A HPLC-UV method was developed and validated for determination of stemokerrine and oxystemokerrine in Stemona kerrii roots. The chromatographic separation was performed on a Hypersil BDS Cl8-column eluted with methanol: 50 mM ammonium acetate solution using a gradient system with a flow rate of 1 mL/min and detection at 300 nm. Stemokerrine and oxystemokerrine showed a linear relationship within the range of 0.5-100 microg/mL. The method was shown to be precise with a RSD <2%. The average percent recovery of stemokerrine was 101.6% and for oxystemokerrine 99.5%. Two samples of S. kerrii were analyzed and the average contents of stemokerrine and oxystemokerrine were 0.2 and 0.05%, w/w, respectively. The present work will provide a useful standardization method for S. kerrii raw materials for further pharmaceutical development.

Stemona curtisii Hook. F.(Family Stemonaceae), a prominent species distributed in the south and southwest of Thailand, has widely been used as a natural pesticide and as treatment for head lice and skin diseases. This study developed a thin-layer chromatography (TLC)-densitometric method for the simultaneous quantification of major components-stemocurtisine, stemocurtisinol and stemofoline-in the extracts from the roots of S. curtisii collected from 10 locations in Thailand. Components were found in the ranges of 0.0353-0.1949,<0.0121-0.0859 and 0.0733-0.1689 percent dry weight, respectively. The method was validated for linearity, precision, accuracy, robustness, limit of detection and limit of quantitation. The linearity was found over the range of 40-320 ng/spot with a good correlation coefficient (r > 0.9866). Intra-day and inter-day precision showed a relative standard deviation of less than 6%. The accuracy of the method was determined by a recovery study, and the average recoveries were 100.4, 100.2 and 100.3% for stemocurtisine, stemocurtisinol and stemofoline, respectively. The proposed TLC-densitometric method was found to be simple, precise, specific and inexpensive, and can be used simultaneously for the routine quality control of raw materials of S. curtisii roots, extracts and their products, and also other products containing these markers.

Context: Chromolaena odorata (L.) R.M.King & H.Rob.(Asteraceae) or Siam weed has long been used to stop bleeding in Thailand and many countries. Only the aqueous leaf extract was investigated in in vivo and there have been conflicting results of in vitro hemostatic mechanisms of this plant. Objective: The most appropriate C. odorata leaf extract that promoted the highest hemostatic activity and the hemostatic mechanisms of these plant extracts will be investigated. Materials and methods: The lyophilized aqueous leaf extract and alcoholic (50, 70, and 95% ethanol) extracts from the fresh and dried leaves were investigated both in vivo and in vitro. The bleeding time in male Wistar rats was measured to investigate the hemostatic effect. The hemostatic mechanisms were tested using in vitro platelet aggregation and blood coagulation tests in sheep plasma. Results: All extracts displayed significantly reducing bleeding time (<2.5 min) in rats but did not induce platelet aggregation or blood clotting in the in vitro study. The in vitro blood clotting times of all extracts were > 0.6 min. Ethanol extract (70%) from the dried leaves proved to be the extract producing the highest hemostatic activity in vivo with the bleeding time of 1.85 min. Discussion and conclusion: The in vivo study with rats confirmed the significant ability of this plant extract to stop bleeding. However, the sufficient amount of calcium and active compounds which are aggregating and clotting agents to enhance blood coagulation and platelet aggregation in in vitro tests should be further studied.

The activity of an aqueous extract of Prasaplai, a Thai traditional medicine, was studied on the isolated rat uterus in the oestrus stage. The results showed that the extract inhibited the contraction induced by a submaximal dose of acetylcholine (2.04 × 10(-4) mg mL(-1)), oxytocin (1.54 × 10(-4)mg mL(-1)) and prostaglandin E(2)(PGE(2))(6.00 × 10(-4) mg mL(-1)). The inhibition was concentration-dependent and reversible by tissue washing. The IC(50) of Prasaplai extracts expressed as milligram of powdered preparation per millilitre of perfusion solution for acetylcholine, oxytocin and PGE(2) were 11.70, 10.00 and 5.75 mg mL(-1), respectively. These data reveal that Prasaplai has an antispasmodic effect against uterine contraction by different mechanisms and corroborate the traditional use in the treatment of dysmenorrhoea. Oral administration of single dose of the water extract, calculated as powdered Prasaplai up to 20 g kg(-1) in rats, showed no sign and symptom of acute toxicity, and no rat died even at the maximum dose.

INTRODUCTION Stemona spp. have been traditionally used as natural pesticides and medicinal plants. Stemona collinsiae Craib has been of interest for its insecticidal activity, which has been supported by many scientific research studies. The roots contain didehydrostemofoline and stemofoline alkaloids as active components. OBJECTIVE To develop and validate a HPLC method for the quantitative analysis of didehydrostemofoline and stemofoline in S. collinsiae root extracts. METHODOLOGY HPLC was carried out using a Hypersil BDS C(18)-column eluted with methanol:1 m m ammonium acetate (55:45) with a flow rate of 1 mL/min and detection at 295 nm. Method validation was performed to assure its linearity, precision, accuracy and limits of detection and quantitation. RESULTS Didehydrostemofoline and stemofoline showed a linear relationship within the range of 0.5-432.4 and 0.5-188.4 µg/mL, respectively. The method was shown to be precise with RSD < 2%. The average recovery of didehydrostemofoline and stemofoline were 98.80 and 99.97%, respectively. Eight samples of S. collinsiae root extracts were analysed and the average contents of didehydrostemofoline and stemofoline were 0.78 and 0.048% w/w, respectively. CONCLUSION The HPLC method developed was appropriate for the analysis of didehydrostemofoline and stemofoline in S. collinsiae root extracts. This work would be useful as a guide for the standardisation of S. collinsiae root extract raw materials and their products as natural pesticides. Copyright © 2012 John Wiley & Sons, Ltd.

