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Abstract Background Hydroxychavicol, isolated from the chloroform extraction of the aqueous leaf extract of Piper betle L., (Piperaceae) was investigated for its antifungal activity against 124 strains of selected fungi. The leaves of this plant have been long in use tropical countries for the preparation of traditional herbal remedies. Methods The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of hydroxychavicol were determined by using broth microdilution method following CLSI guidelines. Time kill curve studies, post-antifungal effects and mutation prevention concentrations were determined against Candida species and Aspergillus species "respectively". Hydroxychavicol was also tested for its potential to inhibit and reduce the formation of Candida albicans biofilms. The membrane permeability was measured by the uptake of propidium iodide. Results Hydroxychavicol exhibited inhibitory effect on fungal species of clinical significance, with the MICs ranging from 15.62 to 500 μg/ml for yeasts, 125 to 500 μg/ml for Aspergillus species, and 7.81 to 62.5 μg/ml for dermatophytes where as the MFCs were found to be similar or two fold greater than the MICs. There was concentration-dependent killing of Candida albicans and Candida glabrata up to 8 × MIC. Hydroxychavicol also exhibited an extended post antifungal effect of 6.25 to 8.70 h at 4 × MIC for Candida species and suppressed the emergence of mutants of the fungal species tested at 2 × to 8 × MIC concentration. Furthermore, it also inhibited the growth of biofilm generated by C. albicans and reduced the preformed biofilms. There was increased uptake of propidium iodide by C. albicans cells when exposed to hydroxychavicol thus indicating that the membrane disruption could be the probable mode of action of hydroxychavicol. Conclusions The antifungal activity exhibited by this compound warrants its use as an antifungal agent particularly for treating topical infections, as well as gargle mouthwash against oral Candida infections.

The present study was conducted to carry out the phytochemical investigation of Tanacetum gracile Hook. f. & Thomson and to develop a method for the simultaneous quantification of the isolated compounds in the extracts of T. gracile growing in different locations. Cluster analysis rectangular similaritymatrixwas performed to understand the chemical fingerprinting variations in the extracts. High-performance liquid chromatography-electrospray ionization-quadrupole-time-of-flight-mass spectrometry (HPLC-ESI-QTOF-MS) was used to quantify four bioactive compounds, and separation of the compounds was achieved on a reverse-phase C8 column using a mobile phase of acetonitrile: 0.1%formic acid inwaterwith a gradient elution bymaintaining the flowrate of 300 μL/min. The QTOF-MS was operated using the electro-spray ionization technique with the positive ion polarity mode. The calibration curves of four marker compounds were linear over the concentration range of 3.12-100 ng/μL (R2 > 0.996). A specific, accurate and precise HPLC-ESI-QTOF-MS method was optimized for the determination of kaempferol, ketoplenolide, tetramethoxyflavone and artemetin both individually and simultaneously. Quantification of these chemical markers in different extracts was carried out using this validated method. Kaempferol was isolated for the first time from T. gracile. [ABSTRACT FROM AUTHOR]

Withania somnifera (L.) Dunal synthesizes large array of pharmacologically active secondary metabolites known as withanolides. It has been extensively investigated in terms of chemistry and bioactivity profiling. However, there exists fragmentary information about the dynamics of withanolide biosynthesis at different phenophases in concert with the expression analysis of key pathway genes. In the present study, two morpho-chemovariants of W. somnifera were harvested at five developmental stages, dissected into leaf and root tissues and assayed for three major withanolides viz. withanolide-A (WS-1), withanone (WS-2) and withaferin A (WS-3) content using high performance liquid chromatography. The present investigation also analyzed the expression pattern of five withanolide biosynthetic pathway genes namely squalene synthase, squalene epoxidase, cycloartenol synthase, cytochrome P450 reductase 1, cytochrome P450 reductase 2 to corroborate with the metabolite flux at different developmental stages. The relative transcript profiles of identified genes at various ontogenetic stages illustrated significant variation in leaf and root tissues and were largely concurrent with the alteration in withanolide pool. Comparatively, the concentrations of withanolide A, withanone and withaferin A along with expression levels of all the five genes were appreciably higher in the leaves than in roots. Relative dynamics in terms of quantitative and qualitative profiles of withanolides in leaf and root tissues revealed least correspondence between the pattern of accumulation, possibly indicting towards de novo tissue-specific biosynthesis. [ABSTRACT FROM AUTHOR]

