Sorghum is a gluten-free cereal representing a staple food in many countries of Africa, where germination is traditionally used for the preparation of several sorghum-based products. This study focused on the effect of germination on total phenolic content, in vitro and ex vivo antioxidant activity, and antihypertensive action of sorghum from Togo. Total phenolic content was estimated as Folin–Ciocalteu reducing capacity, while antioxidant activities were assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric Reducing Antioxidant Power (FRAP) in vitro tests and ex vivo by the cellular antioxidant activity (CAA) assay on human erythrocytes. The antihypertensive effect of germinated and non-germinated sorghum peptides fraction was evaluated as angiotensin-converting enzyme (ACE) inhibitory activity. Despite our findings demonstrated no impact of germination on the total phenolic content, non-germinated sorghum showed significantly higher in vitro antioxidant activities than the germinated one; further, non-germinated sorghum displayed significantly higher ACE inhibition than germinated sorghum that, instead, at lower doses, exhibited better erythrocytes protection from peroxyl radicals. In conclusion, the germination process negatively impacted the in vitro antioxidant activity and the antihypertensive effect of sorghum while improved erythrocytes protection. This study evidenced better nutraceutical potential of non-germinated sorghum that, besides good antioxidant activity, represents an important source of ACE-inhibitory peptides. However, the germination process might have positively impacted the profile of bioactive compounds involved in the protection of human erythrocytes from oxidative damage.

The fermentation process has been widely used to improve plant-based foods’ nutritional and nutraceutical properties. This study aimed to investigate and compare the impact of sourdough fermentation on the bioactive content and profile, antioxidant and antihypertensive activities, as well as the anti-inflammatory properties of fermented (FS) and non-fermented (NFS) flour from Tuscan Triticum dicoccum wheat (spelt) on tumor necrosis factor-alpha (TNF-α)-inflamed human intestinal epithelial cells (HT-29). FS showed significantly higher total phenolic and flavonoid content, in vitro and ex vivo antioxidant activities, and ACE-inhibitory activities than NFS. Gallic acid was identified by HPLC-DAD as the most representative polyphenol, followed by rutin, trans-ferulic acid, iso-quercitrin, and quercetin, in the fermented spelt sample. Instead, rutin and gallic acid were identified as the predominant compounds in the non-fermented ones. Moreover, FS exhibited a better protective effect on inflamed HT-29 cells by significantly counteracting the TNFα-induced alterations, lowering the expression of IL-8, COX-2, and ICAM-1 inflammatory mediator while enhancing antioxidant enzyme HO-1 gene expression. In conclusion, sourdough fermentation positively affected the nutraceutical and functional properties of spelt, which may represent a valuable ingredient for the formulation of functional foods and a key product for managing hypertension and inflammatory intestinal diseases.

Cereals are rich in nutrients and bioactive compounds; however, many of these, such as polyphenols, are bound to the cell wall matrix, limiting their bioavailability. This study investigated the use of fermentation to enhance the bioavailability of functional compounds in whole-wheat flour. Given the impact of microbial species on fermentation outcomes, various combinations of lactic acid bacteria and yeast strains were examined. The polyphenol and flavonoid content of different fermented flours was analyzed. Additionally, the antioxidant capacity was assessed using in vitro assays (DPPH, ORAC, and FRAP) and an ex vivo test with human erythrocytes. Fermentation significantly enhanced the release of bioavailable phenolic compounds and flavonoids, with the most significant increases reaching up to 3.4-fold and 2.64-fold, respectively. In particular, the findings highlight the capacity of flour fermented with a combination of K. humilis, F. sanfranciscensis, E. faecium, P. pentosaceus, and L. mesenteroides to enhance antioxidant activity in vitro and to protect human red blood cells from oxidative stress. Furthermore, fermentation increased the production of short-chain fatty acids, notably lactate and acetate, which are widely recognized for their gut health benefits. Overall, this study highlights the effectiveness of targeted fermentation in improving the bioactivity and antioxidant properties of whole-wheat flour.

Millet, a gluten-free cereal, has received attention for its environmental friendliness and higher protein content than other grains. It represents a staple food in many African countries, where fermentation is traditionally used for preserving food products and preparing different cereal-based products. This study aimed to assess the impact of sourdough fermentation on bioactive compounds and antioxidant and anti-inflammatory properties of pearl millet from Burkina Faso. Phenolic compounds were investigated spectrophotometrically and by HPLC-DAD. The antioxidant activity of unfermented (MF) and fermented (FeMF) millet was evaluated in vitro by spectrophotometric and fluorometric assays and ex vivo on oxidized human erythrocytes for hemolysis inhibition. Finally, the potential anti-inflammatory effect of FeMF and MF was evaluated on human adenocarcinoma cell line (HT-29) exposed to TNF-α inflammatory stimulus. Results revealed significantly higher levels of polyphenols, flavonoids, and in vitro antioxidant activity following millet fermentation. Notable differences in phenolic composition between FeMF and MF are observed, with fermentation facilitating the release of bioactive compounds such as gallic acid, quercetin, and rutin. A dose-dependent protection against oxidative hemolysis was observed in both FeMF- and MF-pretreated erythrocytes. Similarly, pretreatment with FeMF significantly reduced the levels of inflammatory markers in TNF-α-treated cells, with effects comparable to those of MF. Fermentation with sourdough represents a simple and low-cost method to improve the bioactive compounds content and in vitro antioxidant activity of millet flour with promising nutraceutical potential.

Higher plants will play a key role in human survival in Space, being able to regenerate resources and produce fresh food. However, the creation of a fertile substrate based on extra-terrestrial soils is still a challenge for space cultivation. We evaluated the adaptability of soybean (Glycine max (L.) Merr.) cultivar ‘Pr91M10′ to three substrates, the Mojave Mars regolith Simulant MMS-1, alone (R100), and in a mixture with blond sphagnum peat at two different volumes, 85:15 (R85P15) and 70:30 (R70P30), in plants directly sown on the substrates or transplanted after sowing on peat. The low pH of peat (4.34) allowed the mitigation of the alkalinity of the Mars regolith simulant (pH 8.86), lowering the initial pH to neutral (6.98, R85P15), or subacid to neutral (6.33, R70P30) values. Seed germination reached the highest percentage in the shortest time in the mixture of regolith simulant with 15% of peat. The cultivation substrate did not affect the plant growth and nutritional status. However, a significant interaction between the substrate and planting method was found in several growth parameters, with the highest positive effects observed in plants resulting from direct sowing on the regolith mixture with peat.