Protein enrichment and digestibility of soft rush (Juncus effusus) and rice residues using edible mushrooms Pleurotus ostreatus and Pleurotus sajor-caju

Abstract

Pleurotus species are found to be among the most efficient lignocellulolytic types of white-rot fungi. Rice is the main grain cultivated in the extreme south of Brazil. Defatted rice bran and straw are by-products of low aggregate value. Soft rush (Juncus effusus) is a common native plant also very abundant in the region. In the present work, we evaluated changes in substrate composition after growth of two white-rot fungal species: Pleurotus ostreatus and Pleurotus sajor-caju, aiming to increase protein content and digestibility from substrates through solid fermentations and obtain edible mushrooms of high aggregate value. For that, defatted rice bran, defatted rice straw and soft rush were utilized as substrate. The influence of the variables thermal treatment temperature of substrate, substrate moisture and concentration were evaluated on the protein content, digestibility and biological efficiency. The highest protein enrichment of rice bran in P. sajor-cajufermented medium was due the fact that there was no fructification in these media, while for the P. ostreatusfermented medium, part of the synthesized protein was converted into mushrooms. The highest protein enrichments were verified in medium with 80% moisture and 25% soft rush (47.1% using P. ostreatus and 49.0% using P. sajor-caju). A higher digestible protein increase was obtained for both species in media with 70% moisture and 25% soft rush.

Agronomic Qualitative Viability of Spent Pleurotus Substrate and its Mixture with Wheat Bran and a Commercial Supplement

“…Fonseca et al . (), using a mixture of rice straw (35%), Juncus effusus L. (25%) and rice bran (40%) achieved an ash content of 6.38% by growing P. ostreatus and other Pleurotus species, such as P. eryngii , Manzi et al . (), in substrates based on WS + sugar beets (15%), reached ash content values between 6.90% and 10.50%.…”

“…Siwulski et al (2009) cultivating oyster mushroom sawdust supplemented with alder leaves of Ginkgo biloba L. conclude that the addition of Ginkgo biloba L. leaves does not affect the ash content of fruiting bodies: green leaves, between 6.90% (without addition to the cultivation substrate of G. biloba leaves and containing 10% leaves) and 7.00% (containing 1% leaves); and yellow leaves, from 6.80% (without addition of G. biloba leaves) and 7.20% (with a 10% content leaves). Fonseca et al (2009), using a mixture of rice straw (35%), Juncus effusus L. (25%) and rice bran (40%) achieved an ash content of 6.38% by growing P. ostreatus and other Pleurotus species, such as P. eryngii, Manzi et al (2004), in substrates based on WS 1 sugar beets (15%), reached ash content values between 6.90% and 10.50%. Also with P. eryngii, Hassan et al (2010) presented similar values to those achieved in the present experiment: sawdust (6.94%), soybean straw (7.66%), sugarcane bagasse (6.54%) and rice straw (8.02%).…”

Upgrading the Nutritional Value of Rice Bran by Solid-State Fermentation with Pleurotus sapidus

“…Pleurotus species are edible fungi that belong to the basidiomycota division; they can be grown in a wide variety of plant-based substrates [2,3,10]. This work focuses on the fermentation of rice bran by P. sapidus, which is a well-known edible fungus that is easy to cultivate in SSF, provides high nutritional quality food, and produces fascinating enzymes and metabolites [3,[10][11][12].…”

Biotransformation of Pequi and Guavira Fruit Wastes via Solid State Bioprocess Using Pleurotus Sajor-Caju

“…These lipids are destined for construction of the mushroom cell wall and for income induction. With growth, the lipids were excreted and maintained in the medium, raising its percentage [12]. As there was no fructification, lipids start to be consumed when cell growth reach or approximate to the stationary phase, as observed in Fig.…”

“…Pleurotus ssp. mycelium can grow on lignocellulosic wastes mainly because it is able to produce cellulolytic and ligninolytic enzymes which allow them to degrade complex carbohydrates, increasing fiber content [12]. The concentration of minerals could be correlated with other mechanisms, such as nitrogen fixation [25].…”