Quantification of mangiferin in streptozotocin-induced diabetic rat plasma using UPLC-MS/MS: Pharmacokinetic assessment of Gentiana rhodantha extract after oral administration.

Mangiferin, a key bioactive constituent in Gentiana rhodantha, has a favorable impact on reducing blood sugar. A selective and sensitive UPLC MS/MS approach was developed for determining mangiferin in diabetic rats. Employing acetonitrile protein precipitation, chromatographic separation utilized a 2.1×50 mm, 3.5µm C18 column with a mobile phase of 0.1% formic acid aqueous and 5mM ammonium acetate (A, 45%) and acetonitrile (B, 55%) at a 0.5mL min-1 flow rate. Quantification, employing the multiple reaction monitoring (MRM) mode, focused on precursor-to-product ion transitions at m/z 447.1→271.1 for baicalin m/z and 421.0→301.0 for mangiferin. Calibration curves demonstrated linearity in the 1.00~100ng/mL range, with a lower quantification limit for rat plasma set at 1.00ng/mL. Inter- and intra-day accuracies spanned -9.1% to 8.5% and mangiferin mean recovery varied from 82.3% to 86.7%. The adeptly utilized UPLC-MS/MS approach facilitated the exploration of mangiferin pharmacokinetics in diabetic rats.

Preliminary assessment of mutagenic and anti-mutagenic potential of some aminoalkanolic derivatives of xanthone by use of the Vibrio harveyi assay.

The Vibrio harveyi assay was used to evaluate mutagenic and anti-mutagenic effects of four new aminoalkanolic derivatives of xanthone with anticonvulsant activity, to select the potentially safe compounds for further in vivo studies in animal models. The study showed that at a concentration of 40 ng/ml the test compounds were not mutagenic. Additionally, two of the investigated compounds, namely the (R,S)-N-methyl-1-amino-2-propanol derivative of 6-methoxyxanthone (compound III) and the (R)-N-methyl-2-amino-1-butanol derivative of 7-chloroxanthone (compound IV) were strong inhibitors of the mutagenicity induced by 4-nitroquinoline-N-oxide (4-NQO) in V. harveyi strains BB7M and BB7XM. The inhibition percentages for compound IV were 49 (in BB7M) and 69 (in BB7XM), whereas for compound III these percentages were 47 (in BB7M) and 42 (in BB7XM), respectively. The present study demonstrates that four bioactive derivatives of xanthone display no mutagenic activity in the V. harveyi assay. In addition, compounds III and IV demonstrated considerable anti-mutagenic activity in this test. Based on the results obtained here, these compounds could be selected for further studies in animal models, while compounds III and IV should be tested further for their anti-mutagenic properties.

Assessment of systemic interaction between Swertia chirata extract and its Bioactive constituents in rabbits.

The plant Swertia chirata (Gentianaceae) is known for its multifarious medicinal value in the Indian system of medicine (Ayurveda). Its methanol extracts having antidiabetic activity contains mangiferin, amarogentin, amaroswerin, sweroside and swertiamarin as active constituents. The pharmacokinetics of mangiferin and amarogentin have been carried out after intravenous administration of pure standards and extract from S. chirata (CT) in rabbits to assess systemic interaction. The remaining three components were also monitored in plasma for pharmacokinetic estimation based on the ratio analysis method. Mangiferin was characterized by a relative low clearance ( approximately 0.14 L/h/kg) and a lesser volume of distribution ( approximately 0.15 L/kg), while amarogentin exhibited a rapid clearance ( approximately 2.62 L/h/kg) and wide distribution ( approximately 1.08 L/kg) from the systemic circulation. No significant difference was observed in pharmacokinetic parameters of mangiferin and amarogentin either administered alone or as CT formulation in rabbits.