Brewer's spent grain (BSG) is the main brewery industry by-product, with potential applications in the feed and food industries due to its carbohydrate composition. In addition, the lignocellulosic nature of BSG makes it an adequate substrate for carbohydrases production. In this work, solid-state fermentation (SSF) of BSG was performed with Aspergillus ibericus, a non-mycotoxin producer fungus with a high capacity to hydrolyze the lignocellulosic matrix of the agro-industrial by-products. SSF was performed at different scales to produce a crude extract rich in cellulase and xylanase. The potential of the crude extract was tested in two different applications: -(1) - the enzymatic hydrolysis of the fermented BSG and (2) - as a supplement in aquafeeds. SSF of BSG increased the protein content from 25% to 29% (w/w), while the fiber content was reduced to 43%, and cellulose and hemicellulose contents were markedly reduced to around 15%. The scale-up of SSF from 10 g of dry BSG in flasks to 50 g or 400 g in tray-type bioreactors increased 55% and 25% production of cellulase and xylanase, up to 323 and 1073 U g-1 BSG, respectively. The optimum temperature and pH of maximal activities were found to be 55°C and pH 4.4 for xylanase and 50°C and pH 3.9 for cellulase, cellulase being more thermostable than xylanase when exposed at temperatures from 45°C to 60°C. A Box-Behnken factorial design was applied to optimize the hydrolysis of the fermented BSG by crude extract. The crude extract load was a significant factor in sugars release, highlighting the role of hydrolytic enzymes, while the load of fermented BSG, and addition of a commercial β-glucosidase were responsible for the highest phenolic compounds and antioxidant activity release. The lyophilized crude extract (12,400 and 1050 U g-1 lyophilized extract of xylanase and cellulase, respectively) was also tested as an enzyme supplement in aquafeed for European seabass (Dicentrarchus labrax) juveniles. The dietary supplementation with the crude extract significantly improved feed and protein utilization. The processing of BSG using biological treatments, such as SSF with A. ibericus, led to the production of a nutritionally enriched BSG and a crude extract with highly efficient carbohydrases capable of hydrolyzing lignocellulosic substrates, such as BSG, and with the potential to be used as feed enzymes with remarkable results in improving feed utilization of an important aquaculture fish species.

Centre of Biological Engineering University of Minho Campus de Gualtar Braga Portugal

Departamento de Biologia Faculdade de Ciências Universidade Do Porto Rua Do Campo Alegre Ed FC4 Porto Portugal

Department of Chemistry and Biochemistry Mendel University in Brno Brno Czech Republic

Interdisciplinary Centre of Marine and Environmental Research Terminal de Cruzeiros Do Porto de Leixões Av General Norton de Matos Matosinhos Portugal

Zobrazit více v PubMed

Adiguzel G., Faiz O., Sisecioglu M., Sari B., Baltaci O., Akbulut S., et al. (2019). A Novel Endo-β-1,4-Xylanase from Pediococcus Acidilactici GC25; Purification, Characterization and Application in Clarification of Fruit Juices. Int. J. Biol. Macromolecules 129, 571–578. 10.1016/j.ijbiomac.2019.02.054 PubMed DOI

Ajila C. M., Gassara F., Brar S. K., Verma M., Tyagi R. D., Valéro J. R. (2011). Polyphenolic Antioxidant Mobilization in Apple Pomace by Different Methods of Solid-State Fermentation and Evaluation of its Antioxidant Activity. Food Bioproc. Technol. 5 (7), 2697–2707. 10.1007/s11947-011-0582-y DOI

Aliyu S., Bala M. (2013). Brewer’s Spent Grain: A Review of its Potentials and Applications. Afr. J. Biotechnol. 10 (3), 324–331. 10.4314/ajb.v10i3 DOI

Alonso-Riaño P., Sanz Diez M. T., Blanco B., Beltrán S., Trigueros E., Benito-Román O. (2020). Water Ultrasound-Assisted Extraction of Polyphenol Compounds from Brewer's Spent Grain: Kinetic Study, Extract Characterization, and Concentration. Antioxidants 9 (3), 265–318. 10.3390/antiox9030265 PubMed DOI PMC

Ang S. K., E.M. S., Y. A., A.A S., M.S M. (2013). Production of Cellulases and Xylanase by Aspergillus Fumigatus SK1 Using Untreated Oil Palm Trunk Through Solid State Fermentation. Process Biochem. 48 (9), 1293–1302. 10.1016/j.procbio.2013.06.019 DOI

