Screening bioactivities of Caesalpinia pulcherrima L. swartz and cytotoxicity of extract synthesized silver nanoparticles on HCT116 cell line.

The extract of Caesalpinia pulcherrima (C. pulcherrima) is one of the common herbal drugs which have a key role in treating pyretic, microbial infections, cancer and for several other traditional systems of treatment. In our present work, we demonstrate the bioactivities of extracts and cytotoxicity of synthesized silver nanoparticles on HCT116 cell line. The qualitative phytochemical tests indicated the presence of some adequately required metabolites as follows; the total phenolic content in the aqueous extract contains a higher amount of phenolic compounds (815 ±â€¯0.013 µgmg-1). The DPPH quenching activity of the aqueous extract showed an IC50 value of 18.7 µg which was equivalent to the IC50 value of ascorbic acid (15 µg) and methanolic extract (51 µg). The test extracts showed 4.6% haemolytic activity that attributes to its protective and non-toxic nature. The zone of inhibition of aqueous extract shown against the growth of E.coli was 25 mm. Further, silver nanoparticles synthesis was carried out with the extract and was characterized by X-ray diffraction, particle size analyzer, zeta potential, TEM- EDAX and UV spectroscopy. XRD analysis indicated the crystalline nature of silver nanoparticles with a face-centered cubic structure. The data obtained from the particle size analyzer demonstrated as 155.4 nm of the size of the synthesized silver nanoparticles. The values of zeta potential (-23.4 mV) revealed that the nanoparticles were extremely stable in colloidal form. SEM indicated the spherical shape of silver nanoparticles with the size range between 177.9 nm to 251.1 nm. Beside the efficient bioactivities, the synthesized C. pulcherrima silver nanoparticles showed significant cytotoxicity effect of 77.5% on a human colon cancer cell line. Therefore, along with antioxidant, antibacterial, haemolytic activity; C. pulcherrima also accomplished satisfactory cytotoxic property in anticancer mechanism as proven by this study.

Photocatalytic degradation of synthetic food dye, sunset yellow FCF (FD&C yellow no. 6) by Ailanthus excelsa Roxb. possessing antioxidant and cytotoxic activity.

The purpose of our work is to identify the bioactive compounds of bark and leaves extract from Ailanthus excelsa Roxb. and to explore its effectiveness against synthetic food dye. The presence of primary and secondary metabolites was confirmed by carrying out phytochemicals analysis. With the prior knowledge accessible on the indispensable secondary metabolites holding antioxidant and cytotoxicity activity, the quantitative screening of total phenolic and flavonoid content in methanolic and aqueous extract of bark and leaves from Ailanthus excelsa were done. Comparatively, a higher value of flavonoid (161±0.3µg/mg) and phenolic acid content (152.4±0.14µg/mg) was found in bark extract. By FTIR analysis, the characteristic peak was obtained at 1581.63 and 1598.99cm-1 confirmed the presence of functional groups associated to flavonoids and other phenolic groups respectively. In bark extract, 81% of DPPH inhibition was observed when compared to ascorbic acid (standard) 92% of free radical scavenging activity. Bark extract from Ailanthus excelsa exhibited 71% cytotoxicity against HeLa cell line (cervical cancer). In examining the toxicity level of crude extracts with red blood cells (RBC), the bark extract was showed a very less (2.8%) haemolytic activity. They also showed maximum zone of inhibition in antibacterial activity i.e. 13±0.5mm against Escherichia coli culture. At a concentration of 10mg/mL of crude extract from A. excelsa, 55% degradation of sunset yellow dye was observed. It concludes that, the compounds present in the A. excelsa, especially the bark extract showed better photocatalytic, haemolytic, antioxidant, cytotoxicity and antibacterial activity when compared to leaves extract.

Biosynthesis and characterization of copper oxide nanoparticles and its anticancer activity on human colon cancer cell lines (HCT-116).

