Gas Chromatographic Method for the Quantitative Determination of a Hydrolytic Degradation Impurity in Busulfan Injectable Products.

An efficient and stability-indicating method has been developed and validated for the quantitative determination of tetrahydrofuran (THF), a hydrolytic degradation impurity, in Busulfan injectable pharmaceutical products by using gas chromatograph equipped with a liquid autosampler and a flame ionization detector. The chromatographic separation was performed on a fused silica capillary (Stabilwax; 60 m length × 0.32 mm i.d., 0.5 µm film thickness) column. The methodology was validated in accordance with regulatory guidelines. The proposed method was found to be specific, stable, precise, linear, accurate, robust, and rugged in the concentration range from 4 to 1,080 ppm for THF. The developed method was successfully applied to determine the THF content in Busulfan injectable pharmaceutical products

The Nobel Prize in Chemistry 2004: 'ubiquitous' quality control of life

The Nobel Prize in Chem. for 2004 is shared by Aaron Ciechanover, Avram Hershko and Irwin Rose, who made fundamental discoveries concerning how cells regulate the breakdown of cellular proteins with extreme specificity. The three biochemists discovered ubiquitin-​mediated proteolysis, a process where an enzyme system tags unwanted proteins with many mols. of a small protein called ubiquitin and then sends then to the proteasome where they are broken down

Degradation of ethylbenzene by free and immobilized Pseudomonas fluorescens-CS2

Pseudomonas fluorescens-CS2 metabolized ethylbenzene as the sole source of carbon and energy. The involvement of catechol as the hydroxylated intermediate during the biodegradation of ethylbenzene was established by TLC, HPLC and enzyme analysis. The specific activity of Catechol 2,3-dioxygenase in the cell free extracts of P. fluorescens-CS2 was determined to be 0.428 μmoles min−1 mg−1 protein. An aqueous-organic, Two-Phase Batch Culture System (TPBCS) was developed to overcome inhibition due to higher substrate concentrations. In TPBCS, P. fluorescens-CS2 demonstrated ethylbenzene utilization up to 50 mM without substrate inhibition on inclusion of n-decanol as the second phase. The rate of ethylbenzene metabolism in TPBCS was found enhance by fivefold in comparison with single phase system. Alternatively the alginate, agar and polyacrylamide matrix immobilized P. fluorescens-CS2 cells efficiently degraded ethylebenzene with enhanced efficiency compared to free cell cultures in single and two-phase systems. The cells entrapped in ployacrylamide and alginate were found to be stable and degradation efficient for a period of 42 days where as agar-entrapped P. fluorescens was stable and efficient a period of 36 days. This demonstrates that alginate and polyacrylamide matrices are more promising as compared to agar for cell immobilization

In vitro selection of salt-tolerant Ailanthus altissimaSwingle

Salt-tolerant cell lines of Ailanthus altissima were selected from callus derived protoplasts. Murashige–Skoog (MS) liquid medium incorporated with various concentrations of NaCl was employed to enrich salt-tolerant A. altissima cell lines. Salt-resistant A. altissima cells were transferred on MS solid medium supplemented with 2.5 μM 2,4-dichlorophenoxy acetic acid (2,4-D), 0.5 μM benzyl adenine (BA) and various NaCl concentrations. The callus was cultured on MS medium containing NaCl for 5 months, to determine the survival rate as an index of salt tolerance. The measurement of growth parameters for salt-tolerant cells showed that the selected plant cell lines grew better than the unselected ones at all levels of NaCl tested. The salt-tolerant callus accumulated proline in correlation to the concentration of salts. Media supplemented with BA induced shoot differentiation of salt-resistant A. altissima cells

Enhanced production of tropane alkaloids in transgenic Scopolia parviflora hairy root cultures over-expressing putrescine N-methyl transferase (PMT) and hyoscyamine-6β-hydroxylase (H6H)

