UV-Vis Spectrophotometer Analysis Research Articles

Effective Remediation Strategy for Xenobiotic Zoxamide by Pure Bacterial Strains, Escherichia coli, Streptococcus pyogenes, and Streptococcus pneumoniae.

Zoxamide, a class IV hazardous fungicide, is perilous for the environment due to its highly persistent nature. Up till the current date, there are no reports on the biodegradation of zoxamide. The scarcity of knowledge in this domain led to the present research to evaluate the biodegradation of this benzamide fungicide by three bacterial strains, Escherichia coli (EC), Streptococcus pyogenes (SPy), and Streptococcus pneumoniae (SP). Biotransformation of zoxamide was scrutinized in nutrient broth assemblies for a period of 28 days followed by UV-visible spectrophotometer and GC-MS analysis of the metabolites. The results exhibited a low to medium biodegradation potential of the bacterial cells to metabolize zoxamide. The highest biotransformation percentage was observed by E. coli to be 29.8%. The order of half-life calculated for the degradation results was EC (42.5) < SPy (58.7) < SP (67.9) days. GC-MS analysis indicated the formation of several metabolites including, 2-(3,5-dichloro-4-methylphenyl)-4-ethyl-4-methyl-4H-1,3-oxazin-5(6H)-one, 3,5-dichloro-N-(3-hydroxy-1-ethyl-1-methyl--2-oxopropyl)-4-methylbenzamide and 3,5-dichloro-4-methylbenzamide. The research could influence the biotreatment strategies for the environmentally friendly eradication of xenobiotics.

Photocatalytic, antibacterial and anticancer activity of silver-doped zinc oxide nanoparticles

Silver-doped zinc oxide nanoparticles (Ag-ZnO NPs) were successfully synthesized by the Sol-gel method coated with polyethylene glycol as a stabilizing and capping agent. The UV–Vis spectrophotometer analysis was done to analyze the optical property of the nanoparticles. XRD pattern showed the hexagonal structure of ZnO nanoparticles and the reduction in the intensity of the peaks of Ag-ZnO NPs indicates the incorporation of Ag+ ions in the ZnO lattices. The surface structural properties of the NPs were confirmed by Field Emission Scanning Electron Microscope (FE-SEM), High Resolution Transmission Electron Microscopy (HRTEM) and Selected Area Electron Diffraction (SAED). The elemental composition of nanoparticles was confirmed by EDAX and XRF-Spectroscopy. The functional group of ZnO and Ag nanoparticles were determined by FT-IR spectroscopy. The photocatalytic activity of Ag-ZnO NPs was studied against ponceau and the maximum degradation percentage was observed to be 89% at 140 min. Further, Ag-ZnO NPs unveiled high potent antibacterial activity against the selected bacterial pathogens and it also rendered significant anticancer activity in UVB-induced HaCaT cells. Consequently, the fluorescent microscopic analysis confirmed the increasing Reactive Oxygen Species (ROS) generation and Mitochondrial Membrane Potential (MMP) loss in the HaCaT cells that leads to the apoptosis induction. Hence, the selected combination of nanoparticles has proven to exhibit higher photocatalytic, antibacterial and anticancer activity. In the near future, it could be an efficient tool for eradicating the dye pollution from wastewater and also preferably be utilized in the cosmetics and pharmaceutical industries to prevent skin cancer.

Development and Characterization of Nanoparticles-Loaded Bio-composites for Biomedical Settings

