Advances in Engineering Strategies for Enhanced Production of Lipid in Rhodosporidium sp. from Lignocellulosics and Other Carbon Sources

2020 ◽  
pp. 507-519
Author(s):  
R. Saini ◽  
K. Hegde ◽  
S. K. Brar ◽  
C. R. Soccol
Keyword(s):  
Carbon Sources ◽  
Enhanced Production

scholarly journals Enhanced Production and in situ Product Recovery of Fusicocca-2,10(14)-Diene from Yeast

Fermentation ◽  
2018 ◽  
Vol 4 (3) ◽  
pp. 65 ◽  
Author(s):  
Lisa Halka ◽  
Rolf Wichmann
Keyword(s):  
Chemical Synthesis ◽  
Oxygen Supply ◽  
Carbon Sources ◽  
Product Recovery ◽  
Yeast Fermentation ◽  
In Situ Extraction ◽  
In Situ Product Recovery ◽  
Enhanced Production ◽  
Oxygen Conditions

Fusicocca-2,10(14)-diene (FCdiene) is a tricyclic diterpene which has many pharmaceutical applications, for example, it is a precursor for different anticancer drugs, including fusicoccin A. Chemical synthesis of this diterpene is not economical as it requires 14 steps with several stereospecific reactions. FCdiene is naturally produced at low titers in phytopathogenic filamentous fungi. However, production of FCdiene can be achieved via expression of fusicoccadiene synthase in yeast. The objective of this study is to increase FCdiene production by optimizing the yeast fermentation process. Our preliminary fermentations showed influences of carbon sources, buffer agents, and oxygen supply on FCdiene production. Buffer agents as well as oxygen supply were investigated in detail at 0.2 and 1.8 L cultivation volumes. Using glucose as the carbon source, FCdiene concentrations were increased to 240 mgFCdiene/L by optimizing pH and oxygen conditions. In situ extraction and adsorption techniques were examined at the 0.2 L scale to determine if these techniques could improve FCdiene yields. Different adsorbents and solvents were tested with in situ product recovery and 4-fold increases in FCdiene productivity could be shown. The results generated in this work provide a proof-of-concept for the fermentative production of FCdiene from S. cerevisiae as a practical alternative to chemical synthesis.

scholarly journals Enhanced Production of Ethanol from Red Potatoes Grown in Hilly Regions of Nepal Using Various Nitrogen Sources

2014 ◽  
Vol 2 (1) ◽  
pp. 41-44 ◽  
Author(s):  
Jarina Joshi
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Carbon Source ◽  
Ammonium Sulphate ◽  
Sodium Nitrate ◽  
Maximum Yield ◽  
Carbon Sources ◽  
Ammonium Phosphate ◽  
Nitrogen Sources ◽  
Available Nitrogen ◽  
Enhanced Production

Ammonium sulphate, ammonium phosphate, sodium nitrate, urea and glycine were the five different commonly available nitrogen sources used at different concentration ranging from 0.5 to 4% w/v to produce ethanol in batch culture. Potato paste made from red potatoes grown in hilly regions of Nepal was used as carbon source. Prior to fermentation all carbon sources were saccharified enzymatically using α- amylase at pH 5 and temperature 55oC. Maximum yield of ethanol 5.2% was obtained at a temperature of 30oC and pH 5.0 without exogeneous supply of nitrogen. There is slight decrease in concentration when temperature is decreased to 25oC but a drastic decrease in concentration when temperature is increased beyond optimum. All the exogeneously supplied nitrogen sources found to enhance ethanol production and cell viability when yeast strain Saccharomyces cerevisiae isolated from brewer’s yeast was used. Ammonium sulphate was found as best nitrogen supplement among them. Maximum ethanol percentage of 8.3 was observed at pH 5.0 and temperature 30oC with Ammonium sulphate concentration of 2%.DOI: http://dx.doi.org/10.3126/ijasbt.v2i1.9191Int J Appl Sci Biotechnol, Vol. 2(1): 41-44

Organic acids: Versatile stress response roles in plants

2021 ◽  
Author(s):  
Poonam Panchal ◽  
Anthony J Miller ◽  
Jitender Giri
Keyword(s):  
Organic Acids ◽  
Stress Tolerance ◽  
Stress Responses ◽  
Metal Tolerance ◽  
Plant Stress ◽  
Carbon Sources ◽  
Toxic Metal ◽  
Enhanced Production ◽  
Plant Stress Responses ◽  
Plant Stress Tolerance

