Marine algae are renowned for their health benefits due to the presence of functional bioactive compounds. In this context, this study aims to valorize the extract of a seaweed, Dictyota dichotoma (D. dichotoma), through phytochemical characterization using liquid chromatography–mass spectrometry (HPLC-MS), as well as in vitro and in silico evaluation of its biological activities (antioxidant and antimicrobial). Phytochemical characterization revealed that the ethanolic extract of Dictyota dichotoma (DdEx) is rich in phenolic compounds, with a total of 22 phycocompounds identified. Antioxidant activity, measured by various methods, showed an IC₅₀ of 120 µg/mL for the DPPH assay, an EC₅₀ of 120.53 µg/mL for the FRAP assay, and a total antioxidant power of 685.26 µg AAE/mg according to the phosphomolybdate (TAC) method. Evaluation of antibacterial activity showed a zone of inhibition diameter ranging from 11.93 to 22.58 mm, with the largest zone observed for the Escherichia coli (E. coli) strain. For antifungal activity, inhibition zone diameters ranged from 22.38 to 23.52 mm, with the largest recorded for the Saccharomyces cerevisiae (S. cerevisiae) strain. The in silico study identified tetragalloyl-glucose, apigenin-7-O-glucoside, and pentagalloyl-glucose as the most active compounds against NADPH oxidase, with docking scores of −7.723, −7.424, and −6.402 kcal/mol, respectively. Regarding antibacterial activity, apigenin-7-O-glucoside, pelargonidin-3-O-glucoside, and secoisolariciresinol demonstrated high affinity for E. coli beta-ketoacyl-[acyl carrier protein] synthase, with docking scores of −7.276, −6.811, and −6.594 kcal/mol, respectively. These in vitro and in silico evaluations showed that D. dichotoma extract possesses antioxidant and antimicrobial properties, due to its richness in bioactive compounds identified by HPLC.

Phytogenics are functional compounds with a growing interest in animal nutrition. These plant-derived compounds are often used to improve health and behavioral aspects in livestock, and used as antipathogenic agents. Melatonin, an indolic hormonal compound, has been studied as an interesting phytogenic in animal nutrition. This study analyzes the possibilities of acorn-fed flour as a phytomelatonin contributor and its beneficial roles for health. The fruits of two varieties of acorns (Quercus suber var. Maamora and var. Bouhachem), recollected in two different regions of Morocco, have been studied according to their eco-physiological origin. The content in phytomelatonin was analyzed using a solid extractive method and determined by liquid chromatography with fluorescence detection. The results show great morphological differences between the two varieties, and also significant differences in their phytomelatonin content. It is concluded that acorn-fed flour can be an interesting raw material as a phytomelatonin contributor for the functionality of certain feeds and animals. More specific studies using phytomelatonin-rich plants as feed have been proposed to implement specific functionalities in livestock.

Phytomelatonin is a versatile compound with important roles in plants, spanning from promoting germination and plant growth to defending against abiotic and biotic stresses. Its natural origin as biostimulator aligns with sustainable agricultural practices that aim to reduce reliance on synthetic agrochemicals while supporting crop productivity. As research progresses and reveals its full potential across various sectors of agriculture and food production systems, phytomelatonin emerges as a promising candidate for integrated crop management, with the goal of achieving more resilient and sustainable food systems worldwide. More agronomic data will be essential to decide whether the use of (phyto)melatonin can be a clear advance in the improvement of crops and their production. This paper presents the possible improvements and challenges to be faced in order to elucidate whether the cost/benefit balance in the use of melatonin in crops will be environmentally and economically sustainable.

Microgreens are usually grown on non-edible substrates, whereas edible substrates enable a fully edible, ready-to-eat product. This study evaluated mustard (white, red and green) microgreens grown on an edible gellan gum substrate within a “farm on the fork” system. Agronomical parameters (dry weight, germination, cotyledon area) and bioactive properties (phenolics, antioxidant capacity, phytomelatonin) were assessed during germination. Essential oil supplementation was also evaluated for sensory and antifungal purposes. Gellan gum at 20 g/L was optimal, supporting high germination (red: 95.7%, green: 98.3%, white: 100% at 72 h) and growth without irrigation. After 9 days, white mustard showed the highest fresh weight (63.1 mg/seedling), hypocotyl length (3.52 cm) and cotyledon area (43.5 mm²), while red mustard had the greatest nutraceutical value, with the highest carotenoids (76.4 µg/g FW), flavonoids (4.56 mg/g FW), antioxidant capacity (9.02 µmol TE/g FW) and phytomelatonin (25.5 ng/g FW). Essential oils did not affect biometric traits or antioxidant profile at harvest, although transient rises in flavonoids (+0.34 mg/g FW), antioxidant capacity (+0.97 µmol TE/g FW) and phytomelatonin (two-fold) occurred at early stages (day 3–6). Overall, gellan gum—alone or with essential oils—enabled safe, effective production of ready-to-eat mustard microgreens without compromising growth or nutritional quality.