The impact of boiling and in vitro human digestion of Solanum nigrum complex (Black nightshade) on phenolic compounds bioactivity and bioaccessibility.

Solanum nigrum complex (Black nightshade) is a wild leafy vegetable with phenolic antioxidant compounds related to the reduction of oxidative stress. Changes in phenolics and bioactivity due to cooking and gastrointestinal digestion of black nightshade were compared to spinach. Predominant compounds of black nightshade were myricetin, quercetin-3-O-robinoside, 3,4-dicaffeoylquinic acid, 3-caffeoylquinic acid, and rutin, which were improved after boiling but reduced after in vitro digestion. Phenolics were reduced after digestion of black nightshade and spinach; however, bioactivity was still retained, especially in preventing oxidative stress in Caco-2 cells. Hence, indicating their potential to reduce oxidative stress related diseases of the digestive tract.

Influence of boiling and subsequent phases of digestion on the phenolic content, bioaccessibility, and bioactivity of Bidens pilosa (Blackjack) leafy vegetable.

The effects of boiling and in vitro human simulated digestion on phenolic compounds and bioactivity of the African leafy green vegetable, Bidens pilosa, known as Blackjack in South Africa, was investigated and compared to the leafy green vegetable Spinacia oleracea (Spinach). Metabolites such as 3-caffeoylquinic acid, catechin, 4-caffeoylquinic acid, quercetin-3-O-robinobioside, rutin and quercetin-3-O-glucoside were dominant in the boiled methanolic compared with the raw methanolic extracts of the Blackjack. The total phenolic and flavonoid content generally decreased after in vitro complete digestion for both raw and boiled extracts, indicating that pH and environment associated with digestion alters the bioactivity of the extracted phenolics. Both leafy green vegetables had beneficial effects, but all Blackjack extracts were more effective in preventing the AAPH-mediated oxidation of Caco-2 cells, low-density lipoprotein and deoxyribonucleic acid than those of the spinach. This study identified the health benefits of eating Blackjack and therefore, the cultivation and consumption of this leafy green vegetable should be promoted.

Fermented and malted millet products in Africa: Expedition from traditional/ethnic foods to industrial value-added products.

With the prevalent food insecurity in Africa, there is a growing need to utilize the available crops to develop nutritious, affordable and palatable food for the populace. Millet is critical in this role, relative to its abundance in the continent and good nutritional composition. For ages, fermentation and malting have been traditionally used to transform millet into variety of produce. A paradigm shift has however occurred over the years, giving birth to new commercially available products. This review thus appraises and gives an overview of traditional and modern fermented and malted products. Although, millet has been diversified to several products, its major food uses are still restrained to traditional consumers and largely remains underutilized. Considering the potential embedded in this grain, it is important to explore this crop through the application of appropriate modern fermentation and malting technologies. This will ensure the availability of ready to eat (RTE) and ready to use (RTU) food products and to a large extent address the incessant food security challenges plaguing Africa.