Escherichia Coli Fed Paper-Based Microfluidic Microbial Fuel Cell With MWCNT Composed Bucky Paper Bioelectrodes.

This paper demonstrates a simple-in-struct- ure, cost-effective, and environment-friendly Microfluidic Paper-based Analytical Device for Microbial Biofuel Cell ( µ PAD-MBFC). It consists of a microchannel with biofuel cell (Escherichia.Coli) and an oxidant (aerated tap water) flowing co-parallelly over Multiwalled Carbon Nanotube (MWCNT)-based Bucky Paper (BP) electrodes using a self-capillary and co-laminar flow mechanism. The electrochemical studies, such as open circuit potential (OCP) and polarization were evaluated using a potentiostat. Various volumetric bacterial studies were also carried out to find out the best suitable optimal bacterial volume. Subsequently, the morphological and detailed element composition study of electrode surface was performed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. This well-designed portable µ PAD-MBFC yields a maximum power density of 4 [Formula: see text]/cm2 ( [Formula: see text]/cm2) at 0.405 V over [Formula: see text] of culture and leveraging to its long-lasting potential to operate miniaturized microelectronics sensors and portable devices.

Attenuation of quorum-sensing-dependent virulence factors and biofilm formation by medicinal plants against antibiotic resistant Pseudomonas aeruginosa.

Pseudomonas aeruginosa use small signaling molecules such as acyl homoserine lactones (AHLs), which play an important role in release virulence factors and toxin for further establishment of host infection. Thus, involving with the QS system would provide alternative ways of preventing the pathogenicity. In the present study, totally six medicinal plants (Terminalia bellerica, Celastrus paniculatus, Kingiodendron pinnatum, Schleichera oleosa, Melastoma malabathricum, Garcinia gummi-gutta) were screened for anti-QS activity using biomonitor strain of Chromobacterium violaceum CV12472. The primary screening of antimicrobial activity of all the plant extracts have inhibited the growth of tested bacterial species. Of these at the sub-minimum inhibitory concentration the methanol extract of T. bellerica (0.0625-0.5 mg/ml) has significantly inhibited violacein production (20.07-66.22%) in C. violaceum (CV12472). Consequently, the extract of T. bellerica has reduced the production of pyocyanin, exopolysaccharide and biofilm formation in P. aeruginosa strains. Fluorescence and scanning electron microscopy analysis confirmed the reduction of biofilm formation in P. aeruginosa strains when treated with T. bellerica. GC-MS analysis showed the active compounds inhibited the production of virulence factors of P. aeruginosa. The results suggest the possible use of this T. bellerica as an anti-QS and anti-biofilm agent to control Pseudomonas infection. Interference of QS provides an important means for the inhibition of bacterial virulence and thus aids in treatment strategies.

Recovery of methane-rich gas from solid-feed anaerobic digestion of ipomoea (Ipomoea carnea).

Studies are presented on new types of anaerobic digesters in which chopped or dry crushed Ipomoea carnea was fed without any other pretreatment, in an attempt to develop commercially viable means of utilizing the otherwise very harmful plant. Two types of solid-feed anaerobic digesters (SFADs) were studied. The first type had a single vessel in which the bottom 35% portion was separated from the top portion by a perforated PVC disk. The weed was charged from the top and inoculated with anaerobically digested cowdung-water slurry. The fermentation of the weed in the reactor led to the formation of volatile fatty acids (VFAs) plus some biogas. The leachate, rich in the VFAs, was passed through the perforated PVC sheet and collected in the lower portion of the vessel. The other type of reactors had two vessels, the first one was fully charged with the weed and the second received the VFA leachate. With both types were attached upflow anaerobic filters (UAFs) which converted the leachate into combustible biogas consisting of approximately 70% methane. All SFADs developed very consistent performance in terms of biogas yield within 17 weeks of start. The two-compartment reactors yielded significantly more biogas than the single-compartment reactors of corresponding total volume, and the reactors with which anaerobic filters (AF) were attached yielded more biogas than the ones without AF. The best performing units generated 2.41m(3) of biogas per m(3) of digester volume, as compared to 0.1-0.2m(3) of biogas, m(-3)d(-1), obtainable with conventional digesters. This indicates the viability of this technology. The spent weed can be vermicomposted directly to obtain good soil-conditioner cum fertilizer; earthworm Eudrilus eugeniae produced 540mg vermicast per animal every day, achieving near total conversion of feed to vermicast in 20 days. The proposed systems, thus, makes it possible to accomplish total utilization of ipomoea.