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Tomato spotted wilt virus is a single-stranded RNA virus and causes a serious plant disease. Its horizontal transmission depends on some thrips species including Frankliniella occidentalis. Its genome encodes a nonstructural protein, nonstructural (NSs), which acts as a silencing suppressor and plays a crucial role in the pathogenicity by defending antiviral immunity using RNA interference (RNAi) in plant hosts. However, its physiological function as a silencing suppressor was not well clarified in insect vectors. This study assessed any change of RNAi efficiencies in two other insect systems by NSs expression. To this end, the gene was cloned into a eukaryotic expression vector and transiently expressed in two different insect species via in vivo transient expression (IVTE). After feeding the recombinant construct to non-viruliferous F. occidentalis, NSs expression was observed for over 2 days in the thrips. Under this expression of NSs, thrips were rescued from a treatment of a toxic double stranded RNA specific to v-ATPase. Interestingly, the thrips treated with IVTE significantly suppressed the expression of RNAi machinery genes such as SID and Dicer-2. The recombinant vector expressing NSs was injected to a non-vector insect, Spodoptera exigua, larvae. The larvae expressing NSs by the IVTE were highly susceptible to an infection of a RNA virus called iflavirus. These suggest that NSs acts as a silencing suppressor in insects and would be used for a synergist for RNA pathogens to control insect pests.

Gastrodia rhizome, a dried and steamed tuber of Gastrodia elata Blume (Orchidaceae), has been traditionally used in Korea, China and Japan for the treatment of neurological and nervous disorders such as headaches, dizziness, vertigo and convulsive illnesses. The ethyl acetate and water extracts of G. elata stimulated plasmin activity. The active ethyl acetate fraction was subjected to centrifugal partition chromatography (CPC) with a two-phase solvent system, composed of n-hexane-ethyl acetate-methanol-water (3:7:4:6, v/v) followed by semi-preparative HPLC purification to separate active compounds and the water fraction was purified by Diaion HP-20 resin and semi-preparative HPLC. In ethyl acetate extract, 4-hydroxybenzyl alcohol (1), 4-hydroxybenzoic acid (2), 4-hydroxybenzaldehyde (3), 4-ethoxymethylphenol (4), 4,4'-oxybis(methylene)diphenol (5) and 4,4'-methylenediphenol (6) were obtained with high purities. Parishin (7) and parishin B (8) were isolated from water extract. Among isolated compounds, 4-hydroxybenzyl alcohol (1), 4-hydroxybenzaldehyde (3) and 4-ethoxymethylphenol (4) significantly stimulated plasmin activity. Copyright © 2015 John Wiley & Sons, Ltd.

The fruit of Schisandra chinensis is a well-known herbal medicine and dietary supplement due to a variety of biological activities including antihepatotoxic and antihyperlipidemic activities. However, the simultaneous validation methodology and pharmacokinetic investigation of nine lignans of S. chinensis extract in biological samples have not been proved yet. Thus, the present study was undertaken to develop the proper sample preparation method and simultaneous analytical method of schisandrol A, gomisin J, schisandrol B, tigloylgomisin H, angeloylgomisin H, schisandrin A, schisandrin B, gomisin N, and schisandrin C in the hexane-soluble extract of S. chinensis to apply for the pharmacokinetic study in rats. All intra- and interprecisions of nine lignans were below 13.7% and accuracies were 85.1-115% and it is enough to evaluate the pharmacokinetic parameters after both intravenous and oral administration of hexane-soluble extract of S. chinensis to rats.

Gradient HPLC coupled to Diode Array Detector (DAD), MS/MS and NMR was applied to the rapid structure determination of major compounds of methanol extracts from leaves and roots of Petasites japonicus. The relative antioxidant capacities of the compounds were evaluated by an HPLC system with post-column on-line antioxidant detection based on 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid radical scavenging. Six compounds were successfully separated on a reverse-phase C18 column and were identified as 5-caffeoylquinic acid (5-CQA), fukinolic acid (FA), 3,5-di-O-caffeoylquinic acid (3,5-DCQA), quercetin-3-O-(6″-acetyl)-β-glucopyranoside (QAG), 4,5-di-O-caffeoylquinic acid (4,5-DCQA) and kaempferol-3-O-(6″-acetyl)-β-glucopyranoside (KAG) by MS/MS and 1H NMR data. Among these compounds, those containing a caffeoyl moiety (5-CQA, FA, 3,5- and 4,5-DCQA) showed relatively strong radical scavenging capacity, with 3,5-DCQA having the greatest radical scavenging capacity in leaf (23.09% of total antioxidant capacity) and root (26.47%) extracts. The relative radical scavenging portion of QAG was only 3.41% in the leaves and KAG did not show any radical scavenging activity. These results demonstrate that the hyphenated HPLC techniques can be successfully applied to rapidly identify structures and evaluate antioxidant activities without prior purification of compounds from plant tissues of P. japonicus. Copyright © 2011 John Wiley & Sons, Ltd.

