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.

Synthesis of alpha-amylase by Aspergillus oryzae in solid-state fermentation.

Abstract: Spent Brewing Grains (SBG) was evaluated for its efficacy to be used as sole carbon source for the synthesis of alpha-amylase in solid-state fermentation using a fungal strain of Aspergillus oryzae NRRL 6270. Enzyme production was superior when the culture grew on mesophilic temperatures and best yields were at 25 degrees C. At 30 degrees C, yields were almost comparable. Maximum production of alpha-amylase [6870 U/g dry substrate (gds)] was obtained when SSF was carried out at 30 degrees C for 96 h using SBG medium, which had initial moisture of 70% and was inoculated using a spore suspension containing 1 x 10(7) spores/ml. Supplementation of SBG with external carbon sources such as mono-, di and polysaccharides caused repression in enzyme synthesis by the fungal culture.

Solid-State Yeast Fermented Wheat and Oat Bran as A Route for Delivery of Antioxidants.

Abstract: The purpose of our study was to evaluate the potential of solid-state yeast fermentation (SSYF) in improving the phenolic acid content and composition, and the antioxidant activity of commercial wheat bran (WB) and oat bran (OB). The ultrasound-assisted methanolic extracts were compared for their total phenolic content (TPC), phenolics composition, and in vitro antioxidant activity in order to study the effect of fermentation time on the chemical profile and activity of bioactive compounds. The comparative analysis revealed significant differences (p < 0.05) between days of fermentation (0 through 6). The highest TPCs were obtained on day 3 for WB (0.84 ± 0.05 mg of gallic acid equivalents [GAE]/g dry weight [DW]), and on day 4 for OB (0.45 ± 0.02 mg GAE/g DW). The highest relative percentage increase in the phenolics concentration of WB was also registered on day 3 (ferulic acid +56.6%, vanillic acid +259.3%, dihydroxybenzoic acids +161.2%, apigenin-glucoside +15.3%); for OB, this was observed on day 4 (avenanthramide 2f +48.5%, ferulic acid +21.2%). Enhanced antioxidant activities were significantly correlated with the highest TPCs. Our results suggest that SSYF may be a useful procedure for enrichment of antioxidants in cereal bran, considering the design of different functional foods and nutraceuticals.

Lipase Production in Solid-State Fermentation (SSF): Recent Developments and Biotechnological Applications

Abstract: Lipases are the most widely used biocatalysts, because they can catalyze several unnatural and remarkable reactions in non-aqueous media, such as bio-fuel production, production of value-added products such as esters, organic acids, food, beverage, cosmetics and pharmaceutical materials. Solid-state fermentation (SSF) represents an interesting alternative to produce industrial enzymes at lower costs due to the possibility of using inexpensive agro-industrial residues as culture media. This review aims to explore various agriculture byproducts like husk, straw, agricultural raw materials, waste of the oil industry, among others that are locally available and are also costeffective requiring low nutrient supplementation to produce microbial lipase(s) in SSF. Enzyme production is associated with the growth of the bacterial culture. The physico-chemical fermentation parameters such as pH of the medium, moisture content, particle-size, nature of particles and microbial inoculum level play crucial role(s) in lipase production. SSF has gained renewed interest and fresh attention of researchers to develop processes to achieve large-scale enzyme production by solid waste treatment and in its application in the industry to synthesize the products of commercial value.

From stale bread and brewers spent grain to a new food source using edible filamentous fungi.

Abstract: By-products from the food sector with a high load of organic matter present both a waste-handling problem related to expenses and to the environment, yet also an opportunity. This study aims to increase the value of stale bread and brewers spent grain (BSG) by re-introducing these residues to the food production chain by converting them to new protein-enriched products using the edible filamentous fungi Neurospora intermedia and Rhizopusoryzae. After 6 days of solid state fermentation (at 35°C, with a95% relative humidity and moisture content of 40% in the substrate) on stale bread, a nutrient-rich fungal-fermented product was produced. The total protein content, as analyzed by total amino acids, increased from 16.5% in stale sourdough bread to 21.1% (on dry weight basis) in the final product with an improved relative ratio of essential amino acids. An increase in dietary fiber, minerals (Cu, Fe, Zn) and vitamin E, as well as an addition of vitamin D2 (0.89 µg/g dry weight sample) was obtained compared with untreated stale bread. Furthermore, addition of BSG to the sourdough bread with the aim to improve textural changes after fermentation showed promising outcomes. Cultivation of N. intermedia or R. oryzae on stale sourdough bread mixed with 6.5% or 11.8% BSG, respectively, resulted in fungal-fermented products with similar textural properties to a commercial soybean burger. Bioconversion of stale bread and BSG by fungal solid state fermentation to produce a nutrient-enriched food product was confirmed to be a successful way to minimize food waste and protein shortage.