Preparation and characterization of hybrid chitosan-silver nanoparticles (Chi-Ag NPs); A potential antibacterial agent.

In this study, a novel ecofriendly chitosan- silver nanoparticles hybrid was developed. Biological method using leaf extract of T. portulacifolium was used as reducing agent for its synthesis and the antibacterial efficiency of these hybrid nanoparticles were evaluated against the bacteria E. coli and S. marcescens organisms. The intense peak observed around 419 nm in the UV-Vis indicates the formation of silver nanoparticles. The XRD analysis showed that the hybrid chitosan-silver nanoparticles have a polycrystalline and face-centered cubic configuration. FTIR spectrum hybrid chitosan-silver nanoparticles indicated speaks vibration of NH and OH. The EDS analysis confirmed the presence of Ag, O, C and N elements in the prepared sample. The spherical shape was obtained from TEM analysis and it indicated that with average particles around 3.24 nm to 44.80 nm. The prepared hybrid chitosan-silver nanoparticles showed significant antibacterial activities against E. coli and S. marcescens. In addition, the surface membrane damages and surface morphology of test pathogens were visualized using FESEM analysis.

Surface active gold nanoparticles biosynthesis by new approach for bionanocatalytic activity.

In the present day, nanotechnology is one of the most promising leading scientific and potentials areas in modern key technology development toward to the humankind. The synthesis of noble metal nanoparticles (NPs) is an expanding research area due to the possible applications for the development of bio-medical applications. Eco-friendly approach for the biosynthesis of gold nanoparticles (AuNPs) using the aqueous extract from Ruellia tuberosa and Phyllanthus acidus (leaf and twig) for the first time. Surface active AuNPs were characterized by UV-Vis spectroscopy, FTIR (Fourier transform infrared) spectroscopy, DSC (differential scanning colorimetry), DLS (dynamic light scattering) and environmental SEM (scanning electron microscope) analysis at room temperature (RT). Enhanced surface plasmon resonance (SPR) absorbance UV visible optical spectra were detected in the range of 552, 548, 558 and 536 nm. SEM and DLS (transmission mode) analysis confirmed the morphology of the nanoparticles to be spherical with the average size in the range of 88.37, 94.31, 82.23 and 81.36 nm. Further they have enhanced the enzyme activity on α-amylase, cellulase, and xylanase. The results suggest that the phyto-fabricated AuNPs from R. tuberosa and P. acidus is simple, less expensive, eco-friendly, green synthesis and also can be exploited for the potential future industrial and bio-medical applications.

Isolation and identification of antibacterial compound from the leaves of Cassia auriculata.

OBJECTIVES: Antimicrobial properties of medicinal plants and plant parts such as flowers, roots, fruits, seeds and oils are being used to cure some chronic and acute diseases throughout the world. In the present study, an attempt has been made to isolate and identify the antibacterial compound present in the leaves of the Cassia auriculata. MATERIALS AND METHODS: A preliminary screening of antibacterial activity was carried out with fine different plant extracts viz., Aegle marmelos, Chloris Virgata, Clausena anisata, Feronia limonia and Cassia auriculata against different human pathogenic bacteriae such as Escherichia coil, Salmonella typhi, Proteus mirabilis and Klebsiella pneumoniae at different concentrations. RESULTS AND CONCLUSIONS: Based on the results, the plant Cassia auriculata was selected as the efficient plant, which shows antibacterial activity against the tested organisms. Further compound responsible for its antibacterial activity was isolated and identified by IR spectrum, 1HNMR, 13CNMR and Mass spectrum studies, as oleanolic acid, which has the molecular formula of C30H48O3.

Effect of different level and source of copper supplementation on immune response and copper dependent enzyme activity in lambs.

An experiment was conducted on 30 male Nellore lambs with average body weight (BW) of 15.45 +/- 0.06 kg to determine the level of the copper (Cu) supplementation in diet from inorganic and organic sources required for optimum immunity and its effect on copper dependent enzymes by allotting them randomly to five groups in completely randomized design. The dietary treatments were viz., basal diet (no Cu supplementation, BD), other four groups were offered BD supplemented with 7 or 14 ppm Cu from copper sulphate (CuSO(4)) and Cu-proteinate, respectively. The lambs were fed the respective diets at 3.5 per cent BW to meet the requirements except Cu for 180 days. The humoral immune response against Brucella abortus and chicken RBC was assessed after 90 days of feeding. The in vivo delayed type hyper sensitivity reaction against PHA-P and in vitro lymphocyte proliferation against Con A indicative of cell mediated immune response (CMI) was assayed at 180 days of feeding. At the end of experiment four lambs from each group were slaughtered for estimation of liver superoxide dismutase activity (SOD). The ceruloplasmin and RBC-SOD activities were higher (P < 0.05) in 14 ppm Cu supplemented lambs from Cu-proteinate at 90 and 180 days, while the liver SOD activity was higher (P < 0.05) in lambs fed 14 ppm Cu from CuSO(4). The STAT titres against B. abortus were higher in Cu supplemented lambs, with no effect of dose of supplementation. Lambs supplemented with Cu-proteinate had higher titers than CuSO(4) on 7 and 14 days of post sensitization. The total immunoglobulin concentration and the CMI response against PHA-P and Con-A was higher (P < 0.05) in lambs fed 14 ppm Cu-proteinae diet. The IgM level was though high in Cu supplemented lambs, no dose or source effect were observed. The study indicated that Cu dependent enzymes activity and immune response were highest and respond better against stress in lambs on 14 ppm supplemented Cu from Cu-proteinate.

In Vitro Organogenesis of Lycianthes bigeminata Bitter.

Lycianthes bigeminata Bitter (Solanaceae) is an important medicinal herb distributed in the sholas of Nilgiris and chiefly used for curing ulcer. It is reported that the species is present in the sholas with poor population size in comparison to other constituent species. Owing to the demand and subsequent exploitation, it is predicted that it may occupy still poor association in the sholas of Nilgiris in course of time. Hence in vitro regeneration through employing tissue culture technique is needed. The preliminary attempt in the present study reports that the MS medium supplemented with Benzyl Amino Purine (BAP) and Naphthalene Amino Acid (NAA) at 0.5 mg/l each, induced effective callus formation. However further studies on hardening is suggested to know the survivability of this species.

Effects of copper sulfate and copper nitrate in aquatic medium on the restoration potential and accumulation of copper in stem cuttings of the terrestrial medicinal plant, Portulaca oleracea linn.

The stem cuttings of the terrestrial, ornamental plant, Portulaca oleracea, grew well in distilled water by producing adventitious roots and leaves. However, when exposed to various concentrations of sulfate and nitrate salts of copper resulted in a suppression of root growth, increase in initiation time of roots and sprouts and decay of stem cuttings from the cut open end, decrease in number of leaves with an increase in concentration of copper in the growth medium. Accumulation of copper increased with increasing concentrations of both copper sulfate and copper nitrate. However, copper accumulation was greater in copper nitrate than in copper sulfate treatment. Hence, copper in the presence of nitrate is more toxic than in the presence of sulfate. The accumulation factors in all treatment concentrations were greater than 1, hence P. oleracea is a copper accumulator.