Search

One of the limiting parameters of the mycelial fungi submerged cultivation for the synthesis of metabolites used for medical, food and industrial purposes is the hydrodynamic conditions of submerged cultivation. The effect of mechanical stirring rate on the yield of metabolites was investigated on the example of cultivation of mycelial fungi Aspergillus awamori - glucoamylase producer. It was found that the maximum yield of the enzyme was observed at the stirring speed of turbine impeller amounting to 60-120 rpm. As the stirring speed increased, the amount of synthesized metabolite decreased, which is a consequence of the destruction of the mycelial cells. The connection between the decrease in glucoamylase synthesis and the rejuvenation of the culture caused by its recovery from fragments of the destroyed mycelium and the subsequent increase in the amount of biomass was shown. At the same time, the degree of destruction was shown by the increase in the amount of nucleic acids in the filtrate. The relationship between the degree of destruction of mycelial cells, determined by the amount of nucleic acids in the filtrate under extreme conditions of ultrasonic disintegration, and the viability of the culture was also demonstrated. The amount of viable cells increased at first (until the saturation of the culture fluid with nucleic acids), and then began to gradually decrease. The obtained results can serve as a starting point for further studies of the possibility of stimulating the primary accumulation of biomass of micromycetes by ultrasound. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate antitumor and antioxidant properties of water-soluble polysaccharides from submerged mycelium of Flammulina velutipes grown under optimized conditions. The optimization of the nutrient medium composition allowed to increase the biomass yield by more than 2 times (up to 35 g/l) and to reduce the time of the cultivation process. The submerged mycelium of F.velutipes strain Fv-1 contained 14.8% of a water-soluble polysaccharides, 31.6% of proteins, 2.5% of total lipids, vitamins B (B1, B5, Bg). The polysaccharides contained glucose, galactose, fucose, mannose, xylose, rhamnose. The proteins contained all the essential amino acids except for tryptophan. Dry powder of the submerged mycelium, water extract of the mycelium and total fraction of the water-soluble polysaccharides demonstrated the antitumor activity against murine lymphocytic leukemia Р 388 in vivo. The antitumor activity of the substances was mainly due to the polysaccharides, since their purification increased the tumor growth inhibition. The maximum tumor growth inhibition by the water-soluble polysaccharides amounted to 94%. The total fraction of the water-soluble polysaccharides from F.velutipes strain Fv-1 demonstrated antioxidant activity. The antioxidant capacity (AOC) of the water-soluble fraction from F.velutipes was higher than that of the water-soluble polysaccharides from the submerged mycelium of Grifola frondosa, but inferior to the AOC of the water-soluble polysaccharides from the submerged mycelium of Ganoderma lucidum.

Fractions of water soluble and alkali soluble polysaccharides, as well as fucogalactan, a water soluble polysaccharide, and xylomannan, an alkali soluble polysaccharide, were isolated from the Ganoderma lucidum submerged mycelium. When administered orally, the polysaccharides showed antitumor activity in vivo on murine models of solid tumors. Xylomannan and fucogalactan showed the highest antitumor activity. Sensitivity to xylomannan was more pronounced in adenocarcinoma Ca755 as compared to the T-cell lymphocytic leukemia P388. The antitumor activity of the water soluble polysaccharides total fractions from the mycelium and fruiting bodies of the G.lucidum strain was almost identical. The maximum antitumor effect of the mycelium water soluble polysaccharides total fraction was observed with the use of the daily dose of 2 mg/kg.

