Characterization of superoxide production from aldehyde oxidase: an important source of oxidants in biological tissues

Aldehyde oxidase, a molybdoflavoenzyme that plays an important role in aldehyde biotransformation, requires oxygen as substrate and produces reduced oxygen species. However, little information is available regarding its importance in cellular redox stress. Therefore, studies were undertaken to characterize its superoxide and hydrogen peroxide production. Aldehyde oxidase was purified to >98% purity and exhibited a single band at approximately 290 kDa on native polyacrylamide gradient gel electrophoresis. Superoxide generation was measured and quantitated by cytochrome c reduction and EPR spin trapping with p-dimethyl aminocinnamaldehyde as reducing substrate. Prominent superoxide generation was observed with an initial rate of 295 nmol min(-1) mg(-1). Electrochemical measurements of oxygen consumption and hydrogen peroxide formation yielded values of 650 and 355 nmol min(-1) mg(-1). In view of the ubiquitous distribution of aldehydes in tissues, aldehyde oxidase can be an important basal source of superoxide that would be enhanced in disease settings where cellular aldehyde levels are increased.     

Antimycobacterial activities of novel 2-(sub)-3-fluoro/nitro-5,12-dihydro-5-oxobenzothiazolo[3,2-a]quinoline-6-carboxylic acid

Various 2-(sub)-3-fluoro/nitro-5,12-dihydro-5-oxobenzothiazolo[3,2-a]quinoline-6-carboxylic acid derivatives were synthesized from 2-aminothiophenol by a five-step reaction, evaluated for in-vitro and in-vivo antimycobacterial activities against Mycobacterium tuberculosis H37Rv (MTB), multi-drug resistant Mycobacterium tuberculosis (MDR-TB), and Mycobacterium smegmatis (MC2), and also tested for the ability to inhibit the supercoiling activity of DNA gyrase from M. smegmatis. Among the thirty-four synthesized compounds, 2-(3-(diethylcarbamoyl)piperidin-1-yl)-)-3-fluoro-5,12-dihydro-5-oxobenzothiazolo[3,2-a]quinoline-6-carboxylic acid (7l) was found to be the most active compound in vitro with MIC of 0.18 and 0.08 microM against MTB and MTR-TB, respectively. Compound 7l was found to be 2 and 570 times more potent than isoniazid against MTB and MDR-TB, respectively. In the in-vivo animal model 7l decreased the bacterial load in lung and spleen tissues with 2.78 and 3.12-log10 protections, respectively, at the dose of 50 mg/kg body weight.     

Effect of Fe-Pd bimetallic nanoparticles on Sphingomonas sp. PH-07 and a nano-bio hybrid process for triclosan degradation

In this study, we have evaluated the effect of palladium-iron bimetallic nanoparticles (nFe-Pd) on diphenyl ether (DE) degrading bacterial strain Sphingomonas sp. PH-07 as well as a sequential nano-bio hybrid process with nFe-Pd as catalytic reductant and PH-07 as biocatalyst for degradation of triclosan. Strain PH-07 grew well in the presence of nFe-Pd up to 0.1 g/L in minimal salts medium with DE as carbon source. In aqueous system, TCS (17.3 μM) was completely dechlorinated within 2 h by nFe-Pd (0.1 g/L) with concomitant release of 2-phenoxyphenol (16.8 μM) and chloride ions (46 μM). All possible dichloro- and monochloro-2-phenoxyphenol intermediates were identified by HPLC and GC-MS analyses, and the dechlorination pathway was proposed. Addition of PH-07 cells into the reactor effectively degraded the 2-phenoxyphenol. Our results reveal that strain PH-07 survives well in the presence of nFe-Pd and nFe-Pd/PH-07 hybrid treatment could be a potential strategy for degradation of TCS.     

Application of ozone on induction of resistance in Vigna unguiculata cv. Co 6, against Fusarium wilt

Abstract

The efficacy of ozone in controlling Fusarium oxysporum, the casual agent of wilt disease, was evaluated in Vigna unguiculata (cowpea). Different concentrations of ozone (T₁, T₂, T₃, T₄ and T₅) were passed to the Vigna unguiculata seedlings among which T₃ treatment reduced Fusarium wilt more effectively than other treatments by enhancing growth promotion along with the activation of the defense-related enzymes than other treatments. T₃ treatment provokes enhanced biomass production along with increased activity of chitinase, β-1,3-glucanase, peroxidase and phenylalanine ammonia-lyase than other treatments relative to control seedlings. Moreover, this is the first report of ozone protecting seedlings against Fusarium wilt of Vigna unguiculata plants.     