There is a dire need to engineer biologically robust constructs to meet the growing needs of 21st-century medical sector. The increasing (re)-emergence of human-health related pathogenic microbes has caused a havoc and serious challenge to health care services. In this context, herein, we report the development and characterization of various polymeric bio-composites with unique structural and functional attributes. For a said purpose, chitosan and graphene were used to engineer bio-composites, which were then functionalized by loading silver and platinum nanoparticles. A microwave-assisted approach was adopted to construct silver and platinum nanoparticles loaded graphene-based bio-composites. While, “one-pot” synthesis approach was used to engineer silver and platinum nanoparticles loaded chitosan-based bio-composites. As developed bio-composites were designated as GO-Ag-S1 to GO-Ag-S5 (silver nanoparticles loaded graphene-based bio-composites), GO-Pt-P1 to GO-Pt-P5 (platinum nanoparticles loaded graphene-based bio-composites), CHI-Ag-S1 to CHI-Ag-S5 (silver nanoparticles loaded chitosan-based bio-composites), and CHI-Pt-P1 to CHI-Pt-P5 (platinum nanoparticles loaded chitosan-based bio-composites). Finally, the nanoparticles loaded bio-composites of graphene and chitosan were subjected to characterization via UV-Visible spectrophotometric analysis, percent loading efficiency (%LE) analysis, Fourier-transform infrared (FTIR) spectroscopy, mechanical measurements, and antibacterial attributes. The UV-Visible spectrophotometric analysis revealed characteristic peaks appeared at the λmax 420 nm and 266 nm which belongs to the silver and platinum nanoparticles, respectively. The graphene-based bio-composites, i.e., GO-Ag-S3, GO-Ag-S4, and GO-Pt-P3 showed optimal %LE of 88, 92, and 89%, respectively. Whereas, CHI-Ag-S4, CHI-Pt-P3, and CHI-Pt-P4 bio-composites showed optimal %LE of 94, 86, and 94%, respectively. Two regions, i.e., (1) between 3600-3100 cm-1, and (2) between 1,800 and 1,000 cm-1 in the FTIR spectra were found of particular interest. The FTIR profile exposed the available functional moieties at the surface of respective bio-composites. Variable mechanical attributes of silver and platinum nanoparticles loaded bio-composites were recorded from the stress-strain curves. All developed bio-composites showed bactericidal activities up to certain extent against both test strains. As compared to the initial bacterial cell count (control value, i.e., 1.5 × 108 CFU/mL), the bio-composites with higher %LE showed almost complete inhibition, with a log reduction from 5 to 0, and bactericidal activities up to certain extent against both test strains, i.e., Bacillus subtilis (B. subtilis), and Escherichia coli (E. coli). In conclusion, the notable structural, functional, mechanical and antimicrobial attributes suggest the biomedical potentialities of newly in-house engineered silver and platinum nanoparticles loaded graphene and chitosan-based bio-composites.

Chromatographic and Spectrophotometric Determination of Some Phenolic Compounds in Tridax procumbens Linn Stem

Phenolic compounds are copious secondary metabolites found in Tridax procumbens plant which is traditionally known for its antimicrobial activities. This research work is aimed at determining major phenolic compounds present in the stem of T. procumbens with their amounts. The phenolic compounds present in T. procumbens stem were separately extracted in methanol and ethanol. The total phenolic contents and the total flavonoid contents present were determined by UV–visible spectrophotometric analysis using Folin–Ciocalteu and Folin–Denin methods respectively. Gas chromatographic–mass spectrometric (GC–MS) analysis was used to identify and quantify some of the phenolic compounds present in the stem of T. procumbens. The total phenolic contents of methanolic and ethanolic extracts by spectrophotometric analysis were 52.8 mg gallic acid/g extract and 163.8 mg gallic acid/g extract respectively, while the total flavonoid contents were 19.9 mg rutin/g and 3.5 mg rutin/g respectively. The GC–MS analysis of the methanolic and ethanolic extracts showed the presence of four phenolic compounds with their respective concentrations, namely thymol (1.78 and 1.52 mg/g), eugenol (49.64 and 49.88 mg/g), gallic acid (0.34 and 0.52 mg/g) and isobutyl gallate (2.88 and 63.32 mg/g). The result obtained from the Folin-Ciocalteu and GC–MS revealed that the ethanolic extract (166.7 mg/g of gallic acid), has more phenolic content than the methanolic extract (54.64 mg/g of gallic acid). The ethanolic extracts showed greater ability of extraction for phenolic compounds from T. procumbens.

