Production of PHB by a Bacillus megaterium strain using sugarcane molasses and corn steep liquor as sole carbon and nitrogen sources

We investigated the influence of corn steep liquor (CSL) and cassava waste water (CWW) as carbon and nitrogen sources on the morphology and production of biomass and chitosan by Mucor subtilissimus UCP 1262 and Lichtheimia hyalospora UCP 1266. The highest biomass yields of 4.832 g/L (M. subtilissimus UCP 1262) and 6.345 g/L (L. hyalospora UCP 1266) were produced in assay 2 (6% CSL and 4% CWW), factorial design 22, and also favored higher chitosan production (32.471 mg/g) for M. subtilissimus. The highest chitosan production (44.91 mg/g) by L. hyalospora (UCP 1266) was obtained at the central point (4% of CWW and 6% of CSL). The statistical analysis, the higher concentration of CSL, and lower concentration of CWW significantly contributed to the growth of the strains. The FTIR bands confirmed the deacetylation degree of 80.29% and 83.61% of the chitosan produced by M. subtilissimus (UCP 1262) and L. hyalospora (UCP 1266), respectively. M. subtilissimus (UCP 1262) showed dimorphism in assay 4–6% CSL and 8% CWW and central point. L. hyalospora (UCP 1266) was optimized using a central composite rotational design, and the highest yield of chitosan (63.18 mg/g) was obtained in medium containing 8.82% CSL and 7% CWW. The experimental data suggest that the use of CSL and CWW is a promising association to chitosan production.

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Optimization and kinetics studies on exopolysaccharide production using Klebsiella oxytoca ICCF 419 strain, and glucose as substrate

ROMANIAN BIOTECHNOLOGICAL LETTERS ◽

10.25083/rbl/26.1/2214.2222 ◽

2021 ◽

Vol 26 (1) ◽

pp. 2214-2222

Author(s):

CATERINA TOMULESCU ◽

MIȘU MOSCOVICI ◽

ROXANA MĂDĂLINA STOICA ◽

GABRIEL BUJOR ALBU ◽

CLAUDIA SEVCENCO ◽

...

Keyword(s):

Corn Steep Liquor ◽

Klebsiella Oxytoca ◽

Nitrogen Sources ◽

Carbon And Nitrogen Sources ◽

Carbon And Nitrogen ◽

Logistic Equations ◽

Maximum Cell ◽

Steep Liquor ◽

Central Composite ◽

Optimal Formula

The present work aimed to investigate the efficiency of kinetic modeling and Response Surface Methodology (RSM), by employing a Central Composite Rotatable Design (CCRD) and to evaluate the effects of carbon and nitrogen sources, inoculation volume, and bioprocess time on an exopolysaccharide (EPS) producer, Klebsiella oxytoca ICCF 419, in batch fermentation with shaken flasks. Among the kinetic models tested, logistic equations were found to fit accordingly, with a correlation coefficient (R2 ) of 0.999. The interaction between glucose and corn steep liquor was found to have a significant impact on the EPS production, and glucose (2% w/v), and a 5% v/v inoculum of 24 hours age, are sufficiently to positively affect the bioprocess, if it is desired only a maximum cell growth, but not associated with the polymer synthesis. The optimal formula predicted by the RSM design was experimentally validated by the following results: 12.16 g EPS/L and 1.65 dry biomass/L, after 48 hours fermentation.

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Hydrolysis of Corncob Residue by Enzymes from Fungi C1067 and the Products Analysis by Capillary Electrophoresis

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.145.68 ◽

2011 ◽

Vol 145 ◽

pp. 68-72

Author(s):

Jian Lu Ma ◽

Xiao Min Fang ◽

Xin Jiong Guo ◽

Huan Fei Liu ◽

Gui Fu Dai ◽

...

Keyword(s):

Capillary Electrophoresis ◽

Corn Steep Liquor ◽

Nitrogen Sources ◽

Fermentation Medium ◽

Citrate Buffer ◽

Carbon And Nitrogen ◽

Products Analysis ◽

Steep Liquor ◽

Hydrolysis Of ◽

Assay Conditions

To achieve high enzymatic hydrolytic efficiency of corncob residue, one strain, Trichoderma C1067, with the enzyme activity of corncob residue as high as 4.5g/L glucose liberated per hour in 0.5mL crude cellulase and 0.5mL citric acid /sodium citrate buffer under the assay conditions, was carefully studied. The optimal carbon and nitrogen sources used in the fermentation medium are as follows: corncob residues 2.0%, wheat bran 1.5%, corncob 0.5%, rice straw 0.5%, peptone 0.1% and corn steep liquor 4%. The optimal conditions of saccharification for corncob are 55°C and pH 4.0. The sugars gained in the hydrolysate consist of glucose 4.1% and xylose 0.4% after enzymolysis for 72h, tested by capillary electrophoresis.

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