The potential of recently isolated bacteria Paenibacillus larvae for the effective decolorization of Indigo carmine was evaluated. The effects of operational parameters (temperature, pH, dye concentration, shaking/non shaking) were tested. Maximum extent of decolorization was observed when the medium was incorporated with 10 g/l of yeast extract and peptone. Decolorization was strongly inhibited at non-shaken conditions as well as incorporation of inorganic sources (sodium nitrite and ammonium chloride) in the medium. Maximum decolorization was observed at 30 degrees C (100%) and 40 degrees C (92%) at 8 h of incubation. The LC-MS and NMR analysis confirms the oxidation of Indigo carmine . The primary degradation products were found to be Isatin sulfonic acid and anthranilicacid.

Nanocrystalline CrN coatings, widely required for surface engineering application covering wear and corrosion resistance, need to be investigated for atomic scale morphology, surface roughness, local stiffness, phase uniformity, and homogeneity. Evolution of these properties as a function of thickness need to be studied. In this paper, we have attempted to address these issues through use of a multimode scanning probe microscope (SPM) equipped to carry out Atomic Force Microscopy (AFM) and Atomic Force Acoustic microscopy (AFAM) of Chromium nitride films (100-500 nm thick) on Si prepared under high vacuum by pulsed Laser Ablation using Nd-YAG Q-switched laser. Prior to SPM analysis, the coatings were annealed in N2 atmosphere at 700 degrees C for 30 minutes for improving crystallanity and coating substrate adhesion. The GIXRD patterns of these annealed specimens showed formation of nanocrystalline CrN. Also signature of amorphous phases was seen. The grain size was estimated to be less than 30 nm. Contact mode AFM imaging revealed a roughness value less than 50 nm. Local stiffness values were calculated from AFM force-distance curves. Imaging of frictional force and surface flaws are being investigated by Frictional Force Microscopy (FFM), resonance spectroscopy, and AFAM, respectively. The contrast in AFAM images is seen due to variation in surface elasticity in reference and CrN samples. Stiffness constant and elastic modulus were calculated for both the samples and compared.

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INTRODUCTIONTridax procumbens (family-Asteraceae) is commonly known as "Ghamra". In English it is popularly called as "coat buttons" because of the appearance of the flowers. It has been extensively used in Ayurvedic system of medicine for various illnesses. It is a well known medicine for liver disorders.1 This plant extract know to express various pharmacologically active compounds which has been shown to have roll in immunomodulatory, hypoglycemic, hepatoprotective action. It was also shown antioxidant, anti-inflammatory, analgesic, anti-arthritic and wound healing effect and have been used as a skeletal muscle relaxant.2-9 The phytochemical screening of the different plant parts like leaf, stem, flower and root of Tridax have revealed the presence of alkaloids, flavonoids (catechins and flavones) and tannins. 10,11 Phytochemicals are chemical compounds, created or biosynthesized through the usual metabolic pathways in the plants. These chemicals are often referred to as secondary metabolites. These secondary metabolites have no direct activity in the primary metabolic cycles, such as photosynthesis, respiration, transpiration and mineral metabolism etc. But they have been proved to have major roles in the stress tolerance and defense mechanisms.12 Secondary metabolites are important for the plants interactions such as plant-pollinator, plant-pathogen and plant-herbivore. These are classified into three major classes (alkaloids, terpenoids and phenolics) and habitually colored, aromatic and tasty compounds.13 They are also used in signaling and regulation of primary metabolic pathways. Secondary metabolites are used by many pharmaceuticals, agrochemicals, biopesticides, flavoring, coloring agents, and as food additives.14 The biosynthesis of secondary metabolites is controlled by various factors such as genetics and ecological factors. 15The quantity of secondary metabolites in medicinal plants is strongly dependent on the growing conditions and synthesis is regulated by external environmental stimuli 16 Abiotic factors such as high and low temperatures, drought, alkalinity, salinity of the soil, ultraviolet radiation stresses have been known as more potential factors for manipulating and promoting the accumulations of secondary metabolites in medicinal plants. [17][18][19] The abiotic factors of the growing area such as soil fertility, local geoclimate, humidity, light and temperature, seasonal changes and cultivation techniques, have also been shown to impact on the metabolism and synthesis of the secondary metabolites. 20 Hence the aim of the study to investigates the habitats influences on in-vitro antioxidant activities and the quantity of phytochemical (total phenol, flavonoid and tannin) variations in leaves and flowers of Tridax. MATERIALS AND METHODS Plant materialsTridax leaves and flowers were collected from the three different habitats:-1. Kolli-Hills (is a mountain situated in the Ester Ghats in Namakkal district of Tamil, Nadu India. The mountains are about 1000 to 1300 m in altitude and cover a...

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