14 research outputs found
Application of the Polar Organic Chemical Integrative Sampler for Isolation of Environmental Micropollutants â A Review
In vitro propagation of Rhododendron tomentosum - an endangered essential oil bearing plant from peatland
Rhododendron tomentosum Harmaja (formerly Ledum palustre L.) is a medicinal peat bog plant native to northern
Europe, Asia and North America. This plant has a distinctive aroma thanks to the presence of essential oil, to
which it also owes its anti-inflammatory, analgesic, antimicrobial and insecticidal properties. However, in Europe
R. tomentosum is classified as an endangered species, mainly due to degradation of peatlands. In the present
work, the micropropagation protocol for R. tomentosum was established for the first time, providing both an ex
situ conservation tool and a means of continuous production of in vivo and in vitro plant material for further
studies. R. tomentosum microshoots were initiated from leaf explants and further multiplied using Schenk-
Hildebrandt (SH) medium supplemented with 9.84 ÎŒM 2iP and 1.00 ÎŒM TDZ. The shoots were elongated on the
SH medium supplemented with 24.6 ÎŒM 2iP and subsequently rooted using the perlite substrate saturated with
half-strength Woody Plant medium supplemented with 1.0% sucrose and 4.92 ÎŒM IBA. The regenerated plants
were hardened on the phytohormone-free SH medium and acclimatized using 3:1:1 deacidified peat:perlite:gravel
substrate. The identity of the mother plant was confirmed at morphological and molecular levels and Random
Amplified Polymorphic DNA (RAPD) method was implemented to assess the genetic fidelity of the regenerants.
The essential oil content of the maternal plant, in vitro shoots and the regenerants was determined by steamdistillation,
and the obtained volatile fractions were analyzed by GC/MS
Assessment of Airborne Total Volatile Organic Compounds of Niagara Falls Residences as Compared to Resident Lifestyle
Is Dichloromethane a Useful Alternative to CS2 in the Extraction of Organics Sampled with Activated Charcoal Adsorbents?
Evidence and recommendations to support the use of a novel passive water sampler to quantify antibiotics in wastewaters
A novel passive water sampler (diffusive gradients in thin-films for organics, o-DGT) was previously developed and successfully tested in the laboratory, but has not yet been validated in the field. Here, o-DGT samplers were deployed in the influent and effluent of a typical UK wastewater treatment plant (WWTP); the influent was also sampled with a conventional automatic sampler (Auto) and by grab (Grab) sampling. All the samples were analyzed by LC-MS/MS for 40 target antibiotics (including 16 sulfonamides (SAs), 12 fluoroquinolones, 6 macrolides, 2 ionophores, 2 diaminopyimidines, 1 aminocoumarin, and 1 lincosamide). The diffusion coefficients (D) of these antibiotics in o-DGT, measured in the laboratory, ranged from 0.58 Ă 10â06 to 6.24 Ă 10â06 cm2 sâ1. The derived surface area normalized sampling rates (RS/A, 0.54â5.74 mL dâ1 cmâ2) were comparable with those for another passive sampler called POCIS. Fourteen antibiotics were detected in the actively sampled water samples, with 10 of the 14 detected in o-DGT devices deployed for more than 7 days. Most of the antibiotics detected in o-DGT, except sulfapyridine, were continually accumulated by o-DGT for 10 days. Deployment for 7 days is recommended to integrate ambient concentrations over time, without risks of reaching capacity and significant biofouling. Diffusive boundary layer (DBL) thickness had less effect on the o-DGT measurement than reported for other passive samplers. The comparison between o-DGT and Auto and Grab samplings showed that o-DGT was more efficient in terms of cost, time, and labor. This study demonstrates for the first time in a real environment that o-DGT is an effective tool for the routine monitoring of antibiotics in wastewaters and provides a powerful approach to studying their occurrence, fate, and behavior in the environment