Studies on north indian volvocales-III. Fertilization in Eudorina californica (shaw) goldstein

The present communication deals with the details of sexual reproduction including the process of fusion of gametes in Eudorina californica (Shaw) Goldstein (earlier described as E. indica lyengar). The present observations are compared with those on other species in which the process of fusion was recorded.     

Differential methods of inoculation of plant growth-promoting rhizobacteria induce synthesis of phenylalanine ammonia-lyase and phenolic compounds differentially in chickpca

Foliar spray and micro-injection of plant growth-promoting rhizobacterial species, viz. Pseudomonas fluorescens and P. aeruginosa on chickpea induced synthesis of phenylalanine ammonia-lyase (PAL) when tested against Sclerotinia sclerotiorum. Induction of PAL was also associated with increased synthesis of phenolic compounds such as tannic, gallic, caffeic, chlorogenic and cinnamic acids. Treatment with P. fluorescens was found to be more effective in inducing phenolic compounds as compared to P. aeruginosa. However, persistence of PAL activity was observed more with P. aeruginosa. Although both the inoculation methods were effective, foliar application was found to be superior to micro-injection in terms of rapid PAL activity leading to the synthesis of phenolic compounds.     

Anti-viral triterpenes: a review

Phytochemistry Reviews - Triterpenes are naturally occurring derivatives biosynthesized following the isoprene rule of Ruzicka. The triterpenes have been reported to possess a wide range of...     

Rapid repair of hepatic DNA damage induced by camptothecin in the intact rat

Administration of camptothecin (7,14 or 28 mg per 100 g body wt.) to rats intraperitoneally, induced single strand breaks in hepatic DNA. Fragmentation of liver DNA on alkaline sucrose gradients was noted within 5 minutes and reached a maximum by 30 to 60 minutes after the administration of the drug. By about 4 hours, the DNA damage was almost completely repaired. However, using neutral sucrose gradients, significant fragmentation of DNA could not be seen. The rapid repair of the liver DNA in vivo induced by camptothecin, a cancer chemotherapeutic agent, is interesting in view of the long delay in the repair of the DNA damage induced by several chemical carcinogens in an intact animal (9,10).     

Degradation of pyrene by an enteric bacterium, <Emphasis Type=Italic>Leclercia adecarboxylata</Emphasis> PS4040

A newly discovered enteric bacterium Leclercia adecarboxylata PS4040, isolated from oily sludge contaminated soil sample was reported for degradation of polycyclic aromatic hydrocarbons (Appl Environ Microbiol 70:3163–3166, 2004a). This strain could degrade 61.5% of pyrene within 20 days when used as sole source of carbon and energy. The time course degradation experiment detected several intermediate products and the metabolites were identified by gas chromatography mass spectrometry analysis. Metabolite I was the detected on the 5th day and was identified as 1-hydroxypyrene and was detected till 10th day. Metabolite II which was detected on 10th day was identified as 1,2-phenanthrenedicarboxylic acid. Metabolite III and Metabolite IV were identified as 2-carboxy benzaldehyde and ortho-phthalic acid, respectively and were detected in the culture broth on 10th and 15th day. 1,2-benzene diol (catechol) was the fifth metabolite detected in the culture extracts on the 15th day and was subsequently reduced on day 20. Identification of Metabolite I as 1-hydroxypyrene was further investigated as this intermediate was not previously reported as a ring oxidation product for degradation of pyrene by bacterial strains. Purification by preparative high performance liquid chromatography and nuclear magnetic resonance spectroscopy, confirmed the identification of Metabolite I as 1-hydroxypyrene. L. adecarboxylata PS4040 could also use 1-hydroxypyrene as a sole source of carbon and energy. Thus a probable pathway for degradation of pyrene by enteric bacterium is proposed in this study, with 1-hydroxypyrene as initial ring oxidation product.