Panadda Phattanawasin

Lignan glycosides and flavonoids from Saraca asoca with antioxidant activity

Five lignan glycosides, lyoniside, nudiposide, 5-methoxy-9-β-xylopyranosyl-(−)-isolariciresinol, icariside E3, and schizandriside, and three flavonoids, (−)-epicatechin, epiafzelechin-(4β→8)-epicatechin and procyanidin B2, together with β-sitosterol glucoside, were isolated from a methyl alcohol (MeOH) extract of Saraca asoca dried bark. Their structures were determined by 1D and 2D nuclear magnetic resonance (NMR) and mass spectroscopic analysis. Antioxidant activities were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay.

A new lignan from Aphanamixis polystachya

A new lignan, polystachyol (1), two lignan glycosides, lyoniside (2) and nudiposide (3), and a sterol, ergosta-4,6,8(14),22-tetraen-3-one (4), with stigmasterol, and oleic and linoleic acids, have been isolated from an MeOH extract of the dried bark of Aphanamixis polystachya. The structures of the isolated compounds were elucidated by analysis of 1D and 2D NMR and mass spectroscopic data. The compounds did not have growth inhibitory activity against HeLa cells.

Quantitative determination of sibutramine in adulterated herbal slimming formulations by TLC-image analysis method

A simple thin layer chromatographic (TLC)-image analysis method was developed for rapid determination and quantitation of sibutramine hydrochloride (SH) adulterated in herbal slimming products. Chromatographic separation of SH was achieved on a silica gel 60 F(254) TLC plate, using toluene-n-hexane-diethylamine (9:1:0.3, v/v/v) as the mobile phase and Dragendorff reagent as spot detection. Image analysis of the scanned TLC plate was performed to quantify the amount of SH. The polynomial regression data for the calibration plots showed good linear relationship in the concentration range of 1-6 μg/spot. The limits of detection and quantitation were 190 and 634 ng/spot, respectively. The method gave satisfactory specificity, precision, accuracy, robustness and was applied for determination of SH in herbal formulations. The contents of SH in adulterated samples determined by the TLC-image analysis and TLC-densitometry were also compared.

Application of Scion image software to the simultaneous determination of curcuminoids in turmeric (Curcuma longa)

INTRODUCTION Curcumin, desmethoxycurcumin and bisdesmethoxycurcumin are bioactive constituents of turmeric (Curcuma longa). Owing to their different potency, quality control of turmeric based on the content of each curcuminoid is more reliable than that based on total curcuminoids. However, to perform such an assay, high-cost instrument is needed. OBJECTIVE To develop a simple and low-cost method for the simultaneous quantification of three curcuminoids in turmeric using TLC and the public-domain software Scion Image. METHODOLOGY The image of a TLC chromatogram of turmeric extract was recorded using a digital scanner. The density of the TLC spot of each curcuminoid was analysed by the Scion Image software. The density value was transformed to concentration by comparison with the calibration curve of standard curcuminoids developed on the same TLC plate. RESULTS The polynomial regression data for all curcuminoids showed good linear relationship with R(2) > 0.99 in the concentration range of 0.375-6 microg/spot. The limits of detection and quantitation were 43-73 and 143-242 ng/spot, respectively. The method gave adequate precision, accuracy and recovery. The contents of each curcuminoid determined using this method were not significantly different from those determined using the TLC densitometric method. CONCLUSION TLC image analysis using Scion Image is shown to be a reliable method for the simultaneous analysis of the content of each curcuminoid in turmeric.

Weed growth inhibitors from Aspergillus fischeri TISTR 3272

Chloroform and ethyl acetate extracts of Aspergillus fischeri TISTR 3272 showed good growth inhibitory activity on Mimosa pigra and Echinochloa crus-galli. Bioassay-directed fractionation of the active extracts led to the isolation of five known compounds, (+)-terrein (1), (−)-6-hydroxymellein (2), two diketopiperazines (cyclo-(S-Pro-S-Leu) (3) and cyclo-(S-Pro-S-Val) (4)) and butyrolactone I (5). Compounds 2–5 were reported for the first time in this fungus. Their structural determinations were based on analyses of spectroscopic data and their weed growth inhibitory effects were assessed.

Stability-Indicating TLC-Image Analysis Method for Quantification of Ceftriaxone Sodium in Pharmaceutical Dosage Forms

A simple and rapid thin-layer chromatographic (TLC)-image analysis method has been established for stability-indicating studies and quantification of ceftriaxone sodium (CFX) in bulk and in pharmaceutical dosage forms. Chromatographic separation was achieved on RP-18 F254S plates with 15% (w/v) ammonium acetate buffer (pH 6.2)-methanol-acetonitrile 12:0.5:0.25 (v/v) as mobile phase. The method was validated in accordance with International Conference on Harmonization (ICH) guidelines. Polynomial regression data for the calibration plot were indicative of a good linear relationship between response and amount in the range 1–8 µg per spot. The limits of detection and quantitation were 228 and 759 ng per spot, respectively. The precision, accuracy, and robustness of the method were satisfactory. Good separation was achieved between CFX and the degradation products obtained under different stress conditions, suggesting the method is stability-indicating. The CFX content of dosage forms determined by use of TLC-image analysis, TLC-densitometry, and the official HPLC method was not significantly different. The proposed TLC method was found to enable reliable and convenient analysis of CFX and can be used as a stability- indicating assay.

Stability-indicating TLC—image analysis method for determination of andrographolide in bulk drug and Andrographis paniculata formulations

A simple and rapid thin-layer chromatographic (TLC)–image analysis method was developed for stability-indicating studies and determination of andrographolide in bulk drug and in Andrographis paniculata formulations. Good chromatographic separation of andrographolide and the degradation products under various stress conditions was achieved on a silica gel G60 F254 TLC plate with the use of two mobile phases, dichloromethane—toluene—ethanol (6:3:1, v/v/v) and toluene—ethyl acetate—formic acid (5:3.5:1.5, v/v/v) and p-anisaldehyde as visualization reagent. Image analysis of the scanned TLC plate was performed by Sorbfil TLC Videodensitometer, UN-SCAN-IT, JustTLC, and ImageJ software to measure the quantity of the dark bluecolored band of andrographolide on a TLC plate. The TLC—image analysis method was validated in terms of specificity, linearity, sensitivity, precision, accuracy, and robustness and was also applied for determination of the amount of andrographolide in A. paniculata formulations and the cont...

Thin-Layer Chromatography-Image Analysis Method for the Simultaneous Quantification of Andrographolide and Related Diterpenoids in Andrographis paniculata

Andrographis paniculata (Burn. f.), commonly known in Thailand as Fa-Tha-Lai, is widely used in the treatment of common colds, flu, and uncomplicated respiratory infections [1]. The plant is also reported to possess a variety of pharmacological activities, e.g., analgesic, hypoglycemic, antibacterial, antiviral, and antineoplastic activities [2–4]. In Thailand, A. paniculata formulations, capsules, tablets, and pills, have been added to the national herbal drug list and approved by the Food and Drug Administration for the treatment of colds and noninfectious dysentery. The therapeutic activities of this plant have been attributed to andrographolide (AL), the major constituent, and other related diterpenoid derivatives, e.g., neoandrographolide (NAL) and deoxyandrographiside (DAS), etc. [5–7]. In Thai Herbal Pharmacopoeia (THP), it was specified that the acceptance criteria for the andrographolide content in Andrographis herb was not to be less than 1.0%, w/w as determined by high-performance liquid chromatography (HPLC) [8].