Valorization of Wild Edible Plants as Food Ingredients and Their Economic Value

Cistus, Acacia, and Lemon verbena Valorization through Response Surface Methodology: Optimization Studies and Potential Application in the Pharmaceutical and Nutraceutical Industries

Cistus ladanifer L., Acacia dealbata L., and Aloysia citrodora Paláu were subject to an optimization procedure for two extraction techniques (heat-assisted extraction (HAE) and ultrasound-assisted extraction (UAE)). The extracts were then analyzed by HPLC-DAD-ESI/MS for their phenolic profile (cistus-15 compounds, acacia-21 compounds, and lemon verbena-9 compounds). The response surface methodology was applied, considering four varying factors: ethanol percentage; extraction time; temperature/power; and S/L ratio, generating two responses (the major phenolic compound, or family of compounds, and the extraction yield). For cistus, both techniques optimized the extraction yield of punicalagins, with UAE proving to be the most efficient extraction method (3.22% ethanol, 22 min, 171 W, and 35 g/L). For acacia, HAE maximized the extraction of procyanidin (74% ethanol, 86 min, 24 °C, and 50 g/L), and UAE maximized the content of myricetin (65% ethanol, 8 min, 50 W, and 50 g/L). For lemon verbena, HAE favored the extraction of martynoside (13% ethanol, 96 min, 49 °C and 17 g/L) and forsythiaside UAE (94% ethanol, 25 min, 399 W, and 29 g/L). The optimal conditions for the extraction of compounds with high added value and potential for use in pharmaceuticals and nutraceuticals were defined.

The Combination of Low-Cost, Red-Green-Blue (RGB) Image Analysis and Machine Learning to Screen for Barley Plant Resistance to Net Blotch

Challenges of climate change and growth population are exacerbated by noticeable environmental changes, which can increase the range of plant diseases, for instance, net blotch (NB), a foliar disease which significantly decreases barley (Hordeum vulgare L.) grain yield and quality. A resistant germplasm is usually identified through visual observation and the scoring of disease symptoms; however, this is subjective and time-consuming. Thus, automated, non-destructive, and low-cost disease-scoring approaches are highly relevant to barley breeding. This study presents a novel screening method for evaluating NB severity in barley. The proposed method uses an automated RGB imaging system, together with machine learning, to evaluate different symptoms and the severity of NB. The study was performed on three barley cultivars with distinct levels of resistance to NB (resistant, moderately resistant, and susceptible). The tested approach showed mean precision of 99% for various categories of NB severity (chlorotic, necrotic, and fungal lesions, along with leaf tip necrosis). The results demonstrate that the proposed method could be effective in assessing NB from barley leaves and specifying the level of NB severity; this type of information could be pivotal to precise selection for NB resistance in barley breeding.

Tunisian Silybum Species: Important Sources of Polyphenols, Organic Acids, Minerals, and Proteins across Various Plant Organs

Silybum marianum and Silybum eburneum are wild edible Mediterranean plants used in the human diet. This study presents the initial findings on the phytochemical characterization of Tunisian S. marianum and S. eburneum organs. It examined their mineral, sugar, organic acid, polyphenolic, and seed storage protein contents, as well as their antioxidant potential. In S. marianum, stems had high sodium and potassium contents, while the immature and mature seeds were rich in calcium and magnesium. However, S. eburneum had high potassium levels in stems and high sodium and calcium levels in the flowers. S. marianum showed substantial fructose variation among its organs. Conversely, S. eburneum exhibited significant heterogeneity in glucose, sucrose, and maltose levels across its organs, with maltose exclusively detected in the immature seeds. A notable organ-dependent distribution of organic acids was observed among the two species. Higher levels of phenolic contents were detected in both mature and immature seeds in both species compared to the other plant parts. The seeds possessed higher antioxidant activities than other plant organs. In both S. marianum and S. eburneum seeds, albumins and globulins were the predominant protein fractions. This study brings evidence supporting the important potential of Silybum organs as sources of nutrients with antioxidant properties for producing functional food.

