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This study examined the inhibition and mechanism of natural product pentagalloyl glucose (PGG) against HepG2 cells and determined the effects of its combination with the clinical chemotherapeutic drug, 5-FU. PGG was found to inhibit the proliferation, migration and invasion of HepG2 cells, induced G1 arrest and apoptosis in both concentration- and time- dependent manners. The combination of PGG and 5-FU had synergistic effects on reversal the aggressive phenotypes of HepG2 cells, increasing the proportion of Bax/Bcl-2, promoting the activation of caspase-9 and caspase-3, and inducing apoptosis. This combination upregulated P27 and cyclin B1, and downregulated cyclin E1, leading to G1 phase arrest. The combination significantly downregulated MDR1 and LRP1, suggesting the potential to reverse the resistance to 5-FU. [ABSTRACT FROM AUTHOR]

It is a crucial step locating the maize plant or even its target location precisely during the intelligent agricultural equipment working in farmland. Therefore, the segmentation of plants from the background image is one of the important research contents of agricultural machine vision. Under the background of significant color difference, the current method can effectively complete maize canopy segmentation and plant location identification. However, under the background of no-significant color difference, there is no robust and high-precision method for maize canopy segmentation and plant location identification. In this study, it was found that the grayscale of maize canopy had gradient distribution trend along the radial direction. The Hue Saturation Value color space and Support Vector Machine method was used to segment 600 maize canopy images, then the polynomial regression method was used to find out the functional relationship between grayscale gradient and canopy diameter. The functional relationship gave identification results of canopy central region under different gray gradient distribution. The result provided a theoretical basis for accurate identification and rapid location of maize plant center at seedling stage, and provided accurate position coordinate and yaw information for field navigation of agricultural intelligent equipment such as plant protection UAV. [ABSTRACT FROM AUTHOR]

Two lignans including a new one, five flavonoids and five coumarins were isolated from the whole plant of Viola philippica (synonymised as Viola yedoensis Makino). The new compound was structurally determined as (7R,8S,8′S) -3,3′-dimethoxy- 4,4′,9-trihydroxy- 7,9′-epoxy-8,8′-lignan 9-O-rutinoside by analysis of its NMR, MS and CD spectroscopic data. The known compounds were characterised by comparing their NMR and MS data with those reported. Among the known compounds, 5-hydroxy-4′-methoxyflavone-7-O- rutinoside, 6,7-di-O-β-D- glucopyranosylesculetin, and 7R,8S-dihydrodehydrodiconiferyl alcohol 4-O-β-D- glucopyranoside were isolated and identified from this genus for the first time. Of these compounds, 5-hydroxy-4′-methoxyflavone-7-O-rutinoside and (7R,8S,8′S) -3,3′-dimethoxy- 4,4′,9-trihydroxy- 7,9′-epoxy-8,8′-lignan 9-O-rutinoside were potently active against α-glucosidase, while the two dimeric coumarins, 5, 5′-bi (6, 7-dihydroxycoumarin) and 6,6′,7,7′-tetrahydroxy-5,8′-bicoumarin potently inhibited HCV protease. [ABSTRACT FROM AUTHOR]

The wood powder and extract ofXanthoceras sorbifoliaare used to treat rheumatism, gout, and other diseases in Mongolian medicine. Information on the pharmacokinetic differences between various forms of the herb drug is needed. EightXanthocerasconstituents were examined simultaneously in rat plasma by ultra liquid chromatography-triple quadrupole mass spectrometry. In vitro experiments were performed to determine the influence of digestive juices on the pharmacokinetic profiles. Epicatechin and dihydromyricetin had higher AUC values in rats that were gavaged withX. sorbifoliaextract versus the pure compounds. The AUC value of epicatechin in rats that were gavaged withX. sorbifoliawood powder was higher than that with the methanol extract. The nonextractable epicatechin polymer in the wood powder could be degraded to epicatechin by gastric juice, consequently elevating the epicatechin levels in blood. [ABSTRACT FROM AUTHOR]

The petals ofCarthamus tinctoriusL. (safflower) is an important traditional medicine for promoting blood circulation and removing blood stasis. The pharmacokinetic properties of multiple safflower constituents have not been fully understood. In the present research, an ultra-high-performance liquid chromatography-triple quadrupole mass method in dynamic multiple reaction monitoring mode was developed and validated to simultaneously quantify in rat plasma of five different characteristic types of safflower constituents, including chalcone, poly-acetylene, glycoside of 6-hydroxykaempferol, etc. All the five constituents, hydroxysafflor yellow A, bidenoside C, 6-hydroxykaempferol-3,6-diglucoside, chlorogenic acid, and p-coumaric acid were detected in rat plasma after oral administration of safflower powder. p-Coumaric acid was the most quickly absorbed one with Tmaxof 0.1 hr. The poly-acetylene constituent, bidenoside C, displayed the largest AUC0-tvalue (2177.796 ng · h/L) followed by hydroxysafflor yellow A (1564.1 ng · h/L). The impressively favorable pharmacokinetic behavior of bidenoside C reported herein for the first time rendered the importance for paying more attention to its role in the in vivo pharmacologic effects of safflower. [ABSTRACT FROM AUTHOR]

