*2.2. Measurement of the Chlorophyll Contents in the Extracts*

The amounts of total chlorophylls in the extracts were estimated by the following method [41]: First, 1.4 g of sodium oxide was dissolved in 40 mL of distilled water and 16.6 g of pyridine was added to make 100 mL of the final volume. Then, 10 mg of the extract was placed in a foil-covered test tube and added with 10 mL of distilled water, and further incubated for 30 min. Thereafter, 2 mL of the suspension was mixed with 5 mL of an alkaline pyridine solution and incubated at 60 ◦C with aluminum foiled cover, and then allowed to stand for 15 min. After that, the solution was centrifuged at 3000× *g* for 3 min. and the supernatant was transferred to a 10 mL brown flask and stored in a cool place. Then, the absorbance of the sample solution was compared with that of alkaline pyridine solution by a UV spectrophotometer (UTX-20M, Biostep co., Burkhardsdorf, Germany) at 419 nm and 454 nm of wavelengths. The actual concentrations in the extracts were estimated by the following Equation (1):

$$\text{Total chlorophyll} \text{ (mg/100 g)} = \text{C/S} \times 100. \tag{1}$$

C: Chlorophyll (mg/L) = 8.970 × (7.19 × A419 nm + 3.33 × A454 nm)

S: Weight (mg) of the extracted sample in 2 mL of alkaline pyridine solution

A419 nm: Absorbance at a wavelength of 419 nm

A454 nm: Absorbance at a wavelength of 454 nm