Aims: Investigation of the influence of cultivation time and sea buckthorn press cake (Hippophaë rhamnoides) dosage on mycelium yield of Inonotus obliquus in submerged cultivation and on the yield, monomer composition, and macromolecular properties of the exopolysaccharides (EPS) from culture media and intracellular polysaccharides (IPS) extracted from mycelia. Methods and Results: Supplementation at 5 g l−1 combined with cultivation time of 250 h granted highest yield increase in mycelia (by 122%). The supplementation reduced extraction yield and decreased the molecular weight of the main IPS population. The supplementation increased production and molecular weight of EPS. The relative content of arabinose and rhamnose in EPS positively correlated with dosage of the press cake. The press cake supplementation increased the content of galacturonic acid in IPS, but not in EPS. Conclusion: Sea buckthorn press cake is a food industry fibrous side stream with high oil content. It increases the cultivation yield of Inonotus obliquus mycelium and influences the produced polysaccharides. Significance and Impact of the Study: Mycelium is a resource of bioactive polysaccharides, attracting the interest of nutraceutical companies. Sea buckthorn press cake is a promising supplement for increasing mycelium production. The utilization of this agricultural side stream would therefore favour circular economy. [ABSTRACT FROM AUTHOR]

Based on the assessment of the trophic needs of basidiomycete Flammulina velutipes and the optimization of the composition of the nutrient medium using design of experimental approach, the yield of the submerged biomass of the fungus was increased to 41 g/L, the duration of the cultivation process was reduced to 5 days. For this purpose, the 24 full factorial design, the Box– Wilson steep ascent method and the construction of the response surface were used. Using the method of scanning electron microscopy, it was shown that the studied F. velutipes strain grew in the form of small spherical pellets with a diameter of 1–2 mm on an optimized medium. The surface of the pellets was loose; the inner part was filled with hyphae tightly adjacent to each other. The center of the pellets had no cavity. F. velutipes pellets were formed by septate hyphae with clamp connections. The micromorphological characteristics of the submerged F. velutipes mycelium ensured a high diffusion of nutrients and oxygen into the pellets and their maximum filling of the volume of the culture medium. [ABSTRACT FROM AUTHOR]

Mushroom fruiting bodies have been used as food and food-flavouring materials for centuries for their unique and subtle flavour. However, the whole cycle from mycelium colonization to the fruit-body formation is time-consuming and involves extensive labour. Submerged cultivation of fungi can be a promising alternative for obtaining potent substances for successful utilization in the composition of functional foods. Submerged culture is a speedy process that yields quality mushroom mycelia, considering the alternative of cultivation that takes much more time to produce fruiting bodies. Moreover, the culturing of mycelia on synthetic media is a convenient approach to obtain fungal biomass. Presence of bioactive components in mushroom mycelium makes it an attractive ingredient that is now used as dietary supplements or nutraceuticals. This review focuses on the optimum growth conditions required by mycelia for enhanced quality and yield prospects along with the biological mechanisms responsible for their therapeutic properties and their applications.

The effect of different cultivation methods on the content of ganoderic acids of 7 species, 10 strains of the Ganoderma genus (Ganoderma applanatum 1899; Ganoderma сarnosum 2502; Ganoderma lucidum 1904; Ganoderma resinaceum 2477, 2503; Ganoderma sinense 2516; Ganoderma tsugae 1848, 2024, 2566, Ganoderma oregonense 2560) genus fungi from the IBK Mushroom Culture Collection M.G. Kholodny Institute of Botany of National Academy of Sciences of Ukraine was investigated. It has been shown that the submerged cultivation method is more efficient for the accumulation of ganoderic acids for five strains. In the mycelium of the strain G. sinense 2516 was the highest content of ganoderic acids – 25.2 ± 1.5 mg / g. The productivity (yeld) of ganoderic acids synthesis is much higher with using the submerged culture cultivation method for mycelium of all used species and strains since the use of this method provides the accumulation of much more biomass in comparison with the static liquid cultivation method. The highest yield amount of ganoderic acids was in the mycelium of the G. tsugae 2024 and G. tsugae 2566 species, namely: 0.35 ± 0.019 and 0.36 ± 0.028 g / l. It was proved that the modified extraction method significantly reduces the extraction time of ganoderic acids. Extraction time is reduced from 14 to 2 days. For the G. sinense 2516 and G. tsugae 2024 strains was determined content of the ganoderic acids and their yield in dynamics of grows in the submerged culture on 6, 8, 10, 12, 14, 16, 18 and 20 day of cultivation. The highest amount of the ganoderic acids content was accumulated by the mycelium of the strain G. sinense 2516 – it was 26.4 ± 1.5 mg / g on the 14th day of cultivation. The highest yield of the ganoderic acids was in G. sinense 2516 on 14th day, and G. tsugae 2024 mycelium on the 16th day of cultivation with the next numbers 0.6 ± 0.031, 0.62 ± 0.033 and 0.62 ± 0.027 g/l. [ABSTRACT FROM AUTHOR]

