Expression patterns of cp4-epsps gene in diverse transgenic Saccharum officinarum L. genotypes.

Glyphosate, a functional analogue of phosphoenolpyruvate (PEP), blocks the shikimate pathway by inhibiting the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS; EC 2.5.1.19) through interference with the conversion of (shikimate-3-phosphate) S3P and PEP to 5-enolpyruvylshikimate-3-phosphate (EPSP) and subsequently leads to plant death. This metabolic pathway possesses great potential to be used for development of herbicide resistant transgenic crops and here in this study, we wanted to check the expression potential of CP4-EPSPS gene in various sugarcane genotypes. A synthetic version of CP4-EPSPS gene synthesized commercially, cloned in pGreen0029 vector, was transformed into regenerable embryogenic calli of three different sugarcane cultivars HSF-240, S2003US-778 and S2003US-114 using biolistic gene transfer approach for comparative transcriptional studies. Transgenic lines screened by PCR analysis were subjected to Southern hybridization for checking transgene integration patterns. All the tested lines were found to contain multiple (3-6) insert copies. Putative transgenic plants produced the CP4-EPSPS protein which was detected using immunoblot analysis. The CP4-EPSPS transcript expression detected by qRT-PCR was found to vary from genotype to genotype and is being reported first time. In vitro glyphosate assay showed that transformed plants were conferring herbicide tolerance. It is concluded that different cultivars of sugarcane give variable expression of the same transgene and reasons for this phenomenon needs to be investigated.

Enhanced degradation of hydrocarbons by gamma ray induced mutant strain of Pseudomonas putida.

Soil contamination due to petroleum hydrocarbons is a ubiquitous environmental problem for which efficient remediation alternatives are required. Application of hydrocarbons degrading bacteria with enhanced degradation potential is such an alternative. The aim of present investigation was to induce mutagenicity in Pseudomonas putida through gamma-ray irradiation for the enhanced degradation of crude oil. A total of mutant 10 bacterial strains (300A-J) were screened for their degradation abilities in vitro; among which the performance of 300-B was outstanding. Subsequently, spiked soil (30 g/kg crude oil) was augmented with the wild-type parent strain and mutant 300-B strain in individual experiments. Bacterial inoculation in both experiments enhanced hydrocarbons degradation; however, degradation was 46.3% higher when 300-B mutant strain was employed. This improved oil degradation was found to have a strong positive correlation with the gene abundance and expression of the mutant strain, suggesting its successful survival and catabolic potential in situ. Concomitantly, a better nutrients assimilation and water utilization was observed in the experiment containing 300-B mutant. Yet preliminary, these findings highlight the importance of gamma ray irradiation towards improved degradation potential of previously isolated hydrocarbons degrading bacteria.

An ultra low-cost smartphone device for in-situ monitoring of acute organophosphorus poisoning for agricultural workers.

In this work, we present an ultra-low-cost smartphone device for in situ quantification of OP poisoning severity. The performance of the lens-less smartphone spectrum apparatus (LeSSA) is evaluated using standard human Interleukin-6 (IL-6) immunoassay kits. Upon dose-response curve fitting, LeSSA demonstrates an accuracy of 99.5%. The limit of detection (LOD) of LeSSA was evaluated through comparison of 6.4 pg/ml with standard laboratory grade UV-vis spectrophotometer at 5.5 pg/ml. Evaluating the capacity of LeSSA in spike solution by combining plasma cholinesterase (PChE) and human plasma shows consistency at agreement of 97.6% between LeSSA and the laboratory instrument. For application demonstration, the activity of PChE for 24 agricultural workers' plasma samples was measured with LeSSA, showing exceptional agreement (r2 = 0.92) with the laboratory instrument reference. In addition to near laboratory grade accuracy, the total manufacturing cost of LeSSA is only $20 USD highlighting it's affordability. With LeSSA, clinicians can evaluate OP poisoning severity without the need to transport patient samples to facilities at far distances. Utilizing LeSSA, immediate results can be used for administration of appropriate treatment.

Polyhexamethylene biguanide functionalized cationic silver nanoparticles for enhanced antimicrobial activity.

