The essentiality of selenium (Se) and iodine (I) to human beings and the widespread areas of selenium and iodine deficiency determine the high significance of functional food production with high levels of these elements. In this respect, joint biofortification of agricultural crops with Se and I is especially attractive. Nevertheless, in practice this topic has raised many problems connected with the possible utilization of many Se and I chemical forms, different doses and biofortification methods, and the existence of wide species and varietal differences. The limited reports relevant to this subject and the multiplicity of unsolved questions urge the need for an adequate evaluation of the results obtained up-to-date, useful for developing further future investigations. The present review discusses the outcome of joint plant Se–I biofortification, as well as factors affecting Se and I accumulation in plants, paying special attention to unsolved issues. A particular focus has been given to the prospects of herb sprouts production enriched with Se and I, as well as the interactions between the latter microelements and arbuscular-mycorrhizal fungi (AMF).

Production of functional food with high levels of selenium (Se) and iodine (I) obtained via plant biofortification shows significant difficulties due to the complex interaction between the two elements. Taking into account the known beneficial effect of silicon (Si) on plant growth and development, single and joint foliar biofortification of chervil plants with potassium iodide (150 mg L−1) and sodium selenate (10 mg L−1) was carried out in a pot experiment with and without Si nanoparticles foliar supplementation. Compared to control plants, nano-Si (14 mg L−1) increased shoot biomass in all treatments: by 4.8 times with Si; by 2.8 times with I + Si; by 5.6 times with Se + Si; by 4.0 times with I + Se + Si. The correspondent increases in root biomass were 4.5, 8.7, 13.3 and 10.0 times, respectively. The growth stimulation effect of Se, I and I + Se treatments resulted in a 2.7, 3.5 and 3.6 times increase for chervil shoots and 1.6, 3.1 and 8.6 times for roots, respectively. Nano-Si improved I biofortification levels by twice, while I and Se enhanced the plant content of each other. All treatments decreased nitrate levels, compared to control, and increased the photopigment accumulation. Improvement of total antioxidant activity and phenolic content was recorded only under the joint application of Se + I + Si. Foliar nano-Si treatment affected other element content in plants: decreased Na+ accumulation in single and joint supplementation with Se and I, restored Fe, Mn and Cr amount compared to the decreased levels recorded in separately Se and I fortified plants and promoted Al accumulation both with or without Se and I biofortification. The results of this research suggest high prospects of foliar nano-Si supply for enhancing both growth and joint I/Se biofortification of chervil.

Celery is one of the major nutraceutical vegetable species due to the high dietary and medicinal properties of all of its plant parts. Yield, growth and produce quality of six celery genotypes belonging to leafy (Elixir and Samurai), stalk (Atlant and Primus) or root (Egor and Dobrynya) types, as well as the distribution of biomass, sugars, mineral elements and antioxidants among the different plant parts, were assessed. Within the celery root type, cultivar Dobrynya resulted in higher yield than Egor, whereas the genotype did not significantly affect the marketable plant part production of leafy and stalk types. Leaf/petiole ratios relevant to biomass, total dissolved solids, sugars, ascorbic acid, flavonoids, antioxidant activity and ash, K, Zn, Fe, Mn, Cu and Se content were significantly affected by the celery type examined. Ash content was highest in the leaves and lowest in the roots. Celery antioxidant system was characterized by highly significant relationships between ascorbic acid, polyphenols, flavonoids, antioxidant activity and Zn. Among the celery types analyzed, the highest values of chlorophyll, Fe and Mn content as well as antioxidant activity were recorded in leaves from root genotypes, which suggests interesting nutraceutical prospects of the aforementioned plant parts for human utilization. Plants 2020, 9, 484 2 of 13 of celery gives the opportunity to prevent and treat several diseases, such as cardiovascular [6], liver and spleen diseases [7], rheumatism [8], inflammation [9], cancer [10] and gastrointestinal disorders [11]. Studies carried out on laboratory animals showed that the ethanolic extract of celery leaves increased spermatogenesis [12] and improved fertility [13,14]. In addition, celery was found to decrease glucose level and improve lipid profile in blood [15], and stabilize blood pressure [16].All parts of celery plants are edible: leaves, petioles, roots and seeds, either fresh or canned, or dry as spices [17]. In this respect, despite the wide utilization of Apium graveolens L., up-to-date research has not paid much attention to the comparative assessment of biochemical characteristics of different celery types, namely, leafy, stalk and root genotypes [2]. The investigation of Sellami et al. [3] demonstrated the peculiarities of essential oil composition of celery leaves, stalks and roots, but did not compare different celery types.Gaining a more in-depth knowledge regarding the aforementioned topics may lead to unveiling the nutrient and antioxidant accumulation potential in celery plants, which is of great importance for targeting functional food production.The present investigation was aimed to assess yield, growth and produce quality of leafy, stalk and root celery types, as well as the distribution of biomass, organic and mineral compounds, and antioxidants among the different plant parts, grown in the Northern Hemisphere. The results were frequently expressed as ratios between the variables assessed, which showed lower variability than the absolute values.as an average o...