Anwar A., Wan A. H., Omar S., El-Haroun E., Davies S. J. (20202019). The Potential of a Solid-State Fermentation Supplement to Augment White Lupin (Lupinus Albus) Meal Incorporation in Diets for Farmed Common Carp (Cyprinus carpio). Aquacult. Rep. 17, 100348. 10.1016/j.aqrep.2020.100348 DOI

Astolfi V., Astolfi A. L., Mazutti M. A., Rigo E., Di Luccio M., Camargo A. F., et al. (2019). Cellulolytic Enzyme Production from Agricultural Residues for Biofuel Purpose on Circular Economy Approach. Bioproc. Biosyst. Eng. 42 (5), 677–685. 10.1007/s00449-019-02072-2 PubMed DOI

Besson M., De Boer I. J. M., Vandeputte M., Van Arendonk J. A. M., Quillet E., Komen H., et al. (2017). Effect of Production Quotas on Economic and Environmental Values of Growth Rate and Feed Efficiency in Sea Cage Fish Farming. PLoS ONE 12 (3), e0173131–15. 10.1371/journal.pone.0173131 PubMed DOI PMC

Birsan R. I., Wilde P., Waldron K. W., Rai D. K. (2019). Recovery of Polyphenols from Brewer's Spent Grains. Antioxidants 8 (9), 380–392. 10.3390/antiox8090380 PubMed DOI PMC

Bowyer P. H., El-Haroun E. R., Salim H. S., Davies S. J. (2020). Benefits of a Commercial Solid-State Fermentation (SSF) Product on Growth Performance, Feed Efficiency and Gut Morphology of Juvenile Nile tilapia (Oreochromis niloticus) Fed Different UK Lupin Meal Cultivars. Aquaculture 523 (March), 735192. 10.1016/j.aquaculture.2020.735192 DOI

Canedo M. S., de Paula F. G., da Silva F. A., Vendruscolo F. (2016). Protein Enrichment of Brewery Spent Grain from Rhizopus Oligosporus by Solid-State Fermentation. Bioproc. Biosyst. Eng. 39 (7), 1105–1113. 10.1007/s00449-016-1587-8 PubMed DOI

Castillo S., Gatlin D. M. (2015). Dietary Supplementation of Exogenous Carbohydrase Enzymes in Fish Nutrition: A Review. Aquaculture 435 (January 2015), 286–292. 10.1016/j.aquaculture.2014.10.011 DOI

Chen Z., Liu Y., Zaky A. A., Liu L., Chen Y., Li S., et al. (2019). Characterization of a Novel Xylanase from Aspergillus flavus with the Unique Properties in Production of Xylooligosaccharides. J. Basic Microbiol. 59 (4), 351–358. 10.1002/jobm.201800545 PubMed DOI

Crowley D., O'Callaghan Y., McCarthy A. L., Connolly A., Fitzgerald R. J., O'Brien N. M. (2017). Aqueous and Enzyme-Extracted Phenolic Compounds from Brewers' Spent Grain (BSG): Assessment of Their Antioxidant Potential. J. Food Biochem. 41 (3), e12370–11. 10.1111/jfbc.12370 DOI

Daniel N. (2018). A Review on Replacing Fish Meal in Aqua Feeds Using Plant Protein Sources. Int. J. Fish. Aquat. Stud. 6 (2), 164–179.

Dawood M. A. O., Koshio S. (2019). Application of Fermentation Strategy in Aquafeed for Sustainable Aquaculture. Rev. Aquacult. 12, 987–1002. 10.1111/raq.12368 DOI

Delabona P. d. S., Pirota R. D. P. B., Codima C. A., Tremacoldi C. R., Rodrigues A., Farinas C. S. (2013). Effect of Initial Moisture Content on Two Amazon Rainforest Aspergillus Strains Cultivated on Agro-Industrial Residues: Biomass-Degrading Enzymes Production and Characterization. Ind. Crops Prod. 42 (1), 236–242. 10.1016/j.indcrop.2012.05.035 DOI

Diógenes A. F., Castro C., Carvalho M., Magalhães R., Estevão-Rodrigues T. T., Serra C. R., et al. (2018). Exogenous Enzymes Supplementation Enhances Diet Digestibility and Digestive Function and Affects Intestinal Microbiota of Turbot (Scophthalmus maximus) Juveniles Fed Distillers' Dried Grains with Solubles (DDGS) Based Diets. Aquaculture 486 (December 2017), 42–50. 10.1016/j.aquaculture.2017.12.013 DOI

