Xiaofan Yuan

Improved growth of Artemisia annua L hairy roots and artemisinin production under red light conditions

Hairy root cultures of Artemisia annua L were cultivated for 30 days under either white, red, blue, yellow or green light. Red light at 660 nm gave the highest biomass of hairy roots (5.73 g dry wt cells l−1 medium) and artemisinin content (31 mg arteminsinin g−1 dry cells) which were, respectively, 17% and 67% higher than those obtained under white light.

Effects of rare earth elements on the growth of Cistanche deserticola cells and the production of phenylethanoid glycosides.

The rare earth elements Nd, La, Ce at proper concentrations had positive effects on the cell growth of Cistanche deserticola and production of phenylethanoid glycosides (PeG). A mixture of rare earth elements (MRE, La(2)O(3):CeO(2):Pr(6)O(11):Sm(2)O(3)=255:175:3:1, mol/mol) showed the most remarkable effects. After 30 days culture, 0.02 mmoll(-1) MRE gave the highest content (20.8%) and production (1.6 gl(-1)) of PeG, which were 104 and 167% higher than those obtained in control (without rare earth elements).

Optimization of ultrasonic circulating extraction of polysaccharides from Asparagus officinalis using response surface methodology

Polysaccharides were extracted from Asparagus officinalis. A novel ultrasonic circulating extraction (UCE) technology was applied for the polysaccharide extraction. Three-factor-three-level Box-Behnken design was employed to optimize ultrasonic power, extraction time and the liquid-solid ratio to obtain a high polysaccharide yield. The optimal extraction conditions were as follows: ultrasonic power was 600 W, extraction time was 46 min, the liquid-solid ratio was 35 mL/g. Under these conditions, the experimental yield of polysaccharides was 3.134%, which was agreed closely to the predicted value. The average molecular weight of A. officinalis polysaccharide was about 6.18×10(4) Da. The polysaccharides were composed of glucose, fucose, arabinose, galactose and rhamnose in a ratio of 2.18:1.86:1.50:0.98:1.53. Compared with hot water extraction (HWE), UCE showed time-saving, higher yield and no influence on the structure of asparagus polysaccharides. The results indicated that ultrasonic circulating extraction technology could be an effective and advisable technique for the large scale production of plant polysaccharides.

Physicochemical characteristics of ultrasonic extracted polysaccharides from cordyceps cephalosporium mycelia.

Ultrasonic extraction (USE) of polysaccharide from cordyceps cephalosporium mycelia was introduced and compared with hot water extraction. Crude polysaccharides were investigated for morphological and thermodynamic properties. Two major fractions (USEP40-1, USEP70-1) were purified and investigated for IR spectra, molecular weights, monosaccharide compositions and antioxidant activities. The results suggested that USE gained higher extraction efficiency due to its intense extraction process. USE caused a more compact arrangement in crude polysaccharides. IR spectra of USEP40-1 and USEP70-1 were different at around 1746 cm(-1). The molecular weights of USEP40-1 and USEP70-1 were 61.4 kDa and 25.1 kDa. USEP40-1 and USEP70-1 were composed of D-mannose, D-glucose, D-galactose, L-rhamnose, and L-arabinose with molar ratio of 11.52:5.54:8.75:2.45:2.59 and 11.50:6.74:5.75:4.46:2.39, respectively. Different ABTS and hydroxyl radical scavenging activities were observed in USEP40-1 and USEP70-1.

Improved cell growth and total flavonoids of Saussurea medusa on solid culture medium supplemented with rare earth elements

Callus cultures of Saussurea medusa were cultivated on solid culture medium supplemented with either Ce3+, La3+, Nd3+ or a mixture of rare earth elements. Ce3+, 0.05 mM, gave the highest biomass (0.53 g dry wt per flask) and total flavonoids (27.5 mg per flask), which were, 70% and 100% higher than those without Ce3+ addition, respectively. Ce3+, 0.01–0.1 mM, or La3+, 0.05 mM, or the mixture of rare earth elements, 0.025–0.1 mM, can substitute for 6-benzyladenine, and 0.025 mM Ce3+ can partly substitute for naphthaleneacetic acid in promoting cell growth and biosynthesis of total flavonoids in S. medusa.