Cyclooxygenase-2 enzyme inhibitory triterpenoids from Picrorhiza kurroa seeds

A bioassay guided phytochemical study of the ethyl acetate extract of the seeds of Picrorhiza kurroa afforded a new triterpenoid, 2alpha, 3beta, 19beta, 23-tetrahydroxyolean-12-en-28-O-beta-D-glucoside (1), along with five known triterpenoids, 2alpha, 3beta, 19beta, 23-tetrahydroxyolean-12-en-28-oic acid (2), 2alpha, 3beta, 23-trihydroxyolean-12-en-28-O-beta-d-glucoside (3), 2alpha, 3beta, 23-trihydroxyolean-12-en-28-oic acid (4), 2alpha, 3beta, 19beta, trihydroxyolean-12-en-28-oic acid (5), and 2alpha, 3beta, 6beta, 23-tetrahydroxyolean-12-en-28-oic acid (6). Their structures were established by extensive NMR spectral studies. The acetyl derivatives, compounds 7 and 8, were prepared from compounds 1 and 2, respectively, to aid in their structure elucidation. The inhibition of cyclooxygenase-2 (COX-2) enzyme by compounds 1--6 at 100 microg/mL was 38.3%, 39%, 37%, 49.6%, 25%, and 45.0%, respectively. However, compounds 1--6, at 100 microg/mL, did not inhibit cyclooxygenase-1 (COX-1) enzyme. Compound 1 is a novel triterpenoid and compounds 1--6 are isolated for the first time from the seeds of P. kurroa.     

Seasonal changes in carbohydrates of perennial root nodules of beach pea

Seasonal changes in amyloplast, starch, total soluble sugars, non-reducing sugars and reducing sugars of perennial root nodules of beach pea (Lathyrus maritimus) were studied. Ultrastructural changes in nodule cells of beach pea indicated an accumulation of large amounts of amyloplasts with multiple starch grains in summer months. As the winter season sets in, degradation of amyloplasts and starch grains was detected. The membranes of amyloplasts faded out in winter and the structure of the amyloplasts was lost. The degradation of starch grains showed some electron-dense fiber-like material and amorphous structures. Quantitative data revealed an increase in starch reserves during the summer and depletion during the winter. Total soluble sugar and non-reducing sugar concentrations peaked in the middle of the winter, whereas reducing sugar concentrations showed an increase in the fall. These results indicate that elevated levels of various sugars most likely help to maintain high osmolarity of cells so that the dormant nodules do not freeze during the prolonged periods of cold in the winter.     

Interaction of antiprogestins with progesterone receptors in rat uterus

Cytosolic and nuclear progesterone receptors (PRc and PRn) under antiprogestin treatment were measured in rat deciduoma and compared with values for contralateral (nondeciduomatous) rat uterine tissue. Uterine PRc and PRn of the progesterone treated group were 101 +/- 8.7 and 4770 +/- 590 fmol/mg DNA respectively. After treatment with antiprogestins STS-557, 5 alpha-DNE, (5 alpha-dihydronorethisterone), 5 alpha-DNG (5 alpha-dihydronorgestrel), RU-22092 and RU-16556, PRc in the nondeciduomatous control horn ranged from 127 to 377 fmol/mg DNA and PRn from 2785 to 17925 fmol/mg DNA. In the decidual tissue, PRc decreased significantly (4.6 +/- 0.8 fmol/mg DNA) on 5 alpha-DNG treatment as compared with the progesterone alone treatment group (147 +/- 3.8). PRn in decidual tissue also decreased maximally on 5 alpha-DNG treatment. These results suggest that the interaction of antiprogestins may not be identical in control uterine tissue and in deciduoma.     

Analeptic agent from microbes upon cyanide degradation

Applied Microbiology and Biotechnology - Microbes being the initial form of life and ubiquitous in occurrence, they adapt to the environment quickly. The microbial metabolism undergoes alteration...