Interrelationship among substrate utilization, metabolic productions, and housekeeping-related gene expression levels in Mortierella alpine CBS 754.68.

The impacts of Magnesium oxide nanoparticles (MgONPs) on the expression of 10 potential housekeeping genes of Mortierella alpine were assayed. Actin emerged as the good candidate when Mortierella alpine entered the death phase subsequent to the growth phase while Dihydropteridine reductase and 28 s were identified as suitable candidates when Mortierella alpine remained in the growth phase.

Optimization of chemical conditions for metabolites production by Ganoderma lucidum using response surface methodology and investigation of antimicrobial as well as anticancer activities.

Ganoderma lucidum (G. lucidum) is a medicinal mushroom that is known for its ability to produce compounds with physiological effects on human health. This research was undertaken to amplify the production of bioactive components of G. lucidum under optimal cultivation conditions, obtained in a submerged state and utilized in solid state fermentation, with the purpose of enhancing antimicrobial and anticancer activities. The results indicated that titanium dioxide (TiO2 NPs), magnesium oxide nanoparticles (MgO2 NPs), and B6, along with glucose syrup and CLS syrups, were the most effective for producing GA, while wheat starch and whey protein, along with MgO2 NPs and B6 vitamin, stimulated polysaccharide production using the One Factor at a Time (OFAT) method. After screening, the response surface method (RSM) statistically indicated that the media containing 42.11 g/L wheat starch with 22 g/L whey protein and 50 g/L glucose syrup with 30 g/L CSL were found to be the best conditions for polysaccharide (21.47% of dry weight biomass) and GA (20.35 mg/g dry weight biomass) production, respectively. The moss of the fruit body of G. lucidum produced under optimal GA conditions had the highest diversity in flavonoids and phenolic acids and significant antimicrobial activity against Esherichia coli (E. coli) and Bacillus subtilis (B. subtilis). In addition, the IC50 levels of shell and stem of G. lucidum were 465.3 and 485.7 µg/mL, respectively, while the moss did not reach 50% inhibition. In the end, the statistical approaches utilized in this research to elevate the levels of bioactive components in the fruiting body of G. lucidum produced a promising natural source of antimicrobial and anticancer agents.

Enhancement of oil productivity of Mortierella alpine and investigation into the potential of Pickering oil-in-water emulsions to improve its oxidative stability.

Mortierella alpine is an oleaginous fungi known for its tendency to produce oil and polyunsaturated fatty acid. Initial experiment indicated that magnesium oxide nanoparticles (MgONPs) accelerated glucose consumption and, consequently, oil production. After enhancement of Mortierella alpine CBS 754.68' oil production, the oxidative stability of the oil rich in long-chain polyunsaturated fatty acids (arachidonic acid) encapsulated by modified chitosan (CS) was assayed. To confirm the modification of CS, Fourier transform infrared spectroscopy (FTIR) spectrum indicated that the connection between CS and capric acid (CA) as well as stearic acid (SA) was well formed, leading to a considerable improvement in nanoparticle formation, measured by the SEM photographs, and physical and oxidative stability of emulsions. The oxidative stability of Mortierella alpine' oil emulsion in a period of 20 days at ambient temperature was monitored. Of all treated media, CS-SA nanoparticles were of the most oxidative stability. The rheological tests showed that viscosity behaviors were dominated by elastic behaviors in the impregnating emulsion with unmodified CS at the applied frequencies, and the elastic behavior of the emulsion sample prepared with CS-SA was slightly higher than that of the emulsion prepared with CS-CA. The results of redispersibility indicated that the powdered emulsion stabilized by CS-SA had the lowest water absorption.

Optimization of culture conditions for enhanced Dunaliella salina productions in mixotrophic culture.

Dunaliella salina (D. salina) is a green microalga known for its tendency to produce lipid and ß-carotene. Fatty acid profile, lipid and ß-carotene productions of the microalga D. salina cultivated under different mixotrophic conditions were assayed. Notably, in spite of a broad spectrum of substrates served, mixotrophic cultivations slightly affected the fatty acid composition, and as a result C16:0 and C18:0, C18:1, C18:2 and C18:3 were identified as main fatty acids. Lipid in dry weight biomass (DWB) hit a high of 24.3% at 5% of NaCL and linolenic acid in lipid reached a peak of 9.15% at 15% of NaCL in medium containing glucose and equal amounts of yeast extract and soy bean powder. One-factor-at-a-time was applied to elucidate the substrates which had noticeable impacts on ß-carotene production. Glucose, meat peptone, titanium dioxide nanoparticles (TiO2 NPs), pH 7.5 and 5% NaCL were identified as key process parameters impacting ß-carotene production. Following, the concentration of glucose, meat peptone and TiO2 NPs were optimized by using response surface method. The highest content of ß-carotene, 25.23 mg/g DWB, was obtained in medium composed of (g/L); 22.92 glucose, 5 meat peptone and 0.002 TiO2 NPs.

Optimization of the Production of ε-Poly-L-Lysine by Novel Producer Lactic Acid Bacteria Isolated from Traditional Dairy Products.