Abstract Organic acids (OAs) are central to cellular metabolism. Many plant stress responses involve exudation of OAs at the root-soil interface that can improve soil mineral acquisition and toxic metal tolerance. Because of their simple structure, the Low Molecular Weight Organic Acids (LMWOAs) are widely studied. We discuss the conventional roles of OAs, along with some newly emerging roles in plant stress tolerance. OAs are more versatile in their role in plant stress tolerance and are efficient chelating agents when compared with other acids, such as amino acids. Root OA exudation is important in soil carbon sequestration. These functions are key processes combating climate change and helping with more sustainable food production. We briefly review the mechanisms behind enhanced biosynthesis, secretion and regulation of these activities under different stresses. Also, an outline of the transgenic approaches targeted towards the enhanced production and secretion of OAs is provided. A re-occurring theme of OAs in plant biology is their roles as either ‘acids’ modifying pH or ‘chelators’ binding metals or as ‘carbon sources’ for microbes. We argue that these multiple functions are key factors for understanding these molecules important roles in plant stress biology. Finally, we contemplate how the functions of OAs in plant stress responses can be made use of and what the important unanswered questions are.

scholarly journals Enhanced Production and Quantitative Evaluation of Nigericin from the Algerian Soil-Living Streptomyces youssoufiensis SF10 Strain

Fermentation ◽  
2019 ◽  
Vol 5 (1) ◽  
pp. 13 ◽  
Author(s):  
Nassima Leulmi ◽  
Denise Sighel ◽  
Andrea Defant ◽  
Karima Khenaka ◽  
Abderrahmane Boulahrouf ◽  
...  
Keyword(s):  
High Performance ◽  
Biological Activities ◽  
Carbon Sources ◽  
Culture Conditions ◽  
Quantitative Detection ◽  
Evaporative Light Scattering Detector ◽  
Streptomyces Species ◽  
Enhanced Production ◽  
Evaporative Light Scattering ◽  
Antitumor Properties

Nigericin, one of the main ionophoric polyethers produced by various Streptomyces strains, presents relevant biological activities including antibacterial and recently studied antitumor properties. This work describes the influence of different culture conditions on the production of this metabolite by Streptomyces sp. SF10, isolated from a semi-arid soil sample collected at Chélia Mountain, in Khenchela (Northeastern Algeria) and identified as Streptomyces youssoufiensis. The extracts from the strain, cultured in a solid state or submerged fermentation conditions, using several carbon sources at different pH values, in the presence or absence of iron (II) sulfate and in co-culture with other Streptomyces species, were analyzed using a high-performance liquid chromatography (HPLC) system equipped with an evaporative light scattering detector (ELSD). The best culture conditions provided a concentration of nigericin of 0.490 ± 0.001 mg/mL in the extract. The HPLC-ELSD method, optimized here for the quantitative detection of nigericin, can find wider applications in the analysis of several other metabolites characterized by a similar polycyclic polyether structure or, more generally, by the lack of significant chromophores in their molecular structure.

scholarly journals Enhanced production of inulinase from Xanthomonas campestris pv. phaseoli

2010 ◽  
Author(s):  
◽  
Kameshnee Naidoo
Keyword(s):  
Xanthomonas Campestris ◽  
Large Scale ◽  
Specific Activity ◽  
Carbon Sources ◽  
Gel Filtration ◽  
Catalytic Efficiency ◽  
Scale Production ◽  
Inulin Hydrolysis ◽  
Enhanced Production ◽  
Good Potential

Xanthomonas campestris pv phaseoli produced an extracellular endoinulinase on various carbon sources. The highest inulinase production of 9.24 ± 0.03 IU ml¯¹by X. campestris pv. phaseoli was attained using an optimized medium comprising of 3% sucrose and 2.5% tryptone. Inulinase production in X. campestris pv. phaseoli was further enhanced through ethylmethanesulfonate mutagenesis. The resulting mutant, X. campestris pv. phaseoli KM 24 demonstrated enhanced inulinase production of 22.09 ± 0.03 IU ml¯¹after 24 h, which was 2.4 – fold higher than that of the wild type. Inulinase production by this mutant was scaled up in a 5 L fermenter yielding a final activity of 21.87 ± 0.03 IU ml¯¹with an inulinase/invertase (I/S) ratio of 2.6 after 18 h. Maximum volumetric (21 865 IU 1¯¹ h¯¹) and specific (119 025 IU g¯¹ h¯¹) productivities of inulinase were attained in a fermenter after 18h growth. Inulin hydrolysis by the crude inulinase and subsequent detection of mono- and oligosaccharides indicated the presence of an endoinulinase. The extracellular endoinulinase from the mutant KM 24 was purified to homogeneity by gel filtration chromatography and had a specific activity of 174.74U/mg. the optimum pH and temperature of the purified enzyme were found to be 6.0 and 50°C, respectively. The enzyme was stable up to 60°C, retaining over 60% activity for 30 min, but activity rapidly declined at temperatures above 60°C. The pure inulinase enzyme was also found to be stable between pH 6-9. The Lineweaver-Burk plots showed that the apparent Km and Vmax values of the inulinase for inulin were 1.15 mg/ml and 15µM/min, respectively. The Kcat value was found to be 0.145 min¯¹ with an enzyme catalytic efficiency of 0.126 mg¯¹.ml.min¯¹.This mutant demonstrated good potential for large scale production of inulinase and fructooligosaccharides.

