Enhancement of 2,3-Butanediol Production byKlebsiella oxytocaPTCC 1402

Optimal operating parameters of 2,3-Butanediol production usingKlebsiella oxytocaunder submerged culture conditions are determined by using Taguchi method. The effect of different factors including medium composition, pH, temperature, mixing intensity, and inoculum size on 2,3-butanediol production was analyzed using the Taguchi method in three levels. Based on these analyses the optimum concentrations of glucose, acetic acid, and succinic acid were found to be 6, 0.5, and 1.0 (% w/v), respectively. Furthermore, optimum values for temperature, inoculum size, pH, and the shaking speed were determined as 37°C, 8 (g/L), 6.1, and 150 rpm, respectively. The optimal combinations of factors obtained from the proposed DOE methodology was further validated by conducting fermentation experiments and the obtained results revealed an enhanced 2,3-Butanediol yield of 44%.

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Isolation, Identification and Characterization of Bioflocculant-Producing Bacteria from Activated Sludge of Vulindlela Wastewater Treatment Plant

Applied Microbiology ◽

10.3390/applmicrobiol1030038 ◽

2021 ◽

Vol 1 (3) ◽

pp. 586-606

Author(s):

Nkanyiso Celukuthula Nkosi ◽

Albertus K. Basson ◽

Zuzingcebo G. Ntombela ◽

Tsolanku S. Maliehe ◽

Rajasekhar V. S. R. Pullabhotla

Keyword(s):

Activated Sludge ◽

Treatment Plant ◽

16S Rrna Gene Sequencing ◽

Industrial Applications ◽

Culture Conditions ◽

Inoculum Size ◽

Medium Composition ◽

Rrna Gene ◽

Sequencing Analysis ◽

Optimal Medium

The low microbial flocculant yields and efficiencies limit their industrial applications. There is a need to identify bacteria with high bioflocculant production. The aim of this study was to isolate and identify a bioflocculant-producing bacterium from activated sludge wastewater and characterise its bioflocculant activity. The identification of the isolated bacterium was performed by 16S rRNA gene sequencing analysis. The optimal medium composition (carbon and nitrogen sources, cations and inoculum size) and culture conditions (temperature, pH, shaking speed and time) were evaluated by the one-factor-at-a-time method. The morphology, functional groups, crystallinity and pyrolysis profile of the bioflocculant were analysed using scanning electron microscope (SEM), Fourier transform infrared (FTIR) and thermogravimetric (TGA) analysis. The bacterium was identified as Proteus mirabilis AB 932526.1. Its optimal medium and culture conditions were: sucrose (20 g/L), yeast extract (1.2 g/L), MnCl2 (1 g/L), pH 6, 30 °C, inoculation volume (3%), shaking speed (120 rpm) for 72 h of cultivation. SEM micrograph revealed the bioflocculant to be amorphous. FTIR analysis indicated the presence of hydroxyl, carboxyl and amino groups. The bioflocculant was completely pyrolyzed at temperatures above 800 °C. The bacterium has potential to produce bioflocculant of industrial importance.

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Isolation and Optimization of Culture Conditions of a Bioflocculant-Producing Fungi from Kombucha Tea SCOBY

Microbiology Research ◽

10.3390/microbiolres12040070 ◽

2021 ◽

Vol 12 (4) ◽

pp. 950-966

Author(s):

Phakamani H. Tsilo ◽

Albertus K. Basson ◽

Zuzingcebo G. Ntombela ◽

Tsolanku S. Maliehe ◽

Rajasekhar V. S. R. Pullabhotla

Keyword(s):