NANOCRYSTALLINE SnO2/TiO2 FOR SOLAR CELLS APPLICATION

The developments in the field of solar cells need to create a new material to improve the electrical properties, which leads to an increase in conversion efficiency. So, in this paper, nanocrystalline Tin dioxide (SnO2) as a thin film were synthesized and deposited on Titanium dioxide using chemical Spray pyrolysis thechniqe (CSPT). The mixed aqueous solution of Tin chloride (SnCl2) was prepeared at room temperature using magnatic stirr and sprayted on glass slide at 300 °C. Our results indicated that the prepared films are smooth, homogeneous and have good adhesion to the substrate. The results of structural properties revealed that the synthesis films are polycrystalline in nature with prefer orientations (110) and (101) for SnO2 and TiO2 respectively. The optical properties results using UV-Vis spectrophotometer analysis shows that high transmittance (grater than 70 %) and wide optical energy gap 3.97, 3.93 and 3.88 eV for TiO2, SnO2 and SnO2/TiO2 respectivly.

Impact of Physical Attributes on Proficient Phytosynthesis of Silver Nanoparticles Using Extract of Fresh Mulberry Leaves: Characterization, Stability and Bioactivity Assessment

Application of green chemistry towards phytosynthesis of nanoparticles has gained attention of environment friendly world due to its simple, rapid, stable, eco-friendly and cost-effective property. But there are limitations to this growing interest, as the dimension and geometry of nanoparticles produced through phytosynthesis often varies greatly. To overcome the problem, current study deals with the assessment of reducing effect of the plant extract at different light intensity, pH and temperatures. Current study reports that the optimal condition for phytosynthesis of silver nanoparticles was neutral pH (pH 7), 25 °C and diffuse light (230 lx). It was observed that rapid synthesis of silver nanoparticles takes place with increase in light intensity, alkalinity and temperature, as revealed by quick appearance of dark brown colouration on addition of extract. But rapid synthesis leads to the formation of large size particles with increase in polydispersity as revealed from TEM analysis and were found to be instable through zeta potential analysis. It was observed that at acidic pH nanosilver formation does not takes place, while at low temperature it takes more time for nanosilver formation, but both conditions were found to be unstable. Nanosilver formed at neutral pH and 25 °C under diffuse light gives the size dimension of 18.11 ± 2.55 and 18.94 ± 5.30 nm with zeta potential of + 36.4 and + 37.4 mV respectively indicating stability, besides that they were found to be stable under long storage condition as revealed by UV–Visible spectrophotometric analysis. Silver nanoparticles formed under optimized condition of pH 7 and at 25 °C were found to be bioactive as it showed potentiality to extend the shelf life of post harvest mulberry leaves by 7 days.

Green synthesis of Ag and Pd nanoparticles for water pollutants treatment.

Silver (Ag) and palladium (Pd) nanoparticles were synthesized via a green synthesis route, which was mediated with the extract of Daucus carota leaves. The morphological, crystalline and structural nature of the synthesized nanoparticles was characterized by UV-Vis spectrophotometer, and TEM, XRD and FT-IR analyses. High antibacterial activities of the prepared Ag and Pd nanoparticles were observed towards different water-borne pathogens of Klebsiella pneumonia, Vibrio cholera and Escherichia coli. The catalytic efficiency of the prepared nanoparticles for the removal of rhodamine 6G (Rh-6G) dye was also evaluated. Nearly 98% of the Rh-6G dye was decolorized by the synthesized Pd nanoparticles within 2 min, and the synthesized Ag nanoparticles took 30 min for 89.4% decolorization. This work provided greener nanocatalysts for pollutant treatment and demonstrated the power of green biosynthesis for metallic nanoparticles.

Remote Investigation of Total Chromium Determination in Environmental Samples of the Kombolcha Industrial Zone, Ethiopia, Using Microfluidic Paper-based Analytical Devices.

Microfluidic paper-based analytical devices (μ-PADs) fabricated in Japan were employed for the determination of total chromium (Cr) in water, soil, and lettuce irrigated with wastewater in Ethiopia. The μ-PADs, which were printed by wax printing in Japan, were transported to Ethiopia and prepared for the determination of total Cr by adding appropriate reagents to the pretreatment and detection zones. Soil and lettuce samples were determined by the μ-PADs and a UV-Vis spectrophotometer in Ethiopia. A paired t-test showed that the mean total Cr concentrations determined in the soil and lettuce samples were not significantly different between μ-PADs and UV-Vis spectrophotometric analysis at the 5% level of significance. This implies that the μ-PADs have good accuracy and reliability, and could be employed to monitor Cr in environmental samples. We found that the total Cr concentrations in all soil and lettuce samples were above the permissible limit. Moreover, evaluating Cr contamination level using the geo-accumulation index indicated that the soils were contaminated with Cr moderately to heavily. Thus, the present work successfully demonstrated the potential of remote investigations of pollution in a less-equipped laboratory by transporting the μ-PADs fabricated in another laboratory.

