Effects of harvesting time and processing on the contents of five alkaloids in the herbaceous stems of Ephedra sinica

In the present study,we studied the changes of the contents of alkaloids in the herbaceous stems of Ephedra sinica during different harvest periods as well as before and after processing.The alkaloid contents of 39 batches of ephedra herb,prepared slices ephedra and honey-fried ephedra,24 batches of ephedra herb with different harvesting periods,which were all collected from cultivation base in Inner Mongolia,and 38 batches of prepared slices ephedra purchased from the market were detected by taking norephedrine(NE),norpseudoephedrine(NPE),ephedrine(E),pseudoephedrine(PE)and methylephedrine(ME)as indicators by using HPLC method.The content of total alkaloid in prepared slices ephedra(1.71%–3.14%)was higher than that in ephedra herb(1.20%–2.53%)and honey-fried ephedra(1.52%–2.99%).Contents of different alkaloids in these three types of samples were significantly different.Prepared slices ephedra and honey-fried ephedra showed significant differences in the contents of NE,NPE and ME(P<0.05),and the contents of E were significantly different between ephedra herb and honey-fried ephedra(P<0.05).The total alkaloid content of ephedra herb was the highest in September(3.10%).Alkaloid contents of prepared slices ephedra collected in the market were uneven and 13%–91%lower than those collected from cultivation base.The results provided a basis for the quality evaluation of ephedra herb and its processed products,and had certain guiding significance for the selection of processed ephedra according to different drug purposes in clinical application.It also provided data support for the harvesting time of ephedra herb.

Synthesis and cytotoxicity of kaempferol derivatives

Abstract： In the present study, we developed a simple approach for the structural modifications ofkaempferol （1）. A new compound, 3,5-dihydroxy-2-（4-hydroxyphenyl）-6,8,8-tris（3-methylbut-2-en-1-yl）-4H-chromene-4,7（SH）-dione （5） together with three known compounds, 8-prenylkaempferol （Z）, 6-prenylkaempferol （3） and 6,8-diprenylkaempferol （4）, were synthesized under different reaction conditions. All of derivatives were synthesized in a structural modification way for the first time. Their structures were primarily elucidated by NMR and MS analyses. Compounds 2, 3 and 5 exhibited prominent cytotoxic activity against MDA-231 （IC50 values were 9.45±0.20 μM, 7.15±0.37 μM and 6.92±0.30 μM, respectively） and MCF-7 （ICso values were 10.08±0.57 0M, 10.04±0.23 μM and 2.15±0.20 μM, respectively） breast cancer cells.

Comparative authentication of crude drugs from subgenus Asarum species in China based on microscopic features

According to the Chinese Pharmacopoeia,the Chinese medicinal material(Asari Radix et Rhizoma)Xixin is derived from the species Asarum heterotropoides var.mandshuricum,A.sieboldii,and A.sieboldii var.seoulense.However,many species of the genus Asarum are labeled as"Xixin","Tu-Xixin",or"Nan-Xixin"for sale in producing areas.To distinguish Chinese Asarum species and to ensure their safety and efficacy,we examined the microscopic characteristics of subg.Asarum plants in China(including subg.Asarum plants in the classification system of Flora Reipublicae Popularis Sinicae and the later published Asarum yunnanense)using a hand microtome and a microscopic digital imaging system based on our previous research.Microscopic features of the blades,petioles,and roots of A.yunnanense were investigated for the first time.Moreover,we compared nine species and one variety of the subg.Asarum(i.e.,A.yunnanense,A.caudigerellum,A.himalaicum,A.pulchellum,A.debile,A.caulescens,A.renicordatum,A.caudigerum,A.caudigerum var.cardiophyllum and A.geophilum)in China based on microscopic characteristics of the blades.Several parameters,such as morphological characteristics and distribution of hairs on both upper and lower leaf epidermises;morphological characteristics of hair cells;anticlinal walls of lower epidermal cells;size relationship between outer periclinal walls and cavity outlines of oil cells on lower leaf epidermis;presence or absence of the irregular cells containing red to brown substances among mesophyll cells;and the diameter of the largest vessels in midribs of the blades,were used for discrimination among species.To the best of our knowledge,we provided the first identification key for the 10 taxa based on blade microscopic characteristics that could be used to distinguish these taxa.Based on the key,23 commercial samples collected from seven provinces of China were authenticated as whole dried herbs of A.himalaicum,A.caudigerellum,A.caudigerum,A.pulchellum and A.caulescens.These findings indicated that microscopic approach and related techniques were convenient and feasible and could be used for the authentication of crude drugs from Chinese subg.Asarum species.