Whatman grade 1

Phosphate buffered saline (1X PBS, without calcium and magnesium, pH 7.4, Cellgro, Manassas, VA, USA) solution containing 37 mM NaCl, 2.7 mM KCl, 10 mM Na₂HPO₄, 1.8 mM KH₂PO₄ and potassium ferricyanide (PF, 99+%, for analysis, ACROS Organics^TM, Morris, NJ, USA) was purchased from Fisher Scientific. All chemicals were used as received without further purification. Silver foil (Alfa Aesar, Haverhill, MA, USA, 0.10 mm thickness, 99.998% pure, annealed) and platinum foil (Alfa Aesar, 0.127 mm thickness, 99.99%, Premion^®) were used for reference and counter electrodes. Chromatographic cellulose filter paper (Whatman grade 1, 0.18 mm thickness, WhatmanTM, Florence, SC, USA) was used for the paper-based Origami cell construction. Circuit paper (AgIC International Corp., Tokyo, Japan) was used for printing the silver conductive pathway.

Hop (H. lupulus L.) pellet samples of four different varieties
(Cascade, Saaz, Tettnang, and Summit) were selected according to their
widespread use in brewing production and obtained from a local beer
producer (Menaresta Brewery, Carate Brianza, Italy). Hop pellets (2
g) were extracted in (a) boiling water (200 mL) for 2 h or (b) hydroalcoholic
solution (10% ethanol in water) at 30 °C for 24 h under magnetic
stirring. The suspension was filtered on a cotton and paper filter
(Whatman grade 1, pore size 11 μm) and, finally, the permeate
was concentrated under reduced pressure. Residues were freeze-dried,
and samples were stored at −20 °C until use.

The olive samples were coarsely crushed with the help of a hammer. A representative aliquot of the solid samples (olives, olive paste, residual pomace) was then dried in an oven at 75 °C for 12 h to remove moisture and thus facilitate solvent extraction. Next, the samples were ground, and a 15 g aliquot was added to 40 mL of hexane and subjected to ultrasound-assisted extraction for 1 h in the case of olive samples and 2 h in the case of pomace samples. The extract was then filtered on paper (Whatman™ Grade 1), collected in a flask along with the washes (5 × 3 mL of hexane), and, finally, the solvent was removed from the extracted oil by means of a rotary evaporator until a constant weight was achieved.

Sample preparation procedure was reported in previous study [12]. Briefly, PDMS was dissolved in THF so that a dilute solution of 0.7% PDMS by weight was obtained, into which three types of filler particles were added, each equivalent in weight to PDMS, so that weight of the filling materials in the mixture corresponded to 3 times the weight of PDMS (Table 1). The dispersion mixture was mixed with a magnetic stirrer and then in an ultrasonic bath and transferred to the tank of the spray gun without delay. The dispersion mixture was applied onto Whatman Grade 1 with a spray gun while the distance between the spray gun nozzle and the paper substrate was kept constant. Afterwards, the samples were left in the hood overnight for the evaporation of the THF solvent. Samples were then heat-treated at 120 °C for 36 h. After the heat treatment step, samples were left to cool to 23 °C. Soxhlet extraction with THF was performed to get rid of the excess/unreacted PDMS.
At least 10 samples were prepared for each of the above listed sample sets. It is important to note that the PDMS/GS/aero/N20 sample has a similar composition with those of the samples prepared in our previous study. The aim of preparing PDMS/GS/aero/N20 is to be able to compare the properties of the 6 above mentioned sample sets having different coating formulations with each other and with WFP control.

C. uda has the capability of expressing cellulose and hemicellulose degrading enzymes [11 (link), 12 (link), 58 (link)]. The cellulase activity of the fermentation broth was measured by a filter paper assay as described previously for a general approach [59 ]. Nevertheless, the assay was adjusted to the requirements of the present process as follows: (I) 0.2 M MOPS buffer pH = 7.4 was applied instead of citrate buffer and (II) 6 cm⁻² of filter paper (Whatman grade 1, Whatman plc, Little Chalfont, United Kingdom), 1 mL MOPS buffer and 1 mL of culture broth were incubated at 313 K and 1400 rpm for 240 min (Thermomixer‐compact, Eppendorf AG, Hamburg, Germany).
The xylanase activity was determined according to Rapp and Wagner [12 (link)] with some modifications: (I) 0.05 M sodium citrate buffer pH = 5 was applied instead of phosphate buffer in order to produce the 0.7 w% xylan testing solution and (II) 1 mL of culture broth and 1 mL of xylan solution were incubated at 323 K for 90 min.
The enzymatic reaction was stopped after the incubation period by heating up the sample to 368 K for 10 min. Sugar concentrations (cellobiose and xylose) were determined using HPLC, as described in the supporting information.
The enzymatic activity A, both for cellulase and for xylanase, was determined according to the Equation (2).
$$\begin{array}{c}\hfill A=\frac{(c_{Sugar,Assay}-0.5·c_{Sugar,Fermentation})·V_{Assay}}{M_{Sugar}·t_{Assay}}·16.67\end{array}$$