Solid-state fermentation

About: Solid-state fermentation is a research topic. Over the lifetime, 5311 publications have been published within this topic receiving 113337 citations.

Production of milk clotting protease by a local isolate of Mucor circinelloides under SSF using agro-industrial wastes

Abstract: Agro-industrial residues, a cheap source of energy have high potential in the area of fermentation for the production of enzymes. Twenty agro-industrial residues were evaluated to check the possibility of potential utilization of substrates in SSF for milk clotting enzyme protease production by Mucor circinelloides. In this study, dhal husk holds the greatest promise for cost effective production of the milk clotting enzyme. The dhal husk supported maximum milk clotting protease production, and yield was improved with the supplementation of sucrose and yeast extract as carbon and nitrogen source, respectively. Among all the physico-chemical parameters tested, the best results were obtained in a medium having moisture content of 20% at pH 7.0, when inoculated with 30% of spore suspension and incubated at 30°C for 5 days. The activity was increased further on addition of Ca2+, Cu2+, and Mg2+ ions. The purified milk-clotting protease obtained from M. circinelloides was successfully applied and compared with commercial rennet in the manufacture of a cheddar cheese.

Glucosinolate degradation by Aspergillus clavatus and Fusarium oxysporum in liquid and solid-state fermentation

Abstract: Two fungal strains, Aspergillus clavatus II-9 and Fusarium oxysporum @ 149, proved to be capable of degrading sinigrin and sinalbin During the degradation of sinigrin by whole cells of the Aspergillus strain, allylcyanide accumulated in the liquid incubation mixture After a maximum concentration had been reached, the concentration of allylcyanide decreased as a result of its instability in the medium used Incubation of cell-free extracts with sinigrin resulted in accumulation of glucose and allylisothiocyanate, suggesting that myrosinase is involved Experiments with intact cells and cell-free extracts indicate the formation of an as yet unknown intermediate When sinigrin was degraded by the Aspergillus strain in mustard seed meal under solid-state fermentation (SSF) conditions, no accumulation of allylcyanide or allylisothiocyanate was measured Degradation of sinigrin by F oxysporum @ 149 did not result in accumulation of intermediates, neither in liquid incubation mixtures nor in mustard seed meal under SSF conditions Sinigrin was not degraded during incubation with cell-free extracts of F oxysporum @ 149 Degradation of sinalbin by A clavatus and F oxysporum was measured during fermentation of yellow mustard seed meal under SSF conditions Both fungi are useful for laboratory-scale SSF of mustard seed meal, thus opening new perspectives for a cost effective detoxification process for raw feed materials

Production, partial characterization, and immobilization in alginate beads of an alkaline protease from a new thermophilic fungus Myceliophthora sp.

Abstract: Thermophilic fungi produce thermostable enzymes which have a number of applications, mainly in biotechnological processes. In this work, we describe the characterization of a protease produced in solidstate (SSF) and submerged (SmF) fermentations by a newly isolated thermophilic fungus identified as a putative new species in the genus Myceliophthora. Enzyme-production rate was evaluated for both fermentation processes, and in SSF, using a medium composed of a mixture of wheat bran and casein, the proteolytic output was 4.5-fold larger than that obtained in SmF. Additionally, the peak of proteolytic activity was obtained after 3 days for SSF whereas for SmF it was after 4 days. The crude enzyme obtained by both SSF and SmF displayed similar optimum temperature at 50°C, but the optimum pH shifted from 7 (SmF) to 9(SSF). The alkaline protease produced through solid-state fermentation (SSF), was immobilized on beads of calcium alginate, allowing comparative analyses of free and immobilized proteases to be carried out. It was observed that both optimum temperature and thermal stability of the immobilized enzyme were higher than for the free enzyme. Moreover, the immobilized enzyme showed considerable stability for up to 7 reuses.

Saccharification and hydrolytic enzyme production of alkali pre-treated wheat bran by Trichoderma virens under solid state fermentation

Abstract: In continuation of our previously interest in the saccharification of agriculture wastes by Bacillus megatherium in solid state fermentation (SSF), we wish to report an investigation and comparative evaluation among Trichoderma sp. for the saccharification of four alkali-pretreated agricultural residues and production of hydrolytic enzymes, carboxymethyl cellulase (CMCase), filter paperase (FPase), pectinase (PGase) and xylanase (Xylase) in SSF. The optimization of the physiological conditions of production of hydrolytic enzymes and saccharification content from Trichoderma virens using alkali-pretreated wheat bran was the last goal. The physico-chemical parameters of SSF include incubation time, incubation temperature, moisture content of the substrate, incubation pH, supplementation with carbon and nitrogen sources were optimized. Saccharification of different solid state fermentation sources wheat bran, date's seeds, grass and palm leaves, were tested for the production of fermentable sugar by Trichoderma sp. The maximum production of hydrolytic enzymes CMCase, FPase, PGase and Xylase and saccharification content were obtained on wheat bran. Time course, moisture content, optimum temperature, optimum pH, supplementation with carbon and nitrogen sources were optimized to achieve the maximum production of the hydrolytic enzymes, protein and total carbohydrate of T. virens using alkali pre-treated wheat bran. The maximum production of CMCase, FPase, PGase, Xylase, protein and carbohydrate content was recorded at 72 h of incubation, 50-70 % moisture, temperature 25-35 °C and pH 5. The influence of supplementary carbon and nitrogen sources was studied. While lactose and sucrose enhanced the activity of PGase from 79.2 to 582.9 and 632.6 U/g, starch inhibited all other enzymes. This was confirmed by maximum saccharification content. Among the nitrogen sources, yeast extract and urea enhanced the saccharification content and CMCase, PGase and Xylase. The results of this study indicated that alkali pre-treated wheat bran was a better substrate for saccharification and production of hydrolytic enzymes CMCase, FPase, PGase and xylase by T. virens compared to other alkali-pretreated agricultural residues tested.