Polyhexamethylene biguanide (PHMB), a broad spectrum disinfectant against many pathogens, was used as a stabilizing ligand for the synthesis of fairly uniform silver nanoparticles. The particles formed were characterized using UV-visible spectroscopy, FTIR, dynamic light scattering, electrophoretic mobility, and TEM to measure their morphology and surface chemistry. PHMB-functionalized silver nanoparticles were then evaluated for their antimicrobial activity against a gram-negative bacterial strain, Escherichia coli. These silver nanoparticles were found to have about 100 times higher bacteriostatic and bactericidal activities, compared to the previous reports, due to the combined antibacterial effect of silver nanoparticles and PHMB. In addition to other applications, PHMB-functionalized silver nanoparticles would be extremely useful in textile industry due to the strong interaction of PHMB with cellulose fabrics.

Antioxidant and antimicrobial attributes and phenolics of different solvent extracts from leaves, flowers and bark of Gold Mohar [Delonix regia (Bojer ex Hook.) Raf].

This paper describes the antioxidant and antimicrobial activities and phenolic components of different solvent (absolute methanol, absolute ethanol, absolute acetone, 80% methanol, 80% ethanol, 80% acetone and deionized water) extracts of leaves, flowers and bark of Gold Mohar [Delonix regia (Bojer ex Hook.) Raf.]. The extract yields from leaves, flowers and bark ranged from 10.19 to 36.24, 12.97 to 48.47 and 4.22 to 8.48 g/100 g dry weight (DW), respectively. Overall, 80% methanol extract produced from the leaves exhibited significantly (P < 0.05) higher antioxidant activity, with high phenolic contents (3.63 g GAE/100 g DW), total flavonoid contents (1.19 g CE/100 g DW), inhibition of peroxidation (85.54%), DPPH scavenging capacity (IC(50) value 8.89 µg/mL) and reducing power (1.87). Similarly, this 80% methanol leaves extract also showed superior antimicrobial activity. HPLC analysis of the 80% methanol extracts for individual phenolics revealed the presence of gallic, protocatechuic and salicylic acid in leaves; gallic, protocatechuic, salicylic, trans-cinnamic and chlorogenic acid in flowers, and gallic acid in bark as the main (amount > 1.50 mg/100 g DW) phenolic acids. Besides, small amounts ( < 1.50 mg/100 g DW) of some other phenolic acids such as sorbic, sinapic, p-coumaric, m-coumaric, ferulic, caffeic, 3-hydroxybenzoic, 4-hydroxycinnamic and 4-hydroxybenzoic acids were also detected. The extracts of the tested parts of Gold Mohar, especially, the leaves, might be valuable for functional food and therapeutic applications.

In situ growth of gold nanoparticles on latent fingerprints-from forensic applications to inkjet printed nanoparticle patterns.

Latent fingerprints are made visible in a single step by in situ growth of gold nanoparticles on ridge patterns. The chemicals, among the essential components of human sweat, found responsible for the formation and assembly of gold nanoparticles are screened and used as ink to write invisible patterns, using common ball pen and inkjet printer, which are then developed by selectively growing gold nanoparticles by soaking them in gold salt solution.

Synthesis and use of self-assembled rhamnolipid microtubules as templates for gold nanoparticles assembly to form gold microstructures.

Natural unmodified rhamnolipids are thermally self-assembled into soft microtubules, which can produce gold nanoparticles onto themselves due to the presence of rhamnose sugar moieties at their surface. The loading of gold nanoparticles on composite microtubules can be controlled by varying the concentration of gold salt to rhamnolipid and the reaction temperature. The composite rhamnolipid-gold nanoparticle microtubules are then heat treated to produce porous gold microwire-like structures with fairly controlled nanostructured features, which may have interesting applications in catalysis, biosensing and electronics.

Surface properties and sub-surface aggregate assimilation of rhamnolipid surfactants in different aqueous systems.

Tensioactive properties of rhamnolipids produced by a Pseudomonas aeruginosa strain were investigated in the presence or absence of Sr(2+) or Pb(2+). Surface and interfacial properties, and aggregate forming properties and morphologies were studied by various techniques including scanning electron microscopy. When the pH of a rhamnolipid aqueous solution (40 mg/l) was increased from 5 to 8, irregular vesicles gradually took the shape of oligo-vesicles, then regular vesicles and finally smaller spherical vesicles. Addition of metal ions controlled the aggregates' morphology and stability, and influenced the surface and interfacial behavior of rhamnolipid solutions.