Dudek M., Świechowski K., Manczarski P., Koziel J. A., Białowiec A. (2019). The Effect of Biochar Addition on the Biogas Production Kinetics from the Anaerobic Digestion of Brewers' Spent Grain. Energies 12 (8), 1518–1522. 10.3390/en12081518 DOI

Dulf F. V., Vodnar D. C., Socaciu C. (2016). Effects of Solid-State Fermentation with Two Filamentous Fungi on the Total Phenolic Contents, Flavonoids, Antioxidant Activities and Lipid Fractions of Plum Fruit (Prunus Domestica L.) By-Products. Food Chem. 209, 27–36. 10.1016/j.foodchem.2016.04.016 PubMed DOI

Ezeilo U. R., Wahab R. A., Mahat N. A. (2020). Optimization Studies on Cellulase and Xylanase Production by Rhizopus Oryzae UC2 Using Raw Oil Palm Frond Leaves as Substrate Under Solid State Fermentation. Renew. Energ. 156, 1301–1312. 10.1016/j.renene.2019.11.149 DOI

Farcas A. C., Socaci S. A., Mudura E., Dulf F. V., Vodnar D. C., Tofana M., et al. (2017). Exploitation of Brewing Industry Wastes to Produce Functional Ingredients. Brewing Technol. 2, 64. 10.5772/32009 DOI

Fernandes H., Salgado J. M., Martins N., Peres H., Oliva-Teles A., Belo I. (2019). Sequential Bioprocessing of Ulva Rigida to Produce Lignocellulolytic Enzymes and to Improve its Nutritional Value as Aquaculture Feed. Bioresour. Technol. 281, 277–285. 10.1016/j.biortech.2019.02.068 PubMed DOI

Ferreira J. A., Mahboubi A., Lennartsson P. R., Taherzadeh M. J. (2016). Waste Biorefineries Using Filamentous Ascomycetes Fungi: Present Status and Future Prospects. Bioresour. Technol. 215, 334–345. 10.1016/j.biortech.2016.03.018 PubMed DOI

Gatlin D. M., Barrows F. T., Brown P., Dabrowski K., Gaylord T. G., Hardy R. W., et al. (2007). Expanding the Utilization of Sustainable Plant Products in Aquafeeds: A Review. Aquaculture Res. 38 (6), 551–579. 10.1111/j.1365-2109.2007.01704.x DOI

Getu K., Getachew A., Berhan T., Getnet A. (2020). Supplementary Value of Ensiled Brewers Spent Grain Used as Replacement to Cotton Seed Cake in the Concentrate Diet of Lactating Crossbred Dairy Cows. Trop. Anim. Health Prod. 52, 3675–3683. 10.1007/s11250-020-02404-5 PubMed DOI

Gowthaman M. K., Krishna C., Moo-Young M. (2001). Fungal Solid State Fermentation - An Overview. Appl. Mycol. Biotechnol. 1 (C), 305–352. 10.1016/S1874-5334(01)80014-9 DOI

Hakobyan L., Gabrielyan L., Blbulyan S., Trchounian A. (2021). The Prospects of Brewery Waste Application in Biohydrogen Production by Photofermentation of Rhodobacter Sphaeroides. Int. J. Hydrogen. Energ. 46, 289–296. 10.1016/j.ijhydene.2020.09.184 DOI

Jahromi M. F., Liang J. B., Rosfarizan M., Goh Y. M., Shokryazdan P., Ho Y. W. (2011). Efficiency of Rice Straw Lignocelluloses Degradability by Aspergillus Terreus ATCC 74135 in Solid State Fermentation. Afr. J. Biotechnol. 10 (21), 4428–4435. 10.5897/AJB10.2246 DOI

Lakhundi S., Siddiqui R., Khan N. A. (2015). Cellulose Degradation: A Therapeutic Strategy in the Improved Treatment of Acanthamoeba Infections. Parasites Vectors 8 (1), 1–16. 10.1186/s13071-015-0642-7 PubMed DOI PMC

Leite P., Salgado J. M., Venâncio A., Domínguez J. M., Belo I. (2016). Ultrasounds Pretreatment of Olive Pomace to Improve Xylanase and Cellulase Production by Solid-State Fermentation. Bioresour. Technol. 214, 737–746. 10.1016/j.biortech.2016.05.028 PubMed DOI

