In the last decade, there has been an increase in the use of sprouted grains in human diet and a parallel increase in the scientific literature dealing with their nutritional traits and phytochemical contents. This review examines the physiological and biochemical changes during the germination process, and the effects on final sprout composition in terms of macro- and micro-nutrients and bioactive compounds. The main factors affecting sprout composition are taken into consideration: genotype, environmental conditions experimented by the mother plant, germination conditions. In particular, the review deepens the recent knowledge on the possible elicitation factors useful for increasing the phytochemical contents. Microbiological risks and post-harvest technologies are also evaluated, and a brief summary is given of some important in vivo studies matching with the use of grain sprouts in the diet. All the species belonging to Poaceae (Gramineae) family as well as pseudocereals species are included.
17 March 2020 in Journal of Agricultural and Food Chemistry
Selenium (Se) is an important micronutrient for living organisms, since it is involved in several physiological and metabolic processes. Se intake in humans is often low, very seldom excessive, and its bioavailability depends also on its chemical form, with organic Se as the most available after ingestion. The main dietary source of Se for humans is represented by plants, since many species are able to metabolize and accumulate organic Se in edible parts to be consumed directly (leaves, flowers, fruits, seeds and sprouts) or after processing (oil, wine, etc.). Countless studies have recently investigated on Se biofortification of plants to produce Se enriched foods and elicit the production of secondary metabolites which may benefit human health when assumed with the diet. Moreover, feeding animals Se-rich diets may provide Se-enriched meat. This work reviews the most recent literature on nutraceutical profile of Se enriched foods from plant and animal sources.
Sprouts and microgreens have attracted tremendous interest across multiple disciplines in recent years. Here, we critically review the most recent advances to underscore research prospects and niches, and related challenges, not yet addressed or fully pursued. In particular, we report a number of themes that merit special attention as a result of their relevance to plant science, nutrition, health, and zootechnics: (1) species not yet or inadequately investigated, such as wild plants, and fruit tree strains; (2) abiotic and biotic factors, and biostimulants, for elicitation strategies and metabolic engineering; (3) sanitization and processing technologies to obtain high-quality products; (4) digestive fate and impact of bioactive elements, antinutrients, and allergens on human nutrition; (5) experimental challenges to researching health benefits; (6) the opportunity to generate natural product libraries for drug discovery; and (7) sprouts in animal feeding to improve both animal health and the nutritional value of animal products for the human diet. The convergence of different themes involving interdisciplinary competencies advocate fascinating research pursuits, for example, the elicitation of metabolic variants to generate natural product collections for identification and selection of bioactive chemicals with a role as nutraceuticals, key constituents of functional foods, or interactive partners of specific drugs.
The use of sprouts in the human diet is becoming more and more widespread because they are tasty and high in bioactive compounds and antioxidants, with related health benefits. In this work, we sprouted rapeseed under increasing salinity to investigate the effect on free and bound total phenolics (TP), non-flavonoids (NF), tannins (TAN), phenolic acids (PAs), and antioxidant activity. Seeds were incubated at 0, 25, 50, 100, 200 mM NaCl until early or late sprout stage, i.e., before or after cotyledon expansion, respectively. Sprouting and increasing salinity slightly decreased the bound fractions of TP, NF, TAN, PAs, while it increased markedly the free ones and their antioxidant activity. Further increases were observed in late sprouts. Moderate salinity (25–50 mM NaCl) caused the highest relative increase in phenolic concentration while it slightly affected sprout growth. On the contrary, at higher NaCl concentrations, sprouts grew slowly (100 mM NaCl) or even died before reaching the late sprout stage (200 mM). Overall, moderate salinity was the best compromise to increase phenolic content of rapeseed sprouts. The technique may be evaluated for transfer to other species as a cheap and feasible way to increase the nutritional value of sprouts.
5 August 2020 in Journal of Agricultural and Food Chemistry
This work aimed to study the effect of some light spectra on the growth, oxidative state, and stress of einkorn wheatgrass (Triticum monococcum L. ssp. monococcum). To this end, six light treatments, having the same total incident photon flux density (PFD) of 200 μmol m–2 s–1, were applied to einkorn and compared: only blue light; only red; three blue:red combinations, at different proportions of total PFD (75:25%, 50:50%, and 25:75%, respectively); and a wide spectrum, taken as a control treatment, composed of blue (18% of PFD), red (18%), and intermediate wavelengths (64%). Light treatments affected the contents of pigments (chlorophylls and carotenes), hydrogen peroxide (H2O2), and malondialdehyde (MDA). These results revealed the changes in the oxidative status of wheatgrass, in response to the different light treatments. However, the dichromatic light with blue ≥50% of the total PFD appeared to be the best combination, guarantying good wheatgrass yield, increasing pigment content, and reducing H2O2 and MDA when compared to the other light treatments. Our findings also contribute to explaining the available literature on the effect of these kinds of light on the increase in phenolic compounds and antioxidant activity in einkorn wheatgrass.
The evaluation of potential biostimulants to be used in sustainable horticulture production is a crucial goal of research. Most research has focused on the effects of biostimulants on plant growth, and less on the effects on seed germination and seedling growth. This study evaluated the biostimulatory effects of mugwort extract on seed germination and seedling growth in several vegetable crops (onion, carrot, tomato, rapeseed, cauliflower and lettuce), in order to test its application as a potential biostimulant. The phenolic acid composition of the extract and the acids’ rankings were: homovanillic > gentisic > gallic > caffeic = chlorogenic > salicylic = syringic > p/m-coumaric = ferulic = synaptic = p-hydroxybenzoic. The extract of mugwort (at 0.2, 0.4, 0.8, 1.56, 3.13, 6.25 and 12.5 % w/v concentrations) was analyzed using Petri dish bioassays, quantifying its stimulatory effects on seed germination and the radicle and hypocotyl length of the seedlings, according to hormetic log-logistic models. The mugwort extract was not able to biostimulate all the tested species. Seed germination was stimulated in carrot (+70%) and rapeseed (+11%), while in the other species, no effects (i.e., onion, tomato and lettuce) or inhibition (i.e., cauliflower) were observed. Hypocotyl length stimulation was observed in all the species except carrot and onion, while radicle length was mainly inhibited by mugwort extract, except in rapeseed (+30%). The biostimulation effects of mugwort extract seem to be “specie specific” and “part of plant specific”, and need to be further investigated in terms of the involved substances and physiological aspects, although phytohormone activity is certainly involved.