Production of lignocellulolytic enzymes and enhancement of in vitro digestibility during solid state fermentation of wheat straw by Phlebia floridensis

AbstractBrewer’s spent grain (BSG) is the largest by-product originated from the brewery industry with a high potential for producing carbohydrases by solid-state fermentation. This work aimed to test the efficacy of a carbohydrases-rich extract produced from solid-state fermentation of BSG, to enhance the digestibility of a plant-based diet for European seabass (Dicentrarchus labrax). First, BSG was fermented with A. ibericus to obtain an aqueous lyophilized extract (SSF-BSG extract) and incorporated in a plant-based diet at increasing levels (0—control; 0.1%, 0.2%, and 0.4%). Another diet incorporating a commercial carbohydrases-complex (0.04%; Natugrain; BASF) was formulated. Then, all diets were tested in in vitro and in vivo digestibility assays. In vitro assays, simulating stomach and intestine digestion in European seabass, assessed dietary phosphorus, phytate phosphorus, carbohydrates, and protein hydrolysis, as well as interactive effects between fish enzymes and dietary SSF-BSG extract. After, an in vivo assay was carried out with European seabass juveniles fed selected diets (0—control; 0.1%, and 0.4%). In vitro digestibility assays showed that pentoses release increased 45% with 0.4% SSF-BSG extract and 25% with Natugrain supplemented diets, while amino acids release was not affected. A negative interaction between endogenous fish enzymes and SSF-BSG extract was observed in both diets. The in vivo digestibility assay corroborated in vitro data. Accordingly, the dietary supplementation with 0.4% SSF-BSG increased the digestibility of dry matter, starch, cellulose, glucans, and energy and did not affect protein digestibility. The present work showed the high potential of BSG to produce an added-value functional supplement with high carbohydrases activity and its potential contribution to the circular economy by improving the nutritional value of low-cost and sustainable ingredients that can be included in aquafeeds.

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Sustainable Production of Lignocellulolytic Enzymes in Solid-State Fermentation of Agro-Industrial Waste: Application in Pumpkin (Cucurbita maxima) Juice Clarification

Agronomy ◽

10.3390/agronomy11122379 ◽

2021 ◽

Vol 11 (12) ◽

pp. 2379

Author(s):

Priya Rana ◽

Baskaran Stephen Inbaraj ◽

Sushma Gurumayum ◽

Kandi Sridhar

Keyword(s):

Solid State ◽

Wheat Straw ◽

Rice Bran ◽

Wheat Bran ◽

Solid State Fermentation ◽

Industrial Waste ◽

Low Cost ◽

Principal Component ◽

Enzyme Concentration ◽

Lignocellulolytic Enzymes

Valorization of agro-industrial waste through greener and biotechnological processes are promising approaches to minimize the generation of agro-industrial waste. Therefore, the study aimed to produce lignocellulolytic enzymes from agro-industrial waste under solid-state fermentation (SSF) conditions and study their application in the clarification of pumpkin juice. The SSF was performed with three different combinations of wheat bran + rice bran (WBRB), wheat bran + wheat straw (WBWS), and rice bran + wheat straw (RBWS) as dry solid substrates (1:1) using Fusarium oxysporum (MTCC 7229). The protein, carboxymethyl cellulase (CMCase), and xylanase contents ranged from 0.98–3.90 mg/g, 5.89–6.84 U/g substrate, and 10.08–13.77 U/g substrate, respectively in different agro-industrial waste as substrates (WBRB, WBWS, RBWS, and control). The increase in enzyme concentration (0.50–2.40%) added to pumpkin juice exhibited an increased juice yield (16.30–55.60%), reduced browning index (1.03–0.70), and an increase in clarity (5.31–13.77 %T), which was further confirmed by a total variance of 84.83% by principal component analysis. Thus, the low-cost lignocellulolytic enzymes can be produced from agro-industrial waste that might have applications in food and beverage industries. Hence, this approach could be used as a long-term sustainable and circular source to valorize agro-industrial waste towards the greener future and the preservation of ecosystems.

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Changes in in-vitro digestibility of orange peels and distillery grape stalks after solid-state fermentation by higher fungi

Bioresource Technology ◽

10.1016/0960-8524(93)90137-z ◽

1993 ◽

Vol 45 (1) ◽

pp. 17-20 ◽

Cited By ~ 13

Author(s):

L. Nicolini ◽

C. Volpe ◽

A. Pezzotti ◽

A. Carilli

Keyword(s):

Solid State ◽

Solid State Fermentation ◽

In Vitro Digestibility ◽

Orange Peels ◽

Grape Stalks

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Upgrading wheat straw with urea at a tropical temperature: effects of amount of urea and moisture on in vitro digestibility and pH

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200594046 ◽

1996 ◽

Vol 1996 ◽

pp. 212-212

Author(s):

I.U. Haq ◽

E. Owen

Keyword(s):

Wheat Straw ◽

Urea Solution ◽

In Vitro Digestibility ◽

Ammonia Treatment ◽

Urea Treatment ◽

Cow Urine ◽

The Cost ◽

The Tropics ◽

On Farm

Urea-ammonia treatment of straws in the tropics involves mixing 1.0 kg of air dry straw with 1.0 kg of a 40 g/kg urea solution and storing under plastic for at least 4 weeks (Schiere and Ibrahim, 1989). The economics of treatment is dependent on the cost of urea. Treatment cost would reduce, if on-farm-produced urine, e.g. cow urine, could be used as a source of urea. However cow urine is dilute and may contain only 10 g/kg urea or less (Owen, 1993). The present study therefore investigated varying concentrations of urea solution for treating wheat straw at a tropical temperature.

