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).

Comparative Study of Phytochemical, Antioxidant, and Cytotoxic Activities and Phenolic Content of Syzygium aqueum (Burm. f. Alston f.) Extracts Growing in West Sumatera Indonesia.

Syzygium aqueum, consisting of various fruit colors, is one of the plants that have been used as traditional medicine. This study aims to evaluate and compare phytochemical, antioxidant, and cytotoxic activities and total phenolic content of leaves and stem bark extracts of S. aqueum with pink and red fruits, in order to identify the best extract that can be used as a natural antioxidant. Phytochemical constituents were evaluated qualitatively using chemicals, while cytotoxic activities were identified using the brine shrimp lethality test. Total phenolic content was determined via the Folin-Ciocalteu method. Leaves and stem bark of S. aqueum contained flavonoids, phenolics, and triterpenoids, but the stem bark also contained saponins and alkaloids. Methanol and ethyl acetate extracts of leaves and stem bark were categorized as very powerful antioxidants to DPPH (IC50 9.71-38.69 µg/mL) and hydrogen peroxide (IC50 16.44-44.02 µg/mL), while hexane extracts were inactive. Methanol, ethyl acetate, and hexane extracts of leaves and stem bark were categorized as moderately cytotoxic to A. salina larvae (LC50 104.04-440.65 µg/mL). Comparing leaves and stem barks, antioxidant and cytotoxic activities of stem bark extracts were higher than those of leaves extracts. Total phenolic content of leaves extracts was higher than that of stem bark extracts where the order of total phenolic content progressed from methanol extracts > ethyl acetate extracts > hexane extracts. Therefore, the stem bark of S. aqueum was identified as the better source of natural antioxidant compared with the leaves.

Antioxidant activities, cytotoxic properties and total phenolic content of Syzygium malaccense (L.) Merr. & L.M. Perry leaves extracts: A West Sumatera Indonesian plant.

The purpose of this study was to determine the antioxidant activities and cytotoxic properties of the various extracts of Syzygium malaccense leaves and its correlation with total phenolic content. To determine the antioxidant properties 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydrogen peroxide methods have been used while to determine cytotoxic properties brine shrimp lethality test method has been used. Furthermore, to determine total phenolic content the Folin-Ciocalteu method has been carried out. The results showed that all extracts have antioxidant activity both against DPPH and hydrogen peroxide. IC50 hexane, ethyl acetate and methanol extracts against DPPH were 181.26; 34.35; 36.87 mg/mL respectively and against hydrogen peroxide were 18.24; 12.03; and 13.04mg/mL, respectively. All extracts have also cytotoxicity properties on brine shrimp A. Salina where LC50 of hexane, ethyl acetate and methanol extracts were 204.69, 70.03 and 329.76µg/mL, respectively. Total phenolic content of hexane, ethyl acetate and methanol extracts were 587.17± 19.48, 1617.47±4.63 and 1319.49±9.26µg of gallic acid equivalents (GAE)/10 mg extracts, respectively. Antioxidant activity of these extracts are increased if their phenolic content is increased with the regression equations between IC50 and phenolic content is y= -0.1529x +263.75 with R2 = 0.9289 for DPPH method and y= 0.0062x + 21.745 with R2 = 0.9825 for hydrogen peroxide method.