Development and validation of TLC-densitometry method for quantification of tetraprenyltoluquinone in the stem bark hexane extract of Garcinia cowa roxb.

A thin layer chromatography (TLC) method coupled with densitometry was optimized and established to quantify tetraprenyltoloquinon (TPTQ) in the hexane extract of Garcinia cowa roxb stem bark. The stationary phase was TLC plates of silica gel 60 F254, with a thickness of 250 µm, while a mobile phase was the mixture of hexane: chloroform: ethyl acetate: formic acid in the ratio of 20:70:9:1 was selected for the chromatographic system. TLC separation of the components was followed by densitometric analysis at 230 nm. The chromatogram revealed a tight spot for TPTQ at the Rf = 0.41 ± 0.03). The value of the regression equation (r2 = 0.992) demonstrated an excellent linear association between peak area and TPTQ amount in the 250-750 µg.spot-1 range. The precision, specificity, and accuracy of the approach were all validated. The 72.65 and 242.15 µg.spot-1 were found as the limit of detection and quantification, respectively. The proposed TLC method can be considered for identifying and quantifying TPTQ in Garcinia cowa Roxb bark hexane extracts.

Simultaneous TLC-densitometric analysis of catechin, pyrocatechol and quercetine in gambir block from Pesisir Selatan.

The goal of this study is to use the TLC-densitometric method to determine the concentration of catechin, pyrocatechol, and quercetine in gambir block extracts in a reliable and efficient manner. The best eluent is a mixture of chloroform: ethyl acetate: glacial acetic acid (4:4:2). The concentration of catechin, pyrocatechol and quercetine in gambir block was found to be 25.50 ± 3.13, 0.91 ± 0.60 and 0.83 ± 0.34% (w/w) w/w respectively. The linearity was obtained between 750-2500, 50-350, and 50-350 µg/spot. 12.49-41.63, 0.48-1.60, 3,85-12.83 µg/spots were found to represent the LOD and LOQ, respectively. The proposed approach exhibited great sensitivity, precision, and accuracy, as well as strong linearity.

Single dose oral pharmacokinetic profile rubraxanthone in mice.

Rubraxanthone is a main active constituent of kandis (Garcinia cowa Roxb), has showed many biological activity including antimicrobial, anti hypercholesterolemic, antiplatelet, antioxidant, cytotoxic, and anti-inflammatory properties. To the best of our knowledge, no reports on the pharmacokinetics (PK) of this rubraxanthone have been published. The PK of rubraxanthone in mice was examined after a single oral dose of 700 mg/kg rubraxanthone suspension in virgin coconut oil. Plasma samples were collected at different time points and further analyzed using validated chromatographic method. Pharmacokinetic parameters were calculated from observed plasma concentration-time profile. The maximum concentration of rubraxanthone in plasma was discovered in 1.5 h. The peak plasma concentration (Cmax) was 4.267 µg/mL, and the area under the curve (AUCt0-t ∞ ) was 560.99 µg h/L, with a 6.72-hour terminal half-life (T1/2). The volume of distribution (Vd/F) was 1200.19 mL/kg and 1123.88 mL/h/kg clearance (Cl/F).

High Performance Thin layer Chromatography: Densitometry Method for Determination of Rubraxanthone in the Stem Bark Extract of Garcinia cowa Roxb.

CONTEXT: Garcinia cowa is a medicinal plant widely grown in Southeast Asia and tropical countries. Various parts of this plant have been used in traditional folk medicine. The bark, latex, and root have been used as an antipyretic agent, while fruit and leaves have been used as an expectorant, for indigestion and improvement of blood circulation. AIMS: This study aims to determine the concentration of rubraxanthone found in ethyl acetate extract of the stem bark of G. cowa by the high-performance thin-layer chromatography (HPTLC). MATERIALS AND METHODS: HPTLC method was performed on precoated silica gel G 60 F254 plates using an HPTLC system with a developed mobile-phase system of chloroform: ethyl acetate: methanol: formic acid (86:6:3:5). A volume of 5 µL of standard and sample solutions was applied to the chromatographic plates. The plates were developed in saturated mode of twin trough chamber at room temperature. The method was validated based on linearity, accuracy, precision, limit of detection (LOD), limit of quantification (LOQ), and specificity. The spots were observed at ultraviolet 243 nm. RESULTS: The linearity of rubraxanthone was obtained between 52.5 and 157.5 ppm/spot. The LOD and LOQ were found to be 4.03 and 13.42 ppm/spot, respectively. CONCLUSION: The proposed method showed good linearity, precision, accuracy, and high sensitivity. Therefore, it may be applied for the quantification of rubraxanthone in ethyl acetate extract of the stem bark of G. cowa. SUMMARY: High performance thin layer chromatography (HPTLC) method provides rapid qualitative and quantitative estimation of rubraxanthone as a marker com¬pound in G. cowa extract used for commercial productRubraxanthone found in ethyl acetate extracts of G. cowa was successfully quantified using HPTLC method. Abbreviations Used: TLC: Thin-layer chromatography, HPTLC: High-performance thin-layer chromatography, LOD: Limit of detection, LOQ: Limit of quantification, ICH: International Conference on Harmonization.