The eco-friendly synthesis of nanoparticles through green route from plant extracts have renowned a wide range of application in the field of modern science, due to increased drug efficacy and less toxicity in the nanosized mediated drug delivery model. In the present study, our research groups have biosynthesized the stable and cost effective copper oxide nanoparticles (CuO NPs) from the leaves of (Ormocarpum cochinchinense) O. cochinchinense. The synthesis of crystalline CuO NPs from the leaf extract of O. cochinchinense were confirmed by various analytical techniques like UV-Visible Spectroscopy (UV-Vis), Fourier-Transform Infrared Spectroscopy (FT-IR), X-Ray Diffractometer (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Selected Area Electron Diffraction (SAED) pattern. Further the synthesized CuO NPs were screened for anticancer activity on human colon cancer cell lines (HCT-116) by MTT (3-(4,5-dimethyl-2-tiazolyl)-2,5-diphenyl-2-tetrazolium bromide) assay. The obtained result inferred that the synthesized CuO NPs demonstrated high anticancer cytotoxicity on human colon cancer cell lines (HCT-116) with IC50 value of 40µgmL-1 were discussed briefly in this manuscript.

Phyllanthus emblica seed extract mediated synthesis of PdNPs against antibacterial, heamolytic and cytotoxic studies.

Ecofriendly synthesis of Palladium nanoparticles (PdNPs) were achieved using Phyllanthus emblica (P. emblica) seeds as reducing agent. Further the ecofriendly synthesized PdNPs were subjected for various analytical techniques like UV-Vis, FT-IR, XRD, Zeta potential, SEM and TEM. The results indicated that green synthesized PdNPs were spherical in shape with average particle size of 28±2nm with moderate stability. Further the synthesized PdNPs and extract were subjected for its antibacterial studies against various disease causing pathogens by agar well diffusion method. Seed extract resulted in 8.9±1.46mm against B. subtilis and PdNPs showed 9.6±1.10mm against S. aureus and synthesized PdNPs and extract were tested for hemolytic which resulted in 20% and 10% respectively. Toxicity studies were done against Artemia salina (A. salina). The LC50 value of green synthesized P. emblica capped PdNPs and the P. emblica seed extract were found to be less toxic for A. salina with a value of 1.00µg/mL and 1.25µg/mL. In addition samples were checked for in vitro cytotoxicity assays on HeLa cell lines.

Synthesis and insecticidal activity of acridone derivatives to Aedes aegypti and Culex quinquefasciatus larvae and non-target aquatic species.

A serious Mosquito borne yellow fever is one of the grave diseases which affect the major population. Since there is no specific treatment for yellow fever, there is a necessity to develop an effective agent. The series of acridinone analogues 3 to 5 were synthesized with help of non-conventional microwave heating and confirmed by respective spectral characterization. 5c and 3b showed highest activity to kill 90% of larvae against A. aegypti and C. quinquefasciatus, respectively. Also the active products were treated to check the mortality of non-target aquatic species. Through the reports of the larvicidal bioassay, compounds 3b against C. quinquefasciatus whereas 5c against A. aegypti were found to be more active. By keeping this as a platform, further extension of the work can be done to find out a valuable drug for controlling disease vectors.

RSM optimized Moringa oleifera peel extract for green synthesis of M. oleifera capped palladium nanoparticles with antibacterial and hemolytic property.

Palladium nanoparticles (Pd NPs) are the very good catalytic agents in many coupling reactions, also these are very well biological agents against bacteria and fungus. M. oleifera capped Pd NPs were synthesized from microwave assisted methanolic extract of M. oleifera peel. To optimize the extraction process RSM (Response Surface Methodology) was applied. To get a good extraction yield BBD (Box-Behnken Design) was employed. The better optimized conditions for the extraction was found as 400W, 25mL of CH3OH at 65°C for 2min. We observed 61.66mg of extract yield from this method. Eco-friendly M. oleifera capped Pd NPs were synthesized using M. oleifera peel extract and confirmed using the different characterization techniques like UV- Vis spectroscopy, XRD, SEM and HR-TEM analysis. We found the size of the M. oleifera capped Pd NPs nanoparticles as 27±2nm and shape of the particles as spherical through the TEM analysis. M. oleifera capped Pd NPs exhibits good antibacterial activity against S. aureus (Staphylococcus aureus) and E. coli (Escherichia coli) bacterial strains and we found the zone inhibition as 0.6 and 0.7mm. The synthesized M. oleifera capped Pd NPs are screened for hemolytic activity and it proved the M. oleifera capped Pd NPs are non-toxic on RBCs cells.