Composition and antioxidant activity of the polysaccharides from cultivated Saussurea involucrata

Polysaccharides from cultivated Saussurea involucrata (CSIP) were purified, two major fractions (CSIP1-2 and CSIP2-3) were investigated for their molecular weights, monosaccharide compositions and in vitro antioxidant activities. The results suggested that the molecular weights of CSIP1-2 and CSIP2-3 were approximately 163.5 kDa and 88.6 kDa, respectively. CSIP1-2 was composed of glucose, galactose, xylose, rhamnose, arabinose and galacturonic acid with a molar ratio of 1.651:0.39:0.062:8.331:1.759:40.426. CSIP2-3 was composed of glucose, galactose, xylose, rhamnose, arabinose and galacturonic acid with a molar ratio of 0.762:0.657:0.112:5.587:0.318:44.655. Different scavenging activities on superoxide radical, DPPH radical and hydroxyl radical were observed in CSIP1-2 and CSIP2-3 at tested concentrations.

Simultaneous analysis of diosgenin and sarsasapogenin in Asparagus officinalis byproduct by thin-layer chromatography

INTRODUCTION Asparagus officinalis L. has several biological activities including antifungal, antiviral and antitumoral activities due to the steroidal saponins. Normally diosgenin and sarsasapogenin are analysed separately by thin-layer chromatography or high-performance liquid chromatography (HPLC-UV or HPLC-ELSD), which is time-consuming and expensive, so we need to find a rapid solution to this problem. OBJECTIVE To develop a sensitive, rapid and validated TLC method for simultaneous detection and quantification of diosgenin and sarsasapogenin. METHODOLOGY Samples were prepared by extraction of A. officinalis with 70% aqueous ethanol to get steroidal saponins, and then hydrolysed using 36  mL 2 m hydrochloric acid for 3  h. The hydrolysis product was extracted with chloroform, and then analysed by TLC, the results of which were verified by HPLC and HPLC-MS. RESULTS The retention factor (R(f)) of diosgenin and sarsasapogenin on TLC plate were 0.49 and 0.6, respectively. After calculation from the regression equation of the standard curve, the contents of diosgenin and sarsasapogenin in the A. officinalis extract were 0.27-0.46 and 0.11-0.32%, respectively. CONCLUSION The study showed that thin-layer chromatography can be applied for the determination of diosgenin and sarsasapogenin in the oldest tissue of A. officinalis, and also can be conducted for screening of sapogenin in other plant or extracts.

Adsorption properties and preparative separation of phenylethanoid glycosides from Cistanche deserticola by use of macroporous resins

A simple and efficient chromatographic method for large-scale preparative separation of phenylethanoid glycosides (mainly contain echinacoside and acteoside) from Cistanche deserticola was developed. The adsorption properties of eight macroporous resins were evaluated. Three selected resins were further screened depending on the adsorption kinetics curves, in which HPD300 resin showed the best separation efficiency. The adsorption isotherm data on HPD300 resin were fitted to the Freundlich equation in certain concentration range. The dynamic adsorption and desorption experiments were carried out on columns packed with HPD300 resin to optimize the separation process. The breakthrough curves showed that acteoside had a higher affinity to the resin than echinacoside. The contents of echinacoside and acteoside in the product increased from 1.79% and 1.43% in the crude extracts to 16.66% and 15.17%, with recovery yields of 80.41% and 90.17%, respectively. The purity of total phenylethanoid glycosides in the product was 76.58%.

Enrichment and separation of chlorogenic acid from the extract of Eupatorium adenophorum Spreng by macroporous resin

A simple and efficient chromatographic method for separation of chlorogenic acid from Eupatorium adenophorum Spreng extract was developed. The adsorption properties of nine macroporous resins were evaluated. NKA-II resin showed much better adsorption/desorption properties. The adsorption of chlorogenic acid on NKA-II resin at 25°C was well fitted to Langmuir isotherm model and pseudo-second-order kinetic model. The dynamic adsorption and desorption experiments were carried out on columns packed with NKA-II resin to optimize the separation process. The content of chlorogenic acid in the product increased to 22.17%, with a recovery yield of 82.41%.

Optimization of cryopreservation of Artemisia annua L. callus.

Cryopreservation of callus tissue of Artimisia annua L. was optimized. Two lines of calli were precultured on MS medium with 5% (v/v) dimethyl sulfoxide, and protected by a cryoprotectant containing 15% (v/v) ethylene glycol, 15% (v/v) dimethyl sulfoxide, 30% (v/v) glycerol and 13.6% (w/v) sucrose. The highest survival rate of callus A201 reached 87% after it was pretreated at 25 °C, cryopreserved by liquid nitrogen, recovered in water bath at 25 °C and reloaded at 25 °C with 34% (w/v) sucrose solution, and that of callus A202 reached 78% after it was treated as callus A201, except pretreated at 35 °C, recovered at 35 °C and reloaded with 47.8% (w/v) sucrose solution.