BIOLOGICAL SYNTHESIS OF SILVER NANOPARTICLES USING VICIA FABA EXTRACT AND ASSESSING ITS ANTIBACTERIAL ACTIVITY

The biological method provides a simple and efficient route for the synthesis of silver nanoparticles (AgNPs). The present study was aimed to synthesize AgNPs using Viciafaba seed extract as a reducing agent, which is a cost-effective, safe and eco-friendly method. The advantage of selecting this plant is that the phenolic and flavonoid compounds present in these seeds exhibit reducing property. Synthesized nanoparticles were characterized by using UV-Visible spectroscopy, Fe-SeM and X-ray diffractometer (XRD). Fe-SeM images showed that the particles were in the range of 12-22nm and flower structured. The formation and stability of AgNPs were confirmed by UV–vis spectrophotometer analysis, which showed higher absorbance at 430nm. XRD studies revealed a high degree of the crystalline structure of nanoparticles and a face-centered cubic structure. The anti-bacterial potency was tested against Escherichiacoli and Clostridium perfringens. These silver nanoparticles synthesized byV.faba seed extract exhibited the highest antibacterial effect against E.coli than C. perfringens.

Biomediated Green Synthesis of Copper Nanoparticles using Piper nigrum Leaf Extract

In the present days the development of efficient green synthesis of metal nanoparticles has become a major focus of researchers. It was aimed in order to find a safe, economic and eco-friendly technique for the production of well characterized nanoparticles. The present study reports the green synthesis of copper nanoparticles using plant extract (pepper leaf extract) and a copper salt (copper chloride, CuCl2). Copper nanoparticles are produced by the reduction of CuCl2, while the aqueous leaf extract act as reducing agent. The formation of copper nanoparticles was recognized by the change of colour from blue to black. The synthesized nanoparticles were then characterized through EDAX, XRD, and UV-Vis spectrophotometry. EDAX confirmed the formation of copper nanoparticles. The UV-Vis spectrophotometer analysis confirmed the absorption peak of copper nanoparticles at wavelength of 500-700 nm. XRD analysis revealed three sharp peaks specifically referred to face centered cubic structure of metallic copper. This work was also carried out the optical studies of copper nanoparticles which were exposed to direct sunlight. This study reflected the effect of sunlight intensity on the absorption peak of copper nanoparticles.

Chiral coordination polymers based on a new d-ribose derivative ligand: Syntheses, structures and probe functions

Three coordination polymers (CPs) {[CuL2Br]Br·6H2O}∞ (1), {[CuL2Cl2]·2.5CH3OH·3.5H2O}∞ (2) and {[NiL2(NO3)2]·CH3CN·3CH3OH·H2O}∞ (3) were prepared using a new d-ribose derivative ligand L (L = 1,2,3,4-tetrakisisoniacyl-β-l-ribopyranose). X-ray single crystal analysis revealed that 1–3 all crystallized in the triclinic P1 space group, all the CPs have 1-D metallomacrocycle strand structures, all the L ligands in the CPs show the same chiral type, and there are four pyridyls bonding with each metal centre arranged into a Δ-propeller configuration in all the three CPs. The same chiral type of the space group and the same chiral type of the propellers should be determined by the same chiral type of the L ligands. In addition, the slightly soluble powders of 1 and 2 displayed probe functions of detecting cysteine, glutathione and N-acetyl cysteine in UV–Vis spectrophotometric analysis of suspensions, which extended the application of UV–Vis spectrophotometry into suspension systems of micron particles.

