In vitro peroxynitrite scavenging activity of diarylheptanoids from Curcuma longa

Abstract

To investigate the antioxidant activity of mustard leaf (Brassica juncea), we prepared four fractions (CH(2)Cl(2), EtOAc, BuOH and H(2)O fractions) and examined their radical scavenging activities in vitro and in vivo. Based on the in vitro results of spin trapping and 1,1-diphenyl-2-picrylhydrazyl radical, we carried out an in vivo study with the BuOH fraction to investigate its effect on oxidative stress in rats with streptozotocin-induced diabetes. We found that in comparison with untreated diabetic control rats, oral administration of the BuOH fraction (100 or 200 mg/kg body weight/day for 10 days) induced a significant decrease in serum glucose and glycosylated protein, which is glycosylated with hemoglobin as an indicator of oxidative stress. Moreover, administration of the BuOH fraction also effectively reduced the serum superoxide and nitrite/nitrate levels. Furthermore, the levels of thiobarbituric acid-reactive substances in serum and liver were also significantly lower than in the control group. These results indicate that the BuOH fraction of mustard leaf controls glucose metabolism and reduces lipid peroxidation as well as the level of oxygen radicals, ameliorating the damage caused by oxidative stress in diabetes.

Curcuma longa Extract Protects against Gastric Ulcers by Blocking H2 Histamine Receptors

“…There are two previous reports about the constituents in the C. longa EA extract. 23,24) In these studies, curcumin I (1), curcumin II (2), and curcumin III (3) were isolated as active principles in the EA extract. Therefore, further experiment is required whether these compounds are related with H 2 R regulation and gastric acid secretion.…”

Curcumin and Kolaviron Ameliorate Di‐n‐Butylphthalate‐Induced Testicular Damage in Rats

“…Garcinia kola seeds and C. longa rhizomes were purchased from a local vendor in Ibadan, Nigeria. Kolaviron was extracted from the fresh seeds of G. kola and characterized according to the method of Iwu et al [8], while curcumin was isolated from C. longa rhizomes and characterized according to published method [15].…”

Prospects of curcumin as an additive in storage solutions: a study on erythrocytes

“…AOPP levels in the groups with additives were much lower than those in the control group, substantiating that curcumin was beneficial to proteins. P-SH increased in samples with higher concentrations of curcumin, indicating that few free radicals were successfully scavenged by curcumin (15,16,(18)(19)(20)(21)(22)25,29); this also indicated the reversibility of the disulfide groups to reduced SH. Similar results were observed in plasma from stored blood (64).…”

“…Curcumin has been found to be at least ten times more potent than Vitamin E (13). Curcumin is a powerful free radical scavenger (hydrogen peroxide, singlet oxygen, hydroxyl, superoxide, peroxyl, peroxynitrite, and nitrite radicals) (14)(15)(16)(17)(18)(19)(20)(21)(22) and neutralizes 2,2-diphenyl-1-picrylhydrazyl (20,(22)(23)(24). Curcumin has both antioxidant and prooxidant effects in oxygen radical reactions, acting as a scavenger of hydroxyl radicals or a catalyst in the formation of hydroxyl radicals, depending on the experimental conditions (19,(25)(26)(27).…”