Leite P., Silva C., Salgado J. M., Belo I. (2019). Simultaneous Production of Lignocellulolytic Enzymes and Extraction of Antioxidant Compounds by Solid-State Fermentation of Agro-Industrial Wastes. Ind. Crops Prod. 137 (May), 315–322. 10.1016/j.indcrop.2019.04.044 DOI

Li J. S., Li J. L., Wu T. T. (2009). Effects of Non-Starch Polysaccharides Enzyme, Phytase and Citric Acid on Activities of Endogenous Digestive Enzymes of tilapia (Oreochromis niloticus × Oreochromis aureus). Aquacult. Nutr. 15 (4), 415–420. 10.1111/j.1365-2095.2008.00606.x DOI

Liguori R., Pennacchio A., Vandenberghe L. P. d. S., De Chiaro A., Birolo L., Soccol C. R., et al. (2021). Screening of Fungal Strains for Cellulolytic and Xylanolytic Activities Production and Evaluation of Brewers' Spent Grain as Substrate for Enzyme Production by Selected Fungi. Energies 14 (15), 4443. 10.3390/en14154443 DOI

Lizardi-Jiménez M. A., Hernández-Martínez R. (2017). Solid State Fermentation (SSF): Diversity of Applications to Valorize Waste and Biomass. 3 Biotech. 7 (1). 10.1007/s13205-017-0692-y PubMed DOI PMC

Llimós J., Martínez-Avila O., Marti E., Corchado-Lopo C., Llenas L., Gea T. (2020). Brewer's Spent Grain Biotransformation to Produce Lignocellulolytic Enzymes and Polyhydroxyalkanoates in a Two-Stage Valorization Scheme. Biomass Convers. Biorefinery. 10.1007/s13399-020-00918-4 DOI

Maas R. M., Verdegem M. C. J., Schrama J. W. (2019). Effect of Non‐Starch Polysaccharide Composition and Enzyme Supplementation on Growth Performance and Nutrient Digestibility in Nile tilapia (Oreochromis niloticus). Aquacult Nutr. 25 (3), 622–632. 10.1111/anu.12884 DOI

Magalhães R., Díaz-Rosales P., Diógenes A. F., Enes P., Oliva-Teles A., Peres H. (2018). Improved Digestibility of Plant Ingredient-Based Diets for European Seabass (Dicentrarchus labrax) with Exogenous Enzyme Supplementation. Aquacult Nutr. 24 (4), 1287–1295. 10.1111/anu.12666 DOI

Magalhães R., Lopes T., Martins N., Díaz-Rosales P., Couto A., Pousão-Ferreira P., et al. (2016). Carbohydrases Supplementation Increased Nutrient Utilization in White Seabream (Diplodus sargus) Juveniles Fed High Soybean Meal Diets. Aquaculture 463 (May 2016), 43–50. 10.1016/j.aquaculture.2016.05.019 DOI

Manisha, Yadav S. K. (2017). Technological Advances and Applications of Hydrolytic Enzymes for Valorization of Lignocellulosic Biomass. Bioresour. Technol. 245, 1727–1739. 10.1016/j.biortech.2017.05.066 PubMed DOI

Martins S., Mussatto S. I., Martínez-Avila G., Montañez-Saenz J., Aguilar C. N., Teixeira J. A. (2011). Bioactive Phenolic Compounds: Production and Extraction by Solid-State Fermentation. A Review. Biotechnol. Adv. 29 (3), 365–373. 10.1016/j.biotechadv.2011.01.008 PubMed DOI

Méndez-Hernández J. E., Loera O., Méndez-Hernández E. M., Herrera E., Arce-Cervantes O., Soto-Cruz N. Ó. (2019). Fungal Pretreatment of Corn Stover by Fomes Sp. EUM1: Simultaneous Production of Readily Hydrolysable Biomass and Useful Biocatalysts. Waste Biomass Valor. 10 (9), 2637–2650. 10.1007/s12649-018-0290-1 DOI

Miller G. L. (1959). Use of Dinitrosalicylic Acid Reagent for Determination of Reducing Sugar. Anal. Chem. 31, 426–428. 10.1021/ac60147a030 DOI

Mussatto S. I. (2014). Brewer's Spent Grain: A Valuable Feedstock for Industrial Applications. J. Sci. Food Agric. 94 (7), 1264–1275. 10.1002/jsfa.6486 PubMed DOI