Nitrogen Sources ◽

Xrd Analysis ◽

Culture Conditions ◽

Inoculum Size ◽

Medium Composition ◽

Rrna Gene ◽

Environmental Friendliness ◽

Pichia Kudriavzevii ◽

Kombucha Tea ◽

Ft Ir

Biolocculants are gaining attention in research due to their environmental friendliness and innocuousness to human in comparison to the conventional flocculants. The present study aimed to investigate the ability of fungi from Kombucha tea SCOBY to produce effective bioflocculant in bulk. A 16S rRNA gene sequence analysis was utilized to identify the isolate. The medium composition (carbon and nitrogen sources) and culture conditions (inoculum size, temperature, shaking speed, pH, and time) were optimized using one-factor-at-a-time method. The functional groups, morphology, and crystallinity of the bioflocculant were evaluated using Fourier transform infrared (FT-IR), scan electron microscope (SEM) and X-ray diffractometry (XRD). The fungus was found to be Pichia kudriavzevii MH545928.1. It produced a bioflocculant with flocculating activity of 99.1% under optimum conditions; 1% (v/v) inoculum size, glucose and peptone as nutrient sources, 35 °C, pH 7 and the shaking speed of 140 rpm for 60 h. A cumulus-like structure was revealed by SEM; FT-IR displayed the presence of hydroxyl, carboxyl, amine, and thiocynates. The XRD analysis demonstrated the bioflocculant to have big particles with diffraction peaks at 10° and 40° indicating its crystallinity. Based on the obtained results, P. kudriavzevii MH545928.1 has potential industrial applicability as a bioflocculant producer.

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Effects of Medium Components and Culture Conditions on Mycelial Biomass and the Production of Bioactive Ingredients in Submerged Culture of Xylaria nigripes (Ascomycetes), a Chinese Medicinal Fungus

International Journal of Medicinal Mushrooms ◽

10.1615/intjmedmushrooms.v16.i5.30 ◽

2014 ◽

Vol 16 (5) ◽

pp. 431-447 ◽

Cited By ~ 2

Author(s):

Jian-Zhi Chen ◽

Hui-Chen Lo ◽

Fang-Yi Lin ◽

Shih-Liang Chang ◽

Changwei Hsieh ◽

...

Keyword(s):

Submerged Culture ◽

Culture Conditions ◽

Mycelial Biomass ◽

Medium Components ◽

Medicinal Fungus ◽

Bioactive Ingredients

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Enhanced Bioactive Exopolysaccharide Production by Mossy Maze Polypore, Cerrena unicolor (Higher Basidiomycetes) in Submerged Culture Conditions

International Journal of Medicinal Mushrooms ◽

10.1615/intjmedmushrooms.v17.i7.40 ◽

2015 ◽

Vol 17 (7) ◽

pp. 639-648

Author(s):

Burcu Altinay ◽

Ayse Betul Karaduman ◽

Bukay Yenice Gursu ◽

Mustafa Yamac

Keyword(s):

Submerged Culture ◽

Culture Conditions ◽

Exopolysaccharide Production ◽

Cerrena Unicolor

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Investigation of culture conditions by Response Surface Methodology and kinetic modeling for exopolysaccharide production by Klebsiella oxytoca ICCF 419 strain, using lactose as substrate

ROMANIAN BIOTECHNOLOGICAL LETTERS ◽

10.25083/rbl/25.6/2033.2044 ◽

2020 ◽

Vol 25 (6) ◽

pp. 2033-2044

Author(s):

CATERINA TOMULESCU ◽

◽

MIŞU MOSCOVICI ◽

ROXANA MĂDĂLINA STOICA ◽

GABRIEL BUJOR ALBU ◽

...

Keyword(s):

Citric Acid ◽

Klebsiella Oxytoca ◽

Fermentation Medium ◽

Culture Conditions ◽

Biomass Growth ◽

Initial Value ◽

Substrate Consumption ◽

Polysaccharide Production ◽

Crude Polysaccharide ◽

Central Composite

The objective of this work was to optimize the bioprocess parameters, using Klebsiella oxytoca ICCF 419 to obtain an exopolysaccharide based on lactose as substrate. A kinetic study was employed and Logistic and Gompertz models were applied to describe the polysaccharide production, in relation with biomass growth and substrate consumption. The RSM methodology based on Central Composite Rotatable Design was used to evaluate and optimize the effect of lactose, corn extract, KH2PO4 and citric acid concentrations as independent variables on the polysaccharide production, biomass growth and substrate consumption as the response functions. The interaction effects and optimal parameters were obtained using Design Expert Software (version 9.0.6.2). The significance of the variables and their interactions was tested by means of ANOVA analysis with a 99% confidence level. The optimum culture conditions were determined and the model prediction was compared with experimental results. At an initial value of 23.45 for the C/N in the fermentation medium, the strain produces 17.41 g/L of crude polysaccharide and 2.53 g/L dry biomass. The EPS production was significantly influenced by lactose, corn extract and KH2PO4, while the citric acid had no influence. The biomass growth was influenced by the corn extract, KH2PO4 and citric acid.

