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Some natural alkaloids from medicinal plants, such as yohimbine and its derivatives, have been reported with adrenoceptor (AR)α2 subtypes inhibiting activity. In trying to address the possible mechanism of the action, a set of homology models of ARα2 was built based on MOE. After that, docking and molecular dynamics methods were used to investigate the binding modes of yohimbine and its 2 derivatives in the active pocket of adrenoceptorα2 subtype A, B, and C. The key interactions between the 3 ligands and the 3 receptors were mapped. Binding mode analysis presents a strong identity in the key residues in each subtype. Only a few differences play the key role in modulating selectivity of yohimbine and its derivatives. These results can guide the design of new selective ARα2 inhibitors.

Some natural products from traditional Chinese medicine (TCM) such as flavones and resveratrol have been reported to have thromboxane A2 receptor (TP) inhibiting activity. We investigated a possible inhibition mechanism by a homology model of TP, which was built based on the crystal structure of squid rhodopsin. After that, docking methods were used to investigate the binding modes of resveratrol and apigenin in the active pocket of TP. Furthermore, a three. dimensional pharmacophore model was generated for screening other potential natural TP inhibitors. The results indicate that resveratrol and apigenin bind to the active site of TP similar to the way that thromboxane A2 binds to Ser201, Leu198, Arg295, and Thr298. The former three key residues can form hydrogen bonds with the inhibitors. The pharmacophore model consisted of seven features and a set of volume spheres, which has been proven to be efficient in identifying compounds with high TP inhibition activity. In this way, a set of potential TP inhibitors were screened from a natural product database. Some of them were reported to have platelet aggregation inhibiting activities. This research indicates that TP could be an important target of TCM drugs with blood circulation activation effects.

The active components in salvia miltiorrhiza bunge (danshen) include danshensu, labiatenic acid, and tanshinone, and they are known to be key compounds for danshen's blood-activating effect in traditional Chinese medicine. Studies show that these compounds have some common scaffolds. A systematic investigation was conducted to locate the targets of these active components among proteins with reported crystal structures. A structural informatics knowledgebase derived from protein structure and ligand-binding mode information was employed in this investigation. Furthermore, docking methods were used to rationally discover the relationship between the scaffold characteristics and the binding ability with the proteins. Results indicate that the active components comprehensively inhibit the metabolic network of adrenaline, which is a strong endogenetic cardiovascular activator. Consequently, adrenaline and its derivatives are accumulated and blood circulation is activated. We propose that key enzymes in the metabolic pathway of adrenaline including phenylethanolamine N-methyltransferase, catechol O-methyltransferase, and monoamine oxidases are targets for the active components in danshen. This research aids in the understanding of the mechanism of danshen's activating blood action.

The new starch was isolated from different Fritillaria TCM ( Fritillaria thunbergii Miq., Fritillaria ussurensis Maxim., Fritillaria pallidifloca Schrenk, Fritillaria cirrhosa D.Don and F. hupehensis Hsiao et K.C. Hsia), and physicochemical properties such as amylose content, moisture content, ash content, morphology, thermal properties and crystallography were investigated. The starch isolated from different Fritillaria showed significant variation in physicochemical properties. The amylose content of these starches ranged from 21.7% to 30.2%, respectively. The size and shape of starch granules separated from Fritillaria differed significantly. The transition temperatures and enthalpy of gelatinization (Δ H gel ) were determined using differential scanning calorimetry (DSC). F . cirrhosa starch showed the highest Δ H gel value (9.18 J/g) and the lowest transition temperature while F. hupehensis starch showed the lowest values (5.90 J/g) and the highest transition temperature. All the five Fritillaria starches showed a typical B-type pattern and degree of crystallinity between 43.8% and 52.3%.

To fully understand the medicinal plant, Fritillaria, and its species, we investigated the physical properties of starch contained in four Fritillaria species, Fritillaria thunbergii Miq., Fritillaria ussurensis Maxim., Fritillaria pallidifloca Schrenk and Fritillaria cirrhosa D.Don, by means of various analytical methods. The crystal type of the former three kinds of Fritillaria starches was in characteristic B-type, which was in agreement with the crystal type of potato starch. However, the cirrhosa F. starch showed a typical CB-type pattern. The degrees of crystallining of the four Fritillaria starches were about 43.2%, 40.5%, 44.8% and 41.8%, corresponding to thunbergii F. starch, ussurensis F. starch, pallidifloca F. starch and cirrhosa F. starch. The granule sizes of the former two Fritillaria starches ranged from 5 to 40 µm, and were cycloidal or elliptic-shaped. However, the latter two Fritillaria starch granules had granule sizes ranging from 5 to 50 µm, and the granule shape varied from oval to irregular or cuboidal. From the thermogravimetric analysis, it was concluded that the thermal stabilities of the four kinds of starch differed from each other, due to their different structures.

