Pretreatment of Grape Stalks by Fungi: Effect on Bioactive Compounds, Fiber Composition, Saccharification Kinetics and Monosaccharides Ratio.

Grape stalks, an inedible lignocellulosic residue from winemaking and agro-industrial grape juice production, can be valorized as a source of bioactive compounds and as feedstock for the saccharification and bioconversion of soluble sugars. Solid-state fermentation (SSF) by six white-rot fungi was applied as pretreatment. Fiber composition, free radical scavenging activity, four ligninolytic, and three hydrolytic enzyme activities were determined.

In vitro adsorption of aflatoxin B, ochratoxin A, and zearalenone by micronized grape stems and olive pomace in buffer solutions.

This work characterizes the adsorption of aflatoxin B (AFB), ochratoxin A (OTA), and zearalenone (ZEN) by dry micronized olive pomace (OliPom) and grape stems (GrapStem). Their performance was compared with that of three other materials, activated carbon (ActCarb), bentonite (Bent), and a commercial product (ComProd). Experiments were conducted in vitro at several pH values using buffer solutions.

Evaluation of the nutritive value of muiumba (Baikiaea plurijuga) seeds: chemical composition, in vitro organic matter digestibility and in vitro gas production.

One of the main constraints hindering the increase of animal production in semi-arid regions of Africa is the inadequate supply of nutrients during the dry season. Incorporation of alternative feed resources in ruminant diets during this period could be a viable approach to overcome these limitations. The objective of this study was to evaluate the nutritive value of muiumba (Baikiaea plurijuga) tree seeds as an alternative nutrient source for ruminants.

Influence of ligninolytic enzymes on straw saccharification during fungal pretreatment.

Solid state and submerged fermentations in the presence of white-rot basidiomycetes (Bjerkandera adusta, Fomes fomentarius, Ganoderma resinaceum, Irpex lacteus, Phanerochaete chrysosporium, Trametes versicolor and basidiomycete Euc-1) and the litter-decomposing basidiomycete Lepista nuda were evaluated as a pretreatment to increase enzymatic saccharification of wheat straw. Enzymatic hydrolysis of holocellulose after solid state pretreatment showed a significant (P<0.05) increase of saccharification process for T.

Enzymatic saccharification of biologically pre-treated wheat straw with white-rot fungi.

Wheat straw was submitted to a pre-treatment by the basidiomycetous fungi Euc-1 and Irpex lacteus, aiming to improve the accessibility of cellulose towards enzymatic hydrolysis via previous selective bio-delignification. This allowed the increase of substrate saccharification nearly four and three times while applying the basidiomycetes Euc-1 and I. lacteus, respectively.

Modification of wheat straw lignin by solid state fermentation with white-rot fungi.

The potential of crude enzyme extracts, obtained from solid state cultivation of four white-rot fungi (Trametes versicolor, Bjerkandera adusta, Ganoderma applanatum and Phlebia rufa), was exploited to modify wheat straw cell wall. At different fermentation times, manganese-dependent peroxidase (MnP), lignin peroxidase (LiP), laccase, carboxymethylcellulase (CMCase), avicelase, xylanase and feruloyl esterase activities were screened and the content of lignin as well as hydroxycinnamic acids in fermented straw were determined. All fungi secreted feruloyl esterase while LiP was only detected in crude extracts from B.