Four types of piscidinol A derivatives were synthesized and evaluated their ability to inhibit HIV-1 protease to understand their structure-activity relationships. Of these tirucallane-type triterpene derivatives, an A-secoderivative (1b) moderately inhibited human immunodeficiency virus (HIV) protease (IC5038.2 μM). The 2,2-dimethyl succinic acid (DMS) acylated tirucallane derivatives (4b,6a,and7b, 50 < IC50 < 100 μM) were more inhibitory against HIV-1 PR than the others (PA,2a,4a,4c–4d,5a,6b–6d,and7a, IC50 > 100 μM). These findings indicated that the 2,3-seco-2,3-dioic acid (1b) and DMS-acylated tirucallane-type derivatives preferably inhibited HIV viral protease. [ABSTRACT FROM PUBLISHER]

This study established a new, rapid, and accurate method for bioactive compound screening by the combination of serum pharmacochemistry and serum pharmacology based on a spectrum-effect relationship model. HPLC/ESI-Q-TOF-MS was used for the chemical profiling of samples of dosed plasma, control plasma, and Radix Aconiti Lateralis decoction. A comparison was made of the resulting chemical profiles, which totaled 20 compounds including 16 prototype compounds and 4 metabolites derived from SF decoction that were detected as potential bioactive components. Using MS/MS analysis and accurate molecular weight assessments of TOF, 17 components in 20 potential bioactive compounds were structurally identified. Moreover, the pretreated plasma samples were injected into venous sinus of isolated toad hearts to investigate the cardio-toxicity according to heart ratio (HR) situation and electrocardiograph (ECG) parameters, including PR interval, QRS interval, and QT interval. Finally, 4 compounds in these 20 potential bioactive components that had closest correlation with 4 cardio-toxic experimental indexes respectively were investigated by spectrum-effect relationship model for the first time. The 4 compounds were considered as the real cardio-toxic components. This study proposed a series of potential bioactive components in Radix Aconiti Lateralis and provided a general research pattern to identify the potential bioactivity compounds in Chinese herbs or natural pharmacy. [ABSTRACT FROM AUTHOR]

In a series of studies on the metabolism of iridoid compounds, we investigated the metabolic fate of swertiamarin (1) in Wistar rats. Liquid chromatography/ion trap mass spectrometry detected new nitrogen-containing metabolite gentiandiol (3) in rat plasma. The structure of the metabolite was unequivocally identified by comparing the retention time as well as the mass spectrum with those of authentic compound, which was synthesized from swertiamarin (1). The transformation of swertiamarin to nitrogen-containing metabolite gentiandiol (3) in vivo was verified for the first time. Understanding of this unique metabolic pathway may shed light on clinical efficacy of swertiamarin (1) and will also assist in studies for the metabolism of other natural iridoids in vivo. [ABSTRACT FROM AUTHOR]

Two neuropective compounds were isolated from the rhizomes of Abacopteris penangiana, one was a new flavone and the other was a flavanone. Both compounds were firstly separated from natural plant. The isolation work was guided by the antioxidant activity. Both the compounds showed a significant antioxidant activity in vitro and a protective effect on dopamine-induced neurotoxicity in PC12 cells. [ABSTRACT FROM AUTHOR]

A new compound, named trollioside, together with nine known compounds, proglobeflowery acid, isoswertisin, isoswertiajaponin, cirsimaritin, veratric acid, vitexin, orientin, β-sitosterol and daucosterol, were isolated from the ethanol extract of the dried flowers of Trollius chinensis Bunge. The isolation and structural determination of these compounds are discussed. [ABSTRACT FROM AUTHOR]

Two new glycosyl flavonoids including a glycosyl aurone, together with six known flavonoids were isolated from the roots and rhizomes of Asarum longerhizomatosum. The structures of the two new compounds were elucidated as 4,6,4' -trihydroxy-aurone-4,6-di-O-β-D-glucopyranoside (7, caulesauroneside) and naringenin-7,4' -di-O-β-D-glucopyranoside (8, caulesnarinside). The six known flavonoids were identified as naringenin (1), naringenin-5-O-β-D-glucopyranoside (2), naringenin-7-O-β-D-glucopyranoside (3), chalcononaringenin-2' -O-β-D-glucopyranoside (4), naringenin-5,7-di-O-β-D-glucopyranoside (5), chalcononaringenin-2' ,4' -di-O-β-D-glucopyranoside (6), respectively. This is the first report of the isolation of aurones in the family Aristolochiaceae. [ABSTRACT FROM AUTHOR]