Biodegradation of chlorpyrifos and its hydrolysis product 3,5,6-trichloro-2-pyridinol by Bacillus pumilus strain C2A1.

A bacterial strain C2A1 isolated from soil was found highly effective in degrading chlorpyrifos and its first hydrolysis metabolite 3,5,6-trichloro-2-pyridinol (TCP). On the basis of morphology, physiological characteristics, biochemical tests and 16S rRNA sequence analysis, strain C2A1 was identified as Bacillus pumilus. Role of strain C2A1 in the degradation of chlorpyrifos was examined under different culture conditions like pH, inoculum density, presence of added carbon/nutrient sources and pesticide concentration. Chlorpyrifos was utilized by strain C2A1 as the sole source of carbon and energy as well as it was co-metabolized in the presence of glucose, yeast extract and nutrient broth. Maximum pesticide degradation was observed at high pH (8.5) and high inoculum density when chlorpyrifos was used as the sole source and energy. In the presence of other nutrients, chlorpyrifos degradation was enhanced probably due to high growth on easily metabolizable compounds which in turn increased degradation. The strain C2A1 showed 90% degradation of TCP (300 mg L(-1)) within 8 days of incubation.

DNA damage in Pakistani agricultural workers exposed to mixture of pesticides.

A cross-sectional study was designed to determine whether occupational exposure to a complex mixture of pesticides results in a significant increase of DNA damage in farmers chronically exposed to pesticides in open fields. Leukocytes from 47 agriculture workers exposed to pesticides and 50 controls were evaluated with comet assay. Workers recruitment was based on their exposure to pesticides during the spraying season on cotton crop. Serum from these individuals was also analyzed for pesticides presence using high performance liquid chromatography. Statistically significant difference (P < 0.001) in DNA damage of exposed individuals (mean +/- S.D 14.80 +/- 3.04 microm) was observed when compared with control group (6.54 +/- 1.73 microm) as studied on the basis of comet tail length. Smokers had significantly higher mean comet tail length than nonsmokers and ex-smokers in both workers (20.26 +/- 3.53 vs. 14.19 +/- 4.25, P < 0.001) and controls (7.86 +/- 1.09 vs. 5.80 +/- 1.59, P < 0.001), whereas age had a minimal effect on DNA damage (P < 0.05). The length of pesticide exposure is positively associated with DNA damage in exposed individuals (P < 0.001). Our study shows that chronic exposure to pesticides produces DNA damage in pesticide sprayers and suggests that this type of monitoring is recommended in preventive policies for pesticide sprayers.

Characterization of rhamnolipids produced by a Pseudomonas aeruginosa mutant strain grown on waste oils.

Pseudomonas aeruginosa EBN-8 mutant rhamnolipids produced on waste oils were investigated using normal-phase thin layer chromatography and fast atom bombardment mass spectrometry. Negative ion mode mass spectra yielded [M - H](-) ions and their fragment ions, which gave some indications on the sequence of rhamnolipid biosynthesis. Five rhamnolipid homologs [viz. RC(10)C(10) (m/z 503), RC(12)C(10) or RC(10)C(12) (531), RRC(10)C(8) or RRC(8)C(10) (621), RRC(10)C(10) (649) and RRC(12)C(10) or RRC(10)C(12) (677)] were detected in four rhamnolipid combinations under the different carbon sources. The prevalence of rhamnolipids was confirmed by Fourier transform infrared and one-dimensional proton nuclear magnetic resonance. We also observed some correlations between the tensioactive characteristics and structural chemistry of the rhamnolipid surfactants.

Paper and board mill effluent treatment with the combined biological-coagulation-filtration pilot scale reactor.