Effects of hydrothermal treatment on the morphology and photocatalytic efficiency of TiO2 nanofiber

This research aims to prepare titanium oxide nanofiber using a simple electrospinning procedure, then study the effect of hydrothermal treatment on the morphology and photocatalyst of nanofiber. The produced TiO2 nanofiber is characterized by XRD, FESEM, PL and UV-vis spectrophotometer analysis. XRD measurements show that the produced TiO2 nanofiber includes two phases, anatase and rutile in addition to the change in the percentage weight of these two phases after hydrothermal treatment. FESEM images reveal that there is a change in the nanofiber’s morphology by the formation of tetragonal nanorods on the surface of pure nanofiber after the hydrothermal treatment. The efficiency of TiO2 nanofiber has been studied before and after the hydrothermal treatment. The photocatalytic efficiency evaluated by photodegradation of methylene blue under UV light irradiation which shows that the efficiency of TiO2 nanofiber after hydrothermal treatment (97.7%) after a degradation time 180 min was higher than that before hydrothermal (92%).

Antimicrobial resistance modulation of MDR E. coli by antibiotic coated ZnO nanoparticles

We evaluated three types of total six preparations against multidrug resistant E. coli i) three antibiotic coated ZnO nanoparticles (gentamicin coated nanoparticle-GNp; chloramphenicol coated nanoparticles-CNp; and both gentamicin & chloramphenicol coated nanoparticle-GCNp), ii) ZnO nanoparticle alone-Np, and iii) two antibiotics used in single (Gentamicin-G; and Chloramphenicol-C). A total of n = 200 sub-clinically positive mastitic milk samples of bovine origin were processed for isolation of MDR E. coli using microbiological and clinical laboratory & standard institute's protocols. ZnO Nps were prepared from zinc acetate dihydrate (Zn (CH3COO)2. 2H2O), polyethylene glycol (C2nH4n+2On+1), and urea (CH₄N₂O) by standard chemical protocol. Nps were characterized by XRD and STEM analyses while coating of antibiotics on Nps was confirmed by UV–Visible spectrophotometric analysis. Analysis of variance and student t-test were applied at 5% probability using SPSS version 22 statistical software for inferences on obtained data. There was significantly (p < 0.05) lowest minimum inhibitory concentrations (MICs) and highest zone of inhibitions (ZOIs) in case of GCNp (10.42 ± 4.51 μg/mL & 22.00 ± 1.00 mm) followed by GNp (20.79 ± 8.95 μg/mL & 20.00 ± 1.00 mm) and then CNp (25.96 ± 8.95 μg/mL & 12.33 ± 0.57 mm). Percentage increase in ZOI were expressed as 135.8, 78.43, and 312.76% by GCNp when compared with that of G, C, and Np, respectively. GNp and CNp coated preparations exhibited 114.36 and 275.73% increase in ZOI than to that of G and C, respectively. Similar trend was found in percentage reduction of MICs of preparations. Highest filamentation, indicator of bacterial damage, of E. coli was noted at MIC of GCNp followed by GNp and CNp. The study concluded antibiotic coated ZnO nanoparticles significant candidates modulating antibiotic resistance in MDR E. coli.

Green Synthesis of Silver Nanoparticles From Solenostemon Monostachyus Leaf Extract and In Vitro Antibacterial and Antifungal Evaluation

A rapid green synthesis of silver nanoparticles (AgNPs) using plant extract Solenostemo monastachyus (S. monastachyus) with silver nitrate is reported here. The formation of AgNPs was confirmed by a colour change in the plant extract from pale yellow to reddish brown and was further characterized by UV-Vis spectrophotometric, FT-IR, SEM, EDX and XRD analyses. Ag+ ions were reduced by the phytochemicals present in the extract. A characteristic single broad peak was observed at 450 nm and has been ascribed to the excitation of surface plasmon resonance phenomenon. The efficient capping and stabilization properties of the NPs were revealed by the FT-IR analysis. SEM and XRD results showed the formation of spherical shaped AgNPs with the average particle size of less than 100 nm and EDX confirmed the presence of silver in the prepared AgNPs. The antimicrobial properties of the biosynthesized AgNPs was evaluated against some selected bacterial and fungal species. The prepared AgNPs had notable antimicrobial activity against the selected bacterial and fungal species. Thus, the biosynthesized AgNPs could be a good lead for antimicrobial agent.

