Gc 2014 gas chromatograph

Red and green mango fruit cv. Shelly were stored at 5, 8 or 12 °C. Eight red-colored and eight green-colored fruit were enclosed in glass jars (one fruit per jar). The respiration production rates of the mango fruit were measured by closing the bottles for 1 h. Samples were taken using syringes and subsequently analyzed by GC for CO₂ (GC-2014 gas chromatograph, Shimadzu, Tokyo, Japan) and for ethylene (Varian Model 3300 GC, Agilent Technologies, Santa Clara, CA, USA). The respiration rate was measured after harvest, and after 1 week and 3 weeks in cold storage.

The dialysate and lumen fractions of TIM-2 were analyzed with gas chromatography for SCFA (acetate, propionate and butyrate) and BCFA (iso-butyric acid and iso-valeric acid).
For SCFA/BCFA, samples were prepared and analyzed as described previously [10 (link)]. Briefly, dialysate samples were directly used, lumen samples were centrifuged (12,000 rpm at 4 °C for 10 min). A mixture of formic acid (20%), methanol, and 2-ethyl butyric acid (internal standard, 2 mg/mL in methanol) was added to the supernatant. A 3 μL sample with a split ratio of 75.0 was injected on a GC-column (ZB-5HT inferno, ID 0.52 mm, film thickness 0.10 um; Zebron; Phenomenex, Utrecht, The Netherlands) in a Shimadzu GC-2014 gas chromatograph (Shimadzu Europe, Duisburg, Germany).

The physical and chemical parameters of the groundwater were measured at the groundwater outflow of the deep well. Temperature was measured with a CT-460WR thermometer (Custom, Tokyo, Japan). Oxidation-reduction potential (ORP) and pH were measured with RM-20P and HM-20P portable meters (DKK-TOA, Tokyo, Japan), respectively. Electric conductivity (EC) was measured with a CM-21P portable meter (DKK-TOA). Concentrations of natural gas were determined on a GC-2014 gas chromatograph (GC) equipped with a thermal conductivity detector (TCD) and a flame ionization detector (Shimadzu, Kyoto, Japan) following the procedures described by Matsushita et al. [10 (link)].
The concentrations of anions (Cl⁻, Br⁻, I⁻, F⁻, PO₄³⁻, NO₃⁻, SO₄²⁻, HCO₃⁻, acetate, and formate) and cations (Na⁺, Ca²⁺, Mg²⁺, K⁺, and NH₄⁺) in the groundwater were analyzed with an ICS-1500 ion chromatography system (Dionex, Sunnyvale, CA, USA). Sulfide was analyzed by a sulfide ion detector (Gastech, Ayase-Shi, Kanagawa, Japan). Dissolved organic carbon (DOC) in the groundwater filtered through pre-combusted GF/F glass microfiber filters (GE Healthcare, Buckinghamshire, UK) was measured with a TOC-V total organic carbon analyzer (Shimadzu).

Samples of fat (200 g; 65% abdominal fat and 35% gizzard fat, the normal fat proportions of the carcass) were dried and extracted following the Soxhlet procedure and using diethyl ether as the extraction solvent [11 ]. The methyl esters from fatty acids (FAME) were prepared using BF₃ in methanol and stored at −80 °C until chromatographic analysis.
The FAME were analysed using a gas chromatograph (GC-2014 Gas Chromatograph, Shimadzu, Chiyoda-ku, Tokyo, Japan) equipped with a flame ionization detector, a split/splitless injector, and a fused silica capillary column containing polyethylene glycol as stationary phase (db-wax, 60 m × 0.25 mm, J&W Scientific, Santa Clara, CA, USA). The injector temperature was set to 230 °C. The initial column temperature was 80 °C for 2 min at a rate of 3 °C per minute, was raised to 180 °C at 30 °C per minute and was kept at this temperature for 30 min. After this time, the temperature was increased to 200 °C at a rate of 3 °C per minute and remained at this temperature for 108 min. The fatty acids were quantified using C11:0 methyl ester as internal standard. Identification of fatty acids was performed by comparison of the retention times with those of known fatty acids and the results expressed as percentage of the area of each fatty acid over the total area of fatty acids (%).

We collected 2 mL of fresh culture, which we then centrifuged at 10,000× g for 15 min. The supernatants were filtered (filter with 0.2 µm pores) and stored at −20°C until analysis. Samples for short-chain fatty acid (SCFA) analyses were collected after 16, 22, and 40 h. SCFAs were extracted from the samples in diethyl ether, after the addition of 2-methyl hexanoic acid as an internal standard. Extracts were analyzed with a GC-2014 gas chromatograph (Shimadzu, ’s-Hertogenbosch, The Netherlands), equipped with a capillary fatty acid-free EC-1000 Econo-Cap column (dimensions: 25 mm × 0.53 mm, film thickness: 1.2 mM; Alltech, Laarne, Belgium), a flame ionization detector and a split injector.