Lycopene attenuates silver nanoparticle-induced liver injury in albino mice.

Lycopene is a carotenoid widely used for its dominant antioxidant properties and beneficial health effects. Silver nanoparticles (AgNP) have gained attention for use in many medicinal and consumer products, leading to animal, human, and environmental exposure. This study investigated the dose-dependent effects of lycopene on AgNP-induced hepatotoxicity in albino mice. The four experimental groups, comprising eight albino mice each, were as follows: Group I, vehicle control (C); Group II, AgNP-treated (5 mg/kg/day) (AgNP); Group III, AgNP/lycopene-treated (5 + 10 mg/kg/day) (AgNP + LP10); and Group IV, AgNP/lycopene-treated (5 + 100 mg/kg/day) (AgNP + LP100). All solutions were orally administered to the mice once in a day for consecutive 14 days. The levels of serum aspartate transaminase, alanine transaminase, alkaline phosphatase, and total bilirubin were significantly higher in the AgNP-treated group than in the control group but significantly lower in the AgNP + LP100 group than in the AgNP-treated group. A significant decrease in reduced glutathione level and superoxide dismutase activity and an increase in lipid peroxidation were observed in the AgNP-treated group; these were significantly suppressed in the AgNP+LP100 as compared to AgNP-treated group. Histopathological examination showed substantial morphological alterations in hepatic tissues in the AgNP, which were adequately improved in the low and high dose lycopene-treated groups. The dose of 100 mg/kg/day of lycopene was more effective than 10 mg/kg/day, as pretreatment with high dose lycopene significantly diminished the adverse changes occurred due to AgNP in liver weight, hepatic architecture, serum functional markers, and antioxidant markers. Thus, present study shows that pretreatment with lycopene offers protection against AgNP-induced hepatotoxicity and oxidative stress.

Synergistic and antibiofilm potential of Curcuma aromatica derived silver nanoparticles in combination with antibiotics against multidrug-resistant pathogens.

Hospital acquired infections caused due to ESKAPE pathogens pose a challenge for treatment due to their growing antimicrobial resistance. Curcuma aromatica (CA) is traditionally known for its antibacterial, wound healing and anti-inflammatory properties. The present study highlights the biogenic synthesis of silver nanoparticles (CAAgNPs) capped and stabilized by the compounds from CA rhizome extract, also further demonstrating their antibacterial, antibiofilm and synergistic effects against multidrug-resistant (MDR) pathogens. CAAgNPs were synthesized using aqueous rhizome extract of CA (5 mg/ml) and AgNO3 (0.8 mM) incubated at 60°C up to 144 h. UV-vis spectroscopy, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) revealed CAAgNPs with characteristic peak at 430 nm, 13 ± 5 nm size of spherical shape, showing presence of silver and crystalline nature, respectively. Dynamic light scattering (DLS) and zeta potential confirmed their monodispersed nature with average diameter of 77.88 ± 48.60 nm and stability. Fourier transform infrared spectroscopic (FTIR) analysis demonstrated the presence of phenolic -OH and carbonyl groups possibly involved in the reduction and stabilization of CAAgNPs. The minimum inhibitory concentrations (MICs), minimum bactericidal concentrations (MBCs) and minimum biofilm inhibitory concentrations (MBICs) of CAAgNPs against Pseudomonas aeruginosa, NCIM 5029 and PAW1, and, Staphylococcus aureus, NCIM 5021 and S8 were in range from 8 to 128 µg/ml. Almost 50% disruption of pre-formed biofilms at concentrations 8-1,024 µg/ml was observed. Fluorescence microscopy and FESEM analysis confirmed cell death and disruption of pre-formed biofilms of P. aeruginosa PAW1 and S. aureus S8. Checkerboard assay demonstrated the synergistic effect of CAAgNPs (0.125-4 µg/ml) in combination with various antibiotics (0.063-1,024 µg/ml) against planktonic and biofilm forms of P. aeruginosa PAW1. The study confirms the antibacterial and antibiofilm activity of CAAgNPs alone and in combination with antibiotics against MDR pathogens, thus, reducing the dose as well as toxicity of both. CAAgNPs have the potential to be used in wound dressings and ointments, and to improve the performances of medical devices and surgical implants. In vivo toxicity of CAAgNPs however needs to be tested further using mice models.

Biodegradation of tributyl phosphate by novel bacteria isolated from enrichment cultures.

Tributyl phosphate (TBP) is an organophosphorous compound, used extensively (3000-5000 tonnes/annum) as a solvent for nuclear fuel processing and as a base stock in the formulation of fire-resistant aircraft hydraulic fluids and other applications. Because of its wide applications and relative stability in the natural environment TBP poses the problem of pollution and health hazards. In the present study, fifteen potent bacterial strains capable of using tributyl phosphate (TBP) as sole carbon and phosphorus source were isolated from enrichment cultures. These isolates were identified on the basis of biochemical and morphological characteristics and 16S rRNA gene sequence analysis. Phylogenetic analysis of 16S rRNA gene sequences revealed that two isolates belonged to class Bacilli and thirteen to ß and γ-Proteobacteria. All these isolates were found to be members of genera Alcaligenes, Providencia, Delftia, Ralstonia, and Bacillus. These isolates were able to tolerate and degrade up to 5 mM TBP, the highest concentration reported to date. The GC-MS method was developed to monitor TBP degradation. Two strains, Providencia sp. BGW4 and Delftia sp. BGW1 showed respectively, 61.0 ± 2.8% and 57.0 ± 2.0% TBP degradation within 4 days. The degradation rate constants, calculated by first order kinetic model were between 0.0024 and 0.0099 h(-1). These bacterial strains are novel for TBP degradation and could be used as an important bioresource for efficient decontamination of TBP polluted waste streams.

Development and application of a method for analysis of lufenuron in wheat flour by gas chromatography-mass spectrometry and confirmation of bio-efficacy against Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae).

A new analytical method using gas chromatography with mass spectrometry (GC-MS) for the quantitative determination of lufenuron, a benzoylphenylurea (BPU) class of insecticide, from wheat flour has been developed and applied for time-dependent residue monitoring in treated wheat flour. The analyte was extracted from wheat flour by a single step solid-liquid extraction by using ethyl acetate and subsequently cleaned up using the Primary Secondary Amine as a sorbent prior to GC-MS analysis. The present method provides sufficient sensitivity as reflected by the values of limit of detection (LOD) and limit of quantification (LOQ), 5 ng/mL (S/N approximately 3) and 50 ng/mL (the lowest validation point on the calibration curve), respectively. The calibration curve showed an excellent linearity in the concentration range of 50-1000 ng/mL (r2=0.998). The average recovery for spiked samples at three concentrations (150, 300, and 450 ng/g) was 98.23+/-2.52% R.S.D. The method was applied for the determination of lufenuron residues in treated wheat flour samples. Simultaneous determination of bio-efficacy of lufenuron residues was also carried out against the red flour beetle, Tribolium castaneum to correlate the actual residual effect of lufenuron as detected by the analytical method, over a period of 3 months. The findings revealed that the residual concentration of lufenuron were neither uniform nor in descending order over a period of 3 months in wheat flour, possibly because of an uneven dispersal in the treated wheat which was subsequently milled into flour, as confirmed by GC-MS analysis. However, the residues of lufenuron were sufficient to produce 100% mortality of T. castaneum larvae up to 3 months. The results have been discussed in view of the potential of lufenuron as a candidate molecule for the control of stored product pests.