Synthesis and Characterization of Silver Nanoparticles Using Cannonball Leaves and Their Cytotoxic Activity against MCF-7 Cell Line

Cannonball (Couroupita guianensis) is a tree belonging to the family Lecythidaceae. Various parts of the tree have been reported to contain oils, keto steroids, glycosides, couroupitine, indirubin, isatin, and phenolic substances. We report here the synthesis of silver nanoparticles (AgNPs) using cannonball leaves. Green synthesized nanoparticles have been characterized by UV-Vis spectroscopy, SEM, TEM, and FTIR. Cannonball leaf broth as a reducing agent converts silver ions to AgNPs in a rapid and ecofriendly manner. The UV-Vis spectra gave surface plasmon resonance peak at 434 nm. TEM image shows well-dispersed silver nanoparticles with an average particle size of 28.4 nm. FTIR showed the structure and respective bands of the synthesized nanoparticles and the stretch of bonds. Green synthesized silver nanoparticles by cannonball leaf extract show cytotoxicity to human breast cancer cell line (MCF-7). Overall, this environmentally friendly method of biological silver nanoparticles production provides rates of synthesis faster than or comparable to those of chemical methods and can potentially be used in various human contacting areas such as cosmetics, foods, and medical applications

Genetic algorithm based reactive power dispatch for voltage stability improvement,

a b s t r a c t Voltage stability assessment and control form the core function in a modern energy control centre. This paper presents an improved Genetic algorithm (GA) approach for voltage stability enhancement. The proposed technique is based on the minimization of the maximum of L-indices of load buses. Generator voltages, switchable VAR sources and transformer tap changers are used as optimization variables of this problem. The proposed approach permits the optimization variables to be represented in their natural form in the genetic population. For effective genetic processing, the crossover and mutation operators which can directly deal with the floating point numbers and integers are used. The proposed algorithm has been tested on IEEE 30-bus and IEEE 57-bus test systems and successful results have been obtained

Role of Sulphated Polysaccharides from in the Control of Diet-Induced Hyperlipidemia and Associated Inflammatory Complications in Rats

Hypercholesterolemia and associated cardiovascular complications continue to occur in a great number of people. However, certain coastal populations have lower incidence of cardiovascular and other diseases, which may be attributed to regular intake of seaweeds in their diet. Seaweeds contain sulphated polysaccharides (SPS) which demonstrate a wide spectrum of biomedical properties and are phytochemical analogues of mammalian heparin sulphate. This knowledge served as the major impetus for exploring the therapeutic potential of SPS from the brown algae Sargassum wightii and SPS from Fucus vesiculosus in experimental rats against diet-induced hyperlipidemia and associated inflammatory complications. Adult male Wistar rats were divided into six groups with six rats in each. The control group (group I) was left untreated while group II rats were fed with a high cholesterol diet (CCT diet – normal rat chow with 4% cholesterol, 1% cholic acid and 0.5% thiouracil) for 14 days. Rats in groups III and IV received SPS from S. wightii (SW group) and SPS from F. vesiculosus (FV group) (5mg/kg b.wt/day, subcutaneously) during the last 7 days, respectively. Rats in groups V and VI were fed with a high cholesterol diet for 14 days and in addition were given SPS from S. wightii (CCT + SW group) and SPS from F. vesiculosus (CCT + FV group) at the weight of 5mg/kg b.wt/day, subcutaneously during the last 7 days, respectively. The adverse effects of hypercholesterolemia were evident from increased levels of serum lipid status and inflammatory complications manifested by augmented levels of plasma tumour necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP), fibrinogen, inducible nitric oxide synthase (iNOS), nitric oxide (NO), cyclooxygenase (COX-2) and lysosomal enzymes. Treatment with algal SPS considerably restored the above abnormalities. SPS from S. wightii and SPS from F. vesiculosus were almost equally effective in mitigating hypercholesterolemia and related inflammatory complications

Multi-Objective Genetic Algorithm for voltage stability enhancement using rescheduling and FACTS devices

This paper presents the application of Multi-Objective Genetic Algorithm to solve the Voltage Stability Constrained Optimal Power Flow (VSCOPF) problem. Two different control strategies are proposed to improve voltage stability of the system under different operating conditions. The first approach is based on the corrective control in contingency state with minimization of voltage stability index and real power control variable adjustments as objectives. The second approach involves optimal placement and sizing of multi-type FACTS devices, Static VAR Compensator and Thyristor Controlled Series Capacitor along with generator rescheduling for minimization of voltage stability index and investment cost of FACTS devices. A fuzzy based approach is employed to get the best compromise solution from the trade off curve to aid the decision maker. The effectiveness of the proposed VSCOPF problem is demonstrated on two typical systems, IEEE 30-bus and IEEE 57 bus test systems

SYNTHESIS AND CHARACTERIZATION OF SILVER NANOPARTICLES USING TABERNAEMONTANA DIVARICATA AND ITS CYTOTOXIC ACTIVITY AGAINST MCF-7 CELL LINE

Objective: Tabernaemontana divaricata a common garden plant on tropical countries has been used as a traditional medicine. There is an increasing commercial demand for nanoparticles due to their wide applicability in various areas such as electronics, catalysis, chemistry, energy, and medicine. Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are quite often toxic and flammable. In this work, we describe a cost effective and environment friendly technique for green synthesis of silver nanoparticles (AgNPs) from T. divaricata leaf extract. Methods: Biosynthesized AgNPs were characterized using UV– Vis absorption spectroscopy, TEM, FTIR and SEM analysis. Cytotoxicity of AgNPs was tested in human breast cancer cell line (MCF-7). Results: TEM analysis showed the average particle size of 22.85 nm as revealed in their structure. The qualitative assessment of reducing potential of leaf extract has also been carried out which indicated presence of significant amount of reducing entities. Green synthesized AgNPs by T. divaricata leaf extract show cytotoxicity to human breast cancer cell line (MCF-7). Conclusion: The most important outcome of this work will be the development of value-added products from T. divaricata. The characteristics of the obtained AgNPs were analysed which could be used potentially in various human contacting areas such as cosmetics, foods, and medical applications