Increasing Antioxidant Activity and Protein Digestibility in Phaseolus vulgaris and Avena sativa by Fermentation with the Pleurotus ostreatus Fungus

Abstract

The aim of the research was to determine the impact of fermentation with Pleurotus ostreatus on kidney beans, black beans, and oats. The results indicate that the fungus has a positive effect on the substrates when compared to the controls. The antioxidant activity (39.5% on kidney beans and 225% on oats in relation to the controls) and content of total polyphenols (kidney beans three times higher regarding the controls) increased significantly by the presence of the fungus mycelium, even after simulated digestion. There was a significant increase in protein digestibility (from 39.99 to 48.13% in black beans, 44.06 to 69.01% in kidney beans, and 63.25 to 70.01% in oats) and a decrease of antinutrient tannins (from 65.21 to 22.07 mg in black beans, 35.54 to 23.37 in kidney beans, and 55.67 to 28.11 in oats) as well as an increase in the contents of some essential amino acids. Overall, this fermentation treatment with Pleurotus ostreatus improved the nutritional quality of cereals and legumes, making them potential ingredients for the elaboration and/or fortification of foods for human nutrition.

Biotransformation of rice and sunflower side-streams by dikaryotic and monokaryotic strains of Pleurotus sapidus: Impact on phenolic profiles and bioactive properties

“…In contrast to P. sapidus fermentation, the extraction of phenolic compounds was improved by SSF of wheat using the edible fungus Rhizopus oryzae RCK2012, and the extracts possessed higher antioxidant activity in vitro (ABTS and DPPH methods) as well as in vivo (Saccharomyces cerevisiae method) in comparison with the activity displayed by the substrate (Bhanja Dey & Kuhad, 2014). Similar results were reported for the extracts obtained after SSF of agro-industrial side-streams using different white rot fungal species, such as P. ostreatus, P. chrysosporium or P. floridensis (Espinosa-Páez et al, 2017;Sharma & Arora, 2014). The extraction of phenolic compounds through fermentation processes was demonstrated to be an efficient bioprocess in comparison with the extraction with organic solvents.…”

“…Since phenolic compounds consist of several chemical subgroups such as phenylpropanoids, flavonoids and polymers such as tannins, the modifications produced by SSF might derivate in a more bioactive blend (Bhanja Dey & Kuhad, 2014). Previous studies pointed out that different white rot fungi species such as Phanerochaete chrysosporium, Phlebia floridensis, Lentinula edodes, or Pleurotus ostreatus showed a positive enhancement of the total phenolic content, sterols, protein digestibility and antioxidant activities after 15 to 60 days of SSF, using wheat straw, paddy straw, seeds of fresh black beans and oat, as substrates (Espinosa-Páez et al, 2017;Sharma & Arora, 2014;Wang et al, 2018). However, that was not the case for the phenolic fractions recovered after the SSF of rice and sunflower side-streams by P. sapidus strains (Mk and Dk).…”

“…Results indicated that P. sapidus could present an interesting biocatalyst for the SSF of other agro-industrial sidestreams with high polyphenolic and anti-nutritional compounds content (Torres-León et al, 2018). Previous reports indicated that the process was efficient to recover other value-added products with high demand in the food industry such as enzymes, sterols, and protein rich material (Espinosa-Páez et al, 2017;Martins et al, 2011;Postemsky et al, 2019;Sharma & Arora, 2014;Wang et al, 2018).…”

“…Their products could thus be directly introduced in food, pharmaceutical, cosmetic or other applications (Ghorai et al, 2009). Amongst the different cultivated species, genus Pleurotus is a suitable choice considering that is the second most cultivated and consumed mushroom in the world (Espinosa-Páez et al, 2017). In particular, P. sapidus is easy to cultivate in solid and liquid fermentation, it has a short life cycle and it has demonstrated its potential for metabolite production and compound bioconversion.…”

Harnessing Microbes for Sustainable Development: Food Fermentation as a Tool for Improving the Nutritional Quality of Alternative Protein Sources

“…However, the scientific literature on the effects of cereal food fermentation on the oat protein digestibility and amino acid availability is rather scarce. In one study, the protein digestibility of oat grain was improved by fermentation with oyster mushroom Pleurotus ostreatus CS155 strain (2 weeks at room temperature), along with an increase in soluble nitrogen and a reduction in tannin content [119]. In addition, tempeh-type oat fermentation with filamentous fungi (Aspergillus oryzae var.…”