The Effects of Cosmos caudatus (Ulam Raja) on Detoxifying Enzymes in Extrahepatic Organs in Mice.

‘Ulam Raja’ or Cosmos caudatus is a common appetizer (ulam) consumed by the Malay community in Malaysia. However, in vivo studies pertaining to its antioxidant and chemoprotective properties are lacking. This study was done to determine the effects of Cosmos caudatus on detoxifying enzymes in extrahepatic organs (lungs, kidneys and stomach) in mice. Thirty adult male white mice were treated orally for 21 days with different doses of ‘Ulam Raja’ aqueous extract (UR) (100, 500, 1000mg/kg). The control group was given normal saline by oral gavage. Mice fed with diet containing 0.5% butylated hydroxyanisole (BHA) were used as positive control. After 21 days, the mice were sacrificed and extrahepatic organs were harvested. The activities of several detoxifying enzymes [catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), DT-diaphorase (DTD)] were measured. Lipid peroxidation level was determined by measuring malondialdehyde (MDA) concentration. In lungs, 100, 500 & 1000 mg/kg UR oral supplementation resulted in significant increases in CAT, SOD and GST activities. DTD activity in lungs was significantly increased in mice treated with 1000mg/kg UR. MDA levels in lungs were significantly decreased in mice treated with 100mg/kg & 500 mg/kg UR but was significantly increased in mice treated with 1000mg/kg UR. In kidneys, DTD activity was significantly increased in mice treated with 1000mg/kg UR. In stomach, CAT activity was significantly increased in mice treated with 1000mg/kg UR. The results showed that Cosmos caudatus supplementation in mice could protect extrahepatic organs from xenobiotic and oxidative injury. This indicates that consumption of ‘Ulam Raja’ might be a useful chemoprotective measure.

Effect of Aloe vera gel extract on antioxidant enzymes and azoxymethane-induced oxidative stress in rats.

The present work was undertaken with a view to study the effect of oral feeding of 2% Aloe vera gel extract (AGE) for 30 days on azoxymethane (AOM)-induced oxidative stress in rats. It was observed that AOM administration resulted in a significant increase in malondialdehyde and conjugated dienes, with reduction in hepatic glutathione (GSH), vitamin A and uric acid contents. AOM-induced reduction in hepatic GSH and uric acid was brought back to normal by AGE. There was a significant raise in hepatic catalase, superoxide dismutase and glucose-6-phosphate dehydrogenase (G-6-PD) activities as a result of feeding of the extract. Ingestion of the extract effected reduction in AOM-induced colonic GSH-peroxidase, G-6- PD and glutathione S-transferase and femur bone marrow micronuclei formation. Hence, it is suggested that Aloe vera gel extract possess the ability to reduce AOM- induced oxidative stress and toxicity in liver.

Protection by Chrysanthemum zawadskii extract from liver damage of mice caused by carbon tetrachloride is maybe mediated by modulation of QR activity

Our previous study demonstrated that methanolic extract of Chrysanthemum zawadskii Herbich var. latilobum Kitamura (Compositae) has the potential to induce detoxifying enzymes such as NAD(P)H:(quinone acceptor) oxidoreductase 1 (EC 1.6.99.2) (NQO1, QR) and glutathione S-transferase (GST). In this study we further fractionated methanolic extract of Chrysanthemum zawadskii and investigated the detoxifying enzyme-inducing potential of each fraction. The fraction (CZ-6) shown the highest QR-inducing activity was found to contain (+)-(3S,4S,5R,8S)-(E)-8-acetoxy-4-hydroxy-3-isovaleroyloxy-2-(hexa-2,4-diynyliden)-1,6-dioxaspiro [4,5] decane and increased QR enzyme activity in a dose-dependent manner. Furthermore, CZ-6 fraction caused a dose-dependent enhancement of luciferase activity in HepG2-C8 cells generated by stably transfecting antioxidant response element-luciferase gene construct, suggesting that it induces antioxidant/detoxifying enzymes through antioxidant response element (ARE)-mediated transcriptional activation of the relevant genes. Although CZ-6 fraction failed to induce hepatic QR in mice over the control, it restored QR activity suppressed by CCl4 treatment to the control level. Hepatic injury induced by CCl4 was also slightly protected by pretreatment with CZ-6. In conclusion, although CZ-6 fractionated from methanolic extract of Chrysanthemum zawadskii did not cause a significant QR induction in mice organs such as liver, kidney, and stomach, it showed protective effect from liver damage caused by CCl4.

Mercury detoxifying enzymes within endospores of a broad-spectrum mercury resistant Bacillus pasteurii strain DR2.

Bacillus pasteurii DR2, a broad-spectrum Hg-resistant bacterial strain, exhibited delayed sporulation and less mercury volatilization in the presence of mercury compounds. However, Hg-sensitive Bacillus subtilis sporulated quickly in the presence of HgCl2 and volatilized no mercury. Levels of Hg2+-reductase and organomercurial lyase in the endospores of Bacillus pasteurii DR2 were lower than those in vegetative cells.