New strains of lactic acid bacteria (LAB) were isolated from different traditional dairy products. Six new strains named Lactobacillus delbrueckii strain A01, Lactobacillus delbrueckii subsp. bulgaricus strain D01, Lactobacillus delbrueckii subsp. bulgaricus strain E01, Lactococcus lactis strain G01, Lactobacillus delbrueckii strain C01, and Lactobacillus delbrueckii subsp. bulgaricus strain F01 were identified using 16S rDNA sequencing, morphological and biochemical traits. All strains have been registered in the National Center for Biotechnology Information (NCBI) with accession numbers MN611241.1, MN611300.1, MN611301.1, MN611303.1, MN611241.1, and MN611299.1, respectively. Having found ε-Poly-L-Lysine (ε-PL) in all strains isolated, Lactobacillus delbrueckii strain A01 was identified as an active producer of ε-Poly-L-Lysine (ε-PL). The one-factor-at-a-time method and central composite design were applied to optimize ε-Poly-L-Lysine (ε-PL). A predicted 200 ppm of ε-PL was obtained in the medium containing the lowest level of glucose, 25 g/l, and yeast extract, 6 g/l.

Production, medium optimization, and structural characterization of an extracellular polysaccharide produced by Rhodotorula minuta ATCC 10658.

Several strains of microorganism are capable of converting carbohydrates into extracellular polysaccharide. The preset research is a first effort made to optimize extracellular polysaccharide (CRMEP) by Rhodotorula minuta ATCC 10658 using one factor at time and response surface methods. One factor at time was applied in the initial screening of substrates prior to optimization study. Of all the substrates examined, starch as carbon source and defatted soy bean powder as protein source were discovered to be best for CRMEP production. Response surface analysis revealed that 15 g/L starch and 30g/L defatted soy bean powder were the optimal chemical conditions. The model predicted 13.22 g/L for CRMEP, which went along with the experimentally observed result. Purification of CRMEP by anion-exchange column of DEAE-cellulose yielded RMEP. Structural investigation indicated that the main chain of RMEP was composed of (1 â†’ 3) and (1 â†’ 4)-linked mannopyranosyl residues, with branches attached to O-6 of some (1 â†’ 3)-linked mannopyranosyl residues. The branches were composed of Glcp-(1 â†’ residues.

Statistical Optimization of Culture Conditions for Protein Production by a Newly Isolated Morchella fluvialis.

Morchella fungi are considered a good source of protein. The ITS region was used to identify Morchella isolated in the northern region of Iran. The isolated fungus was very similar to Morchella fluvialis. M. fluvialis was first isolated in Iran. Dried biomass of M. fluvialis contained 9% lipids and 50% polysaccharides. Fatty acid profiles of lipids of M. fluvialis are mainly made up of linoleic acid (C18:2) (62%), followed by palmitic acid (C16:0) (12%). Testosterone (TS) was also detected (0.732 ng/dry weight biomass (DWB)) in the hormone profile of this new isolated species. Then, various protein and carbon sources as variable factors were applied to identify the key substrates, which stimulated protein production using the one-factor-at-a-time method. Key substrates (glucose and soybean) were statistically analyzed to determine the optimum content of the protein and DWB accumulation using response surface methods. The highest protein content (38% DWB) was obtained in the medium containing 80 g/l glucose and 40 g/l soybean powder. Total nutritionally indispensable amino acids and conditionally indispensable amino acids constitute 55.7% crude protein. That is to say, these adequate quantities of essential amino acids in the protein of M. fluvialis make it a good and promising source of essential amino acids for human diet.

Expression analysis for genes involved in arachidonic acid biosynthesis in Mortierella alpina CBS 754.68.

The time courses for production of fungal biomass, lipid, phenolic and arachidonic acid (ARA) as well as expression of the genes involved in biosynthesis of ARA and lipid were examined in Mortierella alpina CBS 754.68. A significant increase in the arachidonic acid content in lipids that coincided with reduced levels of lipid was obtained. Reduced gene expression occurred presumably due to the steady reduction of carbon and nitrogen resources. However, these energy resources were inefficiently compensated by the breakdown of the accumulated lipids that in turn, induced up-regulated expression of the candidate genes. The results further indicated that the expression of the GLELO encoding gene is a rate-limiting step in the biosynthesis of ARA in the early growth phase.

Expression analysis for genes involved in arachidonic acid biosynthesis in Mortierella alpina CBS 754.68

The time courses for production of fungal biomass, lipid, phenolic and arachidonic acid (ARA) as well as expression of the genes involved in biosynthesis of ARA and lipid were examined in Mortierella alpina CBS 754.68. A significant increase in the arachidonic acid content in lipids that coincided with reduced levels of lipid was obtained. Reduced gene expression occurred presumably due to the steady reduction of carbon and nitrogen resources. However, these energy resources were inefficiently compensated by the breakdown of the accumulated lipids that in turn, induced up-regulated expression of the candidate genes. The results further indicated that the expression of the GLELO encoding gene is a rate-limiting step in the biosynthesis of ARA in the early growth phase.