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Fibre degradation of wheat straw by Pleurotus erygnii under low moisture conditions during solid-state fermentation

Letters in Applied Microbiology ◽

10.1111/lam.13104 ◽

2019 ◽

Vol 68 (2) ◽

pp. 182-187 ◽

Cited By ~ 1

Author(s):

P.W. Baker ◽

A. Charlton ◽

M.D.C. Hale

Keyword(s):

Solid State ◽

Wheat Straw ◽

Solid State Fermentation ◽

Fibre Degradation ◽

Moisture Conditions

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Trametes suaveolens as ligninolytic enzyme producer

Zbornik Matice srpske za prirodne nauke ◽

10.2298/zmspn1324437k ◽

2013 ◽

pp. 437-444 ◽

Cited By ~ 3

Author(s):

Aleksandar Knezevic ◽

Ivan Milovanovic ◽

Mirjana Stajic ◽

Jelena Vukojevic

Keyword(s):

Enzyme Activity ◽

Solid State ◽

Wheat Straw ◽

Solid State Fermentation ◽

Nitrogen Concentration ◽

Pollution Prevention ◽

Ligninolytic Enzyme ◽

Species Selection ◽

Submerged Cultivation ◽

Phenol Red

Species of the genus Trametes represent one of the most efficient lignin-degraders which can be attributed to a well developed ligninolytic enzyme system. Current trends are screening of ability of new species to produce these enzymes, as well as the optimization of conditions for their overproduction. Therefore, the aim of the study was to evaluate the potential of T. suaveolens to synthesize laccase and Mn-oxidizing peroxidases during fermentation of the selected plant raw materials. Level of enzyme activities was measured on 7, 10 and 14th day of submersion, as well as the solid-state fermentation of wheat straw and oak sawdust in the presence of NH4NO3 in previously determined optimal nitrogen concentration of 25 mM. The enzyme activity was determined spectrophotometrically using ABTS and phenol red as the substrates. The highest level of laccase activity (1087.1 U/L) was noted after 7 days of wheat straw solid-state fermentation, while during the submerged cultivation the production of the enzyme was not noted. Submerged cultivation in oak sawdust-enriched medium was the optimal for activity of Mn-dependent peroxidase (1767.7 U/L on day 14) and Mn-independent peroxidase (1113.7 U/L on day 7). Introduction of T. suaveolens to produce ligninolytic enzyme represented the base for further study, as well as the determination of relation between enzyme activity and rate of lignin degradation. It could lead to greater possibility of fungal species selection with high delignification capacity, which could take participation in sustainable production of food, feed, fibres, and energy, environmentally friendly pollution prevention, and bioremediation.

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Feature-Based Molecular Networking Analysis of the Metabolites Produced by in vitro Solid-State Fermentation Reveals Pathways for the Bioconversion of Epigallocatechin Gallate

10.26434/chemrxiv.12124206.v3 ◽

2020 ◽

Author(s):

Hao-Fen Xie ◽

Ya-Shuai Kong ◽

Ru-Ze Li ◽

Hong Zhang ◽

Lu-Lu Liu ◽

...

Keyword(s):

Solid State ◽

Solid State Fermentation ◽

Epigallocatechin Gallate ◽

Oxidation Products ◽

Molecular Networking ◽

Hygrothermal Effect ◽

Ring Fission ◽

Feature Based ◽

Ring Oxidation

Flavan-3-ol B-ring fission derivatives (FBRFDs) are secondary metabolites that contribute to the unique properties of fermented dark teas. However, the FBRFD precursors and biochemistry are unclear. Fungal strains cultured from Fuzhuan brick tea (FBT) were incubated in an in vitro solid-state fermentation system containing β-cyclodextrin-embedded epigallocatechin gallate (EGCG), a potential precursor of FBRFDs. The produced metabolites were analyzed through a combination of targeted chromatographic isolation, non-targeted spectroscopic identification, and Feature-based Molecular Networking (FBMN) in the Global Natural Products Social Molecular Networking (GNPS) platform. Dihydromyricetin was identified for the first time, indicating that fungi possess a flavan-3-ol C-ring oxidation pathway. EGCG was verified as the precursor of dihydromyricetin and FBRFDs such as teadenol A and fuzhuanin A. The conversion was driven by the fungi rather than a hygrothermal effect. Isolates from Pezizomycotina showed much stronger abilities to convert EGCG to the B-/C-ring oxidation products than those from Saccharomycotina or Basidiomycota.

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