Biogenic Synthesis of Zinc Oxide Nanoparticles by Bryophyllum pinnatum and its Acute Oral Toxicity Evaluation in Wistar Rats.

The evaluation of toxic effects of nanoparticles (NPs) has become an important aspect of Nanotechnology research in the 21st century. The present investigation deals with the green synthesis of biogenic zinc oxide nanoparticles (ZnO-NPs) using Bryophyllum pinnatum leaves, their characterization and evaluation of acute oral toxicity in Wistar rats. The characterization of synthesized ZnO-NPs revealed maximum absorbance at 307 nm on UV-Vis spectrophotometric analysis, NTA showed mean size of particles and mode of the particles distribution as 128.2 nm and 12.6 nm, respectively. Zeta potential was found to be -0.369 mV. The absorbance shown by FTIR at 3469, 1644, 1355 and 887 cm-1 indicates the involvement of biomolecules that are accountable for capping and stabilization of ZnO-NPs. The XRD assessment further demonstrated the crystalline nature of the ZnO-NP. The TEM analysis of the synthesized ZnO-NPs revealed the presence of spherical NPs with the mean size of 3.7 nm. The acute oral toxicity evaluation in rat showed an approximate median lethal dose to be more than 2000 mg/kg body weight. It is thus concluded that biogenic ZnO-NPs showed absence of acute oral toxicity symptoms at the doses employed in the present study.

Highly selective and sensitive tool for the detection of Hg(II) using 3-(Trimethoxysilyl) propyl methacrylate functionalized Ag-Ce nanocomposite from real water sample.

Mercury and its derivates cause distinct toxicity and it is detrimental to the ecosystem where the excessive concentration contributes towards the environmental pollutants. The current study reported a colorimetric method for the detection of Hg(II) ion with high specificity and selectivity using Ag-Ce nanocomposite (NC) functionalized by 3-(Trimethoxysilyl) propyl methacrylate. The synthesized Ag-Ce NC was characterized by using double beam UV-visible spectrophotometer, zeta sizer, EDS, TEM, FT-IR, XRD and particle size analyzer. The synthesized particle possessed an average particle size of 27 ± 1 nm and zeta potential of -39.32 ± 3 mV. The brownish yellow colored Ag-Ce NC changed to colorless in presence of Hg(II) where the colorimetric detection was extremely specific and superior towards Hg(II) ion on comparing the tests with other metal ions. An excellent linear correlation was observed between absorbance (395 nm) and Hg(II) concentrations (1 nM-10 μM) (R2 = 0.988) with LOD of 0.03 nM. A cotton swab based probe was prepared for selective, elegant and low cost colorimetric method to detect Hg(II). The parametric study was performed for optimizing the suitable condition. The colorimetric probe developed by this study for Hg(II) detection using Ag-Ce NC shows excellent practical applicability.

Biofabricated SnO2 nanoparticles using Red Spinach (Amaranthus tricolor L.) extract and the study on photocatalytic and electrochemical sensing activity

Biofabrication of SnO2 nanoparticles (SnO2 NPs) using Amaranthus tricolor L.) extract has been conducted. Synthesis of the nanoparticles was conducted by refluxing tin chloride dihydrate as SnO2 precursor followed by calcination at 400 °C. The formation of SnO2 NPs was identified from UV-Visible spectrophotometric analysis and particle size analyzer. The resulting materials were characterized by x-ray diffraction (XRD), Fourier-Transform Infra-Red (FTIR), scanning electron microscope-energy dispersive x-ray (SEM-EDS), transmission electron microscope (TEM), and diffuse reflectance UV-Visible (UV-DRS). Photocatalytic evaluation of SnO2 NPs was carried out in a photodegradation of bromophenol blue (BPB) under photocatalytic and photooxidation mechanism with the presence of H2O2. Physicochemical analyses confirm the formation of SnO2 NPs providing the capability to act as photoactive material. The photocatalytic activity studied by UV-Visible spectrophotometric analysis and high performance liquid chromatography (HPLC) revealed the superior activity of the nanoparticles for decomposition of BPB. The decomposition rate of BPB under photooxidation mechanism is higher than of photocatalysis mechanism. Both mechanisms obey pseudo-second order kinetics and the decomposition was identified from the shifted spectra of treated solution. Furthermore, the electrochemical sensing activity for the detection of heavy metal Hg2+ showed an increasing of sensitivity and feasibility of the SnO2/Au electrode compared to the bare Au with the limit of detection of 0.001 970 ppm. This result reveals the facile green synthesis route of SnO2NPs with the promising activities.