Pilot scale reactor based on combined biological-coagulation-filtration treatments was designed and evaluated for the treatment of effluent from a paper and board mill. Biological treatment by fed batch reactor (FBR) followed by coagulation and sand filtration (SF) resulted in a total COD and BOD reduction of 93% and 96.5%, respectively. A significant reduction in both COD (90%) and BOD (92%) was also observed by sequencing batch reactor (SBR) process followed by coagulation and filtration. Untreated effluent was found to be toxic, whereas the treated effluents by either of the above two processes were found to be non-toxic when exposed to the fish for 72h. The resultant effluent from FBR-coagulation-sand filtration system meets National Environmental Quality Standards (NEQS) of Pakistan and can be discharged into the environment without any risks.

Kinetics of p-nitrophenol degradation by Pseudomonas pseudomallei wild and mutant strains.

Pseudomonas pseudomallei EBN-10 strain, previously isolated from a local pharmaceutical industry's wastewater, was spontaneously adapted to higher p-nitrophenol (PNP) levels, which then was subjected to gamma ray-induced mutagenesis; the efficient isolates hence obtained were designated as EBN-11 and EBN-12, respectively. EBN-12 mutant strain could completely mineralize PNP (100 mg/L) on the minimal media in 24 h while, the parent strain utilized only 6% of it. Addition of glucose as co-substrate further increased the PNP degradation rate; however, phenol inclusion inhibited the degradation process. Ammonium sulphate was experienced as the best of the nitrogen sources used by EBN-12 mutant strain, while degrading PNP.

Characteristics of phenol biodegradation in saline solutions by monocultures of Pseudomonas aeruginosa and Pseudomonas pseudomallei.

Phenol is a highly toxic and carcinogenic compound and its biodegradation is very important to meet the environmental regulations. Two bacterial strains capable of utilizing phenol as a sole source of carbon were isolated from the wastewater of a pharmaceutical industry. On the basis of morphological and biochemical characteristics these strains were identified as Pseudomonas aeruginosa and Pseudomonas pseudomallei. Both of these strains were very efficient for phenol degradation. P. pseudomallei degraded phenol at a maximum concentration of 1500 mg L(-1) within seven days with a specific growth rate of 0.013 h(-1) and phenol degradation rate of 13.85 mg L(-1)h(-1). Maximum initial concentration of phenol utilized by P. aeruginosa was 2600 mg L(-1) with 0.016 h(-1) specific growth rate and 26.16 mg L(-1)h(-1) phenol degradation rate. Moreover, the effect of various salts i.e., NaCl, KCl, Na(2)SO(4) and K(2)SO(4) on the growth of these strains and phenol degradation rate (at 1000 mg L(-1)) was studied. In the presence of these salts, P. aeruginosa showed up to 1.53 and 1.34 times faster phenol degradation rate and specific growth rate, respectively as compared to P. pseudomallei. In addition, P. aeruginosa exhibited higher chemical oxygen demand (COD) and biochemical oxygen demand (BOD) reduction rates as compared to the strain P. pseudomallei.

Improved production of biosurfactant by a Pseudomonas aeruginosa mutant using vegetable oil refinery wastes.

Biosurfactant production by Pseudomonas aeruginosa EBN-8 mutant was studied in shake flasks on separate wastes from canola, soybean and corn oil refineries. Of the substrates tested, canola oil refinery waste (COD=20 g l(-1)) supplemented with sodium nitrate (at COD/N=20) showed the best microbial growth (4.50 g l(-1)) and rhamnolipid production (8.50 g l(-1)), at 10 d of incubation with the specific growth rate of 0.316 h(-1) and specific product yield of 0.597 g g(-1) h. Its cell-free supernatant showed the critical micelle dilution (CMD) of 150 and surface tension (ST) of 28.5 mN m(-1).

Physicochemical and surface-active properties of biosurfactant produced using molasses by a Pseudomonas aeruginosa mutant.