Background: Hydroxychavicol, isolated from the chloroform extraction of the aqueous leaf extract of Piper betle L., (Piperaceae) was investigated for its antifungal activity against 124 strains of selected fungi. The leaves of this plant have been long in use tropical countries for the preparation of traditional herbal remedies. Methods: The minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of hydroxychavicol were determined by using broth microdilution method following CLSI guidelines. Time kill curve studies, post-antifungal effects and mutation prevention concentrations were determined against Candida species and Aspergillus species "respectively". Hydroxychavicol was also tested for its potential to inhibit and reduce the formation of Candida albicans biofilms. The membrane permeability was measured by the uptake of propidium iodide. Results: Hydroxychavicol exhibited inhibitory effect on fungal species of clinical significance, with the MICs ranging from 15.62 to 500 μg/ml for yeasts, 125 to 500 μg/ml for Aspergillus species, and 7.81 to 62.5 μg/ml for dermatophytes where as the MFCs were found to be similar or two fold greater than the MICs. There was concentration-dependent killing of Candida albicans and Candida glabrata up to 8 x MIC. Hydroxychavicol also exhibited an extended post antifungal effect of 6.25 to 8.70 h at 4 x MIC for Candida species and suppressed the emergence of mutants of the fungal species tested at 2 x to 8 x MIC concentration. Furthermore, it also inhibited the growth of biofilm generated by C. albicans and reduced the preformed biofilms. There was increased uptake of propidium iodide by C. albicans cells when exposed to hydroxychavicol thus indicating that the membrane disruption could be the probable mode of action of hydroxychavicol. Conclusions: The antifungal activity exhibited by this compound warrants its use as an antifungal agent particularly for treating topical infections, as well as gargle mouthwash against oral Candida infections. [ABSTRACT FROM AUTHOR]

The manuscript describes a HPTLC procedure for resolution of constituents, identification and quantification of selected sarsasapogenin glycosides in Asparagus racemosus plant extracts. Shatavarin-IV and immunoside, new sarsasapogenin glycosides were employed as external standards. The analytical procedure will prove handy for identification and quality control of the Rasayana drug on the basis of immunomodulating sarsasapogenin glycoside content. [ABSTRACT FROM AUTHOR]

Out of the several accessions of Cymbopogon citratus (DC) Stapf introduced from Central and West India, one accession coded as RRL(J)CCA12, selected through a mass selection technique, was found to have citral (≈80%) as the major constituent in its essential oil. Citral has tremendous application in the flavour and perfume industries. Plant adaptation was judged by quantifying the regression coefficient (b) value, which was 1.0 using essential oil growth indices. For prediction of essential oil quality index (EOQI), a multiple regression equation was developed for the first time by using essential oil yield/plant and energy summation indices as EOQI (citral %) = 61.6 + 1.09 × essential oil yield/plant (g) - 0.005 × heat use efficiency + 0.675 × phenothermal index. For obtaining a better quality of essential oil (citral ≥78%), the optimal value of independent variable would be: X1 = 2.49; X2 = 0.018 and X3 = 20.47, where X1, X2 and X3 denote essential oil yield/plant, heat use efficiency and phenothermal index, respectively. The validation of the EOQI model is done by correlating the predicted and calculated values of citral (%) which exhibited significant r value = 0.955 at 5% probability level. The thermal requirement of the selectant was ≈5500 degree days to exhibit plant maturity in terms of qualitative and quantitative characteristics of its essential oil at 6.0 vegetative leafing stage, with attainment of plant height ≥1.0 m from previous date of harvest (December 2001). Prediction of essential oil quality by using the mathematical model is helpful for integrating the growth processes and evaluating crop management strategies. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]