Li-juan Mei

Learn More
Dynamic microwave-assisted extraction (DMAE) technique was employed for the extraction of polysaccharides from Lycium ruthenicum (LRP). The extracting parameters were optimized by using three-variable-three-level Box-Behnken design and response surface methodology (RSM) based on the single-factor experiments. RSM analysis indicated good correspondence(More)
OBJECTIVE To establish a quantitative method for determination of gallic acid, original catechins, catechins, chlorogenic acid, caffeic acid, syringic acid in Lycium ruthenicum. METHOD The sample was separated on an ODS column (4. 6 mm x 250 mm, 5 pnm), eluted with methanol and water containing 0. 1% acid with detected wavelength at 280 nm, and flow rate(More)
OBJECTIVE The interaction between plant growth promoting rhizobacteria (PGPR) and plants can be unstable, PGPR with PGP activities may be well adapted to particular soil environment. Based on this, we isolated and identified PGPRs from different rhizosphere soils according to their multiple mechanisms. METHODS Preliminary screening of PGPRs under the(More)
Traditional Tibetan medicine is important for discovery of drug precursors. However, information about the chemical composition of traditional Tibetan medicine is very limited due to the lack of appropriate chromatographic purification methods. In the present work, A. kansuensis was taken as an example and a novel two-dimensional reversed-phase/hydrophilic(More)
Plants during their growth may suffer from many biotic and abiotic stresses, resulting in a decrease of biological production. They may also establish some mechanisms to resist or tolerate the stresses under the stimulation or induction by a variety of factors, among which, plant growth-promoting rhizobacteria (PGPR) is an important one. In this paper, the(More)
Traditional Tibetan medicine is important for discovery of drug precursors. However, knowledge of the chemical composition of traditional Tibetan medicines is very limited due to the lack of appropriate chromatographic purification methods. In the present work, Salvia prattii was taken as an example, and an off-line hydrophilic interaction liquid(More)
Asterothamnus centrali-asiaticus, a kind of characteristic shrub abundant in grassland and desert areas, has been used as forage fodder for camels and goats in Central Asia, and this plant also plays a critical role in the maintenance of desert grassland ecosystems as a result of its tolerance to poor soils and sand burial. However, its chemical composition(More)
Determining the content of Ca, Fe, Mn, Zn, Cu and Mg in Potentilla parvifolia Fisch by atomic absorption spectrometry was studied. Recovery and RSD of the method is 98.3%-103.2% and 1.21%-3.01% respectively, and the method is rapid and precise. The order of the content in Potentilla parvifolia Fisch is Mg>Ca>Fe>Mn>Zn>Cu. There is not a relation between(More)
Bioactive equivalent combinatorial components play a critical role in herbal medicines. However, how to discover and enrich them efficiently is a question for herbal pharmaceuticals researchers. In our work, a novel two-dimensional reversed-phase/hydrophilic interaction high-performance liquid chromatography method was established to perform real-time(More)
This study investigated the influence of organic sample solvents on separation efficiency of basic compounds under strong cation exchange (SCX) mode. The mixtures of acidic aqueous solution and organic solvent such as acetonitrile, ethanol, methanol and dimethyl sulfoxide (DMSO) were tested as sample solvents. For later-eluting analytes, the increase of(More)