Phenolic compounds in drumstick peel for the evaluation of antibacterial, hemolytic and photocatalytic activities.

Most of the wastes emitted from the food processing industries are not utilized for any further purpose. The economic value of the food waste is very less when compared to the collection or reuse or discard. To increase the economic value we have to design the food waste as useful product or applicable in most of the current field. Nothing is waste in this world with this concept we have investigated the phytochemical analysis of drumstick peel (Moringa oleifera). The result supports the presence of phenols, alkaloids, flavanoids, glycosides and tannins. Since various functional groups containing molecules are present in the extract; it has been further subjected to antibacterial and hemolytic activities. To analysis the antibacterial studies we have employed human pathogenic Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacterium. The result of antibacterial activity clearly shows that it possesses significant activity on both bacterial cultures. The hemolytic activity was performed on red blood cells (RBCs). From this result we observed that drumstick peel extract has been considered as non-toxic on RBCs. Malachite green was selected to perform photocatalytic activity. The results stated that the drumstick peel extract possessed good behaviour towards photocatalytic investigation. The malachite green was degraded upto 99.7% using drumstick peel extract.

Photocatalytic degradation of nitrophenol using biologically active Phyllanthus emblica seed extract.

The present study deals about the vicinity of phytochemicals present in the Phyllanthus emblica (P. emblica) seed extract. The bio-active compounds present in the methanolic seed extract have been identified using Gas Chromatography Mass Spectroscopy (GC-MS)·The antioxidant activity of P. emblica seed extract was evaluated using assistance of DPPH (2,2-Diphenyl-1-picrylhydrazyl) assay. The determination of total phenol and flavonoid substance were contemplated. Further blood clot lysis activity was also done to check the percentage of clot lysis in methanolic seed extract. The result proved that seed extract has potential application. The GCMS results of P. emblica suggest that Octyl-ß-d-Glucopyranoside is present in major quantity. The work has been designed towards the degradation of 2-nitrophenol and 4-nitrophenol using P. emblica methanolic seed extract. The progress of nitrophenol degradation has been observed in UV-visible spectroscopy. At 5min duration, the 4-nitrophenol has been degraded up to 82.42%. This may be due to the presence of secondary metabolites such as alkaloids, carbohydrate and phenols in the P. emblica seed extract. The seed extract showed good scavenging activity which resulted in IC50 value of 85.92µg/mL. The total phenol and flavonoid content present in the extract were 48.242 and 12.72mg/mL. Also the seed extract showed good lysis when compared to the standard streptokinase.

Photocatalytic and antibacterial properties of phytosynthesized CeO2 NPs using Moringa oleifera peel extract.

Biosynthetic methods are alternative approaches which are much safer than the normal techniques (physical and chemical) used for the methods for synthesis of metal nanoparticles. The benefits are sample as it is economic and environment friendly. Herein present investigation, we have reported a microwave mediated eco-friendly synthetic approach for preparing cerium oxide (CeO2) nanoparticles. Here, we used Moringa oleifera peel as the stabilizing and reducing agent towards synthesize of Ce2O NPs via microwave irradiation. The NPs were further characterized using UV-Vis, FT-IR, XRD and HR-TEM techniques. The FTIR analysis confirmed the phytochemical involvement in NPs stabilization. The crystallinity of CeO2 nanoparticles are well demonstrated through X-ray Diffraction and HR-TEM. The TEM images reveal the spherical shape of the CeO2 NPs having an average size of 45nm. Additionally, these CeO2 NPs were used successfully as a catalyst in the degradation of the dye, crystal violet. Also the antibacterial activity of the synthesized CeO2 NPs was evaluated using Staphylococcus aureus (Gram positive bacteria) and Escherichia coli (Gram negative bacteria). CeO2 NPs showed better activity on E. coli than S. aureus. We have demonstrated an eco-friendly preparation of CeO2 nanoparticles, a good photocatalyst and having better antibacterial properties.

