scholarly journals Phosphorus and Nitrogen Limitation as a Part of the Strategy to Stimulate Microbial Lipid Biosynthesis

2021 ◽  
Vol 11 (24) ◽  
pp. 11819
Author(s):  
Katarzyna Wierzchowska ◽  
Bartłomiej Zieniuk ◽  
Dorota Nowak ◽  
Agata Fabiszewska
Keyword(s):  
Lipid Accumulation ◽  
Nitrogen Sources ◽  
Phosphorus Limitation ◽  
Inorganic Phosphorus ◽  
Lipid Biosynthesis ◽  
Medium Composition ◽  
Bioreactor Culture ◽  
Biomass Growth ◽  
Cellular Lipid ◽  
Lipid Yield

Microbial lipids called a sustainable alternative to traditional vegetable oils invariably capture the attention of researchers. In this study, the effect of limiting inorganic phosphorus (KH2PO4) and nitrogen ((NH4)2SO4) sources in lipid-rich culture medium on the efficiency of cellular lipid biosynthesis by Y. lipolytica yeast has been investigated. In batch cultures, the carbon source was rapeseed waste post-frying oil (50 g/dm3). A significant relationship between the concentration of KH2PO4 and the amount of lipids accumulated has been revealed. In the shake-flask cultures, storage lipid yield was correlated with lower doses of phosphorus source in the medium. In bioreactor culture in mineral medium with (g/dm3) 3.0 KH2PO4 and 3.0 (NH4)2SO4, the cellular lipid yield was 47.5% (w/w). Simultaneous limitation of both phosphorus and nitrogen sources promoted lipid accumulation in cells, but at the same time created unfavorable conditions for biomass growth (0.78 gd.m./dm3). Increased phosphorus availability with limited cellular access to nitrogen resulted in higher biomass yields (7.45 gd.m./dm3) than phosphorus limitation in a nitrogen-rich medium (4.56 gd.m./dm3), with comparable lipid yields (30% and 32%). Regardless of the medium composition, the yeast preferentially accumulated oleic and linoleic acids as well as linolenic acid up to 8.89%. Further, it is crucial to determine the correlation between N/P molar ratios, biomass growth and efficient lipid accumulation. In particular, considering the contribution of phosphorus as a component of coenzymes in many metabolic pathways, including lipid biosynthesis and respiration processes, its importance as a factor in the cultivation of the oleaginous microorganisms was highlighted.

scholarly journals Ligninolytic enzyme production in Pleurotus eryngii depending on the medium composition and cultivation conditions

2005 ◽  
pp. 269-276
Author(s):  
Mirjana Stajic ◽  
Sonja Duletic-Lausevic ◽  
Jelena Vukojevic
Keyword(s):  
Nitrogen Concentration ◽  
Nitrogen Sources ◽  
Ligninolytic Enzyme ◽  
Medium Composition ◽  
Pleurotus Eryngii ◽  
Phenol Red ◽  
Cultivation Conditions ◽  
Carbon And Nitrogen Sources ◽  
Carbon And Nitrogen ◽  
Two Peaks

Pleurotus eryngii produced laccase (Lac) both under conditions of submerged fermentation (SF) and solid-state fermentation (SSF) using all of the investigated carbon and nitrogen sources, while significant peroxidases production occurred only under SSF conditions. The highest levels of Lac activity were found under SF conditions of dry ground mandarine peels (999.5 U/l). After purification of extracellular crude enzyme mixture of P. eryngii which was grown under SF conditions with dry ground mandarine peels it was revealed two peaks of Lac activity and one peak of activity against phenol red in absence of external Mn2+ which was very low (1.4 U/l). Results obtained by purification also showed that the levels of phenol red oxidation in absence of external Mn2+ were higher than phenol red oxidation levels in presence of external Mn2+. In the medium with the best carbon source for Lac production (dry ground mandarine peels), (NH4)2SO4, with a nitrogen concentration of 20 mM, was the most optimum nitrogen source among 8 investigated sources.

scholarly journals Effect of Nutritional Factors and Copper on the Regulation of Laccase Enzymes Production in Pleurotus ostreatus

2021 ◽  
Author(s):  
Dinary Durán-Sequeda ◽  
Daniela Suspes ◽  
Estibenson Maestre ◽  
Manuel Alfaro ◽  
Gumer Pérez ◽  
...  
Keyword(s):  
Nitrogen Source ◽  
Pleurotus Ostreatus ◽  
Culture Media ◽  
Nitrogen Sources ◽  
Fold Increase ◽  
Medium Composition ◽  
Copper Transporter ◽  
Nutritional Factors ◽  
Laccase Genes ◽  
Response Variables

This research aimed to establish the relationship between carbon-nitrogen nutritional factors and copper sulfate on laccase activity (LA) by Pleurotus ostreatus. Culture media composition was tested to choose the nitrogen source. Yeast extract (YE) was selected as a better nitrogen source than ammonium sulfate. Then, the effect of glucose and YE concentrations on biomass production and LA as response variables was evaluated using central composite experimental designs with and without copper. The results showed that the best culture medium composition was glucose 45 gL-1 and YE 15 gL-1, simultaneously optimizing these two response variables. The fungal transcriptome was obtained in this medium with or without copper, and the differentially expressed genes were found. Main up-regulated transcripts included three laccase genes (lacc2, lacc6, and lacc10) regulated by copper, whereas the principal down-regulated transcripts included a copper transporter (ctr1) and a regulator of nitrogen metabolism (nmr1). These results suggest that Ctr1, which facilitates the entry of copper in the cell, is regulated by nutrient-sufficiency conditions. Once inside, copper induces transcription of laccase genes. This finding could explain why a 10 to 20-fold increase in LA occurs with copper compared to cultures without copper when using the optimal concentration of YE as nitrogen sources.

