Shiitake mushroom contains several therapeutic actions such as antioxidant and antimicrobial properties, carried by the diversity of
its components. In the present work, extracts from shiitake mushroom were obtained using different extraction techniques: high-pressure
operations and low-pressure methods. The high-pressure technique was applied to obtain shiitake extracts using pure CO2 and
CO2 with co-solvent in pressures up to 30 MPa.
A new automated procedure for preconcentration and analysis of anionic surfactants in water using solid-phase extraction (SPE) in a flow injection (Fl) system together with an UV-vis detection is reported in this paper. The method involves extraction of blue coloured ion-pair complex of anionic surfactants and methylene blue into solid phase and their elution from the SPE column with organic solvent (chloroform stabilised with methanol) and subsequent measurement in an UV-vis flow cell at 650 nm. The system is well optimised before to apply for analysis of real samples.
Addition of Surrogates and Matrix Spiking Compounds in the Field: It is best to
add analytical surrogate and matrix spiking compounds into soils prior to sample
extraction, using water or a solvent. Method 5035A does not incorporate the addition
of these compounds prior to extraction in the field. Because this is an important
control check on the analytical process, it may be appropriate to incorporate a
procedure which adds surrogate and/or matrix spiking compounds prior to extraction
for some project/program DQOs.
The interaction of tungsten(VI) with CV has been investigated in acetone-aqueous medium. The complex has been examined by solvent extraction-spectrophotometry method. In optimum conditions (pH 3; 30% acetone v/v) the ion-association complex of tungsten(VI) with CV was formed with ratio of 2 : 1, and it was extracted quantitatively one time with 5 mL toluene. In organic phase, the complex has maximum absorption at 599 nm with = 11.2 x 104 L.mol -1 .cm-1 , and stable at least 2 hours after extraction.