Evaluation of the Content of Minerals, B-Group Vitamins, Tocols, and Carotenoids in Raw and In-House Cooked Wild Edible Plants

Notwithstanding the increased interest in wild edible plants, little is known on how some domestic thermal processes can affect their content. The aim of this study was to investigate the amounts of minerals, B1 and B2 vitamins, tocols, and carotenoids in raw, boiled, and steamed wild edible plants, namely, Sonchus asper (L.) Hill s.l., Sonchus oleraceus L., Cichorium intybus L., and Beta vulgaris L. var cicla. All vegetables were confirmed as high sources of lutein (from 6 to 9 mg/100 g) and β-carotene (from 2 to 5 mg/100 g). Quite high amounts of violaxanthin and neoxanthin were found. Alfa-tocopherol and γ-tocopherol were the main tocols, with same contents in raw and processed vegetables (about 2.5 mg/100 g). The most abundant macro element and trace element were, respectively, potassium and iron. B1 and B2 vitamins were found in low amounts in almost all plants, with the exception of thiamine in Beta vulgaris (about 1.6 mg/100 g). Boiling led to a significant loss of minerals (up to 60%) and B-group vitamins (up to 100%), while, among carotenoids, it only affected violaxanthin levels (up to 90%). Steamed vegetables showed only a slight reduction, about 20%, in β-carotene and lutein, with a marked decrease in violaxanthin and neoxanthin. One hundred grams of all fresh and cooked plants can be claimed as a source of vitamin A and E.

Chemical Composition of Wild Collected and Cultivated Edible Plants (Sonchus oleraceus L. and Sonchus tenerrimus L.)

The present work investigates the nutritional and bioactive composition, as well as the organoleptic and sensory properties, of S. oleraceus and S. tenerrimus, two wild plant species traditionally used in the gastronomy of the Mediterranean area. Additionally, the effect of cultivation on leaf composition was assessed to explore their potential for large-scale production and commercialization from the point of view of possible losses or gains in quality. Both species were characterized as a good source of bioactive compounds, such as vitamins, pro-vitamins and carotenoids, with health-promoting and antioxidant properties that are highly appreciated. The sensory profile revealed a good general acceptance of S. oleraceus and S. tenerrimus, indicating that they could be included in the diet. Although the cultivation of S. oleraceus resulted in a decrease in the concentration of phenolic compounds when compared to wild-harvested plants, the opposite occurred for vitamin C. In S. tenerrimus, cultivation also increased the concentration of other compounds with important nutritional and healthy properties, such as sugars, organic acids and β-carotene. The results of the composition, organoleptic and sensory properties of S. oleraceus and S. tenerrimus support the idea of their potential to be used as edible leafy vegetables and as promising assets for functional foods.

Nutritional Composition and Phytochemical Evaluation of Some Selected Wild Edible Plants in Tach Gaint District, Northwestern Ethiopia

The objective of the study was to evaluate the nutritional, mineral, and phytochemical analyses of some selected wild edible plants from Tach Gaint District, Northwest Ethiopia. Proximate composition parameters (moisture, ash, crude fibre, crude fat, crude protein, carbohydrate, and energy) were evaluated using the methods of the Association of Official Analytical Chemists, and elemental analysis was performed using the atomic absorption spectroscopy technique. Results from the nutritional analysis show that Erucastrum abyssinicum leaves had the highest crude protein content (17.47 ± 0.03 g/100 g), followed by Amaranthus graecizans (14.97 ± 0.03 g/100 g). The maximum moisture content (40.8 ± 0.00 g/100 g) and ash content (24.70 ± 0.15 g/100 g) were reported in the leaves of Amaranthus graecizans. The young shoots of Rumex abyssinicus had the highest crude fat content (14.07 ± 0.03 g/100 g) and the highest fibre content (34.70 ± 0.25 g/100 g), while the fruits of Opuntia ficus-indica had the highest amount of utilisable carbohydrate (44.4 ± 0.00 g/100 g) and the estimated energy value (326.4 ± 0.00 Kcal/100 g). Calcium was detected in considerable proportions (754.9 ± 0.23 mg/100 g) followed by iron (31.63 ± 0.03 mg/100 g) in Urtica simensis leaves and zinc content (3.09 ± 0.02 mg/100 g) in young shoots of Rumex abyssinicus. Qualitative phytochemical screening, alkaloids, phenols, flavonoids, triterpenes, saponins, and tannins were found in the methanolic extract of the plants. The results of this study suggest that the consumption of such nutrient-rich wild edible plants could help add a remarkable amount of nutrient and mineral in the human diet.