• Mushroom mycelium are considered as nutraceuticals and pharmaceuticals. • Convenient to grow, more nutritious and therapeutically stronger. • Consists of bio actives such as Polysaccharides (especially β-glucans), terpenoids and sterols. • Applications as functional foods, commercial health products and flavoring agents. Mushroom fruiting bodies have been used as food and food-flavouring materials for centuries for their unique and subtle flavour. However, the whole cycle from mycelium colonization to the fruit-body formation is time-consuming and involves extensive labour. Submerged cultivation of fungi can be a promising alternative for obtaining potent substances for successful utilization in the composition of functional foods. Submerged culture is a speedy process that yields quality mushroom mycelia, considering the alternative of cultivation that takes much more time to produce fruiting bodies. Moreover, the culturing of mycelia on synthetic media is a convenient approach to obtain fungal biomass. Presence of bioactive components in mushroom mycelium makes it an attractive ingredient that is now used as dietary supplements or nutraceuticals. This review focuses on the optimum growth conditions required by mycelia for enhanced quality and yield prospects along with the biological mechanisms responsible for their therapeutic properties and their applications. [ABSTRACT FROM AUTHOR]

Bioactive compounds obtained from Coriolus versicolor ( Trametes versicolor (L.: Fr) Lloyd, 1920.) mushrooms cultivated in a stirred-tank bioreactor were tested to determine their antimicrobial potential. Extracellular polysaccharides were isolated from the fermentation broth by ethanol precipitation. A methanol extract was prepared from mycelium. The cultivation conditions applied during the fermentation process provided for significant biomass 6.63 ± 0.31 g dry weight L − 1 and yield of extracellular polysaccharides (EPS) (0.74 ± 0.12 g L − 1 ). Microscopic analyses revealed that the mycelium grew predominately in the form of fluffy pellets. The methanol extract demonstrated very good activity against all the tested Gram-positive bacteria. Bacillus spizizeni and Staphylococcus epidermidis were the most sensitive strains (minimum inhibitory concentration (MIC) < 0.3125 mg mL − 1 ). Among the Gram-negative bacteria, Yersinia enterocolitica had the lowest MIC value, 5 mg mL − 1 . Microbicidal activity of mycelia methanol extract was established in seven out of ten tested Gram-negative bacteria strains with minimum bactericidal concentration (MBC) values ranged from 20 to 40 mg mL − 1 . Enterococcus faecalis and Staphylococcus aureus showed higher sensitivity to the extracellular polysaccharides (MIC values 2.5 mg mL − 1 ). FTIR analysis revealed a more complex chemical composition of the methanol extract compared to EPS, which might explain the better antibacterial activity of the methanol extract. Our results suggested that the submerged cultivation of Coriolus versicolor followed by ethanol precipitation of EPS and the methanol extraction of mycelia can be a promising process to obtain biological active compounds with significant antimicrobial activity. Industrial Relevance Mushrooms contain a large number of chemicals with potential use as antimicrobial compounds. One of the biggest challenges for providing biologically active compounds from mushrooms is short-term process standardization with a low risk for contamination. Submerged culture cultivation is the best choice for providing antimicrobial compounds from mushrooms. The submerged culture method represents an effective and energy-efficient means to produce novel antibacterial compound from mushrooms. Antibacterial activity testing revealed that methanol extract and isolated exopolysaccharides exhibited strong antibacterial activity, especially against Gram-positive bacteria. [ABSTRACT FROM AUTHOR]