Nahid P., Vossoughi M., Roostaazad R., Ahmadi M., Zarrabi A., Hosseini S. M. (2012). Production of Glucoamylase by Aspergillus niger Under Solid State Fermentation. Ije 25 (1), 1–7. 10.5829/idosi.ije.2012.25.01b.01 DOI

Nargotra P., Sharma V., Gupta M., Kour S., Bajaj B. K. (2018). Application of Ionic Liquid and Alkali Pretreatment for Enhancing Saccharification of Sunflower Stalk Biomass for Potential Biofuel-Ethanol Production. Bioresour. Technol. 267 (May), 560–568. 10.1016/j.biortech.2018.07.070 PubMed DOI

Narra M., Dixit G., Divecha J., Kumar K., Madamwar D., Shah A. R. (2014). Production, Purification and Characterization of a Novel GH 12 Family Endoglucanase from Aspergillus Terreus and its Application in Enzymatic Degradation of Delignified Rice Straw. Int. Biodeterioration Biodegradation 88, 150–161. 10.1016/j.ibiod.2013.12.016 DOI

Nocente F., Taddei F., Galassi E., Gazza L. (2019). Upcycling of Brewers' Spent Grain by Production of Dry Pasta with Higher Nutritional Potential. Lwt 114 (April), 108421. 10.1016/j.lwt.2019.108421 DOI

Novelli P. K., Barros M. M., Pezzato L. E., de Araujo E. P., de Mattos Botelho R., Fleuri L. F. (2017). Enzymes Produced by Agro-Industrial Co-Products Enhance Digestible Values for Nile tilapia (Oreochromis niloticus): A Significant Animal Feeding Alternative. Aquaculture 481 (August), 1–7. 10.1016/j.aquaculture.2017.08.010 DOI

Oliva-Teles A., Enes P., Peres H. (2015). Replacing Fishmeal and Fish Oil in Industrial Aquafeeds for Carnivorous Fish. Feed Feeding Practices Aquacult., 203–233. 10.1016/b978-0-08-100506-4.00008-8 DOI

Opazo R., Ortúzar F., Navarrete P., Espejo R., Romero J. (2012). Reduction of Soybean Meal Non-Starch Polysaccharides and α-Galactosides by Solid-State Fermentation Using Cellulolytic Bacteria Obtained from Different Environments. PLoS ONE 7 (9), e44783. 10.1371/journal.pone.0044783 PubMed DOI PMC

Outeiriño D., Costa-Trigo I., Pinheiro de Souza Oliveira R., Pérez Guerra N., Domínguez J. M. (2019). A Novel Approach to the Biorefinery of Brewery Spent Grain. Process Biochem. 85 (June), 135–142. 10.1016/j.procbio.2019.06.007 DOI

Patel A. K., Singhania R. R., Sim S. J., Pandey A. (2019). Thermostable Cellulases: Current Status and Perspectives. Bioresour. Technol. 279, 385–392. 10.1016/j.biortech.2019.01.049 PubMed DOI

Paz A., Outeiriño D., Pérez Guerra N., Domínguez J. M. (2019). Enzymatic Hydrolysis of Brewer's Spent Grain to Obtain Fermentable Sugars. Bioresour. Technol. 275 (December 2018), 402–409. 10.1016/j.biortech.2018.12.082 PubMed DOI

Pitol L. O., Finkler A. T. J., Dias G. S., Machado A. S., Zanin G. M., Mitchell D. A., et al. (2017). Optimization Studies to Develop a Low-Cost Medium for Production of the Lipases of Rhizopus Microsporus by Solid-State Fermentation and Scale-Up of the Process to a Pilot Packed-Bed Bioreactor. Process Biochem. 62 (July), 37–47. 10.1016/j.procbio.2017.07.019 DOI

Procentese A., Raganati F., Olivieri G., Russo M. E., Rehmann L., Marzocchella A. (2018). Deep Eutectic Solvents Pretreatment of Agro-Industrial Food Waste. Biotechnol. Biofuels 11 (1), 1–12. 10.1186/s13068-018-1034-y PubMed DOI PMC

Rayhane H., Josiane M., Gregoria M., Yiannis K., Nathalie D., Ahmed M., et al. (2019). From Flasks to Single Used Bioreactor: Scale-Up of Solid State Fermentation Process for Metabolites and Conidia Production by Trichoderma Asperellum. J. Environ. Manage. 252 (October 2019), 109496. 10.1016/j.jenvman.2019.109496 PubMed DOI

