Rock Samphire, a Candidate Crop for Saline Agriculture: Cropping Practices, Chemical Composition and Health Effects

Sea Fennel (Crithmum maritimum L.) as an Emerging Crop for the Manufacturing of Innovative Foods and Nutraceuticals

Sea fennel (Crithmum maritimum L.) is a perennial, strongly aromatic herb that has been used since ancient times in cuisine and folk medicine due to its renowned properties. Recently described as a "cash" crop, sea fennel is an ideal candidate for the promotion of halophyte agriculture in the Mediterranean basin due to its acknowledged adaptation to the Mediterranean climate, its resilience to risks/shocks related to climate changes, and its exploitability in food and non-food applications, which generates an alternative source of employment in rural areas. The present review provides insight into the nutritional and functional traits of this new crop as well as its exploitation in innovative food and nutraceutical applications. Various previous studies have fully demonstrated the high biological and nutritional potential of sea fennel, highlighting its high content of bioactive compounds, including polyphenols, carotenoids, ω-3 and ω-6 essential fatty acids, minerals, vitamins, and essential oils. Moreover, in previous studies, this aromatic halophyte showed good potential for application in the manufacturing of high-value foods, including both fermented and unfermented preserves, sauces, powders, and spices, herbal infusions and decoctions, and even edible films, as well as nutraceuticals. Further research efforts are needed to fully disclose the potential of this halophyte in view of its full exploitation by the food and nutraceutical industries.

Soil physicochemical properties associated with the yield and phytochemical composition of the edible halophyte Crithmum maritimum

There is growing interest in the consumption of halophytes due to their excellent nutritional profile and antioxidant properties, and their cultivation offers viable alternatives in the face of irreversible global salinization of soils. Nevertheless, abiotic factors strongly influence their phytochemical composition, and little is known about how growing conditions can produce plants with the best nutritional and functional properties. Crithmum maritimum is an edible halophyte with antioxidant properties and considerable potential for sustainable agriculture in marginal environments. However, it is found naturally in contrasting habitats with variable soil physicochemical properties and the extent to which edaphic factors can influence plant performance, accumulation of phytochemicals and their quality remains unknown. We investigated the influence of soil physicochemical properties (texture, pH, electrical conductivity, organic matter content and mineral element concentrations) on growth and reproductive performance, nutritional traits, and the accumulation of specific metabolites in C. maritimum. Soil, leaf and seed samples were taken from eight C. maritimum populations located on the southern coasts of Spain and Portugal. We found greater vegetative growth and seed production in coarser, sandier soils with lower microelement concentrations. The nutritional traits of leaves varied, with soil organic matter and macronutrient content associated with reduced leaf Na, protein and phenolic (mainly flavonoid) concentrations, whereas soils with lower pH and Fe concentrations, and higher clay content yielded plants with lower leaf Zn concentration and greater accumulation of hydroxycinnamic acids. The nutritional value of the seed oil composition appeared to be enhanced in soils with coarser texture and lower microelement concentrations. The accumulation of specific phenolic compounds in the seed was influenced by a wide range of soil properties including texture, pH and some microelements. These findings will inform the commercial cultivation of C. maritimum, particularly in the economic exploitation of poorly utilized, saline soils.

Exploiting the Crithmum maritimum L. Aqueous Extracts and Essential Oil as Potential Preservatives in Food, Feed, Pharmaceutical and Cosmetic Industries

Chritmum maritimum, sea fennel, is a facultative halophyte used in salads, soups, and sauces, as well as used to prepare medicinal juices and aqueous extracts (AE) to treat several ailments. Its essential oil (EO) is used as a spice and aromatizing. In this work, the nutritional (crude protein, fiber, lipids, and ashes content) and HPLC-PDA phenolic profiles were determined. Furthermore, the antioxidant potential of the infusion and of the decoction, as well as the antibacterial activity of both, the AE and EO, were assessed against food-contaminating bacteria. The composition of the EO was also established. Sea fennel exhibited considerable fiber (34.3 ± 1.92%) and mineral content (23.6 ± 4.8%). AE contains chlorogenic acid as the major phenolic compound, 49.7 ± 0.8 mg/g in the infusion dry extract and (26.8 ± 0.9 mg/g in the decoction dry extract). EO contains high amounts of monoterpene hydrocarbons, namely γ-terpinene and sabinene. In regards to the antioxidant activity, IC₅₀ values for the infusion and decoction were, respectively: 36.5 ± 1.4 μg/mL and 44.7 ± 4.4 μg/mL in the DPPH assay; 37.3 ± 2.6 μg/mL and 38.4 ± 1.8 μg/mL, in the ABTS assay. EO is particularly active against Bacillus cereus and Lactobacillus plantarum. The results support the use of sea fennel AE and EO as a potential alternative preservative ingredient for feeds, foods, pharmaceutical, and cosmetic industries, due to the antioxidant activity of infusion and decoction, and antibacterial properties of essential oil.