A simplified submerged airlift cultivation was established for the production of biomass from Agaricus subrufescens. In this work, soluble polysaccharides extracted from fungal mycelium, fruiting bodies, and the residual culture media were concentrated by nanofiltration. Total and high molar mass polysaccharides and soluble solids were determined in the concentrate for the three extracts. Additionally, the permeate flow, the influences of temperature and pressure, and the resistance to the permeate flow during filtration were also evaluated. A yield of 5.5 g/L of biomass with 35 % glucose conversion was obtained when 0.5 g/L of initial inoculum was employed. Average specific speed of growth was 0.4/day, with biomass productivity of about 0.76 g/(L day). Nanofiltration has yielded polysaccharide increases of 85, 82, and 92 % in the extracts from fruiting bodies, mycelium, and liquid media, respectively. A reduction in the permeate flow was observed during filtration, and it was compensated by higher pressures and temperatures. The higher resistance to the permeate flux was caused by polarization due to concentration (polarized gel layer), reaching values of 88 % for the culture media. Maximal resistance caused by the membrane reached values of 40 % for the extract from the fruiting bodies. On the other hand, resistance caused by fouling was responsible for less than 3.5 %. In conclusion, nanofiltration is efficient to concentrate these functional compounds extracted from A. subrufescens and can, therefore, be applied in different biotechnological areas. [ABSTRACT FROM AUTHOR]

A simplified submerged airlift cultivation was established for the production of biomass from Agaricus subrufescens. In this work, soluble polysaccharides extracted from fungal mycelium, fruiting bodies, and the residual culture media were concentrated by nanofiltration. Total and high molar mass polysaccharides and soluble solids were determined in the concentrate for the three extracts. Additionally, the permeate flow, the influences of temperature and pressure, and the resistance to the permeate flow during filtration were also evaluated. A yield of 5.5 g/L of biomass with 35 % glucose conversion was obtained when 0.5 g/L of initial inoculum was employed. Average specific speed of growth was 0.4/day, with biomass productivity of about 0.76 g/(L day). Nanofiltration has yielded polysaccharide increases of 85, 82, and 92 % in the extracts from fruiting bodies, mycelium, and liquid media, respectively. A reduction in the permeate flow was observed during filtration, and it was compensated by higher pressures and temperatures. The higher resistance to the permeate flux was caused by polarization due to concentration (polarized gel layer), reaching values of 88 % for the culture media. Maximal resistance caused by the membrane reached values of 40 % for the extract from the fruiting bodies. On the other hand, resistance caused by fouling was responsible for less than 3.5 %. In conclusion, nanofiltration is efficient to concentrate these functional compounds extracted from A. subrufescens and can, therefore, be applied in different biotechnological areas. [ABSTRACT FROM AUTHOR]

Our goal was to optimize the growth conditions of submerged mycelial cultures of Lentinula edodes (Shiitake mushroom) in order to obtain a new dietary supplement enriched in selenium We designed a process technology in which mycelial cultures were cultivated in media composed of beet molasses, 10%; liquid stillage, 5%; corn steep liquor, 0.15%; and KH2PO4, 0.3%, enriched with selenium in concentrations ranging from 0 to 100 μg/mL by the addition of sodium selenite of selenic acid. Se concentrations in mycelial dry mass rose from 0.001 mg/g (mycelia cultivated in media containing no selenium) to 50 mg/g (mycelia cultivated in medium containing 100 μg Se/mL). The highest mycelial specific growth rate (0.46/day) was recorded when the concentration of selenium in the medium was lower than 20 μg/mL. In vitro, estimated Se bioavailabilities from selenized mycelium strongly depended on its preparation in a proper manner and were 60% and 82% for dried mycelium and mycelial lyophilizate, respectively. Our results suggest that these optimized culture conditions could be applied to obtain a new Se-enriched dietary supplement. [ABSTRACT FROM AUTHOR]

Abstract: The effects of medium composition and fermentation parameters on simultaneous production of mycelia and intracellular polysaccharide by medicinal mushroom, Cordyceps jiangxiensis were investigated in shake-flask cultures using desirability functions. The optimal conditions were obtained via the associated desirability as follows: 40g/l of molasses glycerol, 5g/l of peanut steep meal, 6g/l of yeast extract, 1g/l of KH2PO4, 0.5g/l of ZnCl2, 0.5g/l of MgSO4, initial pH at 6, cultivation temperature at 28°C, 200ml of medium working volume in a 500ml flask and 5% (v/v) of inoculum size. Under these conditions, the production titer of mycelia and intracellular polysaccharide reached 24.5 and 8.9g/l, respectively, after a 9-day submerged cultivation. The use of desirability functions was proved effective in optimizing multi-response fermentation processes and it is readily applicable to other fermentation systems. [Copyright &y& Elsevier]

