## 5 Chlorophylls  
Chlorophylls (chlorophyll \(a\) and chlorophyll \(b\)) are photosynthetic pigments responsible for the green colour of plants. In human nutrition, chlorophyll has antioxidant activity, and the rich colour makes products more desirable for consumption [6; 63; 64]. It has also been shown to have anti-cancer properties, as it can interfere with the absorption of some carcinogenic compounds in the gastrointestinal tract [65]. Chlorophyll-derivative chlorophyll is also registered as a food additive and natural colourant (E140i), and pigment concentrates can be extracted from edible plants using organic solvents [66]. Most of the studies determine the concentration of pigments as a basis of the dry weight or fresh weight (FW) of the biomass. When considering FW, it is important to note that succulent halophytes, in particular, have a high moisture content which can exceed 80% of the fresh weight [6; 67]. The amount of pigment can also be determined based on leaf surface area: [PERSON] et al. [68] applied this method in their study of photosynthesis of _Aster triplolium_. Spectrophotometric methods are widely used to determine the amount of chlorophyll in halophyte extracts. Most of the reviewed studies use the technique introduced by [PERSON] et al. [69], where wavelengths are used for measuring absorbance, and the conversion coefficients depend on the solvent used. [PERSON] et al. [67] and [PERSON] et al. [70] used a novel quantification technique after ultrasound-assisted acetone extraction which involved applying the Gauss peak spectra method developed by [PERSON] et al. [71] instead of traditional spectroscopic methods. Some HPLC methods are also available for pigment determination. The method by [PERSON] et al. [72] was firstly developed for marine algae biomass, and it uses a C8 column with methanol, acetonitrile, and acetone (50:25:25 v%) as the mobile phase. As seen from Table 3, among halophyte species, the highest chlorophyll content in fresh biomass were found in acetone extracts of _Salicornia europaea_ and _Salicornia persica_ (approximately 1.25 mg/gFW and 2.21 mg/gFW, respectively) [73]. Values are relatively high compared to other species. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Plant Species** & **Solvent** & **Method** & **Concentration** & **Unit** & **Ref.** \\ \hline _Arthrocenmun macostachyatum_ & Acetone/hexane & & 28.3 \(\pm\) 7.1 & mg/100 gDM & [6] \\ \hline _Aster triplolium_ & Ethanol & & -51 & mg/cm\({}^{2}\) & [68] \\ \hline _Hilimonite portulosulos_ & Acetone & & 95.04 \(\pm\) 23.47 & \(\mu\)g/gFW & [67] \\ \hline _Meschmypartheimn modifiern_ & Methanol & Spectrophotometry & -280 & mg/100 gDM & [32] \\ \hline _Salicornia tigolevii_ & Acetone & & 569.1 \(\pm\) 9.10 & mg/kgFW & [22] \\ \hline _Salicornia brachiata_ & Acetone & & 746.5 \(\pm\) 88.2 & \(\mu\)g/gDM & [77] \\ \hline _Salicornia europaea_ & Acetone & & -1.25 & mg/gFW & [73] \\ \hline _Salicornia nexi_ & Methanol & HPLC & 233.3 \(\pm\) 42.5 & \(\mu\)g/gDM & [78] \\ \hline _Salicornia pesica_ & Acetone & & -1.21 & mg/gFW & [73] \\ \hline _Salicornia pesica_ & Acetone & & -325 & \(\mu\)g/gFW & [63] \\ \hline _Salicornia prestrata_ & Acetone & & -0.14 & mg/gFW & [79] \\ \hline _Salicornia numississima_ & Acetone/hexane & & 21.56 \(\pm\) 3.45 & mg/100 gDM & [6] \\ \hline \multirow{4}{*}{_Sarrocornia fruitosa_} & Methanol & & -290 & mg/100 gDM & [32] \\ \cline{2-5}  & Acetone & & 102.01 \(\pm\) 18.23 & \(\mu\)g/gFW & [67] \\ \cline{2-5}  & Acetone & & -350 & \(\mu\)g/gFW & [63] \\ \cline{1-1} \cline{2-5}  & & 14.78 \(\pm\) 2.33 & mg/100 gDM & [4] \\ \hline _Suanda murima_ & Methanol & & -280 & mg/100 gDM & [32] \\ \hline _Suanda prostrata_ & Acetone & & -0.08 & mg/gFW & [79] \\ \hline _Tamuric gallica_ & Acetone & & -180 & mg & [70] \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Total chlorophyll content measured from halophyte biomasses. Studies that used spectrophotometry applied the method by [PERSON] et al. [69], except [PERSON] et al.