better than either single enzyme when the ratio of cellulase to ligninase was 15:1 (U/U). Under the optimized conditions of 175 U/g (enzymes/substrate), tobacco to water 1:5 (W/W), temperature 40 degrees C and pH 6.0, the concentration of solanesol in the solution could reach 0.33 g/L after 8 h. And the average leaching rate reached 96.53% which was 1.68 times of the extraction methods of chemical reflux. It provides new way for the extraction of solanesol from tobacco waste, and worthwhile to be further explored.

Effect and mechanism of total flavonoids of orange peel on rat adjuvant arthritis / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the effect of the total flavonoids of orange peel (TFO) against adjuvant arthritis (AA) and the underlying mechanism.</p><p><b>METHOD</b>AA model was induced in male Wistar (correction of SD) rats by immunization with Freund's complete adjuvant Pad thickness was assayed by caliper. Pathological impairment of ankle joint was analysised by hematoxylin and eosin (H&E) staining. Levels of tumor necrosis factor (TNF)-alpha, Interleukin (IL)-1beta and prostaglandin (PG) E2 in serum was detected by radioimmunoassay method. Cyclooxygenase (COX)-2 expression in synovium tissues was measured by Western blot assay.</p><p><b>RESULT</b>The 75 mg x kg(-1) and 150 mg x kg(-1) TFO treatment obviously decreased the pad thickness and improve the pathological impairment of ankle joint of AA rats. In addition, abnormal elevation of TNF-alpha, IL-1beta and PGE2 in serum and COX-2 expression in synovium tissues of AA rats were markedly repressed by TFO treatment.</p><p><b>CONCLUSION</b>TFO can inhibit the development of AA in rats, and the mechanism were likely due to depressing inflammatory mediators production.</p>

High throughput screening method of identifying D5 receptor agonist from Chinese herbs / 生物医学工程学杂志

D5 receptor is a subtype of dopamine D1-like receptor, and it plays a functional role in many neurological disorders. Some natural compounds from Chinese herbs, which were shown to have the property as that of receptor agonist, might provide a rich source in search of new candidates for therapeutic use. For exploring this possibility, we developed a cell-based high throughput (HTS) D5 receptor assay to screen the herb-based natural compound library established in our centre. The D5 receptor plasmid (hD5R/pcDNA3.1) and reporter gene plasmid (4 x CRE/TK/Luci/pGL3) were co-transfected into HEK293 cell line. After G418 being selected, the monoclonal cell lines bearing hD5R and the reporter gene were established and used for agonist screening. To optimize the assay condition, the effects of some factors such as cell number per well, incubation time, and the doses of SKF38393 (a potent selective partial D1-like agonist) were examined by using forskolin, a positive compound for cAMP response element. The best condition for this HTS assay included: the cell number at 5 x 10(4)/mL, the dose of forskolin at 5-20 micromol/L, the dose of SKF38393 at 100 nmol/L-100 micromol/L, and the agonist incubation time at 6 -8 h. Thereafter, water extracts from more than 200 Chinese herbs in our library were screened and three of these water extracts showed positive activity, with higher or similar activity as SKF38393. In conclusion, we have established a cell-based HTS assay for D5 receptor agonist screening, and by use of this HTS assay, 3 Chinese herbs maybe contain components exhibiting D5 receptor agonist property. This work provides an alternative vision of how to use herb medicines and a way to develop potential drugs for treatment of neurological disorders.