Jurnal Teknologi dan Industri Pangan (Dec 2006)
PENGARUH SODIUM CHORIDE TERHADAP SIFAT TERMAL PROTEIN 30 kDa YANG DIISOLASI DARI BIJI MLINJO [Effect of Sodium Chloride on Thermal Properties of a 30 kD Protein Isolated from Mlinjo Seed]
Abstract
Antioxidant activity of some extracts of javanese ginseng root was investigated. Javanese ginseng root extracts were prepared by solvent extraction using methanol, ethanol (96%), ethanol (70%), acetone, and hexane. Total antioxidant activity of the extracts was measured by ferric thiocyanate method, whereas radical scavenging capacity and reducing power were measured by the 1,1-diphenyl-2-picrylhydrazyl and the reducing potential methods, respectively. The result showed that the highest total antioxidant activity was observed in acetone and methanol extracts. It was supposed that the ability of these extracts for partitioning at the interface of the emulsion in the tested oxidation system was the highest among other extracts, therefore it had the best activity to inhibit oxidation. The highest radical scavenging capacity measured by EC50 was observed in acetone extract. The type of phenolic compounds of this extract was suggested to be responsible for the highest radical scavenging capacity. Different phenomena occurred for reducing power. Methanol extract had the highest reducing power and the least is hexane and acetone extract. It was suggested that each extracts comprised different types of phenolic based on different polarity of solvents used for extraction. The antioxidant compounds of javanese ginseng root extracts were primary antioxidant based on these ability to scavenge free radical. It could be concluded that acetone was the best solvent for antioxidant extraction of javanese ginseng root. However, all tested antioxidant mechanisms in this research showed that vitamin E (1000 ppm) had better activity than javanese ginseng root extracts (1000 ppm) for all types of solvent. Javanese ginseng extracts might contain other compounds that not responsible for antioxidant activity, therefore at the same concentration the activity were lower than vitamin E.
