scispace - formally typeset
Search or ask a question
Topic

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.


Papers
More filters
Journal ArticleDOI
TL;DR: Improved levels of xylanase and laccase biosynthesis were achieved by co-culturing the mutant P. ostreatus MTCC 1804, which appears productive for the development of mixed enzyme preparation with tremendous potential for biobleaching.

57 citations

Journal ArticleDOI
TL;DR: It is suggested that serine and cysteine residues are not involved in the catalytic mechanisms, and they are metalloproteases in keratinases of endophytic fungal isolates recovered from marine soft coral.
Abstract: Among all endophytic keratinolytic fungal isolates recovered from marine soft coral Dendronephthya hemprichii, Penicillium spp. Morsy1 was selected as the hyperactive keratinolytic strain under solid substrate fermentation of different agriculture and poultry wastes. The optimization of extraction process, physicochemical parameters affecting the keratinase production in solid-state fermentation, and the purified keratinase parameters were studied. Maximum keratinase activity (1,600 U g(-1), initial dry substrate) was recovered from moldy bran with 0.1% Tween 80. The optimized production conditions were rice straw as carbon source, pH of medium 6, growth temperature 26 degrees C, initial moisture content of 80% (v/w), inoculum size of 10(5) spores ml(-1), and an average particle size of the substrate 0.6 mm (3,560 U g(-1), initial dry substrate after 5 days of fermentation). Two types of keratinase (Ahm1 and Ahm2) were purified from the culture supernatant through ammonium sulfate precipitation, DEAE-Sepharose, and gel filtration chromatography. Enzyme molecular weights were 19 kDa (Ahm1) and 40 kDa (Ahm2). The kinetic parameters of purified keratinases were optimized for the hydrolysis of azokeratin by Ahm1 (pH 7.0-8.0, stable in pH range of 6.0 to 8.0 at 50 degrees C) and Ahm2 enzymes (pH 10.0-11.0, stable in pH range of 6.0 to 11.0 at 60-65 degrees C). Whereas inhibitors of serine (phenylmethylsulfonyl fluoride) and cysteine (iodoacetamide) proteases had minor effects on both Ahm1 and Ahm2 activity, both keratinases were strongly inhibited by chelating agents EDTA and EGTA. These findings suggest that serine and cysteine residues are not involved in the catalytic mechanisms, and they are metalloproteases.

57 citations

Journal ArticleDOI
TL;DR: Production of extracellular alkaline protease by a locally isolated fungal species, Rhizopus oryzae, under solid state fermentation was optimized and the maximum enzyme activity under the optimum conditions of temperature, humidity, and spore count was 341 unit/g wheat bran.
Abstract: Production of extracellular alkaline protease by a locally isolated fungal species, Rhizopus oryzae, under solid state fermentation was optimized. The maximum enzyme activity under the optimum conditions of temperature (32 °C), relative humidity (90%–95%), spore count (∼2 × 105/g wheat bran), moisture content of solid substrate (140%) adjusted suitably with salt solution (M-9) of pH 5.5 was 341 unit/g wheat bran.

56 citations

Journal ArticleDOI
TL;DR: This study aimed at optimization of solid-state fermentation by Aspergillus niger CCUG33991 for maximum xylanase production using low-cost agro-industrial residues 1 in tray bioreactor by exploring the effects of particle size, initial moisture content and temperature in trayBioreactor.
Abstract: Xylanases encompass a broad spectrum of industrial applications like food, animal feed, textile and biofuel. This study aimed at optimization of solid-state fermentation by Aspergillus niger CCUG33991 for maximum xylanase production using low-cost agro-industrial residues 1 in tray bioreactor. SSF 2 was performed using wheat bran, sorghum stover, corn cob and soybean meal in flasks for investigation of appropriate substrate, initial pH, media composition and minerals solution. Thereafter, the obtained results combined with results of earlier experiments were used for exploring the effects of particle size, initial moisture content and temperature in tray bioreactor. OFAT method 3 was followed to select optimum level of each parameter. Next, effect of air-drying and pelleting condition were tested on enzyme stability. Finally, the extracted enzymes were subjected to zymography. The highest xylanase activity of 2919±174 U/g-IDW 4 at 48 h was achieved using wheat bran with particle size range of 0.3–0.6 mm, initial moisture level of 70%, moistened by distilled water containing 1% (v/v) glycerol and 1% (w/v) of (NH4)2SO4, and controlled bed temperature in the range of 28–35 °C with surface aeration. As a result, a 2.5-fold higher and 24 h faster xylanase production in trays than in flasks was attained. The enzyme also showed a great deal of stability to air-drying and pelleting condition. Zymogram analysis confirmed multiple isoforms of xylanase. SSF in tray bioreactor is a potential method for xylanase production. Wheat bran as low-cost, time-saving and xylan-containing hemicellulosic agro-waste is preferable to use as the carbon and energy sources for maximum production of xylanase.

56 citations

Journal ArticleDOI
TL;DR: These liquor starters are reported as a new functionally microbial resource, which can be used for discovering thermophilic and aerobic enzymes and for food and feed preservation.
Abstract: Traditional Chinese liquor (Baijiu) solid state fermentation technology has lasted for several thousand years. The microbial communities that enrich in liquor starter are important for fermentation. However, the microbial communities are still under-characterized. In this study, 454 pyrosequencing technology was applied to comprehensively analyze the microbial diversity, function and dynamics of two most-consumed liquor starters (Jiang- and Nong-flavor) during production. In total, 315 and 83 bacterial genera and 72 and 47 fungal genera were identified in Jiang- and Nong-flavor liquor starter, respectively. The relatively high diversity was observed when the temperature increased to 70 and 62 °C for Jiang- and Nong-flavor liquor starter, respectively. Some thermophilic fungi have already been isolated. Microbial communities that might contribute to ethanol fermentation, saccharification and flavor development were identified and shown to be core communities in correlation-based network analysis. The predictively functional profile of bacterial communities showed significant difference in energy, carbohydrate and amino acid metabolism and the degradation of aromatic compounds between the two kinds of liquor starters. Here we report these liquor starters as a new functionally microbial resource, which can be used for discovering thermophilic and aerobic enzymes and for food and feed preservation.

56 citations


Network Information
Related Topics (5)
Fermentation
68.8K papers, 1.2M citations
89% related
Cellulase
16.1K papers, 479.5K citations
87% related
DPPH
30.1K papers, 759.9K citations
82% related
Bacillus subtilis
19.6K papers, 539.4K citations
81% related
Anaerobic digestion
21.8K papers, 575K citations
81% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023196
2022382
2021208
2020266
2019293
2018306