Antioxidant study of flavonoid derivatives from the aerial parts of Rhus natalensis growing in Saudi Arabia

Phytochemical study of the CH[2]Cl[2] soluble fraction of the aerial parts of R. natalensis resulted in the isolation and identification of six flavonoid derivatives, beta -amyrin and beta -sitosterol glucoside [daucosterol]. The isolated compounds were identified utilizing physical, chemical and different spectral methods including UV, 1D- 2D-NMR and MS. The compounds were identified as four flavanones; 7-O-methyl hesperetin [1], 7-O-methyl naringenin [4], [-]- homoeriodictyol [eriodictyonone] [5], eriodictyol-7-methyl ether [6] and two flavones; 7-O-methyl isokaemferide [2] and genkwanin [3]. The isolated compounds as well as some available standards representing structurally similar flavones and flavanones were used to study their antioxidant potential using DPPH and try to explore the impact of structures on the antioxidant activity. In other assays flavanones were less active than flavones as antioxidant due to lack of the C-4 carbonyl group in conjugation with 2,3-double bond. However, in DPPH assay based on the ability of molecules to donate hydrogen flavanones were found more active than flavones

Quantification of glycyrrhizin in anti-stress herbal formulations by validate HPTLC method: a rational paradigm towards quality control of herbals

In the present study an analytical method of high-performance thin-layer chromatography [HPTLC] has been developed for quantification of glycyrrhizin for marketed antistress liquorice root capsules [LRC] and herbal tea [HT]. Chromatography was performed by using mobile phase ethyl acetate [EA]: glacial acetic acid [GAA]: Methanol [MeOH]: water [H2O] in proportion of 6:2:2:1, v/v/v/v. The developed plate was scanned and quantified densitometrically at absorption maxima 254nm. The method was validated for various analytical parameters viz. precision, accuracy, recovery, robustness, specificity, detection and quantification limits. The developed system was found to give compact spot for glycyrrhizin [Rf = 0.33 +/- 0.001]. The linearity relationship was described by the equation Y=6.841X+ 70.428. The limit of detection [34 ng band-1], limit of quantification [101ng band-1], recovery [99.4-99.8%], and precision [

Quantitative analysis of biomarker rutin in different species of genus Ficus by validated NP and RP-HPTLC methods

Biomarker rutin was analyzed in methanol extracts of leaves of five different species of genus Ficus [Ficus carica, Ficus nitida, Ficus ingens, Ficus palmata and Ficus vasta] by NP-HPTLC [Method I] and RP- HPTLC methods [Method II]. The development and validation for method I was carried out with silica gel 60F[254] plates using EA: GAA: FA: H[2]O [10:1:1:2.5, v/v/v/v] as developing system. Method II was carried out on silica gel 60F[254] RP-18 plates using mobile phase ACN: H[2]O [4:6 v/v]. Both analyses were scanned at 305 nm and were found to give well resolved peak of rutin at Rf 0.28 +/- 0.01 and 0.68 +/- 0.03 for Method I and Method II, respectively. The percentage of rutin was found to be 0.51% and 0.66% in F. ingens, 0.24% and 0.54% in F. palmata and 0.14% and 0.17% in F. vasta by Method I and Method II, respectively. Method II [RP-HPTLC] was found to be more accurate, precise and sensitive than Method I. Method II can be used as an important tool for standardization and quality control of bulk drugs and in-process formulations of rutin