Scopolia parviflora adventitious roots were metabolically engineered by co-expression of the two gene putrescine N-methyl transferase (PMT) and hyoscyamine-6β-hydroxylase (H6H) cDNAs with the aid of Agrobacterium rhizogenes. The transformed roots developed into morphologically distinct S. parviflora PMT1 (SpPMT1), S. parviflora PMT1 (SpPMT2), and S. parviflora H6H (SpH6H) transgenic hairy root lines. Consequent to the introduction of these key enzyme genes, the production of the alkaloids hyoscyamine and scopolamine was enhanced. Among the transgenic hairy root lines, SpPMT2 line possessed the highest growth index. The treatment of transgenic hairy roots with growth regulators further enhanced the production of scopolamine. Thus, the results suggest that PMT1, PMT2, and H6H genes may not only be involved in the metabolic regulation of alkaloid production but also that these genes may play a role in the root development

Effect of supplementing terpenoid biosynthetic precursors on the accumulation of bilobalide and ginkgolides in Ginkgo biloba cell cultures

The effect of precursor feeding on the production of bilobalide and ginkgolides was studied with suspension cell cultures of Ginkgo biloba. The precursors greatly influenced the productivity of bilobalide and ginkgolides. Precursor supplementation increased the accumulation of both bilobalide and ginkgolides, and with positive effect on cell growth. The GA accumulation by cell cultures was influenced by precursors upstream in the metabolism, whereas the BB accumulation was under the influence of downstream precursors of the terpenoid biosynthetic pathway. Furthermore, precursor feeding modified the ratios of the BB, GA and GB in cells and cell cultures of G. biloba. The studies also aid in understanding effect of precursor feeding on the bilobalide and ginkgolides biosynthetic pathway. © 2005 Elsevier B.V. All rights reserved

Bacteral degradation of anthracene by Pseudomonas fluorescens KCP2

Pseudomonas fluorescens KCP2 species metabolized anthracene as the sole source of carbon and energy. Salicylic acid and Catechol were identified as few of the metabolic intermediates during the biodegradation of anthracene based on TLC and enzyme analysis. Pseudomonas fluorescens KCP2 cell free extracts exhibited salicylate hydroxylase and Catechol 1,2-dioxygenase enzymes with a specific activities of 0.34and 0.24 mmoles min-1mg-1 of protein respectively. The degradation rates were determined in the presence and in the absence of synthetic surfactants. The Pseudomonas fluorescens KCP1 species was immobilized in alginate and agar matrices. Both the matrices were stable with degradation ability for a period of 37 days and 31 days respectively. © Global Science Publications

Cyclooxygenase isoforms in health and disease

Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) have long been used for the treatment of pain and inflammation owing to their inhibitory effects on cyclooxygenase (COX). Ever since NSAIDs have been in use, multiple adverse effects have been noted. Assessment of many of these effects has been complicated due to the discovery of multiple splice variants of the COX gene, greater array of COX and specific COX-2 inhibitor availability. The effect of these drugs on COX cannot be readily explained. This has sparked a new field of investigation on splice variants of COX and effects of COX inhibitors. This review summarizes our current understanding of the role of cyclooxygenase in health and disease

An assessment of fluoride ecotoxicity biomarkers in earthworms

The increase in the fluoride levels of the ground water lead to fluorosis in humans. Environmental monitoring of fluoride toxicity is required to know the extent of pollution and its impact on the biodiversity. Earthworm can be developed as a model to study the effects of fluoride levels and the associated ecotoxicity. In this study three enzyme biomarkers in earthworm, Eudrilus eugenia, have been assessed. The fluoride LD50 value was found to be 3.32 g of NaF per Kg feed. All the biomarkers selected exhibited lower values in the presence of fluoride. The esterase (EST), acetyl cholinesterase (AChE) and catalase (CAT) activities were 42.08, 33.36 and 17.5 respectively. Thus these observations can be adopted as biomarkers for monitoring ecotoxicity of NaF in terrestrial and aquatic organisms. © Global Science Publications