Biotechnological aspects of ZnO nanoparticles: overview on synthesis and its applications.

The physicochemical methods of the synthesis of zinc nanoparticles (ZnO NPs) and some detailed studies on ZnO toxicity mechanism and biokinetics have been reported. However, some of these physical and chemical methods of synthesis are expensive and can also have toxic substances absorbed onto them. Hence, eco-friendly synthesis of nanoparticles due to their easier process, cheaper availability, and high stability is dominating new research. In particular, ZnO NPs which are now being synthesized through major biological systems involved in this are bacteria, fungi, and plant extracts; this has increased studies in various applications in the biological field. In this review, we have elaborated on various natural source-mediated syntheses of ZnO NPs and their role in various biological activities like antimicrobial, anticandidal, larvicidal, cytotoxic, and photocatalytic activities. Apart from these applications, ZnO NPs are also reported to help to prevent dust formation, for several years, on oil paintings.

Biotechnology and pharmacological evaluation of Indian vegetable crop Lagenaria siceraria: an overview.

Bottle gourd (Lagenaria siceraria) belongs to the family Cucurbitaceae, which comprises about 118 genera and 825 species. It is an important vegetable crop of India, and its production is influenced by a number of factors viz., environmental, nutritional, cultural operation and use of plant growth regulators. Since, bottle gourd belongs to a medicinal family, it plays a major role in the treatment of several diseases related to the skin and heart. There are several organic chemical compounds including vitamin B complex, pectin, dietary soluble fibres, ascorbic acid, beta-carotene, amino acids and minerals which have been isolated from this species. Therefore, the bottle gourd is considered to have a great impact on therapeutic health benefits. Due to drastic industrialization and urbanization, most of the human beings are facing several ill effects which may lead to death at extreme cases. Hence, the major research area was said to be nanotechnology. Taking into consideration, we have combined nanotechnology field with waste source in the name of green synthesis and planned to cure several diseases, as most of the researchers focused their work on this and succeeded too. The present study is a complete review of L. siceraria that covers the ethnomedical uses, chemical constituents, and pharmacological profile. This study is mainly focused on the antibacterial, hepatoprotective, diuretic and anthelminthic activities.

Green Synthesis of Silver and Titanium Dioxide Nanoparticles Using Euphorbia prostrata Extract Shows Shift from Apoptosis to G0/G1 Arrest followed by Necrotic Cell Death in Leishmania donovani.

The aim of the present study was to synthesize silver (Ag) and titanium dioxide (TiO2) nanoparticles (NPs) using green synthesis from aqueous leaf extract of Euphorbia prostrata as antileishmanial agents and to explore the underlying molecular mechanism of induced cell death. In vitro antileishmanial activity of synthesized NPs was tested against promastigotes of Leishmania donovani by alamarBlue and propidium iodide uptake assays. Antileishmanial activity of synthesized NPs on intracellular amastigotes was assessed by Giemsa staining. The leishmanicidal effect of synthesized Ag NPs was further confirmed by DNA fragmentation assay and by cell cycle progression and transmission electron microscopy (TEM) of the treated parasites. TEM analysis of the synthesized Ag NPs showed a spherical shape with an average size of 12.82 ± 2.50 nm, and in comparison to synthesized TiO2 NPs, synthesized Ag NPs were found to be most active against Leishmania parasites after 24 h exposure, with 50% inhibitory concentrations (IC50) of 14.94 µg/ml and 3.89 µg/ml in promastigotes and intracellular amastigotes, respectively. A significant increase in G0/G1 phase of the cell cycle with a subsequent decrease in S (synthesis) and G2/M phases compared to controls was observed. The growth-inhibitory effect of synthesized Ag NPs was attributed to increased length of S phase. A decreased reactive oxygen species level was also observed, which could be responsible for the caspase-independent shift from apoptosis (G0/G1 arrest) to massive necrosis. High-molecular-weight DNA fragmentation as a positive consequence of necrotic cell death was also visualized. We also report that the unique trypanothione/trypanothione reductase (TR) system of Leishmania cells was significantly inhibited by synthesized Ag NPs. The green-synthesized Ag NPs may provide promising leads for the development of cost-effective and safer alternative treatment against visceral leishmaniasis.

