Phenolic compounds represent a group of secondary metabolites that serve essential functions in plants. Beyond their positive impact on plants, these phenolic metabolites, often referred to as polyphenols, possess a range of biological properties that can promote skin health. Scientific research indicates that topically using phenolics derived from plants can be advantageous, but their activity and stability highly depend on storage of the source material and the extraction method. These compounds have the ability to relieve symptoms and hinder the progression of different skin diseases. Because they come from natural sources and have minimal toxicity, phenolic compounds show potential in addressing the causes and effects of skin aging, skin diseases, and various types of skin damage, such as wounds and burns. Hence, this review provides extensive information on the particular crops from which by-product phenolic compounds can be sourced, also emphasizing the need to conduct research according to proper plant material storage practices and the choice of the best extracting method, along with an examination of their specific functions and the mechanisms by which they act to protect skin.

Phenolic compounds represent a group of secondary metabolites that serve essential functions in plants. Beyond their positive impact on plant, these phenolic metabolites, often referred to as polyphenols, possess a range of biological properties that can promote skin health. Scientific research indicates that using phenolics derived from plants topically can be advantageous, but the activity and stability highly depend on storage of the source material and the extract method. These compounds have the ability to relieve symptoms and hinder the progression of different skin diseases. Because they come from natural sources and have minimal toxicity, phenolic compounds show potential in addressing the causes and effects of skin aging, skin diseases, and various types of skin damage, such as wounds and burns. Hence, this review provides an extensive information of the particular crops from which by-product phenolic compounds can be sourced, but pointing the need investigation according to a proper storage plant material and the choice of the best extracting method, along with an examination of their specific functions and the mechanisms by which they act to protect skin.

The use of plant-based biostimulants is a sustainable strategy to enhance crop growth while mitigating the environmental impact of synthetic agrochemicals. Broccoli by-products, rich in bioactive compounds, have emerged as a promising resource, though their composition is influenced by plant growing conditions. This study investigates the biostimulant potential of broccoli-derived extracts obtained from leaves, stems, and petioles of plants cultivated in three different seasons (autumn, winter, and spring) and their effect on the germination and early growth of pak choi (Brassica rapa subs. chinensis L.) seeds. A comprehensive biochemical characterization, including mineral content, glucosinolates, and phenolic compounds, was conducted to explore how seasonal and tissue-specific variations impact their composition and biostimulant efficacy. Principal Component Analysis (PCA) revealed distinct metabolic profiles across seasons and plant tissues, with leaf-derived extracts showing higher correlations with phenolic acids and trace minerals, whereas petiole and stem extracts were associated with macronutrients. Germination assays demonstrated that extracts from autumn and winter exhibited the highest biostimulant activity, likely due to their enriched secondary metabolite profiles and well-balanced mineral composition. In contrast, spring extracts, despite their higher macronutrient content, showed limited biostimulant effects, possibly due to physiological constraints in broccoli plants during spring, when they experience reduced bioactive potential. PCA and correlation analysis identified metabolites, particularly sinapic acid and glucobrassicin, as key contributors to enhanced seedling development. Furthermore, a positive relationship between sulfur content and glucosinolate levels suggests that sulfur concentration could serve as a useful quality marker for assessing the bioactivity of broccoli-based biostimulants. This study underscores the potential of broccoli-derived extracts as sustainable biostimulants for improving germination and seedling development in pak choi. The findings highlight the influence of seasons on the bioactive composition of extracts, with low temperatures and high relative humidity favoring the accumulation of secondary metabolites and an optimal nutrient balance in plants.

Membrane vesicles isolated from vegetable tissues have shown promise in encapsulation technologies used in industries like food and cosmetics, offering innovative approaches to product development. However, their associated linked metabolites have not been studied. Lemon vesicle research not only adds value to the lemon crop (Citrus × limon L.), one of the most widely cultivated fruit trees in the world, is a source of bioactive compounds such as phenolics and organic acids. In this study, the influence of elicitation with ZnSO₄ and methyl jasmonate, which modulate the bioactive metabolites, on fruit membrane vesicle bond metabolites was studied. The study showed that foliar application of ZnSO₄ increased phenolic compounds as caffeic, sinapic, and chlorogenic acids and the flavonoid hesperidin by about 20% in lemons. Furthermore, a clear interaction between vesicles and citrate and ascorbate that were increased by methyl jasmonate were associated with their higher bioactivity. This was related to the double intrinsic in vitro antioxidant activities of these vesicles.

Plant-derived nanovesicles represent a promising tool for enhancing nutrient and bioactive compound delivery in agriculture. Lemon-pulp-derived vesicles were characterized in terms of mineral and bioactive content, revealing stable compartmentalization of both macro- and micronutrients alongside flavonoids such as hesperidin. Foliar application of these vesicles on spinach culture promoted plant growth, with Zn encapsulation further enhancing biomass accumulation compared to free Zn. This suggested an improvement of nutrient transport and bioavailability. Vesicle treatments modulated spinach secondary metabolism, delivering intrinsic flavonoids to recipient tissues and inducing the accumulation of phenolic compounds not naturally present. Hormonal profiling indicated targeted effects on SA, IAA and ABA levels, while mineral analyses confirmed no adverse impact on nutrient uptake. These findings demonstrate that lemon-derived nanovesicles function as dual biostimulants and nutrient carriers, offering a novel strategy for improving crop performance, nutritional value, and bioactive enrichment.