The effect of the ethanol extract and active components of the fruit of Schisandra chinensis was evaluated on rabbit penile corpus cavernosum (PCC). PCC, pre-contracted with 10(-5) m phenylephrine (Phe), was treated with extracts of S. chinensis at five different compositions of ethanol and water (95%, 70%, 50%, 30% and ethanol/water [v/v]) and three fractions (0.1, 0.5, 1 and 2 mg/mL). The effect of the extracts and active lignans (schisandrol A and schisandrol B) from S. chinensis on sildenafil citrate pre-incubated PCC was also evaluated. The PCC relaxation induced by the 95% ethanol extraction and the n-hexane fraction was concentration-dependent and the ethanol extract enhanced sildenafil citrate-induced PCC relaxation. The active components of S. chinensis (schisandrol A and schisandrol B) significantly enhanced sildenafil citrate-induced relaxation >2-fold; schisandrol A had the highest relaxant effect on sildenafil citrate pre-incubated PCC. The lignans, schisandrol A and schisandrol B, isolated from the fruits of S. chinensis enhanced sildenafil citrate-induced relaxation and may have synergistic action in patients who do not completely respond to sildenafil.

Introduction – Angelica dahurica (Fisch. Ex hoffm.) Benth. Et Hook. is a perennial herb that grows throughout Korea whose dried roots have been used to treat various diseases in Korean traditional medicine. The root extract contains diverse constituents, and it is necessary to determine the active compounds. Objective – To investigate the nitric oxide (NO) inhibitory activity in a root extract of A. dahurica and identify the most active compounds using LC-NMR-MS. Methodology – In search of the anti-inflammatory constituents of A. dahurica extract, the HPLC-based activity profiling approach was used to investigate the extract's NO inhibitory activity. To directly identify the compounds, a hyphenated LC-NMR-MS technique was applied. Reversed-phase isocratic chromatography was performed using the acetonitrile–water solvent system on a C30 column. The identification of the compounds was based on information from ESI/MS and 1H-NMR. Results – NO inhibitory activities for five main fractions of the extract were evaluated, which were identified by LC-NMR-MS as containing furanocoumarins: byakangelicol, oxypeucedanin, imperatorin, phellopterin and isoimperatorin. Conclusion – The results obtained showed that the anti-inflammatory activities of A. dahurica could be linked to imperatorin and phellopterin. Copyright © 2010 John Wiley & Sons, Ltd.

Flavanone glycosides were successfully separated from the crude extract of Poncirus trifoliata by preparative centrifugal partition chromatography with a two-phase solvent system composed of ethyl acetate-acetonitrile-water (3:2:5, v/v/v). Naringin (50.0 mg), neoponcirin (16.8 mg), and poncirin (71.9 mg) were purified from the 524 mg crude extract in only one step. The purities of the isolated compounds were determined to be over 90% by HPLC analysis and their structures were elucidated by (1)H NMR, (13)C NMR, and ESI-MS.

Preparative centrifugal partition chromatography (CPC) was successfully carried out for the separation of sinomenine from the methanolic extract of Sinomenium acutum stems and rhizomes. The optimum two-phase solvent system of CPC was composed of n-hexane/ethyl acetate/methanol/water at a volume ratio of 1:6:2:8 (v/v/v/v) with 0.1% triethylamine (TEA). Preparative CPC yielded 44.3 mg of sinomenine from 400 mg of MeOH extract with a purity of 96.9%.

Centrifugal partition chromatography was applied to separate arctigenin and matairesinol from Forsythia koreana extract with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (5:5:5:5 v/v). Using this method, arctigenin and matairesinol were successfully separated from partially purified F. koreana extracts in only one step. The purities of isolated compounds were determined to be over 90% by HPLC analysis.