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This research work aims to synthesize environmentally benign and cost-effective metal nanoparticles. In this current research scenario, the leaf extract of Cedrela toona was used as a reducing agent to biosynthesize silver nanoparticles (AgNPs). The synthesis of AgNPs was confirmed by the color shift of the reaction mixture, i.e., silver nitrate and plant extract, from yellow to dark brown colloidal suspension and was established by UV-visible analysis showing a surface plasmon resonance band at 434 nm. Different experimental factors were optimized for the formation and stability of AgNPs, and the optimum conditions were found to be 1 mM AgNO3 concentration, a 1:9 ratio of extract/precursor, and an incubation temperature of 70°C for 4 h. The Fourier transform infrared spectroscopy spectra indicated the presence of phytochemicals in the leaf extract that played the role of bioreducing agents in forming AgNPs. X-ray diffraction patterns confirmed the presence of AgNPs with a mean size of 25.9 nm. The size distribution and morphology of AgNPs were investigated by scanning electron microscopy, which clearly highlighted spherical nanoparticles with a size distribution of 22–30 nm with a mean average size of 25.5 nm. Moreover, prominent antibacterial activity was found against Enterococcus faecalis (21 ± 0.5 mm), Bacillus subtilis (20 ± 0.9 mm), Pseudomonas aeruginosa (18 ± 0.3 mm), Staphylococcus aureus (16 ± 0.7 mm), Klebsiella pneumoniae (16 ± 0.3 mm), and Escherichia coli (14 ± 0.7 mm). In addition, antioxidant activity was determined by DPPH and ABTS assays. Higher antioxidant activity was reported in AgNPs compared to the plant extract in both DPPH (IC50 = 69.62 µg·ml−1) and ABTS assays (IC50 = 47.90 µg·ml−1). Furthermore, cytotoxic activity was also investigated by the MTT assay against MCF-7 cells, and IC50 was found to be 32.55 ± 0.05 µg·ml−1. The crux of this research is that AgNPs synthesized from the Cedrela toona leaf extract could be employed as antibacterial, antioxidant, and anticancer agents for the treatment of bacterial, free radical-oriented, and cancerous diseases.

Antibiotic resistance is a world wide problem mainly in developing countries. In this work, coelomic fluid (PCF) and paste (PBP) of Pheretima posthuma was assessed for its potential as antibiofilm and anti-quorum sensing (QS) agent against pathogenic bacterial biofilms. PCF and PBP were extracted and biofilm formation time kinetics was examined using crystal violet staining method by utilizing four bacterial isolates in bispecies biofilm (06 combinations; MH5-MH10) and multi species biofilms (05 combinations; MH11-MH15). QS study was performed by determining pyocyanin formation time kinetics using 03 P. aeruginosa strains at various time periods (0, 24, 48, 72, 96 and 120 hours). Following next, anti-QS effect was analyzed by measuring pyocyanin concentrations. Results showed that among bispecies bacterial biofilms, MH5-MH7 combinations showed significantly higher biofilm (p < 0.05) after 72 hours while other three (MH8-MH10) produced maximum biofilm after 48 to 72 hours. Likewise, for multispecies biofilms, maximum biofilm was noted after 48-72 hours. QS analysis revealed that PA1 strain synthesized highly significant (p < 0.001) pyocyanin (20 µg/mL) after 96 hours compared to PA2 and PA3 strains, which formed significant pyocyanin (18 µg/mL) after 72 hours. Also, 100-150 µg/mL of both PCF and PBP exhibited a significant (p < 0.05) reduction in biofilm while 200 µg/mL concentration showed highest QS against all selected strains. To our knowledge, this is the first assessment of its kind on the potential application of earthworm PCF and PBP for its antibiofilm and anti-QS potential. The study recommends precise chemistry of bioactive agents and their probable mechanism(s) of actions for the observed interference. Also, new pharmaceutical drugs synthesized using bioactive agents from PCF and PCB may surely have the potential to manage different infection problems caused by bacterial biofilms. [ABSTRACT FROM AUTHOR]

The aim of the present research was the efficient degradation of industrial textile wastewater dyes using a very active cloned laccase enzyme. For this purpose, potent laccase-producing bacteria were isolated from soil samples collected from wastewater-replenished textile sites in Punjab, Pakistan. The laccase gene from locally isolated strain LI-81, identified as Bacillus megaterium, was cloned into vector pET21a, which was further transformed into E. coli BL21 codon plus. The optimized conditions for the increased production of laccase include fermentation in a 2% glucose, 5% yeast extract and 250 mg/L CuSO4 medium with pH 7.5; inoculation with 5% inoculum; induction with 0.1 mM IPTG at 0.5 O.D.; and incubation for 36 h at 37 °C. The crude enzyme produced was employed for the removal of commercially used textile dyes. The dyes were quickly precipitated under optimized reaction conditions. Rose bengal, brilliant green, brilliant blue G, Coomassie brilliant blue R and methylene blue were precipitated at rates of 10.69, 54.47, 84.04, 78.99 and 7.40%, respectively. The FTIR and UV–Vis spectroscopic analyses of dyes before and after confirmed the chemical changes brought about by the cloned laccase that led to the dye removal. [ABSTRACT FROM AUTHOR]

Present study was conducted to determine the efficacy of novel thermostable protease in poultry production. The protease was produced from Geobacillus sp. SBS-4S using Luria Bertani medium and it was used as supplement in poultry feed trial. The data were statistically analyzed by Multivariate Analysis of Variance. For feeding, 150 day-old broiler chicks were divided randomly into 5 groups having 30 chicks each. Group A served as negative control, group B, C and D as experimental groups which were supplemented in the basal diet with 2500, 5000 and 7500 IU/kg of locally characterized thermostable protease while group E was supplemented with the commercially available neutral protease (5000 IU/ kg) that served as a positive control. The trial lasted for five weeks and during the trial period birds were offered ad libitum access to water and feed. The maximal weight gain was recorded when the feed was supplemented with 7500 IU/Kg of locally characterized protease. The evaluation of data of various groups obtained after 3rd, 4th and 5th weeks of trial demonstrated significant change (P≤ 0.05) in weight gain, feed up take and feed conversion ratio (FCR) as compared to negative control. Locally produced protease showed promising results as compared to positive control which is being used currently in the poultry industry. The weight gain, feed intake and feed conversion ratio of 1891.54g, 3750g and 1.98 of experimental group D were comparable to 1874.49g, 3740 g and 1.995 in case of positive control. The ability of protease to enhance weight gain, feed consumption and FCR in poultry birds makes it a strong candidate for the replacement of imported counterpart being utilized currently in poultry feed industry. [ABSTRACT FROM AUTHOR]