α v) is the absorption coefficient defined by the Beer Lambert's law as follows: alpha = frac{{2.303 {text{Abs}}.}}{d} (8 where d and Abs. are the optical path (1 cm) and absorbance of Ag colloids, respectively.
Cells suspended in fresh BG11 medium containing 2 mM NaHCO3 were incubated in a temperature-controlled Perspex holder (optical path 1.5 cm, 25°C).
The absorbance at 295 nm was converted to the ellipticine concentration using Beer-Lambert's law: absorbance (Abs) = εcd, where ε is the molar extinction coefficient, c is the molar concentration of ellipticine, and d is the optical path length (cm) [37].
For a 100 ha production plant using flat panel photobioreactors (optical path 3 cm), investment costs were estimated to be 0.8 M€/ha [ 3].
The Erlenmeyer flasks were used as inoculum for cultivation in a 4.5 L flat panel photobioreactor (optical path 2.5 cm); pH was controlled at 7.5 by on demand CO2 addition, temperature was controlled at 25 °C and mixing by aeration at 1.5 L−1.5−1.5in−1.5
The UV reactor consisted of a 1 L brown glass bottle (Veffective = 925 mL) containing a low-pressure UV lamp (arc length = 16.5 cm, optical path length = 4.3 cm) used typically for swimming pool disinfection (G23 Odyssea Pool Lamp, 9W, Odyssea Aquarium Appliance Co., Ltd., Guangdong, China; Figure S1, Supporting Information).
UV-visible-near-infrared (NIR) absorption spectrometer was measured in a 1-cm-quartz cuvette with an optical path of 1 cm using a PerkinElmer Lambda 950 spectrophotometer.
A quartz cuvette with an optical path of 0.25 cm was used for the optical absorption measurements.
Far-UV CD spectra were recorded on a JASCO J-710 spectropolarimeter at 25°C over the 195 250 nm spectral range, with an optical path of 0.2 cm.
Near-UV spectra were recorded over the 250 310 nm spectral range, with an optical path of 0.2 cm and lipase concentration of 1 mgml-1 of 20 mM phosphate buffer (pH 7.0).