The fragmentary literature data on Apiaceae seed antioxidant potential elicited a comparative evaluation work of seed biochemical profile between 11 species and 43 cultivars grown in similar conditions: anise, lovage, fennel, coriander, caraway, parsley, celery, dill, carrot, parsnip and chervil. Among the different solvents, temperature and duration regimes applied, 70% EtOH, 80 °C and 1 h running showed the best extraction efficiency of antioxidants. Total antioxidant activity (AOA) decreased as follows: lovage > anise > parsley > celery > fennel = dill > coriander > caraway > parsnip > carrot > chervil. Lovage, anise and fennel demonstrated the highest levels of total phenolics (TP), AOA and potassium. A positive correlation was recorded between total dissolved solids (TDS) and K and between AOA and TP content (r = 0.86 and r = 0.79 respectively, at p < 0.001). Varietal differences in AOA and TP levels were much lower than those relevant to TDS, K and water soluble protein (WSP), while the highest differences were found for selenium (Se). Two parsley cultivars showed anomalously high Se content and four dill cultivars unusually high levels of TDS and potassium. A positive correlation arose between Se and WSP levels in parsley seeds (r = 0.85 at p < 0.05).

The complex evaluation of varietal biochemical differences in rhubarb juice, pomace and roots is highly useful to develop an efficient processing technology. Research was carried out to compare four rhubarb cultivars (Malakhit, Krupnochereshkovy, Upryamets and Zaryanka) in terms of the quality and antioxidant parameters of juice, pomace and roots. The laboratory analyses showed a high juice yield (75–82%) with a relatively high content of ascorbic acid (125–164 mg L−1) and other organic acids (16–21 g L−1). Citric, oxalic and succinic acids accounted for 98% of the total acids amount. The juice of the cultivar Upryamets demonstrated high levels of the natural preservatives sorbic (36.2 mg L−1) and benzoic acids (11.7 mg L−1), which are highly valuable in juice production. The juice pomace proved to be an excellent source of pectin and dietary fiber, whose concentrations reached 21–24% and 59–64%, respectively. The total antioxidant activity decreased according to the following sequence: root pulp (161–232 mg GAE g−1 d.w.) > root peel (115–170 mg GAE g−1 d.w.) > juice pomace (28.3–34.4 mg GAE g−1 d.w.) > juice (4.4–7.6 mg GAE g−1 f.w.), suggesting that root pulp is a highly valuable antioxidant source. The results of this research highlight the interesting prospects of the complex rhubarb plant processing for the production of juice, containing a wide spectrum of organic acids and natural stabilizers (sorbic and benzoic acids), dietary fiber and pectin (juice pomace) and natural antioxidants (roots).