Rhanterium epapposum, native to the Arabian Peninsula, is traditionally used to cure skin infections. The objective is to screen the phytochemical content and antimicrobial activity of aqueous, methanol and 80% methanol extracts of aerial parts of R. epapposum. The phytochemical screening of aqueous, methanolic, and 80% methanol extracts of R. epapposum was conducted using gas chromatographymass spectrometry. The antimicrobial activities of the extracts were assessed by well diffusion and microdilution methods. Qualitative phytochemical analysis revealed the presence of 2-methoxy-4-vinylphenol in all three extracts, whereas ethanol, 2-methoxy-, acetate; n-hexadecanoic acid; and 2,3-butanediol are present in higher amount exclusively in the methanol, 80% methanol and aqueous extracts of the aerial parts of R. epapposum, respectively. The highest antibacterial activity was shown by the aqueous extract S. aureus, P. aeruginosa, E. cloacae, and K. pneumoniae, methanolic extract against S. aureus, methicillin-resistant S. aureus, and E. coli, and 80% methanol extract against S. epidermidis, and S. paucimobilis. Interestingly, 80% methanol extracts showed the highest antifungal activity against C. albicans, C. guillermondii, C. vaginalis, C. utilis, and C. tropicalis. The aerial parts of R. epapposum showed broad-spread antimicrobial activity against bacteria and fungi. Especially, the 80% methanol extract showed potent antifungal activity against all the tested fungal strains.

A simple and sensitive bioanalytical high-performance liquid chromatographic method with ultraviolet detection was developed and validated for the quantification of febuxostat (FEB) in human plasma. Ketoprofen was used as an internal standard. The analytes were extracted from human plasma samples by precipitation with acetonitrile. The reconstituted samples were chromatographed on C18 Bondapack 10 µm, 250 × 4.6 mm, Waters Column (Ireland) by using a mixture of acetonitrile and 0.5% aqueous phosphoric acid (pH 3) (52 : 48, v/v) as the mobile phase. The chromatographic separation was isocratically performed at room temperature at a flow rate of 1.0 mL/min with UV detection at 315 nm. The method exhibited a linear dynamic range over 0.05–5.00 µg/mL FEB in human plasma. The lower limit of quantification was 0.05 µg/mL. The results of the intra- and interday precision and accuracy studies were within the acceptable limits. The validated method was successfully applied for the determination of FEB in human plasma samples for application in bioequivalence studies.

The aim of the present study was to assess in vitro the antiradical and antioxidant activities of successive extracts and semi-purified fractions from Rumex vesicarius L. In the present work, three extracts (n-Hexane, ethyl acetate and methanol) and 22 column fractions of methanolic extract (as promising extract) were evaluated against 2,2-diphenyl- 1-picrylhydrazyl (DPPH•) and 2,2-azinobis (3-ethylbenzothiazoline- 6-sulfonic acid) (ABTS) radical scavenging methods as antiradical and antioxidant activities compared with Butylated hydroxytoluene (BHT) as synthetic standard and silver nanoparticles of methanolic extract (Ag-NPs-Me), in addition to analysis of chemical constituents of extract and fraction using Gas chromatography–mass spectrometry (GC-MS). The obtained results revealed that, both methods go parallel showing that the concentration of extract and incubation time are dependent and proportional with phenolic compounds concentration. Absolute methanol extract recorded the highest antioxidant activity when compared with the other crude extracts with 79.3 and 78.8% against DPPH and ABTS respectively when compared with BHT as synthetic standard (89.4 and 89.9%) against DPPH and ABTS respectively. Calculation of the antiradical activity units showed the highest values of methanolic extract and its promising fraction (No. 12) after 300 seconds (5 minutes) comparing with antioxidant activity (30 min). Also, the antioxidant activity increased with synthetic Ag-NPs-Me when compared with methanolic extract by (IC50= 53.9 and 74.6 µg/ml respectively). Thus, the GC-MS analysis of successive extracts of R. vesicarius L showed a highly complex profile, containing approximately 24 different components. One pure compound was identified from fraction No. 12. The identified compound was l-(+)- ascorbic acid 2, 6-dihexadecanoate. The data also revealed presence of closely similar antioxidant activities in methanolic extract or its pure compounds with BHT when mixed at different proportions. From the obtained results it could be concluded that R. vesicarius methanolic extracts and fractions can be extensively used in the production of potential antioxidant, antiradical and AgNPs-Me for biomedical application on the consumer’s health.