Synthesis and characterization of palladium nanoparticles using Catharanthus roseus leaf extract and its application in the photo-catalytic degradation.

The potential effect of Catharanthus roseus leaf extract for the formation of palladium nanoparticles and its application on dye degradation was discussed. The efficiency of C.roseus leaves are used as a bio-material for the first time as reducing agent. Synthesized palladium nanoparticles were supported by UV-vis spectrometry, XRD, FT-IR and TEM analysis. The secondary metabolites which are responsible for the formation of nanoparticles were identified by GC-MS. The results showed that effect of time was directly related to synthesized nanoparticles and functional groups has a critical role in reducing the metal ions and stabilizing the palladium nanoparticles in an eco-friendly process.

Biogenic-production of SnO2 nanoparticles and its cytotoxic effect against hepatocellular carcinoma cell line (HepG2).

In this paper, we have established for the first time, the terrific efficiency of aqueous extract of agricultural waste dried peel of sugar apple (Annona squamosa) in the rapid synthesis of stable SnO2 nanoparticles. In topical years, the deployment of secondary metabolites from plant extract has emerged as a novel technology for the synthesis of various nanoparticles. In this paper, we have studied the potential of SnO2 nanoparticles assembly using agricultural waste source for the first time. The synthesized nanoparticles were characterized and confirmed as SnO2 nanoparticles by using UV-visible spectroscopy, XRD, and TEM analysis. The motivation of this study was to examine cytotoxicity study of SnO2 nanoparticles against hepatocellular carcinoma cell line (HepG2). SnO2 nanoparticles inhibited the cell proliferation in a dose- and time-dependent manner with an IC50 value of 148 µg/mL. The treated cells showed an altered morphology with increasing concentrations of SnO2 nanoparticles. Our result shows that the SnO2 nanoparticles exhibit moderate cytotoxicity towards the hepatocellular carcinoma (HepG2) at tested concentrations.

Efficacy of larvicidal activity of green synthesized titanium dioxide nanoparticles using Mangifera indica extract against blood-feeding parasites.

Titanium dioxide nanoparticles (TiO2 NPs) are considered to be among the best photocatalytic materials due to their long-term thermodynamic stability, strong oxidizing power, and relative non-toxicity. Nano-preparations with TiO2 NPs are currently under investigation as novel treatments for acne vulgaris, recurrent condyloma acuminata, atopic dermatitis, hyperpigmented skin lesions, and other non-dermatologic diseases. The present study was to investigate the acaricidal and larvicidal activity of synthesized TiO2 NPs utilizing leaf aqueous extract of Mangifera indica L. (Anacardiaceae) against hematophagous parasites. The anti-parasitic activity of TiO2 NPs against the larvae of Rhipicephalus (Boophilus) microplus, Hyalomma anatolicum anatolicum and Haemaphysalis bispinosa (Acari: Ixodidae), fourth instar larvae of Anopheles subpictus, and Culex quinquefasciatus (Diptera: Culicidae) were assessed. The green synthesized TiO2 NPs were analyzed by UV-Vis, FTIR, X-ray diffraction (XRD), AFM, SEM, and TEM. The XRD analysis of synthesized TiO2 NPs revealed the dominant peak at 2θ value of 27.81 which matched the 110 crystallographic plane of the rutile structure indicating the crystal structure. The FTIR spectra exhibited a prominent peak at 3,448 cm(-1) and showed OH stretching due to the alcoholic group, and the OH group may act as a capping agent. The SEM images of TiO2 NPs displayed spherical, oval in shape, individual, and some in aggregates. Characterization of the synthesized TiO2 NPs using AFM offered three-dimensional visualization and uneven surface morphology. The TEM micrograph showed agglomerates, round and slight elongation with an average size of 30 ± 5 nm. The maximum efficacy was observed in synthesized TiO2 NPs against the larvae of R. microplus, Hyalomma anatolicum anatolicum, Haemaphysalis bispinosa, A. subpictus, and Culex quinquefasciatus with LC50 value of 28.56, 33.17, 23.81, 5.84, and 4.34 mg/L, respectively. In the present study, a novel, simple, and eco-friendly approach has been suggested to control blood-feeding parasites.