Rojas-Chamorro J. A., Romero I., López-Linares J. C., Castro E. (2020). Brewer's Spent Grain as a Source of Renewable Fuel Through Optimized Dilute Acid Pretreatment. Renew. Energ. 148, 81–90. 10.1016/j.renene.2019.12.030 DOI

Roy S., Dutta T., Sarkar T. S., Ghosh S. (2013). Novel Xylanases from Simplicillium Obclavatum MTCC 9604: Comparative Analysis of Production, Purification and Characterization of Enzyme from Submerged and Solid State Fermentation. SpringerPlus 2 (1), 1–10. 10.1186/2193-1801-2-382 PubMed DOI PMC

Ruviaro A. R., Barbosa P. d. P. M., Macedo G. A. (2019). Enzyme-Assisted Biotransformation Increases Hesperetin Content in Citrus Juice By-Products. Food Res. Int. 124 (December 2017), 213–221. 10.1016/j.foodres.2018.05.004 PubMed DOI

Sakhuja D., Ghai H., Rathour R. K., Kumar P., Bhatt A. K., Bhatia R. K. (2021). Cost-Effective Production of Biocatalysts Using Inexpensive Plant Biomass: A Review. 3 Biotech. 11 (6). 10.1007/s13205-021-02847-z PubMed DOI PMC

San Martin D., Orive M., Iñarra B., Castelo J., Estévez A., Nazzaro J., et al. (2020). Brewers' Spent Yeast and Grain Protein Hydrolysates as Second-Generation Feedstuff for Aquaculture Feed. Waste Biomass Valor. 11 (10), 5307–5320. 10.1007/s12649-020-01145-8 DOI

Serra R., Cabanes F. J., Perrone G., Castella G., Venancio A., Mule G., et al. (2006). Aspergillus ibericus: A New Species of Section Nigri Isolated from Grapes. Mycologia 98 (2), 295–306. 10.3852/mycologia.98.2.295 PubMed DOI

Sinha A. K., Kumar V., Makkar H. P. S., De Boeck G., Becker K. (2011). Non-Atarch Polysaccharides and Their Role in Fish Nutrition - A Review. Food Chem. 127 (4), 1409–1426. 10.1016/j.foodchem.2011.02.042 DOI

Socaci S. A., Fărcaş A. C., Diaconeasa Z. M., Vodnar D. C., Rusu B., Tofană M. (2018). Influence of the Extraction Solvent on Phenolic Content, Antioxidant, Antimicrobial and Antimutagenic Activities of Brewers' Spent Grain. J. Cereal Sci. 80, 180–187. 10.1016/j.jcs.2018.03.006 DOI

Sousa D., Venâncio A., Belo I., Salgado J. M. (2018). Mediterranean Agro-Industrial Wastes as Valuable Substrates for Lignocellulolytic Enzymes and Protein Production by Solid-State Fermentation. J. Sci. Food Agric. 98 (14), 5248–5256. 10.1002/jsfa.9063 PubMed DOI

Troell M., Naylor R. L., Metian M., Beveridge M., Tyedmers P. H., Folke C., et al. (2014). Does Aquaculture Add Resilience to the Global Food System? Proc. Natl. Acad. Sci. U.S.A. 111 (37), 13257–13263. 10.1073/pnas.1404067111 PubMed DOI PMC

Vasconcellos V. M., Tardioli P. W., Giordano R. L. C., Farinas C. S. (2015). Production Efficiency versus Thermostability of (Hemi)cellulolytic Enzymatic Cocktails from Different Cultivation Systems. Process Biochem. 50 (11), 1701–1709. 10.1016/j.procbio.2015.07.011 DOI

Webb C. (2017). Design Aspects of Solid State Fermentation as Applied to Microbial Bioprocessing. Jabb 4 (1). 10.15406/jabb.2017.04.00094 DOI

Xavier B., Sahu N. P., Pal A. K., Jain K. K., Misra S., Dalvi R. S., et al. (2012). Water Soaking and Exogenous Enzyme Treatment of Plant-Based Diets: Effect on Growth Performance, Whole-Body Composition, and Digestive Enzyme Activities of Rohu, Labeo Rohita (Hamilton), Fingerlings. Fish. Physiol. Biochem. 38 (2), 341–353. 10.1007/s10695-011-9511-2 PubMed DOI