ABSTRACT
Abstract The aim was to scrutinize the in vivo and in vitro activities against Leishmania tropica with compounds of Oxyresveratrol, Quercetin O-Hexoside, and Quercetin 3-Glucoside. The in vitro outcomes against Leishmania were analyzed for 24-48 hours on L. tropica KWH23 promastigotes with compounds materials having 50 - 200 µg/mL concentration with negative control and standard drug Amphotericin B. The compounds were analyzed in L. tropica infected BALB/c mice against Leishmania tropica. The Quercetin 3-Glucoside shows mean inhibition of extracellular promastigotes after 48 hours at 50, 100, 150, 200 µg/mL were 91.02 ± 0.12, 94.50 ± 0.07, 96.15 ± 0.17 and 97.01 ± 0.08 % respectively. In BALB/c mice, the intracellular amastigotes were 91% cured at 200 µg/mL and mean lesion size decreased to 0.41 ± 0.21 mm (p < 0.01). The result shows that Quercetin 3-Glucoside possesses significant anti-leishmanial activity.
ABSTRACT
Cellular oxidative stress is caused by an imbalance in the redox status and manifests as hyperpigmentation disorders.Reactive oxygen species, particularly hydrogen peroxide (H2O2) as the highly reactive hydroxyl radicals, promotethe melanin production through the induction of tyrosinase enzyme activity. In this study, the antioxidant activity ofoxyresveratrol was investigated by 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays. In addition, melanin biosynthesis, tyrosinase activity, and cellular oxidants due to thebioactive component, oxyresveratrol, were determined in B16 cells by melanin content assay, cellular tyrosinase activityassay, and the dichloro-dihydro-fluorescein diacetate (DCFH-DA) assay, respectively. Hydrogen peroxide induced themelanogenesis through tyrosinase activity-related cellular oxidants, whereas oxyresveratrol showed a potent antioxidantactivity by DPPH and ABTS assays. At the concentrations of 10 and 12.5 µg/ml, oxyresveratrol significantly inhibitedmelanogenesis in B16 melanoma cells and also suppressed tyrosinase activity and cellular oxidants. Effective doses ofoxyresveratrol inhibit melanogenesis through bioactivity of cellular tyrosinase-related oxidative stress
ABSTRACT
Oxyresveratrol is a polyphenolic compound found in Mulberry (Morus alba L.) twigs and has known as a skinlightening agent. Many methods can be applied to extract oxyresveratrol from Mulberry twigs. This researchaimed to optimize the extraction method by using surfactant Tween 80 and Tween 20-based microwave-assistedextraction (MAE). Extraction parameters, including solvent concentration, liquid–solid ratio, and extraction time foroxyresveratrol, were optimized using response surface methodology based on Box–Behnken Design. This researchalso extracted the oxyresveratrol by maceration, and then the oxyresveratrol content from each extraction methodwas compared. Oxyresveratrol content was determined using high-performance liquid chromatography (HPLC). ForTween 80, the optimum condition was obtained at 10.5 mM, 30:1 ml/g liquid–solid ratio, and 10 minutes extractiontime. For Tween 20, the optimum condition was obtained at 100 mM, 40:1 ml/g liquid–solid ratio, and 5 minutesextraction time. Oxyresveratrol content was 0.0146 mg/g dried sample and 0.0172 mg/g dried sample at the optimumcondition of Tween 80 and Tween 20 surfactant, respectively. Meanwhile, the oxyresveratrol content of the macerationmethod with 96% ethanol was 1.5704 mg/g dried sample. In conclusion, these results show that the application ofTween 80 and Tween 20 as solvents for MAE of Oxyresveratrol from mulberry twigs was not fully successful sinceother extraction conditions should be considered, such as temperature, pH, and microwave energy.