Photocatalytic action of AgCl nanoparticles and its antibacterial activity.

The scientific community is searching for biosynthetic methods for the production of metallic nanoparticles. Biogenic pathway has now become a vast developing area of research. A novel route biological synthesis of silver chloride nanoparticles (AgCI-NPs) using aqueous leaf extract of Morindacitrifolia under ambient conditions were evaluated. Synthesized nanoparticles were confirmed by UV-vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of pH on biosynthesis of AgCI-NPs were investigated using UV-vis spectroscopy. TEM images showed that the diameter of stable AgCI-NPs were approximately 12 nm. FTIR spectra provide the evidence for the presence of protein as possible biomolecules responsible for reduction and capping of nanoparticles. The synthesized AgCI-NPs were observed to have a good catalytic activity on the reduction of methylene blue (MB) dye by M.citrifolia extract which has been confirmed by decrease in absorbance maximum values of methylene blue with respect to time using UV-vis spectroscopy and was attributed to the electron relay effect.

Bioassay-guided isolation and characterization of active antiplasmodial compounds from Murraya koenigii extracts against Plasmodium falciparum and Plasmodium berghei.

Malaria is an overwhelming impact in the poorest countries in the world due to their prevalence, virulence and drug resistance ability. Currently, there is inadequate armoury of drugs for the treatment of malaria. This underscores the continuing need for the discovery and development of new effective and safe antimalarial drugs. To evaluate the in vitro and in vivo antimalarial activity of the leaf ethyl acetate extract of Murraya koenigii, bioassay-guided chromatographic fractionation was employed for the isolation and purification of antimalarial compounds. The in vitro antimalarial activity was assayed by the erythrocytic stages of chloroquine-sensitive strain of Plasmodium falciparum (3D7) in culture using the fluorescence-based SYBR Green I assay. The in vivo assay was done by administering mice infected with Plasmodium berghei (NK65) four consecutive daily doses of the extracts through oral route following Peter's 4-day curative standard test. The percentage suppression of parasitaemia was calculated for each dose level by comparing the parasitaemia in untreated control with those of treated mice. Cytotoxicity was determined against HeLa cells using MTT assay. Histopathology was studied in kidney, liver and spleen of isolated compound-treated Swiss albino mice. The leaf crude ethyl acetate extract of M. koenigii showed good in vitro antiplasmodial activity against P. falciparum. The in vivo test of the leaf crude ethyl acetate extract (600 mg/kg) showed reduced malaria parasitaemia by 86.6% against P. berghei in mice. Bioassay-guided fractionation of the leaf ethyl acetate extract of M. koenigii led to the isolation of two purified fractions C3B2 (2.84 g) and C3B4 (1.97 g). The purified fractions C3B2 and C3B4 were found to be active with IC50 values of 10.5 ± 0.8 and 8.25 ± 0.2 µg/mL against P. falciparum, and in vivo activity significantly reduced parasitaemia by 82.6 and 88.2% at 100 mg/kg/body weight on day 4 against P. berghei, respectively. The isolated fractions C3B2 and C3B4 were monitored by thin-layer chromatography until a single spot was obtained with R f values of 0.36 and 0.52, respectively. The pure compounds obtained in the present investigation were subjected to UV-visible spectroscopy, Fourier transformer infrared spectroscopy, 1D and 2D (1)H-Nuclear magnetic resonance (NMR), (13)C NMR, DEPT, COSY and Mass spectral analysis. Based on the spectral analysis, it is concluded that the isolated compounds were myristic acid (C3B2) and ß-caryophyllene (C3B4). The cytotoxic effect of myristic acid and ß-caryophyllene showed the TC50 values of >100 and 80.5 µg/mL, respectively against HeLa cell line. The histopathology study showed that protection against nephrotoxicity of kidney, hepatic damage of liver and splenocytes protection in spleen was achieved with the highest dose tested at 100 mg/kg/body weight. The present study provides evidence of antiplasmodial compounds from M. koenigii and is reported for the first time.