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Barley somatic embryogenesis-an attempt to modify variation induced in tissue culture

Journal of Biological Research-Thessaloniki ◽

10.1186/s40709-021-00138-5 ◽

2021 ◽

Vol 28 (1) ◽

Author(s):

Renata Orłowska

Keyword(s):

Tissue Culture ◽

Somatic Embryogenesis ◽

Taguchi Method ◽

Culture Conditions ◽

Dna Demethylation ◽

Silver Ion ◽

Donor Plant ◽

In Vitro Tissue Culture ◽

Induced Variation

Abstract Background Somatic embryogenesis is a phenomenon carried out in an environment that generates abiotic stress. Thus, regenerants may differ from the source of explants at the morphological, genetic, and epigenetic levels. The DNA changes may be the outcome of induction media ingredients (i.e., copper and silver ions) and their concentrations and time of in vitro cultures. Results This study optimised the level of copper and silver ion concentration in culture media parallel with the induction medium longevity step towards obtaining barley regenerants via somatic embryogenesis with a minimum or maximum level of tissue culture-induced differences between the donor plant and its regenerants. The optimisation process is based on tissue culture-induced variation evaluated via the metAFLP approach for regenerants derived under varying in vitro tissue culture conditions and exploited by the Taguchi method. In the optimisation and verification experiments, various copper and silver ion concentrations and the different number of days differentiated the tested trials concerning the tissue culture-induced variation level, DNA demethylation, and de novo methylation, including symmetric (CG, CHG) and asymmetric (CHH) DNA sequence contexts. Verification of optimised conditions towards obtaining regenerants with minimum and maximum variability compared to donor plants proved useful. The main changes that discriminate optimised conditions belonged to DNA demethylation events with particular stress on CHG context. Conclusions The combination of tissue culture-induced variation evaluated for eight experimental trials and implementation of the Taguchi method allowed the optimisation of the in vitro tissue culture conditions towards the minimum and maximum differences between a source of tissue explants (donor plant) and its regenerants from somatic embryos. The tissue culture-induced variation characteristic is mostly affected by demethylation with preferences towards CHG sequence context.

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Microwave Irradiated Acetylation of p-Anisidine: A Step towards Green Chemistry

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.1770 ◽

2008 ◽

Vol 6 (1) ◽

Cited By ~ 2

Author(s):

Mousumi Chakraborty ◽

Vaishali Umrigar ◽

Parimal A. Parikh

Keyword(s):

Acetic Acid ◽

Reaction Time ◽

Green Chemistry ◽

Acetic Anhydride ◽

Microwave Irradiation ◽

Organic Solvent ◽

Reaction Times ◽

Microwave Energy ◽

Operating Parameters ◽

Feed Composition

The present study aims at assessing the effect of microwave irradiation against thermal heat on the production of N-acetyl-p-anisidine by acetylation of p-anisidine. The acetylation of p-anisidine under microwave irradiation produces N-acetyl-p-anisidine in shorter reaction times, which offers a benefit to the laboratories as well as industries. It also eliminates the use of excess solvent. Effects of operating parameters such as reaction time, feed composition, and microwave energy and reaction temperature on selectivity to the desired product have been investigated. The results indicate as high as a 98% conversion of N-acetyl-p-anisidine can be achieved within 12-15 minutes using acetic acid. The use of acetic acid as an acetylating agent against conventionally used acetic anhydride eliminates the handling of explosive acetic anhydride and also the energy intensive distillation step for separation of acetic acid. Organic solvent like acetic anhydride are not only hazardous to the environment, they are also expensive and flammable.

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