scholarly journals Chemical Characterization and Physical and Biological Activities of Rhamnolipids Produced by Pseudomonas aeruginosa BN10

2011 ◽  
Vol 66 (7-8) ◽  
pp. 394-402
Author(s):  
Nelly Christova ◽  
Boryana Tuleva ◽  
Rashel Cohen ◽  
Galya Ivanova ◽  
Georgy Stoev ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Biological Activities ◽  
Pure Water ◽  
Carbon Sources ◽  
Chemical Characterization ◽  
Critical Micellar Concentration ◽  
Antimicrobial Activities ◽  
Chemical Structures ◽  
Enhanced Production ◽  
Pharmaceutical Industries

Pseudomonas aeruginosa BN10 isolated from hydrocarbon-polluted soil was found to produce rhamnolipids when cultivated on 2% glycerol, glucose, n-hexadecane, and n-alkanes. The rhamnolipids were partially purified on silica gel columns and their chemical structures elucidated by combination of one- and two-dimensional 1H and 13C NMR techniques and ESI-MS analysis. Eight structural rhamnolipid homologues were identified: Rha-C10- C8, Rha-C10-C10, Rha-C10-C12:1, Rha-C10-C12, Rha2-C10-C8, Rha2-C10-C10, Rha2-C10-C12:1, and Rha2-C10-C12. The chemical composition of the rhamnolipid mixtures produced on different carbon sources did not vary with the type of carbon source used. The rhamnolipid mixture produced by Pseudomonas aeruginosa BN10 on glycerol reduced the surface tension of pure water from 72 to 29 mN m-1 at a critical micellar concentration of 40 mg l-1, and the interfacial tension was 0.9 mN m-1. The new surfactant product formed stable emulsions with hydrocarbons and showed high antimicrobial activity against Gram-positive bacteria. The present study shows that the new strain Pseudomonas aeruginosa BN10 demonstrates enhanced production of the di-rhamnolipid Rha2-C10-C10 on all carbon sources used. Due to its excellent surface and good antimicrobial activities the rhamnolipid homologue mixture from Pseudomonas aeruginosa BN10 can be exploited for use in bioremediation, petroleum and pharmaceutical industries.

Activation of cytochrome c to a peroxidase compound I-type intermediate by H2O2: relevance to redox signalling in apoptosis

2004 ◽  
Vol 71 ◽  
pp. 97-106 ◽  
Author(s):  
Mark Burkitt ◽  
Clare Jones ◽  
Andrew Lawrence ◽  
Peter Wardman
Keyword(s):  
Cytochrome C ◽  
Hydroxyl Radical ◽  
Redox Regulation ◽  
Chemotherapeutic Agents ◽  
Tyrosyl Radical ◽  
Compound I ◽  
Definitive Evidence ◽  
Enhanced Production ◽  
Physico Chemical

The release of cytochrome c from mitochondria during apoptosis results in the enhanced production of superoxide radicals, which are converted to H2O2 by Mn-superoxide dismutase. We have been concerned with the role of cytochrome c/H2O2 in the induction of oxidative stress during apoptosis. Our initial studies showed that cytochrome c is a potent catalyst of 2′,7′-dichlorofluorescin oxidation, thereby explaining the increased rate of production of the fluorophore 2′,7′-dichlorofluorescein in apoptotic cells. Although it has been speculated that the oxidizing species may be a ferryl-haem intermediate, no definitive evidence for the formation of such a species has been reported. Alternatively, it is possible that the hydroxyl radical may be generated, as seen in the reaction of certain iron chelates with H2O2. By examining the effects of radical scavengers on 2′,7′-dichlorofluorescin oxidation by cytochrome c/H2O2, together with complementary EPR studies, we have demonstrated that the hydroxyl radical is not generated. Our findings point, instead, to the formation of a peroxidase compound I species, with one oxidizing equivalent present as an oxo-ferryl haem intermediate and the other as the tyrosyl radical identified by Barr and colleagues [Barr, Gunther, Deterding, Tomer and Mason (1996) J. Biol. Chem. 271, 15498-15503]. Studies with spin traps indicated that the oxo-ferryl haem is the active oxidant. These findings provide a physico-chemical basis for the redox changes that occur during apoptosis. Excessive changes (possibly catalysed by cytochrome c) may have implications for the redox regulation of cell death, including the sensitivity of tumour cells to chemotherapeutic agents.

Influence of carbon sources on the plant regeneration in wheat (Triticum aestivum L.)

2006 ◽  
Vol 34 (1) ◽  
pp. 613-616
Author(s):  
Henriett Oskolás Kovácsné ◽  
Pál Pepó
Keyword(s):  
Triticum Aestivum ◽  
Plant Regeneration ◽  
Carbon Sources ◽  
Triticum Aestivum L
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