Green synthesis of silver nanoparticles using Alternanthera dentata leaf extract at room temperature and their antimicrobial activity.

A green rapid biogenic synthesis of silver nanoparticles AgNPs using Alternanthera dentata (A. dentata) aqueous extract was demonstrated in this present study. The formation of silver nanoparticles was confirmed by Surface Plasmon Resonance (SPR) at 430nm using UV-visible spectrophotometer. The reduction of silver ions to silver nanoparticles by A. dentata extract was completed within 10min. Synthesized nanoparticles were characterized using UV-visible spectroscopy; Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy and transmission electron microscopy (TEM). The extracellular silver nanoparticles synthesis by aqueous leaf extract demonstrates rapid, simple and inexpensive method comparable to chemical and microbial methods. The colloidal solution of silver nanoparticles were found to exhibit antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia and, Enterococcus faecalis.

Larvicidal activity of green synthesized silver nanoparticles using bark aqueous extract of Ficus racemosa against Culex quinquefasciatus and Culex gelidus.

OBJECTIVE: To investigate the larvicidal activity of synthesized silver nanoparticles (Ag NPs) utilizing aqueous bark extract of Ficus racemosa (F. racemosa) was tested against fourth instar larvae of filariasis vector, Culex quinquefasciatus (Cx. quinquefasciatus) and japanese encephalitis vectors, Culex gelidus (Cx. gelidus). METHODS: The synthesized Ag NPs was characterized by UV-vis spectrum, X-ray diffraction (XRD), Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR). The larvicidal activities were assessed for 24 h against the larvae of Cx. quinquefasciatus and Cx. gelidus with varying concentrations of aqueous bark extract of F. racemosa and synthesized Ag NPs. LC(50) and r(2) values were calculated. RESULTS: The maximum efficacy was observed in crude aqueous extract of F. racemosa against the larvae of Cx. quinquefasciatus and Cx. gelidus (LC(50)=67.72 and 63.70 mg/L; r(2)=0.995 and 0.985) and the synthesized Ag NPs (LC(50)=12.00 and 11.21 mg/L; r(2)=0.997 and 0.990), respectively. Synthesized Ag NPs showed the XRD peaks at 2 θ values of 27.61, 29.60, 35.48, 43.48 and 79.68 were identified as (210), (121), (220), (200) and (311) reflections, respectively. The FTIR spectra of Ag NPs exhibited prominent peaks at 3,425, 2,878, 1,627 and 1,382 in the region 500-3,000 cm(-1). The peaks correspond to the presence of a stretching vibration of (NH) C=O group. SEM analysis showed shape in cylindrical, uniform and rod with the average size of 250.60 nm. CONCLUSIONS: The biosynthesis of silver nanoparticles using bark aqueous extract of F. racemosa and its larvicidal activity against the larvae of disease spreading vectors. The maximum larvicidal efficacy was observed in the synthesized Ag NPs.

Efficient phyto-synthesis and structural characterization of rutile TiO2 nanoparticles using Annona squamosa peel extract.

In the present study, the biosynthesis of rutile TiO(2) nanoparticles (TiO(2) NPs) was achieved by a novel, biodegradable and convenient procedure using fruit peel Annona squamosa aqueous extract. This is the first report on the new, simple, rapid, eco-friendly and cheaper methods for the synthesis of rutile TiO(2) NPs at lower temperature using agricultural waste. Rutile TiO(2) NPs were characterized by UV, XRD, SEM, TEM and EDS studies. The UV-Vis spectrophotometer results were promising and showed a rapid production of TiO(2) NPs with a surface plasmon resonance occurring at 284 nm. The formation of the TiO(2) NPs as observed from the XRD spectrum is confirmed to be TiO(2) particles in the rutile form as evidenced by the peaks at 2θ=27.42°, 36.10°, 41.30° and 54.33° when compared with the literature. The TEM images showed polydisperse nanoparticles with spherical shapes and size 23±2 nm ranges.