Towards the Sustainable Exploitation of Salt-Tolerant Plants: Nutritional Characterisation, Phenolics Composition, and Potential Contaminants Analysis of Salicornia ramosissima and Sarcocornia perennis alpini

Abstract

Increasing soil salinisation represents a serious threat to food security, and therefore the exploitation of high-yielding halophytes, such as Salicornia and Sarcocornia, needs to be considered not merely in arid regions but worldwide. In this study, Salicornia ramosissima and Sarcocornia perennis alpini were evaluated for nutrients, bioactive compounds, antioxidant capacity, and contaminants. Both were shown to be nutritionally relevant, exhibiting notable levels of crude fibre and ash, i.e., 11.26–15.34 and 39.46–40.41% dry weight (dw), respectively, and the major minerals were Na, K, and Mg. Total phenolics thereof were 67.05 and 38.20 mg of gallic acid equivalents/g extract dw, respectively, mainly p-coumaric acid and quercetin. Both species displayed antioxidant capacity, but S. ramossima was prominent in both the DPPH and ß-carotene bleaching assays. Aflatoxin B1 was detected in S. ramosissima, at 5.21 µg/Kg dw, which may pose a health threat. The Cd and Pb levels in both were low, but the 0.01 mg/Kg Hg in S. perennis alpini met the maximum legal limit established for marine species including algae. Both species exhibit high potential for use in the agro-food, cosmetics, and pharmaceutical sectors, but specific regulations and careful cultivation strategies need to be implemented, in order to minimise contamination risks by mycotoxins and heavy metals.

Salicornia emerici Duval-Jouve and Sarcocornia alpini (Lag.) Rivas Mart. from Southern Tunisia: Potential Sources of Functional Ingredients with Nutritional and Health Promoting Benefits

“…. The levels of chlorogenic and p-coumaric acids, rutin and quercetin were lower than those reported for Salicornia ramosissima and S. perennis alpini [19]. The same was observed for chlorogenic acid and quercetin contents in S. alpini when compared to the results of wild S. fruticosa extracts from Spain and Portugal, while its rutin content was higher [36].…”

“…The TPC of S. alpini exceeded the levels previously reported in methanolic extracts of S. alpini gathered from different locations across the Iberian Peninsula, which ranged from 3.43 to 3.77 mg GAE/g DW [33]. For the same species collected from Portugal, Lopes et al ( 2023) reported higher values (38.2 mg GAE/g DW) [19]. S. alpini exhibited higher TPC, similar TFC, and lower CTC than wild S. fruticosa [36].…”

“…These compounds can exhibit varying reactions to individual antioxidant mechanisms, contingent on their respective a nities, thus yielding distinct activity patterns [77,78]. Hence, the use of several assays to evaluate the antioxidant activity of natural extracts is recommended [19,79,80]. Nevertheless, one should not exclude the potential effect of non-identi ed phytochemicals present in the extracts.…”

“…Several studies have highlighted halophytes' potential as novel sources of nutrients including minerals, vitamins, and polyunsaturated fatty acids [14][15][16]. Besides, halophytes are becoming increasingly attractive in modern agriculture due to their ability to thrive in challenging conditions of high salinity and water scarcity, which is particularly relevant in the Mediterranean region, especially in Tunisia, where climate change in recent years has exacerbated these issues [17][18][19]. The Salicornioideae subfamily (Amaranthaceae) encompasses approximately 100 succulent halophytic plant species found in coastal and inland saline regions worldwide including Sarcocornia and Salicornia species which are morphologically and taxonomically similar and can only be distinguished by in orescence characters and life form with Sarcocornia being perennial and Salicornia being annual [20,21].…”

“…Introducing biosaline agriculture systems would allow for the direct harvesting and consumption of fresh, edible tips as food. Simultaneously, the non-food-grade biomass can be repurposed through biore nery processes resulting in bio-products with high-value applications, such as nutraceuticals and functional ingredients [19,30].…”