Enhancement of Camptothecin Production in Nothapodytes nimmoniana, Graham., an Anticancerous Medicinal Plant: Current and Future Perspective

--P E Rajasekharan, V K Abdul Kareem and P Kavitha

Camptothecin (CPT), a monoterpene indole alkaloid, is one of the most promising anticancer drugs of the 21st century. It was shown to be effective in the complete remission of lungs, breast and uterine cervical cancers. Irinotecan and Topotecan, the two water soluble derivatives of CPT, have been approved by the FDA of the USA for treating colorectal and ovarian cancers. Although CPT has been reported to exist in several species, the highest concentration has been found in Nothapodytes nimmoniana, a small tree distributed in the Western Ghats of India. In spite of the rapid growth of the pharmaceutical industry, CPT is still extracted from plants. In the recent years, there has been an indiscriminate extraction of N. nimmoniana from many parts of India, especially from the Western Ghats because of the enormous demand for the chemical worldwide. Recently, some efforts have been initiated for the development of in vitro systems, conservation and production of CPT, identification of high-yielding individuals and molecular profiling. In this review article, we briefly outline the overall status of N. nimmoniana as a source of CPT and discuss the possibility of biotechnological intervention for higher production of CPT without destructive harvesting of natural population. Functional genomic approaches such as transcriptomics, proteomics and metabolomics will probably accelerate the identification of genes involved in CPT biosynthetic pathways. The combination of techniques like hairy root culture and metabolic engineering/physiological manipulation in N. nimmoniana seems to be the most attractive strategy for higher production of CPT.

© 2011 IUP. All Rights Reserved.

In Vitro Multiple Shoot Induction from Nodal Explants of Annona squamosa L.

-- R Balamurali Krishna, D Swapna, V Hymavathi,
R R Sujitha Reddy and K Jagadeeswara Reddy

Tissue culture studies were done in Annona squamosa—a plant of commercial importance—using nodal explants taken from matured plants. The number of shoots obtained from nodal explants was approximately 6-8 when cultured on MS medium containing BAP (2.5 mg/L). MS media supplemented with BAP showed favorable response in nodal explants. Multiple shoots formed after 2-3 weeks were separated and subcultured in the fresh medium of the same composition. Regenerated shoots were rooted on MS medium supplemented with IBA (0.1 mg/L). IBA was found to be more effective in root induction. The rooted plants were transferred to pots containing soil, cocopeat, and sand for hardening. The true-to-type plantlets of Annona squamosa were obtained within a short period of culture establishment. The present protocol is rapid, reproducible and less cumbersome over the conventional methods.

© 2011 IUP. All Rights Reserved.

Screening of Free-Living Nitrogen-Fixing Bacteria—Azotobacter and Associative Organisms by Molecular Techniques

-- V Kalaigandhi and S Kiruthika

Azotobacter is a free-living, diazotrophic bacteria commonly inhabiting aquatic and terrestrial environments. Molecular methodologies have been optimized and adapted to overcome traditional techniques. The new methodologies allow rapid access to microbial diversity and facilitate the discovery of new groups of microorganisms. The aim of the research was to screen the Azotobacter from marine water by molecular techniques. However, the total heterotrophic bacterial population (64 ´ 107 and 39 ´ 107) and Azotobacter population (47 ´ 102 and 30 ´ 102) were studied. The morphological differences of the isolates were also recorded, such as pale white, round, pin head colonies for sample O1; large, pale white, flat, slimy colonies for sample J10 and small, glistening, water drops like mucoid colonies for sample F9. The isolates, when subjected to the molecular studies, recorded that the DNA bands produced by the Azotobacter isolates were similar to that of the standard strain (lane 1). The 16s rRNA of Azotobacter using genus-specific oligonucleotide primers showed that the amplicon of the isolates (lanes 2, 3 and 4) were clear but lighter compared to the standard lane 1 which was thick. Since all the lanes scored the amplicon size of 1,080 bp, all were confirmed to be the members of Azotobacter sp. The associative organisms were also identified as Klebsiella and Pseudomonas by insilico analysis.

© 2011 IUP. All Rights Reserved.

Role of GST M1 and T1 Polymorphism in the Development of Myopia

-- Ch Hema Bindu, S Vishnupriya, A Sandhya,
K V Pavani and N Sunil Kumar

Robust economic growth is not possible without putting in place well-focused integrated programs to reduce poverty through empowering the people by increasing their access to the factors of growth, especially credit issues at the micro level. Bridging the gap between the potential demand for and the actual supply of microfinance services is a big challenge. In this paper, the growth and transformation of microfinance organizations has been discussed. The key context of the paper is how poor people can easily avail the microfinancial services under one umbrella in the fastest way. While discussing the factors and the theoretical position associated with innovation in microfinance, this paper has also brought out the missing link between the lender and borrower in the Indian context. As per the authors, filling of this gap is a precondition for poverty reduction on account of the influence of new paradigm of institutional viability under commercial microfinance.

© 2011 IUP. All Rights Reserved.