Glutathione regulates enzymatic antioxidant defence with differential thiol content in perennial pepperweed and helps adapting to extreme environment

Perennial pepperweed (Lepidium latifolium Linn.) is a preferred ‘phytofood’ that is available for the longest period of a year in Ladakh. Present study was undertaken to identify the mechanism of redox homeostasis and understand factors responsible for its biochemical superiority during low temperatures. Results reveal that despite the stressful environment at higher altitude, the cellular conditions are more reducing for this plant. The reducing environment is maintained by significant induction of GSH rather than changes in its oxidation state, which changes the redox potential by 12 mV. Lower ratio of NADP⁺/NADPH and induction of new antioxidative isozymes at Leh (3,505 m) suggest crucial role of redox regulation in adaptation. These new proteins have higher thiol content and could provide an efficient redox sensing mechanism in Lepidium latifolium that respond through GSH/NADPH redox buffers. In vitro feeding experiment suggested that GSH plays an important role in induction of antioxidant enzymes, which may not be the direct consequence of H₂O₂ accumulation. It needs to be further investigated whether its responsive redox metabolism has some role in its invasive growth in riparian plains of America.     

Paclobutrazol Induces Photochemical Efficiency in Mulberry (Morus alba L.) Under Water Stress and Affects Leaf Yield Without Influencing Biotic Interactions

Journal of Plant Growth Regulation - Mulberry (Morus spp.) is an important plant used for rearing silkworm (Bombyx mori L.). Its fruit is also used for human consumption with several medicinal...     

Evaluation of Nutritional and Antioxidant Status of Lepidium latifolium Linn.: A Novel Phytofood from Ladakh

Lepidium latifolium Linn. (perennial pepperweed) is one of the preferred phytofoods among cold arid region of Ladakh, India and its leaves contribute significantly to people''s diet. This study was conducted to determine its nutritive value and antioxidant activity. Plant samples from three different locations were selected in the present study. Results showed that this plant is an excellent source of glucosinolates, notably sinigrin that is present in very high amount (∼70–90%). Its value ranged from 149 to 199 µg per g fresh weight. Fatty acid composition analysis showed that its leaves were abundant in unsaturated fatty acids, specifically linolenic acid (18∶3) whose percentage is about 50%. Higher glucose and crude protein along with higher nitrogen to sulfur ratio, supplements the nutritive value of this plant. Based on total phenol, flavanoids, free radical scavenging activity and DNA protective activity showed that this ecotype of perennial pepperweed contains high antioxidant properties. The percentage inhibition for O₂ ⁻ scavenging activity ranged from 41.3% to 83.9%. Higher content of phenols (26.89 to 50.51 mg gallic acid equivalents per g dry weight) and flavanoids (38.66 to 76.00 mg quercetin equivalents per g dry weight) in leaves could be responsible for the free radical scavenging activity of this plant. Depending upon the location of the plants, variations were observed in different activities. Based on the systematic evaluation in this study, preparations of Lepidium latifolium from Ladakh can be promoted as substitute to dietary requirements.     

Antimalarials from nature

Malaria is a major public health problem mainly due to the development of resistance by the most lethal causative parasitic species, Plasmodium falciparum to the mainstay drugs like chloroquine. New drugs with unique structures and mechanism of action are urgently required to treat sensitive and drug-resistant strains of malaria. Historically, compounds containing novel structure from natural origin represent a major source for the discovery and development of new drugs for several diseases. This review presents recent advances in antimalarial drug discovery from natural sources, including plant extracts, and compounds isolated from plants, bacteria, fungi and marine organisms. These compounds offer new and novel scaffolds for development as antimalarials. The literature from 1998 to October 2008 is reviewed. The review present literature compilation from plant and marine extracts, alkaloids (naphthylisoquinolines, bisbenzylisoquinolines, protoberberines and aporphines, indoles, manzamines, and miscellaneous alkaloids) terpenes (sesquiterpenes, triterpenes, diterpenes, and miscellaneous terpenes) quassinoids, flavonoids, limonoids, chalcones, peptides, xanthones, quinones and coumarines, and miscellaneous antimalarials from nature. The review also provides an outlook to recent semisynthetic approaches to antimalarial drugs discovered from natural sources.     

Energy aware scheduling of deadline-constrained tasks in cloud computing

Energy efficiency is the predominant issue which troubles the modern ICT industry. The ever-increasing ICT innovations and services have exponentially added to the energy demands and this proliferated the urgency of fostering the awareness for development of energy efficiency mechanisms. But for a successful and effective accomplishment of such mechanisms, the support of underlying ICT platform is significant. Eventually, Cloud computing has gained attention and has emerged as a panacea to beat the energy consumption issues. This paper scrutinizes the importance of multicore processors, virtualization and consolidation techniques for achieving energy efficiency in Cloud computing. It proposes Green Cloud Scheduling Model (GCSM) that exploits the heterogeneity of tasks and resources with the help of a scheduler unit which allocates and schedules deadline-constrained tasks delimited to only energy conscious nodes. GCSM makes energy-aware task allocation decisions dynamically and aims to prevent performance degradation and achieves desired QoS. The evaluation and comparative analysis of the proposed model with two other techniques is done by setting up a Cloud environment. The results indicate that GCSM achieves 71 % of energy savings and high performance in terms of deadline fulfillment.