Isolation and Characterization of Novel Denitrifying Bacterium Geobacillus sp. SG-01 Strain from Wood Chips Composted with Swine Manure.

Nitrate contamination in ground and surface water is an increasingly serious environmental problem and only a few bacterial strains have been identified that have the ability to remove nitrogen pollutants from wastewater under thermophilic conditions. We therefore isolated thermophilic facultative bacterial strains from wood chips that had been composted with swine manure under aerated high temperature conditions so as to identify strains with denitrifying ability. Nine different colonies were screened and 3 long rod-shaped bacterial strains designated as SG-01, SG-02, and SG-03 were selected. The strain SG-01 could be differentiated from SG-02 and SG-03 on the basis of the method that it used for sugar utilization. The 16S rRNA genes of this strain also had high sequence similarity with Geobacillus thermodenitrificans 465(T) (99.6%). The optimal growth temperatures (55°C), pH values (pH 7.0), and NaCl concentrations (1%) required for the growth of strain SG-01 were established. This strain reduced 1.18 mM nitrate and 1.45 mM nitrite in LB broth after 48 h of incubation. These results suggest that the G. thermodenitrificans SG-01 strain may be useful in the removal of nitrates and nitrites from wastewater generated as a result of livestock farming.

A water extract of Artemisia capillaris prevents 2,2'-azobis(2-amidinopropane) dihydrochloride-induced liver damage in rats.

A water extract of Artemisia capillaris Thunberg (Compositae) was investigated for protective effects against oxidative stress induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) in Sprague-Dawley male rats. Rats were orally administered A. capillaris water extract (ACWE; 7.5 g/kg) for 7 days before AAPH treatment (60 mg/kg). AAPH intoxication significantly elevated enzyme markers of liver injury (glutamic oxaloacetic transaminase and glutamic pyruvic transaminase). The pre-administration of ACWE significantly reduced the liver-damaging effects of AAPH as indicated by the low levels of these enzymes. Moreover, the ACWE administration significantly attenuated the accumulation of thiobarbituric acid-reactive substances in both plasma and liver tissues compared with those of rats administered AAPH alone. Furthermore, ACWE administration slightly improved the liver reduced glutathione levels and enhanced the production of antioxidant enzymes like catalase. A. capillaris contained 10.1 mg of catechin in 100 g of dried sample; the high-performance liquid chromatography results showed catechin composition in the ACWE to be 28% (-)-epigallocatechin gallate, 49% (-)- epigallocatechin, and 23% other catechins. These observations clearly indicate that ACWE contains antioxidant catechins capable of ameliorating the AAPH-induced hepatic injury by virtue of its antioxidant activity.