## 4 Discussion
fragile_ (Argentina) were composed mostly of galactose and arabinose with minor quantities of xylose, mannose, and glucose, and with a high content of sulfates (20.6%) and proteins (11.3%). This indicates the occurrence of low amounts HRGP epitopes as well as pyruvate arabinocaltan sulfates (pAGS) [16]. Similar cell wall structures have been found in the green seaweed _C. vermilara_, which was composed of small amounts of hydroxyproline-rich glycoprotein-like (HRGP-L) [21]. The yield, structure, chemical composition, and content of polysaccharides in seaweed varied among each species, depending on the age, season, geographic location, and climatic conditions, as well as the extraction processes [45]. Conventional extraction of the cell wall SPs from _Codium_ sp. is typically performed using wateras a solvent under specific temperature conditions for several hours. As discussed earlier, when the aqueous extraction was performed at room temperature, sulfate AGPs were the main obtained polysaccharides from _C. fragile_; however, when hot water was used (i.e., 90 \({}^{\circ}\)C for 3 h), the major components were sulfated mannans [16]. The extraction of sulfated mannans with hot water was also confirmed in previous works using _C. vermilara_[14] and _C. fragile_[46]. The difference in the monosaccharide composition of _Codium_ sp. extracts seems to be related to the extraction procedure; thus, the sulfated arabinadicans and arabinans seem to have a high solubility in water at room temperature and the sulfated mannans in hot aqueous temperature [11; 46]. It was reported that the M\({}_{\mathrm{w}}\) of water-soluble polysaccharides isolated from _C. fragile_ was in the range of 148-4879 kDa, including a subfraction with an M\({}_{\mathrm{w}}\) of 2017 kDa [46]. These are in accordance with the M\({}_{\mathrm{w}}\) of the AGB and AGP fractions from _C. decorticatum_ obtained in this work. However, several studies revealed that the SPs extracted from _C. vermilara_, _C. fragile_, and _C. isthmocladatum_ were characterized by a low M\({}_{\mathrm{w}}\), ranging from 10 to 140 kDa [6; 11; 14; 47; 48]. The green seaweed _Ulva_ sp. is commonly known as a source of ulvans; nevertheless, [PERSON] et al. reported for the first time the presence of AGP-like glycoproteins in _Ulva lactuca_ with an M\({}_{\mathrm{w}}\) ranging from 100 to 250 kDa [49]. The structural features of cell wall polysaccharides from _C. decorticatum_ collected along the Patagonic coast (Argentina) revealed the presence of 6.9% of soluble and 32.9% of fibrillar carbohydrates [50]. Four water soluble polysaccharides were detected, as well as pyruvate and sulfated galactans, sulfated arabinans, and mannans with a low degree of sulfation. Besides this, HRGPs were co-localized with the fibrillar components [50]. In line with the present work, a glycoprotein (GLP) has been isolated from _C. decorticatum_ (India) containing 36.24% of carbohydrates [51]. It was characterized by a molecular mass of 48 kDa and the presence of rhamn, galactose, glucose, and mannose as the main monosaccharides [51]. Compared to the terrestrial plants, the M\({}_{\mathrm{w}}\) of the type II arabinadicans varied from 10.4 to 3780 kDa [19]. The glycoproteins purified from _C. decorticatum_ showed some similarity in terms of chemical and structural compositions with the AG-type II found in land plants [19]. Therefore, the green alga _C. decorticatum_ could be exploited as a source of sulfated arabinadicans-rich protein and might be an alternative to terrestrial plants, due to its abundance, the important yield of cell wall AGPs, and the facility of the extraction procedure, which uses only water as an extractant. In order to investigate the elictor capacities of the sulfated glycoproteins isolated from _C. decorticatum_, the crude and purified extracts (AGB and AGP) were foliar sprayed and injected in 45-day-old tomato seedlings.