Chemical Profiling of Sea Fennel (Crithmum maritimum L., Apiaceae) Essential Oils and Their Isolation Residual Waste-Waters

Sea fennel (Crithmum maritimum L.) is a wild-growing halophyte used in cuisine, traditional medicine or cosmetic products for its beneficial nutritive value and pleasant sensory characteristics. This study aimed to investigate sea fennel essential oils (EOs) from different parts of the plant (flowers, leaves and stems) and the corresponding hydrodistillation by-products (residual water) to validate their potential use and application in different industries. EOs were analyzed by gas chromatography coupled with mass spectrometry (GC-MS), while the phenolic profile of the residual water was analyzed by high-performance liquid chromatography (HPLC) and spectrophotometric methods. The EO analysis confirmed the presence of 14 compounds, dominated by sabinene (from 42.55 to 51.47%) and limonene (from 36.28 to 43.58%), while among the 12 detected phenolics, chlorogenic acid and its isomers (cryptochlorogenic and neochlorogenic acid) were found in the highest concentrations. Total phenolic, flavonoid and tannin contents were concentrated in the order flowers > leaves > stems. Although the sea fennel samples showed differences in chemical profiles, overall they were rich in bioactive compounds with relatively high amounts of key compounds with already proved good biological properties, especially in waste-water, indicating great potential for re-use in accordance with green processing technology trends.

The Edible Plant Crithmum maritimum Shows Nutraceutical Properties by Targeting Energy Metabolism in Hepatic Cancer

In the past few years, evidence has supported the role of plants as a valuable tool for the development of promising therapeutic support options for many diseases, including cancer. We recently discovered that the edible wild plant Crithmum maritimum L. effectively inhibits the growth of hepatocellular carcinoma (HCC) cells and we provide insights into the biological mechanisms involved. Here, we aimed to characterize the effect of ethyl acetate extract of Crithmum maritimum on the bioenergetic phenotype of HCC cells and if this is associated with the anti-tumour effect we previously described. Results show that Crithmum maritimum significantly increases cellular respiration and reduces lactic fermentation in HCC cells, and that this reduction of the fermentative glycolytic phenotype is linked to inhibition of HCC growth. These data provide new preclinical evidence supporting the role of Crithmum maritimum L. as a nutraceutical option to expand the therapeutic opportunities in the management of HCC.

Using the Halophyte Crithmum maritimum in Green Roofs for Sustainable Urban Horticulture: Effect of Substrate and Nutrient Content Analysis including Potentially Toxic Elements

The effect of substrate type and cultivation site in the urban fabric on growth, nutrient content and potentially toxic element (PTE) accumulation in tissues of the halophyte Crithmum maritimum was studied. Plantlets were cultivated for twelve months in containers with a green-roof infrastructure fitted and placed either on an urban second-floor roof or on ground level by the side of a moderate-traffic street. Two substrate types were used; one comprising grape marc compost, perlite and pumice (3:3:4, v/v) and one composed of grape marc compost, perlite, pumice and soil (3:3:2:2, v/v), with 10 cm depth. Plants grew well on both sites, although aboveground growth parameters and nutrient content in leaves were greater at street level. Both cultivation site and substrate type affected heavy-metal accumulation in plant tissues. Cu, Ni and Fe concentrations in leaves and Pb in roots were higher in street-level-grown plants compared to the roof-grown plants, and concentrations of Cu and Mn in leaves and Fe in both leaves and roots were lower in the soilless substrate compared to the soil-substrate, making the soilless type preferable in the interest of both safer produce for human consumption and lower construction weight in the case of green-roof cultivation.