Effects of different nitrogen sources and light paths of flat plate photobioreactors on the growth and lipid accumulation of Chlorella sp. GN1 outdoors

2020 ◽  
Vol 301 ◽  
pp. 122762 ◽  
Author(s):  
Pingzhong Feng ◽  
Zhongbin Xu ◽  
Lei Qin ◽  
Md Asraful Alam ◽  
Zhongming Wang ◽  
...  
Keyword(s):  
Flat Plate ◽  
Lipid Accumulation ◽  
Nitrogen Sources ◽  
Chlorella Sp

Simultaneous enhancement of microalgae biomass growth and lipid accumulation under continuous aeration with 15% CO2

RSC Advances ◽  
2015 ◽  
Vol 5 (63) ◽  
pp. 50851-50858 ◽  
Author(s):  
Yun Huang ◽  
Jun Cheng ◽  
Hongxiang Lu ◽  
Rui Huang ◽  
Junhu Zhou ◽  
...  
Keyword(s):  
Lipid Accumulation ◽  
Nitrogen Deprivation ◽  
Biomass Growth ◽  
Microalgae Biomass

Continuous aeration with 15% CO2 induced nitrogen deprivation during Chlorella PY-ZU1 cultivation, thus simultaneously promoting biomass (2.78 g L−1) and lipid (47.04%) production.

NITROGEN AND PHOSPHORUS LIMITATION OF BIOMASS GROWTH IN A TROPICAL SECONDARY FOREST

2004 ◽  
Vol 14 (sp4) ◽  
pp. 150-163 ◽  
Author(s):  
Eric A. Davidson ◽  
Cláudio J. Reis de Carvalho ◽  
Ima C. G. Vieira ◽  
Ricardo de O. Figueiredo ◽  
Paulo Moutinho ◽  
...  
Keyword(s):  
Secondary Forest ◽  
Phosphorus Limitation ◽  
Biomass Growth ◽  
Nitrogen And Phosphorus ◽  
Tropical Secondary Forest

scholarly journals Lovastatin Production from Cunninghamella blakesleeana under Solid State Fermentation

2021 ◽  
Author(s):  
Janani Balraj ◽  
Thandeeswaran Murugesan ◽  
Vidhya Kalieswaran ◽  
Karunyadevi Jairaman ◽  
Devippriya Esakkimuthu ◽  
...  
Keyword(s):  
Solid State ◽  
Incubation Period ◽  
Solid State Fermentation ◽  
Carbon Sources ◽  
Experimental Studies ◽  
Nitrogen Sources ◽  
Medium Composition ◽  
Critical Parameters ◽  
Physical Parameters ◽  
Cunninghamella Blakesleeana

Abstract Our earlier paper had established the fact that new soil fungi known as Cunninghamella blakesleeana is potent enough to produce lovastatin significantly. At present, there are no reports on the media optimization for the lovastatin production. Hence, the objective is to optimize the fermentation conditions for lovastatin production by Cunninghamella blakesleeana under Solid State fermentation (SSF) condition through screening the critical factors by one factor at a time and then, optimize the factors selected from screening using statistical approaches. SSF was carried using the pure culture of Cunninghamella blakesleeana KP780148.1 with wheat bran as substrate. Initial screening was performed for physical parameters, carbon sources and nitrogen sources and then optimized the selected parameters through PBD and BBD. Screening result indicated the optimum values of the analysed parameter for the maximal production of lovastatin by Cunninghamella blakesleeana were selected. Out of the nine factors MgSO4, (NH4)2SO4, pH and Incubation period were found to influence the lovastatin production significantly after PBD. The optimal levels of these variables and the effect of their mutual interactions on lovastatin production were determined using BBD surface design. The optimum medium composition was found to be MgSO4(0.2 g/L), (NH4)2 SO4 (12.5 g/L), pH (6) and Incubation period (7 days). Experimental studies showed a yield of 7.39 mg/g at the above optimized conditions which were observed to be very nearby to the predicted value and hence the model was successfully validated. Hence, this is the first report on the optimization of critical parameters for lovastatin production by Cunninghamella blakesleeana.

scholarly journals Marine microalgae co-cultured with floc-forming bacterium: Insight into growth and lipid productivity

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11217
Author(s):  
Chin Sze Yee ◽  
Victor Tosin Okomoda ◽  
Fakriah Hashim ◽  
Khor Waiho ◽  
Siti Rozaimah Sheikh Abdullah ◽  
...  
Keyword(s):  
Cell Density ◽  
Chlorella Vulgaris ◽  
Lipid Content ◽  
Lipid Accumulation ◽  
Axenic Culture ◽  
Cell Number ◽  
The Other ◽  
Biomass Growth ◽  
Microalgae Biomass ◽  
Insight Into

This study investigated the effect of co-culturing microalgae with a floc-forming bacterium. Of the six microalgae isolated from a biofloc sample, only Thalassiosira weissflogii, Chlamydomonas sp. and Chlorella vulgaris were propagated successfully in Conway medium. Hence, these species were selected for the experiment comparing microalgae axenic culture and co-culture with the floc-forming bacterium, Bacillus infantis. Results obtained showed that the co-culture had higher microalgae biomass compared to the axenic culture. A similar trend was also observed concerning the lipid content of the microalgae-bacterium co-cultures. The cell number of B. infantis co-cultured with T. weissflogii increased during the exponential stage until the sixth day, but the other microalgae species experienced a significant early reduction in cell density of the bacteria at the exponential stage. This study represents the first attempt at co-culturing microalgae with B. infantis, a floc-forming bacterium, and observed increased biomass growth and lipid accumulation compared to the axenic culture.

Sign in / Sign up

Export Citation Format

Share Document