Production of a microbial surfactant was studied by growing Pseudomonas aeruginosa EBN-8 mutant on varying concentrations (on the basis of total sugars) of clarified blackstrap molasses as a sole carbon and energy source with or without auxiliary synthetic nitrogen source in 250 mL shake flasks. The progress of fermentation process was monitored by measuring the production of metabolites, and surface-active and emulsification properties of the cell-free culture broth. The biosurfactant was isolated from the supernatant by acid precipitation followed by solvent extraction. The amount of rhamnolipids produced was determined by the orcinol method. The highest dry cell biomass (1.67 g/L) and rhamnolipid (1.45 g/L) yields were observed, at 96 h of incubation on 2% total sugars-based molasses amended with sodium nitrate (at C:N, 20:1) with the product yield related to dry cell biomass (YP/X, g/g) of 0.869, specific product formation rate (V, h(-1)) of 0.295 and volumetric productivity rate (PV, g/L/h) of 0.015. The surface tension of this culture medium dropped to 28.0 from 50.0 mN/m.

Production kinetics and tensioactive characteristics of biosurfactant from a Pseudomonas aeruginosa mutant grown on waste frying oils.

Various waste frying oils (WFOs) were evaluated as substrates for rhamnolipid production by Pseudomonas aeruginosa mutant EBN-8 in the presence or absence of rhamnolipid precursor, under single-/batch-fed conditions. Soybean WFO was the best substrate, producing 9.3 g rhamnolipid l(-1) with the specific product yield of 2.7 g g(-1) h, under batch-fed cultivation with the addition of rhamnolipid precursor. The surface tension of the cell-free culture broth (CFCB) was 29.1 mN m(-1 )and the interfacial tension against n-hexadecane was <1 mN m(-1). The hydrocarbon/ CFCB systems showed the relative emulsion stability to be in the range of 89.7-92.3.

Production of biosurfactant using different hydrocarbons by Pseudomonas aeruginosa EBN-8 mutant.

The present investigation dealt with the use of previously isolated and studied gamma-ray mutant strain Pseudomonas aeruginosa EBN-8 for the production of biosurfactant by using different hydrocarbon substrates viz. n-hexadecane, paraffin oil and kerosene oil, provided in minimal medium, as the sole carbon and energy sources. The batch experiments were conducted in 250 mL Erlenmeyer flasks, containing 50 mL minimal salt media supplemented with 1% (w/v) hydrocarbon substrate, inoculated by EBN-8 and incubated at 37 degrees C and 100 rpm in an orbital shaker. The sampling was done on 24 h basis for 10 d. The surface tension of cell-free culture broth decreased from 53 to 29 mN/m after 3 and 4 d of incubation when the carbon sources were paraffin oil and n-hexadecane, respectively. The largest reduction in interfacial tension from 26 to 0.4 mN/m was observed with n-hexadecane, while critical micelle dilution was obtained as 50 x CMC for paraffin oil as carbon source. When grown on n-hexadecane and paraffin oil, the EBN-8 mutant strain gave 4.1 and 6.3 g of the rhamnolipids/L, respectively. These surface-active substances subsequently allowed the hydrocarbon substrates to disperse readily as emulsion in aqueous phase.

The concentrations of hexadecane and inorganic nutrients modulate the production of extracellular membrane-bound vesicles, soluble protein, and bioemulsifier by Acinetobacter venetianus RAG-1 and Acinetobacter sp. strain HO1-N.

In the present study, we addressed the possibility that the production of both bioemulsifiers and membrane-bound vesicles may be a common feature of the growth of Acinetobacter spp. on alkanes, and we determined the extent to which the release of extracellular products by these organisms is regulated by the concentrations of the alkane substrate and inorganic nutrients. To accomplish this objective, we grew Acinetobacter venetianus RAG-1 and Acinetobacter sp. strain HO1-N with different concentrations of nutrients and assayed for extracellular products. The results indicated that the release of vesicles, soluble protein, and bioemulsifier was promoted in various degrees by higher concentrations of hexadecane and inorganic nutrients, while the specific activities of the bioemulsifiers were enhanced with lower nutrient concentrations. Based on our findings, we propose that under conditions of nutrient excess, these strains produce membrane-bound vesicles to function in "luxury uptake" of the alkane substrate for delivery and storage in the form of inclusions. Under the same conditions, soluble bioemulsifier and protein may perform auxiliary roles in cell desorption and (or) alkane uptake. With low concentrations of nutrients, the decreased production of vesicles, protein, and bioemulsifier and the increased activity of the emulsifier may represent a mechanism for reducing biosynthetic demands and conserving cellular material.