The starches separated from four different Dioscorea opposita Thunb. cultivars were investigated for morphological, thermal, crystal, and physicochemical properties, such as amylose content, swelling power, solubility and water-binding capacity properties. Amylose content of D. oppositastarches from different cultivars ranged from 20.74% to 25.94%. The shape of starch granules separated from different D. opposita Thunb. cultivars varied from round to oval or elliptic. The mean particle diameter of starches ranged from 23.39 to 26.87 μm. The transition temperatures (To, Tp and Tc) and enthalpy of gelatinization (ΔHgel) were determined using differential scanning calorimetry (DSC). To, Tp and Tc varied from 73.6 to 74.8, 78.8 to 81.0, and 83.3 to 87.2 °C, respectively. D. opposita cv. Jinchengerhao starch showed the highest ΔHgel values (12.48 J/g) while D. opposita cv. Baiyu starch showed the lowest values (8.413 J/g). The crystal type of starches separated from different D. opposita cultivars was a typical CB-type pattern. The degrees of crystallinity of the four D. opposita cultivars starches were about 50.52%, 32.99%, 33.57% and 36.16%, respectively.

The physicochemical, morphological, thermal and crystal properties of the starches separated from four different Dioscorea opposita Thunb. cultivars (Taigu, Ribenbai, Wenxi and Zhongbowen) were studied. Amylose contents of D. opposita Thunb. starches from different cultivars ranged from 21.17% to 25.00%. The shape of starch granules separated from different D. opposita Thunb. cultivars varied from round or oval to elliptic or caky. The surface of the starch granules appeared to be smooth without any fissures. The average particle diameter of starches from different D. opposita Thunb. cultivars ranged from 25.90 to 28.06 μm. The transition temperatures (To, Tp and Tc) and enthalpy of gelatinization (ΔHgel) were determined using differential scanning calorimetry (DSC). To, Tp, Tc and ΔHgel of D. opposita Thunb. starches ranged from 73.1 to 73.9, 77.6 to 80.4, 82.1 to 85.9 °C and 6.548 to 12.13 J/g, respectively. The crystal type of starches separated from different D. opposita Thunb. cultivars was a typical C-type pattern. The relative degree of crystallinity of the four D. opposita Thunb. cultivars starches were about 38.79%, 39.88%, 41.67% and 49.03%, respectively.

A novel flavonol glycoside named wanepimedoside A was isolated from the whole plant of Epimedium wanshanense, along with fifteen known flavonoids, anhydroicaritin, desmethylanhydroicaritin, icarisid I and II, quercetin, ikarisoside A and B, sagittatoside B, 2"-O-rhamnosylicarisid II, icariin, 2"-O-rhamnosylikarisoside A, epimedin B, epimedin C, and diphylloside A and B.

Seventeen oleanane-type saponins were isolated from the root bark of Aralia armata . Their structures were elucidated by chemical and spectral evidence. Except for oleanolic acid 28-O-β- d -glucopyranoside all the saponins have a glucuronopyranosyl residue at the C-3 position of the aglycones and other sugar substitutes bind to glucuronic acid at positions C-3 and/or C-4. A comparison of saponin constituents of this plant with other araliaceous plants is provided.

The starches separated from two different Dioscorea opposita Thunb. cultivars were investigated for morphological, thermal and crystal properties. The shape of starch granules separated from different D. opposita Thunb. cultivars varied from round to oval or irregular. The surface of the starch granules appeared to be smooth without any fissures. The average particle diameter of starches from different D. opposita Thunb. cultivars was 40.3 and 38.7mum for D. 47 and D. SXY starch, respectively. The transition temperatures (T(o), T(p) and T(c)) and enthalpy of gelatinization (DeltaH(gel)) were determined using differential scanning calorimetry (DSC). The D. SXY starch showed the lower T(o) (74.2 degrees C) and the broader R (12.4). T(p) and T(c) of starch from D. 47 were higher than that of D. SXY starch. DeltaH(gel) values (11.37J/g) of D. 47 was higher than that of D. SXY starch (10.78J/g). The crystal type of starches separated from two different D. opposita cultivars was a typical C-type pattern. The degree of crystallinity of two D. opposita cultivars starches was about 45.9% and 31.5%, respectively.