Morinda citrifolia L.(Rubiaceae), commonly called noni, is a traditional folk medicinal plant with a long history of use for several diseases. Its anti-inflammation activity has been proposed, but detailed knowledge of this antiinflammation mechanism remains unclear. Here, we investigated the effects of noni extract and its major bioactive component damnacanthal on anti-inflammation in vivo as well as in vitro. Our data demonstrate that noni extract and its bioactive component damnacanthal exhibit suppression of inflammation as evidenced by the suppression of paw and ear edema in rats and mice, and down-regulation of lipopolysaccharide-induced nuclear factor-κB (NF-κB) activity, respectively. As a result, the expression of pro-cytokines, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) were suppressed in the presence of damnacanthal. These results provide a potential use of damnacanthal in the treatment of inflammatory-related diseases.

On the basis of a comparison of 42 Stemona samples, representing eight different species collected and cultivated in Thailand, species-specific accumulation trends of Stemona alkaloids were analyzed. An overview was achieved by comparative HPLC analyses of methanolic crude extracts of underground parts coupled with diode array or evaporative light scattering detectors. All major compounds were isolated and their structures elucidated by NMR and MS analyses. Protostemonine- and stichoneurine-type derivatives dominated, from which the latter characterize S. tuberosa and S. phyllantha accumulating species-specific isomers of tuberostemonine (3). The widespread S. curtisii and S. collinsiae clearly deviate by protostemonine-type derivatives dominated by stemofoline (10) and/or didehydrostemofoline (11). Further diversification within this structural type results from a mutual accumulation of derivatives with a pyrrolo- or pyridoazepine nucleus, leading to chemical variability in S. curtisii and S. aphylla.

Damnacanthal, an anthraquinone compound, is isolated from the roots of Morinda citrifolia L.(noni), which has been used for traditional therapy in several chronic diseases including cancer. Although noni has been consumed for a long time in Asian and Polynesian countries, the molecular mechanisms by which it exerts several benefits are starting to emerge. In this report, we examined systematic approaches on the cancer-suppressing capability of damnacanthal in colorectal tumorigenesis. Damnacanthal exhibits cell growth arrest as well as caspase activity induction in colorectal cancer cells. We also examined several potential target proteins and found that the proapoptotic protein nonsteroidal anti-inflammatory activated gene-1 (NAG-1) is highly induced. Subsequently, we have found that damnacanthal also enhances transcription factor CCAAT/enhancer binding protein β (C/EBPβ), which controls NAG-1 transcriptional activity. Blocking of C/EBPβ by shRNA results in the reduction of NAG-1 expression as well as caspase activity in the presence of damnacanthal. Taken together, these results indicate that damnacanthal increases antitumorigenic activity in human colorectal cancer cells and that C/EBPβ plays a role in damnacanthal-induced NAG-1 expression.

Lemongrass (Cymbopogon citratus Stapf) has been used in cooking and in many traditional medicines; the essential oil contains citral as a major constituent. This study evaluated the antifungal activity of lemongrass oil against Malassezia furfur, an opportunistic yeast associated with dandruff, by using a broth dilution assay. From the minimum fungicidal concentration (MFC) obtained, the oil was then incorporated at different percentages into shampoo formulations. The formulated shampoos were kept at room temperature (28 degrees-30 degrees C) and under accelerated condition (45 degrees C). At the end of the first and sixth weeks, after preparation, all formulations were tested again and the appearance was recorded. Selection of an appropriate formula was based on antifungal activity against M. furfur, the physical appearance, the chemical properties and stability of the formula. Two percent lemongrass oil shampoo provided the required qualities necessary for commercial use. After being kept for 6 weeks at 28 degrees-30 degrees C and 45 degrees C, this formulated shampoo gave MFCs against M. furfur of 75 microl/ml and 18.75 microl/ml, respectively.

The aim of this study was to investigate metabolites of the lichen Laurera benguelensis. A high-performance liquid chromatographic (HPLC) method has been developed for the characterization of xanthones and anthraquinones in extracts of this lichen. Lichexanthone, secalonic acid D, norlichexanthon, parietin, emodin, teloschistin and citreorosein were detected in the lichen samples, which were collected from two places in Thailand. Components of the lichen were identified by relative retention time and spectral data. This is the first time that a detailed phytochemical analysis of the lichen L. benguelensis was reported and this paper has chemotaxonomic significance because very little has been published on the secondary metabolites present in Laurera species. Some of the metabolites were detected for the first time in the family Trypetheliaceae. The results of preliminary testing of benzene extract and its chloroform and methanol fractions showed that all samples showed a weak radical scavenging activity. The chloroform extract showed the highest antioxidant activity.