The dependence of the amount of the grown vegetative mycelium of Ganoderma lucidum on the composition of the nutrient medium has been studied under conditions of submerged cultivation. The medium was optimized using full factorial and steepest ascent experimental designs. The addition of two carbon sources to the medium considerably improved the submerged growth of the mushroom. An optimized medium provided for a high yield (20-20.95 g/l) of the morphologically homogeneous mycelium and shortened the cultivation period to 3–4 days. [ABSTRACT FROM AUTHOR]

Original strains of Ganoderma lucidum (W.Curt.:Fr.) Lloyd and G. applanatum (Pers.) Pat. (synonymous G. lipsiense (Batsch) Atk.) from Slovenian habitats were isolated and used for experimental work. In G. applanatum, research was focused on triterpenoid acids. They were isolated from the fruiting bodies of G. applanatum of Istrian origin (BFWS Gaa2), growing on Populus trees. The highest amount of triterpenoid acids was found in the tubes (6.4 mg/g of air-dried weight), followed by the younger dark context layer of the pileus (2.5 mg/g), the older white context layer (0.6 mg/g), and the upper surface of the fruiting body (0.6 mg/g). G. lucidum strain MZKI G97, isolated from the Slovenian forest, was cultivated by solid state cultivation in a horizontal reactor and by submerged liquid substrate cultivation in a 10-L laboratory stirred tank reactor. Using a 17% (wet weight) of 6-day-old vegetative inoculum, up to 17.0 gL-1 of dry fungal biomass was obtained in a fed batch process. From the mycelium biomass, 1.7 gL-1 of extracellular and 0.45 gL-1 of intracellular polysaccharides were isolated, which were mainly β-D-glucans. Polysaccharide fractions, tested in vitro on the induction of cytokine synthesis in primary cultures of human mononuclear cells from a buffy coat of healthy donors, induced 3.0-630 pg mL-1 of TNF-α and 1.23-2.18 pg mL-1 of IFN-γ. [ABSTRACT FROM AUTHOR]

The study was aimed at the mass production of fungal mycelial biomass of Pleurotus eryngii with enhanced nutritional values through submerged cultivation techniques. Using one factor at a time (OFAT), both physical (Temperature, pH, and RPM) and chemical (carbon sources, nitrogen sources, and C/N ratio) parameters were studied in shake flasks and suitable conditions were selected for the production of the mycelial biomass. The optimized parameters were used for mass production of mushroom mycelia in 100 l fermenter. Further, the harvested mushroom mycelia were exposed to UV-B irradiation. The produced mycelial biomass has an enhanced level of micronutrients (Ca, Co & Fe) and vitamin D 2 as compared to its fruiting bodies reported in the literature. The average % composition of ergosterol, protein, crude fat, total ash, moisture, carbohydrate, and crude fiber in dried mycelia was 0.251, 24.52, 6.78, 7.82, 4.86, 18.54 and 55.36 respectively. Vitamin D 2 content increased to 320 μg/g from 4.53 μg/g. The mineral composition of Ca, P, K, Mg were 2273.4, 4114.5, 6951.4, and 917.3 μg/g while micro-elements Fe, Zn, Co, and Cu were found to be 79.34, 32.64, 10.09 and 1.12 μg/g respectively in dried mycelia. • Mass production strategy for Pleurotus eryngii mycelia through submerged cultivation technique. • Synthesis of suitable media and studies on growth conditions for production of micronutrients enriched mycelial biomass. • Characterization of produced mushroom mycelia for its nutritional properties. • Improved nutritional properties of Pleurotus eryngii mycelia (vitamin D 2 and minerals, i.e. Ca, Co and Fe). [ABSTRACT FROM AUTHOR]