A new flavone glycoside, identified as kaempferol 3- O -[3′″-acetyl-α- l -arabinopyranosyl-(1′″–6″)]-β- d -glucopyranoside ( 1 ), has been isolated from the aerial part of Thalictrum atriplex .

Background: Radix Paeoniae Alba, Radix Paeoniae Rubra, and Cortex Moutan are important Chinese herbs. Their bioactivities and efficacies are similar. However, they have different superior benefits clinically; so, a comprehensive investigation of the chemical difference is necessary and is of great importance for more reasonable quality assessment and proper clinical application of these three herbal medicines. Objective: To establish a high-performance liquid chromatography (HPLC) fingerprint method for the quality control of Radix Paeonia Alba, Radix Paeonia Rubra, and Cortex Moutan, and to compare their main constituents. Materials and Methods: The separations of Radix Paeoniae Alba, Radix Paeoniae Rubra, and Cortex Moutan was carried out, respectively, through a gradient elution using a monolithic column and a mobile phase consisting of water (containing 0.1% formic acid) and acetonitrile (containing 0.1% formic acid) at a flow rate of 5.0 ml/min. The detection wavelength was set at 230 nm. The data calculation was performed with CHROMAP v1.51 and Statistical Package for the Social Sciences (SPSS) 18.0 software for principal component analysis. Results: A rapid separation method based on high-performance liquid chromatography with diode-array detection (HPLC-DAD) with monolithic columns and a fingerprint analysis method was established. Fifteen Radix Paeonia Alba, 45 Radix Paeonia Rubra, and 21 Cortex Moutan samples were analyzed and 11 chromatographic peaks were identified. Differences of chromatographic peaks among these three herbal medicines in chemical compositions were revealed. Conclusion: The separation and analysis method are fast and simple, which can be used for chemical fingerprint comparison of Radix Paeonia Alba, Radix Paeonia Rubra, and Cortex Moutan. The results for the evaluation of the three medicines could provide experimental evidence for chemical affinity.

Since green tea has been reported to exhibit the effects of promoting antitumour activity, antimutagenicty and antioxidation, we have analyzed its active components by high performance thin layer chromatography (HPTLC). It is suggested that drinking green tea at normal levels daily is not sufficient to produce pharmacological actions.

This paper deals with an interdisciplinary study covering historic, botanical, phytochemical, pharmacological and clinical aspects of rhubarb and related species, to lay stress on the correlation between plant phylogeny, chemical constituents and purgative activity. It was found that the official rhubarbs were exclusively restricted in the Sect. Palmata, e.g. Rheum palmatum, R. palmatum var. tanguticum, R. officinale; the following criteria may serve as their standard, viz., the presence of sennoside derivatives and rhein, the occurrence of the reduced form of rhein and aloe-emodin, the leaves with any kind of palmate incision. Comprehensive multivariate analyses showed that there is a very close relationship between the leaf incision, existence of sennosides or rhein and purgative activity.

The chemical constituents of Beesia calthaefolia and Souliea vaginata were examined. From the rhizomes of B. calthaefolia, four new 9,19-cyclolanostanol xylosides, named beesiosides I–IV were isolated. Beesiosides 111 and IV were found also in the rhizomes of S. vaginata. On the basis of chemical and spectral evidence the structure of beesioside III was established as 15α-acetoxy-20ξ1,24ξ2-epoxy-9,19-cyclolanostane-3β,12β,16β,25-tetraol-3-O-β- D -xylopyranoside.

Przewalskia tangutica Maxim. (Solanaceae), a plant of Tibetan traditional medicine, was investigated. Contents of tropine, cuscohygrine, (-)-6beta-hydroxyhyoscyamine, hyoscyamine, apoatropine, scopolamine and daturamine were determined (Table I). The roots of this plant showed high contents of both hyoscyamine (major constituent) and total alkaloids, amounting to 1.67-3.82% and 2.06-4.01%, respectively. This plant and the crude drugs prepared from it are noteworthy as new sources of tropane alkaloids. The occurrence of tropane alkaloids in solanaceous plants of China is discussed briefly (Table II).

Six compounds have been isolated and characterized from the rhizomes of Antenoron neofiliforme: procyanidin B2-3'-0-gallate, procyanidine B2, (-)-epicatechin-3-0-gallate, (-)-epicatechin, (+)-catechin and gallic acid