Spectra manager software version 2

The spectral measurements were made with a UV-Vis Perkin-Elmer Lambda25 and an FTIR Jasco 6300 spectrometer.
An ATR accessory equipped with a diamond crystal (Pike Technologies, Madison, Wisconsin, USA) allows the collection of FTIR spectra directly on a sample without any special preparation. The FTIR spectra were recorded in the region of 4000–400 cm⁻¹, with a TGS detector, and apodization Cosine. The spectral data were processed with JASCO Spectra Manager software, version 2. Samples were scanned at a 4 cm⁻¹ resolution, accumulation: 100 scans. Background reference spectra were recorded using air after every sample to minimize the interference due to carbon dioxide and water vapor in the atmosphere. Between measurements, the ATR crystal was carefully cleaned using pure acetone (Sigma-Aldrich Co., Saint Louis, MO, USA), then, it was dried with soft tissue [43 (link),44 (link),45 (link)].
All measurements were taken at room temperature (T = 23 °C). For each sample, three replicate spectra were recorded to ensure spectral reproducibility and to assess analytical precision; then, the average spectrum was complete.

A ZnSe 45° HATR (horizontal attenuated total reflectance) crystal (PIKE Technologies, Madison, WI, USA) and an FTIR-6200 JASCO spectrometer (Jasco Corp., Tokyo, Japan) equipped with a standard sample chamber, a triglycine sulphate (TGS) detector and a Ge/KBr beam splitter was used for the acquisition of spectral data. A small quantity of each seaweed sample was cut into small pieces, placed onto the crystal surface and pressed with a gripper to ensure the best possible contact with the crystal. The crystal used shows a refractive index of 2.4 and a depth of penetration of 2.0 µm at 1000 cm⁻¹. The spectra were obtained from the range of 4000 to 400 cm⁻¹ by accumulating 100 scans with a resolution of 4 cm⁻¹ and a total integration time of 2 min using Spectra Manager™ software version 2 (Jasco Corp., Tokyo, Japan). In total, 351 samples were spectroscopically analyzed, while 171 and 180 of them originated from MI and SAMS, respectively.