Hendra Susanto

Structural, Optical, and Antifungal Characters of Zinc Oxide Nanoparticles Prepared by Sol-gel Method

The preparation of zinc oxide nanoparticles has been successfully done by employing a sol-gel route. The x-ray diffraction data analysis presented that the zinc oxide particles crystallized as hexagonal wurtzite structure and sized in nanometric scale of 35.8 nm. The scanning electron microscopy image showed that the sample had agglomeration pattern with the particles size of 38.2 nm. Such results were confirmed by a synchrotron small-angle x-ray scattering that the prepared sample agglomerated in 3-dimensional structure with a fractal dimension of about 3. The functional group of the Zn-O as the main component of zinc oxide were observed at the wavelengths of about 454 and 523 cm−1. Moreover, the optical band gap energy of the zinc oxide nanoparticles was of 3.53 eV. Excitingly, the powdered sample in this work had an average inhibition zone diameter of 4.59 mm for Candida albicans fungus. Therefore, the prepared zinc oxide nanoparticles exhibited imperative materials for antifungal agent.

Antiinflammatory effect of porterweed (Stachytarpheta jamaicensis (L.) Vahl) leaf extract to TNF-ɑ expression

Porterweed (Stachytarpheta jamaicensis (L.) Vahl) contain many fl avonoids compound. It is a potential candidate to supress the infl ammatory process through down regulation of TNF-α level as a potent pro-infl ammatory cytokine in chronic infl ammation cases. The aim of this research was to improve the effect of Porterweed leaf extract to the TNF-α level and considered the optimum dosage in wistar rats with chronic infl ammation model. Twenty fi ve rats was divided into negative control group, positive control group, and treatment groups with dosage 50, 100 and 150 mg/kg BW. Data obtained through microscopical histologic observation on aortic organ after immunohistochemistry staining and was analyzed descriptively. The result revealed that Porterweed leaf extract is able to inhibit the increasing of TNF-α level. This phytochemical substance is predicted capable of preventing the oxidation reaction progession of cyclooxygenase-2 (COX-2) to produce prostaglandins. The decreasing of prostaglandin level causes a negative feedback to TNF-α production and iniciating the declining level of TNF-α. Thus, the Porterweed leaf extract indicates supress chronic infl ammatory process through down regulation of TNF-α and prostaglandin activity in optimum dose 150 mg/kg bw.