Biochemical characteristics and in vitro degradability of sunflower seed hull and wheat straw treated with Pleurotus ostreatus and Ganoderma sessile

BIDEGAIN, M.A.; POSTEMSKY PABLO; CELESTE LENTZ; CELIA RABOTNIKOF; ROBERTO DISTEL

Agriculture and Natural Resources

Kasetsart University

Lugar: Bangkok; Año: 2025 vol. 59 p. 1 - 10

Importance of the work: Exploring sustainable uses for regional agricultural residues canaddress the need for eco-friendly solutions in livestock feeding.Objectives: To evaluate the potential of Pleurotus ostreatus and Ganoderma sessile totransform sunflower seed hulls (SSH) and wheat straw and to enhance their in vitro digestibility.Materials and Methods: SSH and wheat straw were treated with Pleurotus ostreatus (strainsA01, PPWarm, P04, P0761, P07) and Ganoderma sessile strain E47. Colonization time, enzymeactivity, phenolic compounds content, reducing sugar content, fiber composition and in vitrodigestibility (IVD) were assessed, along with the impact of the inoculum formulation on thesevariables.Results: Fungal strains colonized substrates within 10–25 d. Laccase activity was in the ranges2,266–4,621 U/kg in SSH and 1,135–7,279 U/kg in wheat straw. Peroxidase activity was in therange 0–490 U/kg. In SSH, reducing sugars increased, with G. sessile E47 producing a 164%increase (p < 0.001). In contrast, in wheat straw, reducing sugars decreased, with P. ostreatus P04reducing the content by 64% (p < 0.001). The phenolic and triterpenoid contents decreased acrossall treatments. Fiber content changes were substrate-dependent—in the SSH, neutral detergentfiber and acid detergent fiber fractions, increased by 14.1–21.6%, while in the wheat straw, changeswere minimal. IVD remained unchanged for most treatments, except for P. ostreatus PPWarm(-20.7%, p = 0.013) and G. sessile E47 (-60.9%, p < 0.001) on SSH. Inoculum formulation withoutgrains altered mycelial effects on substrate degradation, increasing SSH digestibility by 70.5%(p = 0.003) after treatment with P. ostreatus A01.Main finding: The fungal treatments modified the SSH and wheat straw composition, withdigestibility improvement critically dependent on inoculum type and substrate.