Investigation of metalloporphyrin compound in maltenes of duri crude oil

Metalloporphyrin is one of the compounds that could potentially cause deactivation of catalysts in the process of catalytic cracking and hydrotreating. Knowledge of the structure of metalloporphyrin can be used as the basic information in overcoming the problem of catalyst poisoning. This work is performed to identify metalloporphyrins in the maltenes fraction of Duri crude oil. The low content of asphaltenes in Duri crude oil with a fractional weight of 0.79 %, allows a high level of metalloporphyrin in the fraction of maltenes which has a fractional weight of 82.73 %. Metalloporphyrin in the maltenes derivate fraction, saturates, aromatics, and resin were separated using column chromatography. Saturates, aromatics and resins have fractional weight of 49.75; 34.92; and 15.33 %, respectively. Only resin contained metalloporphyrin based on the analysis of UV-Vis spectrophotometer and Fourier-transform infrared spectroscopy (FT-IR), thus metalloporphyrins in resin was further separated into fractions by column chromatography. The result of UV-Vis spectrophotometer analysis for resin separation showed an absorbance peak of metalloporphyrin at 480–700 nm, while FT-IR analysis showed the presence of pyrrole group as porphyrin base framework with vibrational region at 400–1100 cm−1 The results of micro plasma-atomic emission spectrometer (MP-AES) analysis showed the presence of Fe, Ni, and V metals content. The liquid chromatography-mass spectrometer (LC-MS) analysis showed the molecular structure of the obtained compound was C33H34N4VO2. According to the results, metalloporphyrins presented in the maltenes fraction of Duri crude oil was vanadyl porphyrin.

Ultrasound-assisted biosynthesis of silver and gold nanoparticles using Clitoria ternatea flower

This research focused on biosynthesis of silver and gold nanoparticles using Clitoria ternatea flower extracts under the ultrasound-assisted method. The synthesized nanoparticles were detected by UV-Vis spectrophotometric analysis, x-ray diffraction, scanning electron microscope, and transmission electron microscope. The effect of ultrasound method on physicochemical properties of the nanoparticles was compared to the use of reflux method. The influence of the character on biological activity of the nanoparticles were tested for their antibacterial activity against Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, and Streptococcus pyogenes bacteria. Chemical activity of the nanoparticles was also evaluated as antioxidant by using radical inhibition by using 2,2-diphenyl-1-picrylhydrazyl radicals (DPPH) assay. The results showed that Clitoria ternatea flower exhibited reduction capability to form nanoparticles with the particle size ranging at 18-50 nm. In general, the ultrasound produces smaller particle size compared with reflux method for both silver and gold nanoparticles. The smaller particle size obtained from the ultrasound-assisted method compared to the Reflux method was found to give higher antibacterial activity toward tested bacteria. The nanoparticles demonstrated the antioxidative activity as shown by the DPPH inhibition at more than 50%. The results suggest that the use of Clitoria ternatea flower extracts as reducing agent and ultrasound-assisted synthesis are fit as a green method for the synthesis of silver and gold nanoparticles.

Biodegradation of Malathion Using Pseudomonas stutzeri(MTCC 2643)

Pesticides are applied in agricultural fields for controlling pest population to achieve crop protection. But they cause damage to nontarget organisms and affect the quality of environment including water, air and soil. The present study has been designed to test the efficiency of Pseudomonas stutzerion the degradation of malathion. The bacterial strain was subjected to 50, 100, 150 and 200 ppm of malathion in minimal broth for 30 hours and changes in orthophosphate levels, pH and turbidity were monitored for every six hours. Efficiency of free and immobilized cells were compared for orthophosphate release. Influence of different sugars on degradation was also compared. Degradation of 150 ppm of malathion was confirmed with UV-Visible spectrophotometric analysis and HPLC analysis. The data were subjected to two way analysis of variance and the results are discussed.